Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: Widewing on February 24, 2007, 12:45:19 PM
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I've dabbled with many WWII sims and games, and I am fully convinced that the flight modeling in Aces High is the closest to reality of any of the others.
Nonetheless, there are some issues that may deserve review as time and priorities permit.
1. Our current F6F-5 is too slow (at least 20 mph) above 18,000 feet when compared to flight test data of the era. It also has flaps with multiple position settings. In reality, the F6Fs had no intermediate flaps positions. They were either up or full down. In addition, the F6F-5 suffers from an odd dynamic instability in its roll axis when slow with flaps deployed. This is exactly opposite of the F6F's excellent roll stability when near stall and dirtied up for landing.
2. The AH2 P-40E is equipped with WEP. Real P-40Es were not so equipped. Our P-40E is far more like the later P-40K, fitted with the V-1710-73/FR4 engine.
3. In-game testing of the AH2 P-40B reveals that it performs like the much heavier P-40C. The C model was fitted with shackles and plumbing for and external drop tank. In addition, the C model carried more armor. A real P-40B was just as fast as the P-40E, but was lighter and more agile. Due to having internally sealed fuel tanks, the P-40C had less internal fuel capacity than the P-40B.
4. When the last change was made to the drag model, some aircraft suffered a loss of handling and maneuvering performance. Chief among that group was the P-51s. For example, at 25% fuel, without flaps, a P-51B has a lower wing loading than the P-47D-11. It also has a very similar coefficient of lift. It should out-turn the Jug. Yet, it does not. Once flaps are deployed it gets worse for the Mustang. I have detailed the issue in this thread. (http://forums.hitechcreations.com/forums/showthread.php?s=&threadid=185075&perpage=40&pagenumber=3)
5. Flap effect on turn performance and drag is somewhat odd and inconsistant throughout the plane set. I will be testing this thoroughly in the near future, comparing results from older versions of the software to the current version.
6. Some aircraft demonstrate unusual stall behavior when flown into a power-off nose-high stall.
7. While Aces High limits WEP to five or ten minutes depending upon type. there is no accounting for comsuming the various types of water/ADI. WEP use is based upon engine temperature, which allows for recovery of full WEP duration. There is no option to exceed recommended WEP duration, even though there is plenty of test data where WEP was used for as much as 15 minutes during max power climb testing. Perhaps a variable could be introduced that would induce an engine failure randomly if WEP were used beyond the recommended maximum.
8. P-factor does not appear to be modeled.
9. Of all American Naval aircraft, only the F4Us should have tail hook use tied to landing gear position. Grumman aircraft and the SBD should be able to lower their tail hooks independently of landing gear position.
10. Machine gun ammunition load-outs could be varied in the F6F and F4U.
11. The A6M2 dives far too fast, greatly exceeding the speed at which it should suffer damage. Its dive behavior is vastly different (read that as superior) than that of the strengthened A6M5.
12. Both Yaks can dive at extremely high speeds, but can do so with very good control and with virtually no compressibility effects.
Please feel free to add to this list, but please make sure you can back up your points with primary source data or other credible sources (for example, the History Channel isn't a good source).
My regards,
Widewing
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Originally posted by Widewing
The AH2 P-40E is equipped with WEP. Real P-40Es were not so equipped. Our P-40E is far more like the later P-40K, fitted with the V-1710-73/FR4 engine.
But is the actual power rating higher than it should be? American fighters did not have a special War Emergency Power control. It was activated simply by firewalling the throttle (usually breaking through a wire so that the ground crew could immediately tell whether or not you used War Emergency Power). So really all American airplanes should not have a War Emergency Power toggle, but instead should simply be able to get the same amount of power by simply pushing the throttle wide open.
I'd like to add that the P-38, while being very close to reality in stalling characteristics, still has some tendency to drop off on a wing even when there is no slip or skid.
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My source of information involves animal entrails and three naked virgins...
Is that OK...?
J/K :p
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I don't have the data myself, but F4UDOA has posted it in the past: The F4U-1D could also carry ordinance on the center pylon. There are loads of 3xbombs, or 2xbombs + 1xDT on DOA's charts.
The F4U-1 (birdcage) should not have WEP (also per previous threads). In honesty, IIRC the birdcage also didn't carry ordinance standard, but that this was rather a field modification.
An option to fly as a land-based F4U-1A without the arrestor gear (and associated weight) and the weight of wing fold mechanisms would be nice. Many 1As were built that way out of the factory, (especially the Goodyear builds) and quite a few more were field-modified to remove them.
Also, while not a FLIGHT issue, I've shown in this thread (http://forums.hitechcreations.com/forums/showthread.php?s=&threadid=198875) that the gunsight for the bubble-top Hogs should be doubled in size, and that of the FM-2 and F6F need to be very slightly enlarged (see my posts using the Fw-190D to scale the sight). I haven't tested the historical sights of other aircraft, but it's reasonable to assume that some others might be incorrectly sized if one wanted to use the historical sights as well.
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Originally posted by Benny Moore
But is the actual power rating higher than it should be? American fighters did not have a special War Emergency Power control. It was activated simply by firewalling the throttle (usually breaking through a wire so that the ground crew could immediately tell whether or not you used War Emergency Power). So really all American airplanes should not have a War Emergency Power toggle, but instead should simply be able to get the same amount of power by simply pushing the throttle wide open.
I'd like to add that the P-38, while being very close to reality in stalling characteristics, still has some tendency to drop off on a wing even when there is no slip or skid.
Benny not all have a throttle. So to simulate pushing past the wire is the p key.
Bronk
Edit : Some throttles do not have a detent to simulate the wire either.
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Originally posted by Saxman
I don't have the data myself, but F4UDOA has posted it in the past: The F4U-1D could also carry ordinance on the center pylon. There are loads of 3xbombs, or 2xbombs + 1xDT on DOA's charts.
The F4U-1 (birdcage) should not have WEP (also per previous threads). In honesty, IIRC the birdcage also didn't carry ordinance standard, but that this was rather a field modification.
This reminds me.... The F6F-5 should be able to carry bombs on both pylons AND a belly tank. In AH2 it's either bombs OR a belly tank.
My regards,
Widewing
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Originally posted by Bronk
Benny not all have a throttle. So to simulate pushing past the wire is the p key.
Bronk
Edit : Some throttles do not have a detent to simulate the wire either.
I am aware of this. My own throttle is merely a slider. However, the wire was not really a physical obstruction; real pilots usually use the manifold pressure guage to determine power, not the actual throttle.
But my main point is that what the War Emergency Power key does in game was done in real life by simply giving full throttle. Thus, saying "the P-40 should not be able to use the War Emergency Power key" doesn't really make sense, as that just simulates firewalling the throttle.
So my question for Widewing is, is the highest power rating available to the P-40E in Aces High II correct, or not? If it is, then it doesn't make sense to take away the ability to use the War Emergency Power key unless you raise the military power rating to the same rating. But if it isn't, then I agree that there's a problem.
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Originally posted by Benny Moore
So my question for Widewing is, is the highest power rating available to the P-40E in Aces High II correct, or not? If it is, then it doesn't make sense to take away the ability to use the War Emergency Power key unless you raise the military power rating to the same rating. But if it isn't, then I agree that there's a problem.
In the game, MIL power MAP rating is about 46 in/hg. Increasing to WEP boosts MAP to about 53 in/hg. All data that I have for the V-1710-39 in the P-40E indicates 46.2 in/hg MIL power (no WEP rating).
My regards,
Widewing
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Originally posted by Widewing
4. When the last change was made to the drag model, some aircraft suffered a loss of handling and maneuvering performance. Chief among that group was the P-51s. For example, at 25% fuel, without flaps, a P-51B has a lower wing loading than the P-47D-11. It also has a very similar coefficient of lift. It should out-turn the Jug. Yet, it does not. Once flaps are deployed it gets worse for the Mustang. I have detailed the issue in this thread. (http://forums.hitechcreations.com/forums/showthread.php?s=&threadid=185075&perpage=40&pagenumber=3)
6. Some aircraft demonstrate unusual stall behavior when flown into a power-off nose-high stall.
8. P-factor does not appear to be modeled.
Widewing- a few comments regarding #4,#6, & #8:
#4 - I didn't post this in the other thread but something to consider is the difference that power-loading has on turn performance between the P-47D-11 and P-51B. The D-11 given the weights you listed has a better power-loading compared to that the P-51B. It's conceivable that in a sustained turn the P-47D-11 has an advantage in turn radius and rate vs. the P-51B even though this isn't true from an instantaneous turn perspective.
#6 - we discussed this in the spit death stall thread but I actually brokedown your spit stall film into frames for analysis. I'll post this sometime. It's pretty interesting to consider the physics at work to figure out what makes sense vs. not in cases where the aircraft is in very high angles of attack at very low airspeeds.
#8 - P-factor is modeled. If you look at this pic from Pyro from the stall speed thread you'll see it.
(http://hitechcreations.com/pyro/poweron01.jpg)
Notice the assymetric thrust of the prop: right, top, & left and notice how they are different and how the downward side (right) of the prop has a higher thrust than the upward side (left) of the prop.
Always appreciative of your well-reasoned posts.
Tango, XO
412th FS Braunco Mustangs
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Originally posted by dtango
Widewing- a few comments regarding #4,#6, & #8:
#4 - I didn't post this in the other thread but something to consider is the difference that power-loading has on turn performance between the P-47D-11 and P-51B. The D-11 given the weights you listed has a better power-loading compared to that the P-51B. It's conceivable that in a sustained turn the P-47D-11 has an advantage in turn radius and rate vs. the P-51B even though this isn't true from an instantaneous turn perspective.
#6 - we discussed this in the spit death stall thread but I actually brokedown your spit stall film into frames for analysis. I'll post this sometime. It's pretty interesting to consider the physics at work to figure out what makes sense vs. not in cases where the aircraft is in very high angles of attack at very low airspeeds.
#8 - P-factor is modeled. If you look at this pic from Pyro from the stall speed thread you'll see it.
(http://hitechcreations.com/pyro/poweron01.jpg)
Notice the assymetric thrust of the prop: right, top, & left and notice how they are different and how the downward side (right) of the prop has a higher thrust than the upward side (left) of the prop.
Always appreciative of your well-reasoned posts.
Tango, XO
412th FS Braunco Mustangs
My issues related to the P-51B vs P-47 are also supported by Brit data that shows the Mustang III (P-51B) turns much smaller circles than the P-47. There is also testing at Eglin Field that supports the argument.
From http://www.wwiiaircraftperformance.org:
PROOF DEPARTMENT
TACTICAL COMBAT SECTION
ARMY AIR FORCES PROVING GROUND COMMAND, EGLIN FIELD, FLORIDA
FINAL REPORT ON TACTICAL SUITABILITY OF THE P-47C-1 TYPE AIRCRAFT
18 December 1942
1. OBJECT:
To determine the relative tactical value of the P-47C-1 type aircraft for combat service.
(snip)
3) Maneuverability -- The P-47C-1 was flown in mock combat against the P-38F, P-39D1, P-40F, and the P-51.
(a) It had superior rate of aileron roll at all speeds, and especially at high speed to all American fighter contemporary types, none could follow it in a fast reverse turn.
(b) The turning circle of this aircraft was larger than any of the other types engaged in combat. The high wing loading makes the plane mush in all maneuvers controlled by the elevators, and this also causes high speed stall in tight turns.
(c) It was slightly slower in acceleration from level flight at fifteen-thousand (15,000) than all types except the P-40F, which was decidedly slower, however, the distance gained in the initial acceleration was never greater than fifty (50) yards and the P-47C-1 rapidly overhauled and passed the other types. This test was with closed shutters and the liquid cooled engines rapidly overheated, the shutters had to be opened and the planes decreased a good deal in speed allowing P-47C-1 to run away rapidly. In push-overs with maximum manifold pressure the P-47 accelerated faster and drew away from all other types.
(d) In testing the zoom ability of the P-47C-1 it was found that from level flight and dives, the zoom was comparable with the P-40F. The P-39D1, P-38F, and P-51 have greater zooming ability.
(e) In close fighting the P-47C-1, due to its faster aileron roll, can quickly reverse turn and break off the combat almost at will. However, due to the large turning circle and low rate of climb, it is deemed inadvisable to attempt to dog fight with any type of enemy fighter now used in the combat area.
In short, the P-51B should run circles around the P-47D-11.
(http://www.wwiiaircraftperformance.org/wade-turning.jpg)
As to the stall behavior, I can stall an aircraft and it drops straight down without a hint of rotation. In the case of the Mosquito, it has 8,000 lb of thrust and the corresponding torque. Both are ignored and the aircraft has zero forward motion, while wings are level and without any rotation whatsoever. I have a real problem accepting that this is normal behavior, especially since this behavior was introduced with an update to the software and had not existed prior.
If P-factor is modeled correctly, I would think that there should be some slipstream impingement on the rudder. I don't see any. Which is why it is impossible to perform a true hammerhead stall.
My regards,
Widewing
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Widewing, when doing your testing please can you take a look at the torque effects on (especially late war) aircraft?
Some late war rides seem to suffer very little whilst others seem harshly penalised.
I fly both LA7 and N1K a fair bit and neither of them seem to suffer ANY adverse effects of torque.
Thanks.
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WEP in AH is a very generic term. P40Es didn't have it, nor did birdcage F4us, but they DID have a "max power" that usually was limited to 5-10 minutes before the engine overheated.
When you hit P you're not injecting go-juice, you're just saying "Enable the highest settings that can only be used temporarily.
As for the go-juice not being modeled: I think they did that on purpose. Just my intuition. I think they wanted to simplify engines to a big degree.
EDIT: Oh, the newer models (f4us) might have their FMs re-done every time they're upgraded. The Mossie might get fixed, but only when they redo the entire plane. There's some other planes with unusual flight characteristics, as well. Most of them are generation 1 planes.
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The Mosquito model needs to be checked too. Pull the stick had and it will enter the comical spin:rofl
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And what is up with Ki-84 breaking up at 450mph in dive. I need to see report of 84's breaking up @ 450mph dive in real life (if it even exists...lol)
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Widewing:
I've looked over the Brit report. Thanks for providing the data from the USAAF Eglin report. You probably have the AHT turn performance comparison data from the Joint Fighter Conference as well.
Not sure about the Brit report but the Eglin and the AHT performance numbers appears to be derived from instantaneous turn performance. I absolutely concur that the P-47D-11 has a higher wing loading vs. the P-51B and therefore should be worse in instantaneous turn performance. One way we could check this is checking the 1-g level stall speeds of the both aircraft. Maybe someone has the time to use Brooke's method to test the AH models to verify which one has the higher wing loading by checking 1-g stall speeds.
Sustained turn performance however is something else altogether. Just like wing-loading is a rough measure of instantaneous turn performance, power-loading gives us some insight into possible differences in sustained turn performance. From the figures you quoted in the other P-51 thread the P-47D-11 has a better power-loading compared to that the P-51.
On the Mossie, I didn't realize it didn't have counter-rotating props and haven't thought through the dynamics of that situation. Post stall characteristics especially at extremely high angles of attack can be really tricky to analyze.
Just a note on p-factor - p-factor and corkscrewing propwash (propwash impingement on the rudder) are two different things. P-factor is basically the prop-disc producing assymetric thrust due to the down-going blade having a higher velocity therefore producing more lift/thrust vs. the upgoing blade when the prop is at some angle to the relative to freestream air. Your point is taken however regarding yawing moment due to propwash but I think after we breakdown the AH "deep stall" a bit you'll see what's going on. When I get a chance I'll organize and post the frame by frame analysis.
Tango, XO
412th FS Braunco Mustangs
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Originally posted by Benny Moore
American fighters did not have a special War Emergency Power control.
Late model P-47D's (after the D-21 block) had a manual water injection control. The pilot had to manually engage water injection above 52" of MP in order to achieve the higher WEP manifold pressures or risk detonation. The throttle controlled the MP, but without engaging the water injection control, they could damage the engine at the higher MP. The M and N models that water injection was automatically controlled by the throttle. I don't know how the water injection was controlled on the D-11 through D-20 blocks. I have no idea how the F4U or F6F's were setup.
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Originally posted by Widewing
4. When the last change was made to the drag model, some aircraft suffered a loss of handling and maneuvering performance. Chief among that group was the P-51s. For example, at 25% fuel, without flaps, a P-51B has a lower wing loading than the P-47D-11. It also has a very similar coefficient of lift. It should out-turn the Jug. Yet, it does not. Once flaps are deployed it gets worse for the Mustang. I have detailed the issue in this thread. (http://forums.hitechcreations.com/forums/showthread.php?s=&threadid=185075&perpage=40&pagenumber=3)
6. Some aircraft demonstrate unusual stall behavior when flown into a power-off nose-high stall.
Please feel free to add to this list, but please make sure you can back up your points with primary source data or other credible sources (for example, the History Channel isn't a good source).
#4
From what I see in the game, P51B handily out turns the D11 when the speeds gets slow. I'm pretty sure that they were not historically tested flying circles at 100 mph with flaps full out. If there is something wrong with P51's flaps you will not find it in such comparative reports.
Also, that figure of turning circles you keep posting is out of scale misleading. The spitfire does not turn at a third of a P47/Tempest radius, and P51 does not turn in half a P47 radius. I'm also pretty sure that the tempest could turn tighter than a P47. It most definitly does in the game. That figure is symbolic "this is smaller than that", but not by how much.
#6
The mosquito is perhaps the most obvious problematics FM. The tail wiggleing (yaw instability), the sudden departures, the flat spins and deep stalls unique to it (maybe also the spit I) are clear indications of that. Couple that with the flamable damage model and the chosen version, the slower night version, to kill this most unique and cool WWII plane.
Originally posted by dtango
On the Mossie, I didn't realize it didn't have counter-rotating props and haven't thought through the dynamics of that situation. Post stall characteristics especially at extremely high angles of attack can be really tricky to analyze.
[/B]
It will have about twice the torque give or take secondary effects. But it is also a much heavier plane with large wingspan to control it. Some adverse effects are reduced (prop wash on the tail for instance).
What happens in a deep stall is that the plane turns into a rock. The airflow on the surfaces is in completly wrong direction, plus turbulant, and you can't use any simple "lift" or "drag" or thrust equations. It is the same as trying to calculate the airflow around a giraffe. I have absolutely no idea how AH handles this, but this is one area where hand corrections and guesses are legitimate. If anything, I think most planes are too easily controled near and past stalls.
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(http://hitechcreations.com/pyro/poweron01.jpg)
Not being an expert, and not knowing what P-Factor is (Other Than Pucker Factor)
FARK THAT PIC IS COOL
Next time someone starts mouthing off over the Flight model I am gonna point them at this..
To the guys at HTC
NOTE: Dont bother explaining P-Factor... It will just cause a stack overflow.... :p
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The dogs of war are awakened once again,,,,,,
I have another P-51 chart showing the -39 with WEP (56") up to 9000' but I can't seem to locate it but this is from my P-40E manual;
Ah nuts, I can't post the Specific Engine Flight Chart..............I'm behind this stupid firewall the Saudis have put up which prevents me from establishing a URL.
Someone give me your email bitte
Ok I threw them a bone now they are going to sleep.
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Originally posted by kreighund
The dogs of war are awakened once again,,,,,,
I have another P-51 chart showing the -39 with WEP (56") up to 9000' but I can't seem to locate it but this is from my P-40E manual;
Ah nuts, I can't post the Specific Engine Flight Chart..............I'm behind this stupid firewall the Saudis have put up which prevents me from establishing a URL.
Someone give me your email bitte
Ok I threw them a bone now they are going to sleep.
krieghund - you can send it to tango-p51@hotmail.com and I'll post it for you.
Tango, XO
412th FS Braunco Mustangs
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Originally posted by kreighund
The dogs of war are awakened once again,,,,,,
I have another P-51 chart showing the -39 with WEP (56") up to 9000' but I can't seem to locate it but this is from my P-40E manual;
Ah nuts, I can't post the Specific Engine Flight Chart..............I'm behind this stupid firewall the Saudis have put up which prevents me from establishing a URL.
Up on Zeno's there is a .pdf version of the Flight Operational Instruction Chart for the P-40D/E. It shows 45.5 in/hg for takeoff and 44.6 in/hg for MIL power with the V-1710-39/F3R engine.
My regards,
Widewing
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Originally posted by bozon
#4
From what I see in the game, P51B handily out turns the D11 when the speeds gets slow. I'm pretty sure that they were not historically tested flying circles at 100 mph with flaps full out. If there is something wrong with P51's flaps you will not find it in such comparative reports.
Also, that figure of turning circles you keep posting is out of scale misleading. The spitfire does not turn at a third of a P47/Tempest radius, and P51 does not turn in half a P47 radius. I'm also pretty sure that the tempest could turn tighter than a P47. It most definitly does in the game. That figure is symbolic "this is smaller than that", but not by how much.
Several of us have tested both aircraft for minimum turn radius at full flaps w/WEP. The P-47D-11 turns a circle about 140 feet smaller (70 ft smaller radius) than the P-51B and maintains a faster rate of turn as well.
The P-51D does even worse.
Now, as to that chart that bothers you; it was never intended to show a precise measurement, but to provide a reference only. In every Brit test I've read, the P-51B/Mustang III out-turned every contemporary with the exception of the Mk.IX/XIV/XVI Spitfires. That chart shows this in a simplified manner. Here is the text that accompanies the chart in the document (found here) (http://www.wwiiaircraftperformance.org/sl-wade.html).
"In circumstances where the ability to turn quickly or tightly are infinitely variable, and where two aircraft are nearly the same, such as the Tempest V and Thunderbolt II, a great deal depends on the ability of the pilots. Speed must be taken into account if the results are going to be of any real value.
For example, if a Tempest dives on a Thunderbolt with an overtaking speed of only 50 mph, the Thunderbolt will easily be able to avoid the attack by turning, although at the same speed in the hands of equally competent pilots, the Tempest will outmanoeuvre the Thunderbolt. This advantage, however, is no by any means so apparent at high altitudes, due to the greater engine efficiency of the Thunderbolt above 25,000ft.
Similarly, where low-altitude and high-altitude fighters are compared any advantage shown by the former will be reduced as the high-altitude fighter gets nearer to its best operational altitude. After taking all these considerations into account, the position of the aircraft relative to each other will be seen from the diagram.
Once again, the Spitfire maintains top place, followed by the Mustang, Meteor, Tempest and Thunderbolt. Too much regard to this order should not be paid, particularly by the individual who will angrily recall the occasion when he out-turned a Meteor when flying his Tempest. This sort of thing is inevitable, but we can only repeat that where the circumstances are common to both aircraft, these positions are not far wrong."
Finally, if we go back to older versions of Aces High, including AH1, the P-51B turned a slightly smaller circle than the P-47D-11. I have 3 different versions installed.
My regards,
Widewing
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Originally posted by mussie
FARK THAT PIC IS COOL
Next time someone starts mouthing off over the Flight model I am gonna point them at this..
To the guys at HTC
I agree. In fact, I delight in throwing that very picture at the IL-2 fanboys every time they start gushing about IL-2 being the paragon of flight model realism (it is far from that). It usually shuts them up for a while.
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Heh, I thought the P-51s seemed a bit too much like flying bricks these days...
...However, they're not my biggest complaint. It's the Il-2 Sturmovik's unbelievably flimsy nose armor. Every single time a get a hit anywhere near the nose, the radiator is killed. Having that happen somewhat often would lead me to believe that the Sturmovik just had insufficient nose armor, but since it happes every time, I've formulated the opinion that the armor model has a few bugs that need to be ironed out.
Other Sturmovik pilots will attest to this. Not that it's my main flight of choice (that would probably be the 109 series), but as far as Jabo work is concerned, it's the best there is. Save for that radiator.
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Originally posted by Fruda
Heh, I thought the P-51s seemed a bit too much like flying bricks these days...
...However, they're not my biggest complaint. It's the Il-2 Sturmovik's unbelievably flimsy nose armor. Every single time a get a hit anywhere near the nose, the radiator is killed. Having that happen somewhat often would lead me to believe that the Sturmovik just had insufficient nose armor, but since it happes every time, I've formulated the opinion that the armor model has a few bugs that need to be ironed out.
Other Sturmovik pilots will attest to this. Not that it's my main flight of choice (that would probably be the 109 series), but as far as Jabo work is concerned, it's the best there is. Save for that radiator.
Il2 was fixed. They were taking massive damage from tank rounds and flying away.
You have gotten use to the overmodel. No more hoing infinitly.
Bronk
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Widewing,
I believe you are spot on about the F6F-5's top speed being undermodeled.
One of the F6F-3s that were pulled from the production line and experimented on to increase the Hellcat's top speed, included the following modifications: a redesigned engine cowling yielding a more streamlined nose; a water-injection system for increased horsepower; a high-gloss dark sea blue paint that greatly decreased the drag of the non-specular paint used on the -3.
In January of 1944, one of these modified -3s hit 410mph at 20,000 feet. It's some what unrealistic for some to state that production -5s were some 20 to 30 mphs slower than this.
Regards, Shuckins
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Naval Acceptance trials of F6F-5's (http://www.wwiiaircraftperformance.org/f6f/f6f-5-72731.pdf)
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Originally posted by F4UDOA
Naval Acceptance trials of F6F-5's (http://www.wwiiaircraftperformance.org/f6f/f6f-5-72731.pdf)
This shows that they acknowledged that the test aircraft was way down on power, yet still managed 391 mph at MIL power (not Combat power w/water injection).
My regards,
Widewing
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Much of that performance is based on condition of the Aircraft. The 1944 test that shows 391MPH at Mil power the F6F has one pylon attached. The 1945 test has a max speed of 379MPH at mil power with 6 rocket stubs attached. Both test show significant improvement over the F6F-3 even with combat power.
This graph shows a pretty good range of F6F performance both -3 and -5.
(http://www.wwiiaircraftperformance.org/f6f/f6f-level.jpg)
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Dave Southwood article that Wolfala sent me had some interesting observations in it. One of the paragraphs talked about the basic roll characteristics of serveral aircraft and so one night we tested the Hurri to see if Southwoods observations and the aircraft in the game were the same.
Quote: "However, the same [360 degree roll at 5,000 feet MSL] in the Hurricane at 200 KIAS takes 6 seconds to complete."
We tested the Hurri I and Hurri II in the game and using 220 MPH IAS, both aircraft completed both rudder assisted rolls (4 seconds) and unassisted rolls (4.5 seconds) faster than Southwood's article. Rolls were made to the left, to take advantage of the torque effect. Pretty big difference indeed, if the articles claims of the roll rate are correct. I looked on WWII performance for some roll rate information and couldn't find it. So, I have no idea if this is an issue or not.
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I think the hurri IIC's need to be looked at very closely. They seem to dive way to fast and maintain maneuvability at 400+. Many times I have seen and had a hurri dive down with me in my Hog and stay with me, even in a high speed turns. Its only the hurri IIC's.
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I had another couple of issues/questions:
1) In another thread, I asked about the nose up moment on all the aircraft when flaps are deployed. HT said that their was a moment created by flaps that pushed the nose based on the moments relation to the CG of the aircraft. Regardless, the P-47N POH states that flap deployment requires pitch trim to "counter the nose heaviness" after flaps are deployed. Just curious about the discrepancy there.
2) Second observation is whether or not the roll moment caused by aggressive rudder use is proportional. I know from my PPL training that dutch rolls are accomplished using nothing more than rudder, but they were very small. I've flown 5 different planes and even a 172, with its monstrous rudder, doesn't have a very severe roll moment with hard rudder movement. I have a very difficult time skidding AH aircraft without almost full opposite aileron control. Extreme slips mean a 90 degree attitude, with full opposite rudder. Again, I've never flown a WWII aircraft and have no idea what the comparitive rudder roll moment would be, but I know that the P-47 was not supposed to have a very effective rudder, and yet, in the game, I can roll the plane all the way over inverted with rudder alone. I suppose the roll stability of the aircraft has much to do with roll moment created by the rudder, so I though maybe one of the others more in the know, could explain this to me. Could this frustrate the hammerhead as well?
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Originally posted by MwDogg
I think the hurri IIC's need to be looked at very closely. They seem to dive way to fast and maintain maneuvability at 400+. Many times I have seen and had a hurri dive down with me in my Hog and stay with me, even in a high speed turns. Its only the hurri IIC's.
Hi,
its not only the Hurri, in AH the more light wingloaded planes in general tend to show this behaviour. The A6M5 but also the 109E, 109F, SpitV, F4F etc dive pretty good and keep energy like mad afterward. Much more powerfull planes with much more weight(inertia) lose much more energy while highspeed turns and vertical manouvers.
Imho this wrong e-bleed behaviour (specialy at highspeed) is the biggest mistake. This result into the superplanes F4U-4, Tempest, La7 and Spit16(all three rather light wingloaded and powerfull), while planes like the P51D, FW190D9, Spit14 and 109K4 imho dont fit into this line, if it comes to the energymanagemant at highspeed.
Similar it is A6M5 vs P40, 109F4 vs 109G, 190A5 vs A8, P38G vs P38L, SpitV vs SpitIXc or P51B vs P51D. The more heavy plane always lose much more energy even while very smooth highspeed manouvers, while the particular much higher inertia and/or power with similar or smaler drag should have the oposide result.
Actually iam not sure where exact the mistake is, no-power-deceleration-tests with a HurrIIc and FW190A8 show that the inertia and zero drag seems to be right(if both planes cut the throttle at 450mph, the Hurri decelerate MUCH faster), but with full power the FW190A8 have real problems to get rid of the HurriIIc. If the FW190A8 make smooth manouvers, the Hurri is able to stay on its tail(the A6M5 is or at least was similar) and a upzoom is hopeless so it seems to me that the MUCH stronger 190 engine dont count that much at highspeed(the P47, P38 and other planes have similar problems).
Strangewise in rare cases some planes show the right relation. For example the A6M2 lose much more energy than the A6M5, althought the last one is more heavy and have smaler wings.
I think the relative energy-bleed performences above Vmax need to get adjusted, then 10mph more or less dont count that much anymore(the behaviour while flying with full flaps also need to get more realistic).
Greetings,
Knegel
P.S.:It may be that some of my comparisons base on outdated experiences(one of the last updates particular changed things a lot), but general tendency is still the same with the current FM.
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Well the hog is actually a very heavy plane and should be able to hold its E very well, which in AH it does. At least for me. Empty weights for the -1 are about 10,300lb's (no ammo and near zero fuel). When fully loaded less ords, it weighs near 12,500lb's. The hurriIIc weighs what, 7000lbs approx loaded?
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I agree. In fact, I delight in throwing that very picture at the IL-2 fanboys every time they start gushing about IL-2 being the paragon of flight model realism (it is far from that). It usually shuts them up for a while.
So are you saying you have some other factual data on the IL-2 series that which you can compare with Pyro's pic, and find it severely lacking?
If otherwise, how in nine hells would you know which one is truly better?
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"Thoughts on the Current Flight Model"
Actually this seems to be concerning more flaws in individual models -not the flaws (or what ever) in current flight model .
Semantics, sry... :p
E.g. The inverted stall of a Spitfire is a "flaw" (not a major one) in current flight model and probably not a fault of some error in Spitfire model itself.
Well, how could I know for sure...
***
However my list of flaws in several models:
-Too low AoA limits of aircaft equipped with slats (I could be wrong but I have not seen any confirmation to other direction). This could affect some models unfavourably. I also seem to have been wrong in my statements in flap effects on AoA limits...
-Too weak wingtips of late FW series.
-Too slow spool time of 262 engines. The behaviour of 262 airframe is not logical. It does not want to accelerate even in dive and then it does not want to slow down. Or is it because of engine drag and inablity to slow down the turbine? The airframe should not provide much drag?
-Adamantium tail units (+5 resistance to 30mm) in Lanc and B24. (Both double rudders! Hmmm...)
-Wrong sights in German armour and probably in Allied armour too. Plus you can move your driver views outside of tank in some armour, at least in T34 and M8.
-Too small view from 109 cockpit. The view should be slightly wider. The same flaw is most prolly also in FW. You cannot see much of the outer framing if there is armour glass installed.
-Wrong AoA of FW. No evidence, just a hunch. 2 degrees of AoA added with changing profile incidence angle with speed should give more significant nose down attitude even at cruise.
-Too slow deck speed for FW190A8. It is pain to get it to 345mph and it should do 350 mph no probs. It does not seem to benefit of more power either when compared to A5. It should at least be able to accelerate faster. To me it seems that A5 dominates the A8 by a margin in a dogfight. Did they really make the A8 worse than A5 back then? :huh
-90 round Minengeshoss magazines for A5 outboard MG-FFs.
-Forward firing 20mm MG-FF for JU-88A4!
-C+
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Originally posted by Charge
you can move your driver views outside of tank in some armour, at least in T34 and M8.
-C+
Ummm you can do that with Tiger and panzer also.
Strange that you leave those out.
Wondering why you would, as they are German and I'm sure you have driven them.
(http://www.thesmilies.com/smilies/rolleye0010.gif)
Bronk
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I see I will be the zeke dork to address the zero dive FM.
Firstly neither of the zero's dive particularly well or for anything that could be considered a distance.. all models of the zero have a nasty habbit of nosing down and to the right at over 400mph below 10k and 455 at 15k.
This death dive and spin is and can be unrecoverable if the pilot is not familiar with recovery tactics.. and btw once in it she falls apart like a paper airplane.
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Originally posted by MwDogg
Well the hog is actually a very heavy plane and should be able to hold its E very well, which in AH it does. At least for me. Empty weights for the -1 are about 10,300lb's (no ammo and near zero fuel). When fully loaded less ords, it weighs near 12,500lb's. The hurriIIc weighs what, 7000lbs approx loaded?
Hi,
not only the weight is important, its the dragload that count and the Hog was one of the biggest single engine fighters in war, it should be able to keep its energy high rather due to its strong engine than due to its airframe.
Btw, the wingload is at least as good or a better value to estimate the e-bleed behaviour than to estimate the turnbehaviour.
The F4U was a rather light wingloaded plane, although the smal wing aspectratio tend to provide a better dragbehaviour at highspeed, it still have a rather big surface in relation to its mass(in comparison to the 190A/D, 109K, P51D, P38 and P47) and i doubt that the big engine was helpfull to keep the drag low.
Greetings,
Knegel
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Originally posted by Widewing
My issues related to the P-51B vs P-47 are also supported by Brit data that shows the Mustang III (P-51B) turns much smaller circles than the P-47. There is also testing at Eglin Field that supports the argument.
From http://www.wwiiaircraftperformance.org:
PROOF DEPARTMENT
TACTICAL COMBAT SECTION
ARMY AIR FORCES PROVING GROUND COMMAND, EGLIN FIELD, FLORIDA
FINAL REPORT ON TACTICAL SUITABILITY OF THE P-47C-1 TYPE AIRCRAFT
18 December 1942
1. OBJECT:
To determine the relative tactical value of the P-47C-1 type aircraft for combat service.
(snip)
3) Maneuverability -- The P-47C-1 was flown in mock combat against the P-38F, P-39D1, P-40F, and the P-51.
(a) It had superior rate of aileron roll at all speeds, and especially at high speed to all American fighter contemporary types, none could follow it in a fast reverse turn.
(b) The turning circle of this aircraft was larger than any of the other types engaged in combat. The high wing loading makes the plane mush in all maneuvers controlled by the elevators, and this also causes high speed stall in tight turns.
(c) It was slightly slower in acceleration from level flight at fifteen-thousand (15,000) than all types except the P-40F, which was decidedly slower, however, the distance gained in the initial acceleration was never greater than fifty (50) yards and the P-47C-1 rapidly overhauled and passed the other types. This test was with closed shutters and the liquid cooled engines rapidly overheated, the shutters had to be opened and the planes decreased a good deal in speed allowing P-47C-1 to run away rapidly. In push-overs with maximum manifold pressure the P-47 accelerated faster and drew away from all other types.
(d) In testing the zoom ability of the P-47C-1 it was found that from level flight and dives, the zoom was comparable with the P-40F. The P-39D1, P-38F, and P-51 have greater zooming ability.
(e) In close fighting the P-47C-1, due to its faster aileron roll, can quickly reverse turn and break off the combat almost at will. However, due to the large turning circle and low rate of climb, it is deemed inadvisable to attempt to dog fight with any type of enemy fighter now used in the combat area.
In short, the P-51B should run circles around the P-47D-11.
(http://www.wwiiaircraftperformance.org/wade-turning.jpg)
As to the stall behavior, I can stall an aircraft and it drops straight down without a hint of rotation. In the case of the Mosquito, it has 8,000 lb of thrust and the corresponding torque. Both are ignored and the aircraft has zero forward motion, while wings are level and without any rotation whatsoever. I have a real problem accepting that this is normal behavior, especially since this behavior was introduced with an update to the software and had not existed prior.
If P-factor is modeled correctly, I would think that there should be some slipstream impingement on the rudder. I don't see any. Which is why it is impossible to perform a true hammerhead stall.
My regards,
Widewing
Widewing & All..
You guys are wrong, you need to look at this data again. Your Compairing a P-47C-1-RE against a P-47D-11-RE. Tho they are simular in design your not taking in account the motors of the planes.
The P-47C-1 w/2800-21 - 2000hp and no water injection vs P-47D-11 with 2800-63 - 2300 hp which also had water injection.
It would be like comparing a A-36 Allison V-1710-81 to a P-51B Packard V-1650-3(Merlin made 68)
If were going to base this on facts lets have them right.
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Originally posted by Kweassa
So are you saying you have some other factual data on the IL-2 series that which you can compare with Pyro's pic, and find it severely lacking?
That's right.
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Ok it seems that some people here want increased boost for their favorite planes such as the Spit, P38, and P51. If that's the case then we should have Perk "power-up", similar to proposed Perk "Ordinance".
http://forums.hitechcreations.com/forums/showthread.php?s=&threadid=198125
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"Ummm you can do that with Tiger and panzer also.
Strange that you leave those out.
Wondering why you would, as they are German and I'm sure you have driven them."
Nice one Bronk. :)
Before you mentioned this I wasn't aware that you can stick you head through the roof of the drivers place -never even crossed my mind that you could do something like that (in Pz and Tgr). If it is meant to simulate the drivers exit hatch you should only be able to stick your head from where the hatch actually is, not though front plate. :p
-C+
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Originally posted by 1K3
Ok it seems that some people here want increased boost for their favorite planes such as the Spit, P38, and P51. If that's the case then we should have Perk "power-up", similar to proposed Perk "Ordinance".
You forgot the current 1.98 ata Me-109K. You meant to include that in the list, didn't you? You want that to be perked, too, right? Am I reading you correctly? Fair play and all?
You Luftwhiners always want to have your cake and eat it as well. If you want the U.S. and British ships to use standard boosts, than the Luftwaffe airplanes should definitely use the standard boosts as well. U.S. and British fighters used their higher boosts a lot more than their Nazi opponents.
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Benny you're so unable to post any data, you're boring.
Btw you still have no idea why the TsAGI PE2 data vs Rechlin data match ?
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If we get "perk performance" along with proposed "perk ordinance" players will see... (and if you have enough points you can select...)
+25 boost Spit XVI
+21 Spit XIV
150 grade fuel on P-51B and D
Higher boost P-38L
1.98ata 109K
Fw 190A-8 and F-8 with MW-50 for WEP
100/130 octane fuel for Ki-84, J2M3
P-47D-25 with 150 grade fuel (basically a P-47M)
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Originally posted by 1K3
If we get "perk performance" along with proposed "perk ordinance" players will see... (and if you have enough points you can select...)
+25 boost Spit XVI
+21 Spit XIV
150 grade fuel on P-51B and D
Higher boost P-38L
1.98ata 109K
Fw 190A-8 and F-8 with MW-50 for WEP
100/130 octane fuel for Ki-84, J2M3
P-47D-25 with 150 grade fuel (basically a P-47M)
It should only be a perk option if it existed and was in service. Not almost in service or not available at all (such as 100/130 avgas in Japanese fighters).
My regards,
Widewing
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Originally posted by 1K3
If we get "perk performance" along with proposed "perk ordinance" players will see... (and if you have enough points you can select...)
1.98ata 109K
We appear to already have a 1.98 ata Me-109K. If this is so, does that mean you support it being perked?
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Originally posted by nuchpatrick
Widewing & All..
You guys are wrong, you need to look at this data again. Your Compairing a P-47C-1-RE against a P-47D-11-RE. Tho they are simular in design your not taking in account the motors of the planes.
The P-47C-1 w/2800-21 - 2000hp and no water injection vs P-47D-11 with 2800-63 - 2300 hp which also had water injection.
It would be like comparing a A-36 Allison V-1710-81 to a P-51B Packard V-1650-3(Merlin made 68)
If were going to base this on facts lets have them right.
I guess you're stumbling over the relationships the test displays.
That P-47C was tested against a P-51A. Thus, the 300 lb lighter (than the P-51B) also has 390 less horsepower, and therefore a poor power loading compared to the P-47C. Nonetheless, the P-51A out-turns the Jug.
Moreover, I'm not comparing the P-47C to the P-51B at all...
Go back to the beginning and see if you can find where you lost the trail of my reasoning.
My regards,
Widewing
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Point 12 Stepanets and Roger Sauvage pretend the Yak 9T was able to dive at 850km.h-1 without any trouble.
It has been discussed in the past here and there was not any proof posted prooving the modelling wrong.
If I can get a hand on my caving helmet I'll try to post some scan.
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Originally posted by Charge
Actually this seems to be concerning more flaws in individual models -not the flaws (or what ever) in current flight model .
Semantics, sry... :p
I think we were originally using individual plane performance in the game and comparing it to real world examples in an attempt to discover where the flight model may need some tweaking. Widewing's original post shows that the last tweak to the model certainly changed the turn performance of the P-51 for the worse, much like the one previously developed the "last notch of flaps drag anchor" in the P-38. We're not looking at higher manifold pressures from higher octane fuel, or correct modelling of armament, merely the aerodynamic qualities of the aircraft in the game as opposed to their actual qualities in real life. Through this, we hope to determine if there are opportunities to better tweak the model to more closely approach the real life flight characteristics of the individual aircraft.
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Here's another one to the list...
(http://home.att.net/~c.c.jordan/TonyExcerpt.gif)
Our Ki-61 is a bit heavier then that tested, but not much. In the game, the Ki-61 doesn't even come close to turning with an FM-2. They are nearly 80 feet apart in turn radius.
Also, this is one of those fighters that suffered badly after the last drag model update. Flaps add massive drag, but little improvement in turn radius, while turn rate suffers badly.
You can find a complete copy of this Navy test on this website. (http://www.wwiiaircraftperformance.org/)
My regards,
Widewing
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Originally posted by Widewing
Also, this is one of those fighters that suffered badly after the last drag model update. Flaps add massive drag, but little improvement in turn radius, while turn rate suffers badly.
My regards,
Widewing
Hi,
maybe they did start in the Ki61 to model the flaps in a more realistic way?? :rofl
I hope they take the K61 flaps as base for comming updates. :aok
Greetings,
Knegel
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our AH ki61 has no problems staying with spits @ turns.
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Spit WEP -
The 5 mins was only a guideline laid down bt the Air Ministry.
They go on to say that if the 5 mins is exceeded it should be reported to ensure extra engine checks are carried out.
Max use of WEP in a Spit I am aware of was a Spit IX running home from 3 x 109s - he ran WEP for 35 mins.
The 5 min limit in AH2 is an 'artificial' block.
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Originally posted by Benny Moore
We appear to already have a 1.98 ata Me-109K. If this is so, does that mean you support it being perked?
We do? That's funny because the boost guage in mine only goes up to 1.80
As far as being perked goes, how do you perk a plane with an ENY of 20?
There are plenty of rides that are just as fast as a 109K, and plenty more maneuverable too. Perking, IMHO, is to keep large quantities of uber-planes from unbalancing the arenas.
Having a load of 109Ks coming into your base isn't exactly the same as having a bunch of Tempests (or La-7s for that matter) show up overhead. 65 x 30mm rounds, a couple of MGs and no ordinance isn't exactly earth shattering.
As fas as 1.98 ata goes, there's plenty of data out there to support the 2,000hp / 1.98ata 109K4 variants, and plenty of it has been posted here.
EagleDNY
$.02
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Originally posted by EagleDNY
As fas as 1.98 ata goes, there's plenty of data out there to support the 2,000hp / 1.98ata 109K4 variants, and plenty of it has been posted here.
EagleDNY
$.02
Theres plenty of graphs, the often cited intention to swap K-4 units to 1.98ata (end Mar 1945), but nothing ever showing even one was used operationally at 1.98ata.
Equivalent would be the intention to boost some Spits to 30lbs,
Intention - yup,
Was it tested (there are graphs) - yup
Ever used operationally - no.
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Wow. As I said, you Luftwhiners just love to have your cake and eat it as well. You say of the Me-109, "There are plenty of rides that are just as fast as a 109K, and plenty more maneuverable too. Perking, IMHO, is to keep large quantities of uber-planes from unbalancing the arenas." And yet you would want a 66" P-38 perked, although the same statement would apply. There are plenty of rides that are just as fast as a 66" P-38, and plenty more maneuverable, too.
You think that there's nothing wrong with having a 1.98 ata Me-109, yet do not want to see a 75" P-38 (or even a 66" P-38). That's called a double standard if I ever heard one. 1.98 ata was used less on the Me-109 than the 70 and 75 inch ratings on the P-38L, but you have no problem with this little-used rating being in the game but you balk at the thought of the common, officially approved 66" rating on the P-38. That's hypocrisy.
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Originally posted by Benny Moore
Wow. As I said, you Luftwhiners just love to have your cake and eat it as well. You say of the Me-109, "There are plenty of rides that are just as fast as a 109K, and plenty more maneuverable too. Perking, IMHO, is to keep large quantities of uber-planes from unbalancing the arenas." And yet you would want a 66" P-38 perked, although the same statement would apply. There are plenty of rides that are just as fast as a 66" P-38, and plenty more maneuverable, too.
You think that there's nothing wrong with having a 1.98 ata Me-109, yet do not want to see a 75" P-38 (or even a 66" P-38). That's called a double standard if I ever heard one. 1.98 ata was used less on the Me-109 than the 70 and 75 inch ratings on the P-38L, but you have no problem with this little-used rating being in the game but you balk at the thought of the common, officially approved 66" rating on the P-38. That's hypocrisy.
Usually the same guys who say if there was a 4 cannon 1943 Spit Vc it should be perked :) .
Probably would ask for a mid 43 spit XII to be perked also.
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Originally posted by Kev367th
Usually the same guys who say if there was a 4 cannon 1943 Spit Vc it should be perked :) .
Probably would ask for a mid 43 spit XII to be perked also.
Well that 5 min of wep is SOOOOOOOOOOOOO unbalancing.
:noid :noid :noid :noid :rolleyes: :rolleyes: :rolleyes:
Bronk
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Wow. As I said, you Luftwhiners just love to have your cake and eat it as well. You say of the Me-109, "There are plenty of rides that are just as fast as a 109K, and plenty more maneuverable too. Perking, IMHO, is to keep large quantities of uber-planes from unbalancing the arenas." And yet you would want a 66" P-38 perked, although the same statement would apply. There are plenty of rides that are just as fast as a 66" P-38, and plenty more maneuverable, too.
Right, so both should be perked.
You think that there's nothing wrong with having a 1.98 ata Me-109, yet do not want to see a 75" P-38 (or even a 66" P-38). That's called a double standard if I ever heard one. 1.98 ata was used less on the Me-109 than the 70 and 75 inch ratings on the P-38L, but you have no problem with this little-used rating being in the game but you balk at the thought of the common, officially approved 66" rating on the P-38. That's hypocrisy.
I'd be careful before you proceed into any more typical name-calling and side branding, because there are many different opinions on just what kind of perk policy should be adhered to by all kinds of people, including both Luftwaffe fans and USAAF fans.
So far, it is about established that every post and thread has been degenerated into somekind of typical mud slinging between the fans, and not all of them were perpatrated by the Luftwaffe fans. You have this incredibly judgemental and deterministic attitude in regards to opinions that differ from yours and seem to have no reservations in stamping the clasic "Luftwhiner" brand to everyone who would oppose. Frankly, that makes you really no different from some classic riot-acts like Kurfurst, to our eyes.
Concerning the comparative status of the two different planes; the Me109K-4 and the P-38, in regards to boost levels and perks, there has already been discussions and posts explaining why some boost levels are left out of the game, which for some reason you seem to just not listen to. Personally I believe our K-4 is running at 1.98, but it is still controversial. Likewise, ratings over 66" in the P-38L is equally controversial and currently there is no solid evidence that warrants its use in the game (except some abominable snowman of a memoranda you claim to have seen somewhere, but still remains to be actually presented) according to HTC's (presumed) guidline in aircrafy modelling standards.
So I suggest you take all of that into account, before making a mess of things which would make a lot of people frown.
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I have not yet found it, but I have found someone who had it. In the meantime, here are two other people mentioning it on two different forum. On one, there is the text of a memorandum, and on the other there is a dead link to the scanned document. This, of course, proves nothing, except that I am not making this up. I'll continue searching for the actual scan of the document.
http://home.epix.net/~cap14/p38wep.jpg
MW was kind enough to scan this in for us...I thought I'd post it over here too.
War Emergency Ratings were raised from 60" to 66" with the advent of higher octain fuel.
My guess is that the P-38L started to delver on June of 44 the same month this fuel became available. So the advisory circular came after the POHs were published for the 38L.
Here is the snippet MW gave us: "P-38Js were cleared for a WER limit of 66" Hg using 150 grade fuel. The entire 8th AF fighter component switched over to 150 octane in early June 1944. No modifications to the P-38's were necessary to run at the higher limits, however it was suggested that using AC433M spark plugs was advisable."
Notice they suggest an increase of 25 MPH of speed and 800 FPM in climb below 20K.
Nice work, mw.
Worr, out
A US Air Corps. memorandum from the Chief, Petroleum Section to the Chief, Supply Divison, US Army dated 11 July, 1944, Subject: Grade 150 Aviation Fuel:
The following limiting War Emergency Rating Manifold Pressures have been established by the Eighth Air Force for the different aircraft:
Aircraft------------Old W.E.R.------New W.E.R.
P-38J---------------60"-------------66"
P-47D without water-52"-------------62"
P-47D with water----57"-------------67"
P-51B---------------67"-------------72"
It is thought that the above manifold pressures may even be increased to some extent using 150 Grade fuel, and roughly speaking the increase in speed of fighter aircraft at altitudes below 20,000 ft. is approximately 25 miles per hour. The increase in the rate of climb is approximately 800 ft. per minute. In addition, manifold pressures can be used at the higher ratings without danger of incipient detonation; this gives a greater factor of safety.
http://forums.ubi.com/eve/forums/a/tpc/f/63110913/m/2761038533/p/9
http://bbs.warbirdsiii.com/showthread.php?postid=35121
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Hiya Benny:
Have a look at these when you get a chance:
Flight Tests of Fighter Aircraft with 44-1 Fuel (http://www.wwiiaircraftperformance.org/150grade/engdiv-16-march-44.jpg) 75" MAP for P-38J
Preliminary 7-1/2 Hour War Emergency Rating Test of the Allison V-1710-91 (http://www.wwiiaircraftperformance.org/150grade/p-38-75inch-prelim-wer.jpg)...
"The Allison V-1710-91, No. A-047669, satisfactorily completed a 7-1/2 hour preliminary War Emergency Approval Test at a rating of 2000 b.h.p. at 3000 r.p.m. and 75 inches manifold pressure as conducted."
Preliminary Flight Tests of Fighter Aircraft Using PPF 44-1 Fuel at Increased War Emergency Ratings. (http://www.wwiiaircraftperformance.org/150grade/eng295.jpg)
"Based on these preliminary flight tests, it is concluded that satisfactory operation is experienced on the P-47D airplane ar 65" M.A.P., on the P-51B airplane at 75" M.A.P., and on the P-38J airplane at 70: hg. M.A.P., except in the case of the P-47D airplane in extended climbs with water injection."
Flight Tests on the Lockheed P-38J Airplane, AAF No. 43-28392 Using 44-1 Fuel (http://www.wwiiaircraftperformance.org/p-38/p-38-28392.html)
P-38J Airspeed Comparison Grade 104/150 Fuel (http://www.wwiiaircraftperformance.org/150grade/p38-eglin-level.jpg)
Techical Instructions. CTI-1659. Modification of Fighter Aircraft for use of Grade 150 Fuel (http://www.wwiiaircraftperformance.org/150grade/cti-1659.pdf)
Project P.P.F. Final Release approving 70" MAP for the P-38 (http://www.wwiiaircraftperformance.org/mustang/ppf-20june44.pdf)
150 Grade Aviation Fuel (http://www.wwiiaircraftperformance.org/mustang/supplymemo-11july44.pdf) 66" MAP established by the 8th AF as new WER rating for the P-38J
I probably missed some. Check also:
WWII Aircraft Performance (http://www.wwiiaircraftperformance.org/)
P-38 Performance (http://www.wwiiaircraftperformance.org/p-38/p-38.html)
100/150 Grade Fuel (http://www.wwiiaircraftperformance.org/150grade/150-grade-fuel.html)
Of course its quite clear that the USAAF and the 8th cleared the P-38 for MAP greater than 60". I figure the 479th is probably the best bet to find documentation of operational use of boost in excess of 60" for the P-38J. I've put that on my to-do list ;)
Mike
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Thank you very, very much! I've been trying to get my hands on those again for years now. How do you find this stuff, do you live in the National Archives?
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Originally posted by mw
Of course its quite clear that the USAAF and the 8th cleared the P-38 for MAP greater than 60". I figure the 479th is probably the best bet to find documentation of operational use of boost in excess of 60" for the P-38J. I've put that on my to-do list ;)
Mike
Mike, I want to thank you and Neil Sterling for putting up one of the most valuable aviation history websites on the web. I have posted many links to the documents you have put up and will continue to do so.
So many people will benefit from your hard work, from aviation sim fans, to historians and aviation buffs.
We, as a community, owe you guys a debt of gratitude.
My regards,
Widewing
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Is there any information of how widely the 66" or 75" boost was taken into use in active squadrons as there were modifiations which needed to be done first?
-C+
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The modifications involved simply changing a governor. Allison representitives went throughout the squadrons in Europe showing them how to do this.
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Boost governor? Doesn't sound like a biggie...
BTW what is the WEP kit for P-47 that the inreased boost and 150g fuel made unnecessary?
-C+
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Wow. Great stuff MW. Bring on the 70" P-38!! One thing that caught my eye from the P-38 performance link regarding the relative turning ability of the 38F and G:
"The P-38G turns much better than the P-38F (will close 180 degrees in 360 degree circle) due to maneuver flaps."
Something to consider for those that think the 38's "magic" fowler flaps work too well in the game.
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Hiya Widewing:
Thanks so much for the kind words. Neil and I are proud of the work we've done and very pleased that folks such as yourself find the material on the site to be interesting and of value.
Benny Moore & DblTrubl; no problem. I'm glad we could help out. :)
Mike
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Hi,
in a US fighter comparison from October 1944 they use the 2600HP as WEP for the P47D, 2410HP WEP for the F4U-4, but only 1600HP WEP for the P38J, while the P51B is listed only with military power(1510HP).
This indicate that the higher rating for the P38 wasnt normal, but for the P47, though the performence of the P47 is what we have now in AH.
Btw, our P38L already reach 345mph @ sea level, thats already 10mph more than the test display with 60", so our P38L already seems to use 65".
Greetings,
Knegel
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Which document is that? I'll check it out.
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Originally posted by Knegel
Hi,
in a US fighter comparison from October 1944 they use the 2600HP as WEP for the P47D, 2410HP WEP for the F4U-4, but only 1600HP WEP for the P38J, while the P51B is listed only with military power(1510HP).
This indicate that the higher rating for the P38 wasnt normal, but for the P47, though the performence of the P47 is what we have now in AH.
Btw, our P38L already reach 345mph @ sea level, thats already 10mph more than the test display with 60", so our P38L already seems to use 65".
Greetings,
Knegel
The P-51D (not B) tested at the 1944 Fighter Conference is rated at 1,595 hp @ 67 in/hg.
The P-38J was not tested, but the P-38L was tested. 1,600 hp @ 60 in/hg.
I don't see any test data in the Conference report, only personal observations.
You need to look at this document (http://www.wwiiaircraftperformance.org/p-38/p-38-67869.html). Here the speed at sea level for the P-38J is defined as 345 mph @ 60 in/hg, and the engines were making less than full rated power.
(http://www.wwiiaircraftperformance.org/p-38/p-38j-67869-level.jpg)
Our P-38J conforms dead-on to the above chart.
My regards,
Widewing
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That makes sense, Widewing. Knegel, I would like to see where you came up with that. Moreover, there's another problem with what you say. One of the documents gives a speed increase of approximately 25 M.P.H. below 20,000 feet when going from 60" to 66". That does not match up with your 10 M.P.H. gain when going from 60" to 65".
I'll do some more looking through various sources. Really, though, I think that Widewing is right (as usual).
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Originally posted by Kev367th
Theres plenty of graphs, the often cited intention to swap K-4 units to 1.98ata (end Mar 1945), but nothing ever showing even one was used operationally at 1.98ata.
Equivalent would be the intention to boost some Spits to 30lbs,
Intention - yup,
Was it tested (there are graphs) - yup
Ever used operationally - no.
I don't know about that - the link from the kurfurst site (below) has the translated german documents showing that 1.98ata was used in operational units before the end of the war.
See:
Kurfust Site (http://kurfurst.atw.hu/articles/MW_KvsXIV.htm)
Admittedly, it looks like these would have been extremely limited in number as it looks like they needed C3 fuel with the MW50 system to get to the 1.98 ata level and not have the motors explode. I doubt there were more than a few units that actually set their 109Ks to 1.98ata and flew combat sorties in them, probably because of the serious shortage of the higher octane C3 fuel if for no other reason.
I didn't used to think that the B4 vs C3 fuel difference was that great an issue until I read the JG26 history. In it, a 190D9 pilot tells about running out of fuel during operation bodenplatte: he put down at a 109 field (III/JG6) - which only had B4 fuel, and he was stuck there until they sent him over a drum of C3. I'd have thought you could have dropped 55 gallons of 87 octane in the tank for a short, low alt hop back to your home field, but I guess that wasn't the case.
Are there luftwaffe docs that specifically state the "hpt schmidt went up in a 109k4 cleared for 1.98ata" - not that I've seen, but the translated docs on the site above sure convinced me that 1.98 was cleared and in operational use before the end of the war. Given the shortage of C3 fuel, and that the 190D9 units needed all the C3 they could get, I can see why there were only a few 109 units running on it.
The few units still using the 109 in '45 were slated for conversion to jets, so the 109K4 1.98ata would've been the last model to see action. I'd like to AH go to the 1.98 on the K4, if for no other reason than it gives the game the "final version" of the 109.
EagleDNY
$.02
Edit: the Kurfurst site's operator seems to have a personal beef with Mike Williams, which I have no basis to comment on. The sites translated documents are the only things I was interested in.
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The only operational use that can be shown is the couple of groups of G1-0 who were using it for "operational testing".
Nothing has yet come to light showing even 1 K-4 used 1.98ata, unless you allow for "we can safely assume" etc.
Look at -
OKL, Lw.-Führüngstab, Nr. 937/45 gKdos.(op) 20.03.45
Go throught the units, see how many got the K-4 out of the proposed ones listed.
Remember this is barely 1/2 - 2 months before the end of the war in Europe.
Then ask yourself how likely was it?
Note the word 'anticipate', which is then skewed into the word 'order'.
Look at the earlier part referencing the D-12, yup that happened then.
They definately intended to use 1.98ata, but nothing that proves they actually did.
If your reasoning is just to get the final version, then theres no reason not to have a -
21lbs Spit 14 (final version)
25lbs Spit 16 (final version)
Both of which have solid evidence (i.e. sqn logs), showing it was used.
Or the Ponys, 38's and Jugs with their final highest boost version.
Or how about a 25lbs Mossie?
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EagleDNY, that Kurfurst site is by Kurfurst, also know as Isegrim. He is a practiced and accomplished liar. If you really want, I can make and post a list of threads proving it.
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Hey Benny,
can you please stop that rubbish?? I never saw Kurfi lie, if what he do is to tell a lie, then you be a liar as well!!
When people write "we can assume" or "all know" or "its well known" its a generalation, but not a lie. Many people use this polemical technique including yourself. The Spitperformence testing page use similar polemical tactics. People who are big fans of a special plane simply have problems to stay objective, all who read should know that.
For now i dont found a hint that the datas on Kurfis page got changed or are wrong, a assumption always include the possibility of a failture, if a reader dont consider this, its not Kurfis fault!!
Widewing,
The P-51B (not D) tested at the 1944 Fighter Conference is rated at 1,510 hp @ 67 in/hg.
The P-38L was not tested, but the P-38J was tested. 1,600 hp @ 60 in/hg.
Anyway, here is the comparison i was refering to:
(http://www.raf-roy.com/share/knegel/Screenes/MSWF4UDATA_05_0001.jpg)
(http://www.raf-roy.com/share/knegel/Screenes/MSWF4UDATA_08_0001.jpg)
(http://www.raf-roy.com/share/knegel/Screenes/MSWF4UDATA_04_0001.jpg)
Greetings,
Knegel
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Originally posted by Knegel
Hey Benny,
can you please stop that rubbish?? I never saw Kurfi lie, if what he do is to tell a lie, then you be a liar as well!!
Kurfurst said that Big Kahuna made up numbers and lied to Oleg Maddox to get a P-38 that never existed. All three points are blatant lies, and he knew it. He never posted a bit of proof for any of them. I'll call him a liar if I please, and if you think me a liar also for saying so, then so be it. It does not matter to me what one thinks who considers Kurfurst anything like an honest man.
I've also seen him admit that the Me-109K was overmodelled in the IL-2 series, when talking to another 109 lover. However, when someone else suggested that the climb rate be corrected, Kurfurst claimed that it was fine and he never said it wasn't, which was two bold-faced lies at once.
It seems that I need to do a miniature research paper on Kurfurst's lying habit. I'll return with a list, compete with links. Maybe that will convince you. Unless maybe you also think it's okay to slander folks who have gotten data from books and wartime documents, by stating falsely that they fabricated thedata and lied to the developer. Kurfurst is a wicked man, and I do not envy him.
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Hm, in what way he lied to Oleg maddox?? You say that, but thats only rumor.
That he thought Big Kahuna made up numbers was what he thought, thats not a lie. That Kurfi is particular badly biased when he start to discuss about 109s i saw, you actually behave in the same way regarding P38´s and US planes in general, but i never saw him lie while that. He assume a lot and he dont accept many good arguments, but i never saw him stating selfmade datas etc.
Oleg Maddox isnt a little child, he know rather good what datas he accept, i realy doubt that Kurfi, who dont realy count as P38 expert, is able to influence Oleg Maddox regarding this plane. There was others with much better odds (Better conection to Maddox or his FM maker) to influence the resulting FM´s.
Btw, my main point is: Noone should talk bad about someone who cant take part of a discussion and specialy not if there is no proof.
Greetings,
Knegel
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Originally posted by Knegel
Btw, my main point is: Noone should talk bad about someone who cant take part of a discussion and specialy not if there is no proof.
Or better yet, lets get back on topic. Start a new thread for your boost/aircraft/liar, liar, pants on fire debate.
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Knegel
Twisting info to fit your agenda is dishonest.
Like kev said he would present field testing data of 1.98 ata as "widely used".
That is being dishonest.
Sorry if we disagree on this. But if a person can not be taken as honest, when they use good info this way.
Bronk
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Ok - this is my last go round on the 1.98 ata subject, since I think we are getting off topic here.
Again, I can't dispute that there isn't any direct documentation where we see some luftwaffe mechanic noting that so and so's 109 has been set to 1.98 ata. Given the state of the luftwaffe at the end of the war, it isn't surprising to me that a lot of gruppe level documents would be lost / destroyed as the units are being disbanded, destroyed, or retreating, and the type of documents we are talking about are about the last things most historians at the time would give a damn about, even if they avoided destruction as the units retreated.
The kurfurst site has the one document that shows that the LW high command did issue orders to boost to 1.98ata on March 20, '45 - I did a quick lookup on the JG27 and JG53, which Kurfurst cites as operational 109K units that received this order.
III. JG53, which had 109Ks, was operational until May 8, '45.
IV. JG53, also 109Ks, was operational until April 30, '45.
I. and III. JG27, also 109Ks, were operational until May 8, '45.
Given, these units would have been in a sorry state in March - April, '45 but unless they are given to ignoring orders from the high command, they were ordered to boost to 1.98, and they were flying sorties after that order was given. Did they obey the order? I don't know. Did they have C3 fuel to allow the birds to fly at 1.98 even if they wanted to? I don't know.
The 109 fans can't produce the volume of USAAF or RAF docs that show that plane type x flew at boost level y (aren't bureaucracies wonderful?), but given that we have an order issued to operational units, I think the inference that some 109s flew at 1.98 is a fair one.
For the game, all that 1.98 means is that the 109K would be climbing faster and would have better acceleration and a higher top speed. Frankly, having flown the thing quite a bit, the extra power is probably as dangerous to the pilot as it is to his target. More engine power in that airframe doesn't fix its flaws, and it is easy to turn the 190K into a lawn dart already.
Can we find other rides in the game where the boost, flight model, ord loadout, etc. could probably be adjusted and improved - sure. Does this mean that we shouldn't look to improve the 109s, I don't think so, but I'll leave off it here and start a 109 thread to pose my next questions.
EagleDNY
$.02
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Originally posted by Knegel
Widewing,
The P-51B (not D) tested at the 1944 Fighter Conference is rated at 1,510 hp @ 67 in/hg.
The P-38L was not tested, but the P-38J was tested. 1,600 hp @ 60 in/hg.
I'm looking at my copy of the Report of the Joint Fighter Conference, 16-23 Oct 1944 and there is no reference to testing the P-51B or P-38J, both of which were out of production at the time of the conference. At this event, they tested the P-51D and P-38L.
The data you have posted is from Vought, not from the Fighter Conference. I have a copy of the Vought report courtesy of F4UDOA.
My regards,
Widewing
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"The 109 fans can't produce the volume of USAAF or RAF docs that show that plane type x flew at boost level"
It seems that there is no document showing how wide spread the boost increase was in USAAF. Benny claims that the conversion was easy- all right, but to what extent were they completed and when?
We at least have that one document from Kurfy which shows which units used the 1,98ATA setting. It would be nice to see such document from USAAF to get a picture how well the conversions were done since the 150 octane and conversion approval were released.
Not that it has anything to do with the fact that US planes could withstand the increased boost and that K4 could use 1,98 ATA given C3 and proper spark plugs and that is enough to me to make them run with those boost levels in game because technically they were up to it.
-C+
Ps. "Like kev said he would present field testing data of 1.98 ata as "widely used". That is being dishonest."
I dont think so. That is just his biased opinion. Doesn't make him a liar.
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Originally posted by Charge
I dont think so. That is just his biased opinion. Doesn't make him a liar.
That's your bias opinion.
My bias opinion he couldn't make an honest argument.
Bronk
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Originally posted by Knegel
Hm, in what way he lied to Oleg maddox?? You say that, but thats only rumor.
That he thought Big Kahuna made up numbers was what he thought, thats not a lie.
No, no - Kurfust said that Big Kahana lied to Oleg. These were his exact words; "Kahuna lied to Oleg about the P-38." Don't tell me that Kurfurst "thought" that Big Kahuna made up numbers. Kahuna was very clear about where his numbers came from. And Kurfurst didn't say, "Kahuna may be making this up." He said, "Kahuna made these numbers up," and he said "Kahuna lied to Oleg." And he didn't say, "There's no evidence that the P-38 ran higher than 1600 hp.," he said, "The P-38 never ran higher than 1600 hp." All three points were previously disproven before ever he made those claims, all three of them are disgusting lies (two of them slanderous and libellious), and not one of them did Kurfurst provide one bit of support for. The man's a foul liar, and if you think he's honest you are not much better. I don't care if you think I don't have the right to accuse him; the threads speak for themselves. There is proof. I feel no reason to treat that liar with any respect and I certainly won't say nothing to his ugly accusations of a good guy. Big Kahuna is to the IL-2 community what Widewing is to ours.
"Knegel made up those numbers for the Me-109. The Me-109 never ran at 1.98 ata. Knegel lied to hitech." If I said that, would you still say, "He thought Knegel made up numbers was what he thought, thats not a lie"? If someone makes bold, nasty accusations like that, then he had better be able to provide some evidence, quick-smart!
Kurfurst's statements were not true, he was given no reason to make them, and he gave no evidence to support them. He repeatedly made serious unfounded allegations, not once backing them up. You can't say something nasty and untrue about someone, never back it up one bit, and still call yourself honest.
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Originally posted by EagleDNY
Ok - this is my last go round on the 1.98 ata subject, since I think we are getting off topic here.
Again, I can't dispute that there isn't any direct documentation where we see some luftwaffe mechanic noting that so and so's 109 has been set to 1.98 ata. Given the state of the luftwaffe at the end of the war, it isn't surprising to me that a lot of gruppe level documents would be lost / destroyed as the units are being disbanded, destroyed, or retreating, and the type of documents we are talking about are about the last things most historians at the time would give a damn about, even if they avoided destruction as the units retreated.
The kurfurst site has the one document that shows that the LW high command did issue orders to boost to 1.98ata on March 20, '45 - I did a quick lookup on the JG27 and JG53, which Kurfurst cites as operational 109K units that received this order.
III. JG53, which had 109Ks, was operational until May 8, '45.
IV. JG53, also 109Ks, was operational until April 30, '45.
I. and III. JG27, also 109Ks, were operational until May 8, '45.
Given, these units would have been in a sorry state in March - April, '45 but unless they are given to ignoring orders from the high command, they were ordered to boost to 1.98, and they were flying sorties after that order was given. Did they obey the order? I don't know. Did they have C3 fuel to allow the birds to fly at 1.98 even if they wanted to? I don't know.
The 109 fans can't produce the volume of USAAF or RAF docs that show that plane type x flew at boost level y (aren't bureaucracies wonderful?), but given that we have an order issued to operational units, I think the inference that some 109s flew at 1.98 is a fair one.
For the game, all that 1.98 means is that the 109K would be climbing faster and would have better acceleration and a higher top speed. Frankly, having flown the thing quite a bit, the extra power is probably as dangerous to the pilot as it is to his target. More engine power in that airframe doesn't fix its flaws, and it is easy to turn the 190K into a lawn dart already.
Can we find other rides in the game where the boost, flight model, ord loadout, etc. could probably be adjusted and improved - sure. Does this mean that we shouldn't look to improve the 109s, I don't think so, but I'll leave off it here and start a 109 thread to pose my next questions.
EagleDNY
$.02
Is it an order though, or a document of what they would like to do?
Even he states it is proposed changes.
Given that the LW was having to re-assign non essential fuel (including training and testing) to frontline units to come close to keeping sorties close to consistent from Jan 45 onwards, where does the extra C3 needed for 1.98ata come from, considering the 190s had to have it.
Or does it make more sense to leave things as they are, were the K-4's can use B4 or C3.
Should add also - did the ever get the plugs required for 1.98ata?
My main gripe - He said it took the RAF some 2 months from a clearence or order for a mod for it to start happening (look at the Spit I boost thread), yet quite happily asserts that in Germany 2 months from the end of the war some 76 K-4's were converted in those 2 months.
Funny how double standards crop up time and time again.
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Continuing with the original theme of this thread, if we look at the AFDU tests of the Tempest Mk.V (found here) (http://www.spitfireperformance.com/tempest/tempestafdu.html), we see that its performance in the game is better than displayed in real world flight testing.
A second document, that sheds additional light on this issue, can be found here. (http://www.wwiiaircraftperformance.org/tempest/tempest-V.html) Our Tempest pulls almost 10.5 lbs of boost. However, the test data shown in the above document states that this boost level resulted from using 150 octane avgas, not standard 130 octane. Thus, my question to HTC is: Is the Tempest modeled with 150 octane fuel?
In the AFDU test, the Tempest flown was the third production aircraft that used the longer Hispano Mk.V cannon and the engine never produced full boost. The document shows speeds corrected for the full 9.0 lb boost.
The charts below reflect 8.7 lb boost.
(http://www.spitfireperformance.com/tempest/jn731level.jpg)
(http://www.spitfireperformance.com/tempest/jn731climb.jpg)
My regards,
Widewing
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Here's actual climb and boost data taken from the game while recording climb rate at 1,000 foot increments during climb. Also shown is boost at the same altitudes. Data is provided for full load and 25% fuel.
(http://home.att.net/~c.c.jordan/TempestPerformance.jpg)
My regards,
Widewing
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Wow, it's nice to see others have developed an interest in this subject. MW and Neil really have unconvered a treasure trove of data, all of which supports the idea that all of the 8th AF FC groups switched to 150 octane, raised their boost levels, and continued to operate in this manor until V-E Day.
Originally posted by Charge
It seems that there is no document showing how wide spread the boost increase was in USAAF. Benny claims that the conversion was easy- all right, but to what extent were they completed and when?
While there isn't any one document that specifically describes the boost modifications carried out by each unit, keep in mind that nearly every mention of supplying 150 octane fuel to the 8th AF, right from the start, also mentions the performance increase that the fighters will get from it, and in some cases the increased boost levels that will be used to achieve this. It's pretty clear that everyone understood the goal of supplying 150 octane fuel was to raise boost levels on the aircraft. It's also clear that in the USAAF in the ETO, only the 8th FC ever used 150 octane (there are a couple of quotes floating out there talking about Mustangs at Iwo Jima using higher octane and higher boost, but I've never seen anything else on that).
There are documents stating that 150 octane fuel was supplied to and used by every 8th AF Fighter Command unit, and that it replaced the old 100/130 octane. There are documents stating what the new approved boost levels were with 150 octane fuel. There is a document describing the procurement of conversion kits for 8th AF fighter aircraft to allow the higher boost levels. There is a document describing how all the replacement fighter aircraft being processed by the 8th AF were being modified to use 150 octane. There are documents from the 78th and 359th fighter groups describing modifying their aircraft. And there are statements from pilots of the 20th, 353rd, 357th, 361st, 364th, and 479th fighter groups describing the use of 70" or more manifold pressure (all of these were in Mustangs). There are also pictures of 78th, 353rd and 357th FG aircraft remarked for 150 octane (and you would generally think that if the crews took time to repaint the placard, they would probably make the necessary boost mods as well), and a picture of a 352nd FG P-51 being fueled from a truck marked 150 octane.
All of that can be found on MW and Neil's web site. Here is a breakdown of the 8th AF's fighter units, what they were flying in June of '44 when 150 octane fuel came on the scene, and when they converted to other aircraft:
4th FG: P-51 from June 44 to May 45
20th FG: P-38 until July 44 - converted to P-51
55th FG: P-38 until July 44 - converted to P-51
56th FG: P-47 from June 44 to May 45
78th FG: P-47 until Dec 44 - converted to P-51
339th FG: P-51 from June 44 to May 45
352nd FG: P-51 from June 44 to May 45
353rd FG: P-47 until Oct 44 - converted to P-51
355th FG: P-51 from June 44 to May 45
356th FG: P-47 until Nov 44 - converted to P-51
357th FG: P-51 from June 44 to May 45
359th FG: P-51 from June 44 to May 45
361st FG: P-51 from June 44 to May 45
364th FG: P-38 until July 44 - converted to P-51
479th FG: P-38 until Sept 44 - converted to P-51
So we can see that of the 4 P-38 FGs in June, 3 groups used the 150 octane and higher boost settings for about a month, and 1 group for about 3 months.
The P-47s enjoyed a longer run with high boost. Of the 4 P-47 FGs in June, 1 used the 150 octane for about 4 months, 1 for about 5 months, 1 for about 6 months, and 1 until VE day.
The P-51s got the most benefit, with 7 fighter groups using 150 for the entire period, and all but one of the remaining groups converting to P-51s within the next 6 months.
For those not familiar with USAAF organization, a group would typically put up about 50 aircraft on one mission (generally 3 squadrons of 16 plus a few spares). Doing the math, this means that 8th FC could (and often did) put up 700 or more high boost Mustangs on a single mission, and for shorter periods of time at their peaks, 200 + high boost P-47s or 200 + high boost P-38s. Obviously the 47's and 38's weren't super common in this configuartion.
But consider that only around 400 N1K2s were ever built at all (taken from Francillon), or that in early 1945 only 398 La-7s were in frontline units and only 291 of those were combat ready (from Gordon & Khazanov), or that on the 31st Jan 45 the Luftwaffe only had 314 109K-4s available in it's frontline units (from Kurfurst's site). Or consider some of the extremely rare perk planes like the Ar234, Me163, Me262, Ta152 etc.
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Hi Widewing,
why the Temp with more weight climb better in your graph(blue/red line)??
What boost the Temp did use below 5k to archive the displayed climb down there??
I didnt know there was something called "fighter conference", if you have the Vaught docus, you should have known to which comparison i was refering to.
Anyway, the P38J and P51B was absolut common fighters till the end of war and absolut not outdated in oct.44. According to Bennys guess the usage of a higher presure as WEP was common in October 44 also for the P38J, since it seems that also the new P38L only got tested with a WEP of 60", while the P47D got its 2600HP i only can guess that at this time the 66" or higher boost dont got widely used in P38´s.
For now i only did read about the few recon P38L´s in Europe, using the higher boost, similar to the V1 intercepting planes.
Benny,
i still dont saw a proof that Kurfi did lie. He was probably wrong, when he thought Big Kahuna(is this the Big Kahuna who former did play EAW??) lie to O M, but that dont make him to a liar. A liar know that he is wrong, while Kurfi simply tend to overreact when he start to discuss. His fault was to assume that Big Kahuna lie and of course to speak this out loud, and even more bad this get, when this assumtion get proven as wrong. I absolutly agree to you here, but thats actually what you do as well!!
You only assume that Kurfi did lie!! You could call him deaf for oposide arguments, or badly biased due to a selective blindness, wishfull thinking, not nice(i bet he play rock´n roll), to have bad manners, constandly overreacting etc, thats the normal behaviour of many enthusiasts/fanatics, including you, but all this isnt a lie and this dont make the datas on his page or his page bad in general!!
He got banned for his behaviour from this board, to use the same bad manner to try to devaluate his page by calling him a liar simply is like to throw the helve after the hatchet.
Actually i only was up to inform you that your reputation dont get better by using the same manner, like Kurfi, and same like Kurfis behaviour is contraproductive for the 109 datas, also your behaviour make Kurfi rather more credible, cause most "normal" people simply tend to be mistrustful regarding fanatics and extreme enthusiasts, but of course its up to you.
Greetings,
Knegel
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Hi Sable,
the question is to what boost the P38 and P51 could(was allowed to) use with 150 octane fule on their long range missions?
Since two US fighter comparisions from okt.44 show the P38 with only 60" and the P51´s with only 67" heading, while the P47D and F4U-4 got the higher boost, i only can guess there was a good reason for this.
At least it dont realy make sence to me that there are two different fighter comparisons, where "downrated" and "uprated" planes get compared, while, accorsing to your post, the "downrated" planes should have been uprated at least 6 moth before this comparisons was made.
Greetings,
Knegel
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Originally posted by Knegel
Hi Widewing,
why the Temp with more weight climb better in your graph(blue/red line)??
What boost the Temp did use below 5k to archive the displayed climb down there??
I didnt know there was something called "fighter conference", if you have the Vaught docus, you should have known to which comparison i was refering to.
Anyway, the P38J and P51B was absolut common fighters till the end of war and absolut not outdated in oct.44. According to Bennys guess the usage of a higher presure as WEP was common in October 44 also for the P38J, since it seems that also the new P38L only got tested with a WEP of 60", while the P47D got its 2600HP i only can guess that at this time the 66" or higher boost dont got widely used in P38´s.
For now i only did read about the few recon P38L´s in Europe, using the higher boost, similar to the V1 intercepting planes.
When looking at the modified chart, the black line represents the third production Tempest Mk.V as tested by the AFDU. It shows both MIL power and Combat power climb at 9 lb boost. The Blue line represents the AH2 Tempest climbing at full load and 10.5 lb boost. Also plotted is the AH2 Tempest climbing at 25% fuel and 10.5 lb boost.
Now, here's where it gets interesting. If the AH2 Tempest is fitted with the Sabre IIA, it would be cleared for 10.5 lb boost only if using 150 octane fuel. If it is fitted with the Sabre IIB, it should pull 12.0 lb of boost. So, depending upon which engine was modeled, the AH2 Tempest is either too slow or too fast.
What we may have is an amalgam of the Sabre IIA and Sabre IIB, as the AH2 Tempest fits right in between the two.
Max Sea Level Speed for Tempest powered by:
Sabre IIA: 378 mph (9 lb boost)
Sabre IIB: 394 mph (12 lb boost)
AH2 Tempest: 388 mph (10.5 lb boost)
This makes sense to me, and I can see why HTC would model it that way.
As to the Vought data, I didn't recognize what you were referring to until you posted the actual pages.
By October of 1944, there were few, if any P-51Bs in combat service in the ETO or MTO. Most had been retired as War Weary by then. The same thing applies to the P-38J. Most, if not all had been replaced by the P-38L, and none were flying with the 8th AF by October. By then, all P-38 groups had transitioned to the P-51, with their remaining servicable P-38s being transferred to the 9th or 15th Air Forces.
My regards,
Widewing
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Hello Widewing:
The Tempest V with Sabre IIA was operated at +9 or +11 lbs/sq.in. 3700 rpm
The Tempest V with Sabre IIB was operated at +11 of +13 lbs/ sq.in. and 3850 rpm
Tempest V with Sabre IIB (http://www.wwiiaircraftperformance.org/tempest/tempest-v-ads-sabre-IIb.jpg)
Pierre Clostermann (Free French) wrote of the Tempest:
"Nothing was left undone to give the Tempest a maximum performance at medium and low altitudes. Special auxiliary tanks were designed even, with perspex connecting pipes, to fit under the wings. Quite extraordinary attention was paid to the rivetting, the joints and the surface polish. The result was a superb combat machine.
It had a thoroughbred look and, in spite of the big radiator which gave it an angry and wilful appearance, it was astonishingly slender. It was very heavy, all of seven tons. Thanks to its 2,400 h.p. engine it had a considerable margin of excess power and its acceleration was phenomenal. It was pretty tricky to fly, but its performance more than made up for it: at 3,000 feet, at economical cruising on one third power (950 h.p.) with two 45-gallon auxiliary tanks, 310 m.p.h. on the clock, i.e. a true air speed of 320 m.p.h.; at fast cruising speed, at half power (1,425 h.p.) without auxiliary tanks, 350 m.p.h. on the clock, i.e. a true air speed of nearly 400 m.p.h.; Maximum speed straight and level with + 13 boost and 3,850 revs.: 430 m.p.h. on the clock, i.e. a true airspeed of 440 m.p.h.
In emergencies you could over-boost it up to nearly 3,000 h.p. and 4,000 revs., and the speed went up to 460 m.p.h. In a dive the Tempest was the only aircraft to reach, without interfering with its handling qualities to any marked extent, subsonic speeds, i.e. 550-600 m.p.h."
Sable: nice :) I was going to post some thoughts here on the Mustang, but I think that deserves its own thread and I don't want to get off the main topic widewing is discussing.
Mike
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Hi Widewing,
so this is wrong??
"Most of the P-51B/Cs were assigned to the 8th and 9th Air Forces in England, with a lesser number with the 12th and 15th USAAF in Italy. The P-51B/C remained the prime Mustang variant in service from December 1943 until March of 1944, when the bubble-topped P-51D began to arrive. However, P-51B/C fighters remained predominant until the middle of 1944, and remained in combat until the end of the war in Europe even after the arrival of large numbers of P-51Ds. Even as late as the last month of the war, 1000 out of the 2500 Mustangs serving in the ETO were of the P-51B/C variety"
From this page, which i always thought to be a good one:
http://home.att.net/~jbaugher1/p51_8.html
(I know the late P51B/C´s got the newer engine anyway)
Whats about the climb of the Temp in low level, shouldnt be the Vmax at very low level also much better and in 3-5000ft??
Greetings,
Knegel
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Originally posted by Kev367th
Is it an order though, or a document of what they would like to do?
Even he states it is proposed changes.
Given that the LW was having to re-assign non essential fuel (including training and testing) to frontline units to come close to keeping sorties close to consistent from Jan 45 onwards, where does the extra C3 needed for 1.98ata come from, considering the 190s had to have it.
Or does it make more sense to leave things as they are, were the K-4's can use B4 or C3.
Should add also - did the ever get the plugs required for 1.98ata?
My main gripe - He said it took the RAF some 2 months from a clearence or order for a mod for it to start happening (look at the Spit I boost thread), yet quite happily asserts that in Germany 2 months from the end of the war some 76 K-4's were converted in those 2 months.
Funny how double standards crop up time and time again.
Agreed - I don't see any way to prove how many, or if 109 units got the 1.98ata boost.
Back on the original topic though - I tested the AH 109K at altitude vs some lookups I did on 109K performance, and they appear to be pretty close. The 109K at 24,600ft was doing 429 MIL / 445 WEP, which is about 5mph faster than my Janes has listed.
Weight of Ammo seems to make no difference to max speed - I managed to get the same 445mph loaded with ammo, and empty.
EagleDNY
$.02
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Originally posted by Knegel
Hi Widewing,
so this is wrong??
"Most of the P-51B/Cs were assigned to the 8th and 9th Air Forces in England, with a lesser number with the 12th and 15th USAAF in Italy. The P-51B/C remained the prime Mustang variant in service from December 1943 until March of 1944, when the bubble-topped P-51D began to arrive. However, P-51B/C fighters remained predominant until the middle of 1944, and remained in combat until the end of the war in Europe even after the arrival of large numbers of P-51Ds. Even as late as the last month of the war, 1000 out of the 2500 Mustangs serving in the ETO were of the P-51B/C variety"
From this page, which i always thought to be a good one:
http://home.att.net/~jbaugher1/p51_8.html
Yes, Baugher is incorrect. He is also contradicts himself by stating further in his article that, "Some 3740 P-51Bs and Cs were built. Some of the served with front-line units until the end of hostilities, but others were converted as two-seat trainers or squadron hacks."
Did you look at Baugher's sources? Generally pulp aviation books of dubious value. Baugher writes general histories based on what he has gleaned from standard pulp aviation titles, which are generally unreliable.
The number of Mustangs in the ETO was considerably less than 2,500. As of March 28 1945, 1,715 P-51s were in service with the 8th and 9th Air Forces (AAF Statistical Charts), as well as 1,974 P-47s and 249 P-38s. In the MTO we find 532 P-51s, 383 P-38s and 361 P-47s.
So, the grand total of P-51s service in both the ETO and MTO was 2,247 with about 5 weeks to the surrender. With P-51Ds and P-51Ks still arriving in great numbers, the number of P-51B/C fighters remaining would only shrink more by the war's end.
As of the end of March, 1944, the Luftwaffe was facing well over 5,000 American fighters as well as the fighter arm of the RAF and a considerable number of Soviet fighters. The total (not counting Free French or Italians) probably exceeds 10,000 fighters.
The best sources are Group and Squadron records. By October 1944, there were probably less than 100 P-51B/C aircraft still on combat duty with the 8th AF. Even the 9th AF was replacing its worn-out P-51B/C types with P-47s (virtually all P-51Ds were being allocated to the 8th and 15th Air Forces at that time). By D-Day, the majority of P-51s in many 8th Groups were P-51Ds. You see this in photos of this time period. Fast forward to January of 1945 and you don't see any P-51B/C fighters in photos.
Many of the last P-51B/Cs to roll off the line were sent to the CBI (early June of '44) to replace worn-out P-51A and P-40 types. All P-51B production ceased in early March of 1944, with the line being switched to the D model. Hundreds of P-51D-1 and P-51D-5 fighters were deactivated for being war weary, and assigned as hacks or used by the various Group's Clobber College combat training commands. Many were simply scrapped for spare parts.
One thing that kept many of the later P-51B/C fighters in service in the ETO and MTO was the delay of delivery of P-51Ks. The K model was fitted with an Aeroproducts prop and there were vibration issues associated with the propeller. This slowed delivery to a trickle. The first P-51Ks arrived in the ETO in September or 1944, replacing the older B and C models still soldiering on in combat squadrons.
I am not aware of a single P-51B/C still in combat service with the 8th AF when the war ended. There may have been some, but they do not show up on any of the Group end-of-war inventories that I have seen. There could not have been very many serving with the 9th and 15th Air Forces either.
My regards,
Widewing
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Hi Widewing,
thanks for this infos, thats very informative(like usual)!!
But anyway, although the P38J and P51B/C wasnt in production anymore, they was still in usage in probably not that smal numbers in oct.44.
What you call MTO was already rather ETO in oct.44, although it was the south front(german point of view) and the P51D in the other comparison also got tested with only 67", so the main argument stay valit anyway.
Afaik the P38L dont saw service in fighter units over europe, is this information also wrong??
Greetings,
Knegel
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Yes, it's wrong. The P-38L saw very much combat over Europe, and it did run at 70+ inches.
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Originally posted by Benny Moore
Yes, it's wrong. The P-38L saw very much combat over Europe, and it did run at 70+ inches.
But, only those P-38s serving in the 8th AF were running the high boost. The 9th AF and 15th AF were not issued 150 octane avgas (at least to my understanding). If they were running at higher than normal boost it was because the engines and regulators had been rigged for the full Allison rating of 1,725 hp courtesy of the Allison tech reps.
P-38 groups in the MTO were largely equipped with P-38L-1 and P-38L-5 aircraft. Well over 300 of them. P-38 Groups in the ETO (9th AF) were also flying P-38Ls. Again, well over 300 were in service there too.
My regards,
Widewing
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That sounds right. I was addressing Knegel's statements, "It seems that also the new P38L only got tested with a WEP of 60" and "P38L dont saw service in fighter units over europe."
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Hi Benny,
if you quote me, could you do that right please??
It was a question by me, not a statement!!
And the question remain, when and how often it did run on 70"!!
At least it dont seems to have been before oct.44, cause a fighter comparison only make sence when the common powersettings get used, not the older derated versions.
Afaik the P38´s had bad trouble in higher alt with the normal boost and fuel, maybe the 150 octan fuel made them only able to use 60" WEP without to fear dead engines up there?
Hi Widewing,
its realy interesting and scary to see how much datas in books vary from obvious historical base sources.
So the P38L took place in Europe as fighter not only as recon plane! Good to know, thanks!
Greetings,
Knegel
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Originally posted by Knegel
So the P38L took place in Europe as fighter not only as recon plane!
Captain Hallberg (http://www.geocities.com/Pentagon/Quarters/6940/hallberg.html)
Best Regards
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Originally posted by Knegel
Hi Benny,
if you quote me, could you do that right please??
It was a question by me, not a statement!!
And the question remain, when and how often it did run on 70"!!
At least it dont seems to have been before oct.44, cause a fighter comparison only make sence when the common powersettings get used, not the older derated versions.
Afaik the P38´s had bad trouble in higher alt with the normal boost and fuel, maybe the 150 octan fuel made them only able to use 60" WEP without to fear dead engines up there?
Hi Widewing,
its realy interesting and scary to see how much datas in books vary from obvious historical base sources.
So the P38L took place in Europe as fighter not only as recon plane! Good to know, thanks!
Greetings,
Knegel
Knegel
Well as far as I know the earlier 38s had problems at high alt due to over cooling. Start an older carbed auto with a stuck open choke. Then floor it while it is still cold, you will in effect shut off the engine. That was happening to the early 38s.
The latter models (if I remember right), fixed this or found a work around.
Bronk
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Early P-38s also had trouble with regulating the turbocharger, as did the B-17 and B-24s.
For some reason they also had troubles caused by using Brit avgas.
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Well how about this for the list:
1- 38 flaps auto-retracting
2- 38 guns able to fire 1 .50 cal gun at a time if you 'tap' the trigger (all 4 should fire at the same time)
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Originally posted by MiloMorai
Early P-38s also had trouble with regulating the turbocharger, as did the B-17 and B-24s.
Somehow 8th Air Force was able to manage 1,000 aircraft missions of 17's and 24's that were escorted by a couple of groups of P-38's regardless. I know this thread turned into a P-38 boost thread, but I honestly don't see how any of this bears on the game, since the dang turbo works every single time you turn the engine on, regardless of altitude. It could be fathomable that if HTC raised the boost levels on the U.S. rides, the Spits, and even the 109K4 to the levels listed above, they'd have to perk the whole damn lot of them. I'm content with my currently modelled Jug manifold pressure the way it is, and I've been spanked by enough P-38's and K4's in their current configurations to know that they are plenty effective as they are currently represented. If they kicked the MP up to 70 inches, and as a result had to put a light perk on the plane, it would kill it for me. Just leave it be and don't demand uber performance in your favorite ride from what I would consider, IMHO a planeset that is currently balanced, relatively speaking, to what it was in real life. It may not be 100% accurate, but its probably close to a 90% solution. And, given the plethora of variables, contradictory historical documentation, and all the residual historic sludge that exists on the Web, I'd say 90% may be as close as they can get, with respect to the different aircraft. Bugs are one thing, but arguing over 10" of manifold pressure that was only available to one Air Force out of 15 that existed in WWII I believe is pointless. If they want to add it to CT in an 8th AF setting, that's their perogative, and will certainly be their decision. Meanwhile, in the rest of the war, this conversation has no bearing. If the flight model could be tweaked to better represent stall characteristics, torque, p-factor, and all those other things we initially started talking about, that's another matter.
My last post on this subject. Widewing, I look forward to your next thread regarding this--at least the first dozen posts or so.
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Yep Stoney, absolutly right!!! :aok
At the end the relations matter not the static datas, like Vmax etc and as you say, the relations in AH looks rather good to me and i love to fly the 190A8 and P47´s!!
Greetings,
Knegel
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Originally posted by mw
Pierre Clostermann (Free French) wrote of the Tempest:
It had a thoroughbred look and, in spite of the big radiator which gave it an angry and wilful appearance, it was astonishingly slender. It was very heavy, all of seven tons. Thanks to its 2,400 h.p. engine it had a considerable margin of excess power and its acceleration was phenomenal.
I routinely find myself questioning Clostermann's statements. Like Brown, I think he has a tendency towards overstating. However, in this case I think he's not far off.
First, let me use an image from one of your documents. It is not data in the sense that it defines acceleration. It does, however, establish a general ranking in terms of relativity. So, is this accurate? We will see.
(http://www.wwiiaircraftperformance.org/wade-accel.jpg)
We can calculate a reasonably close rate of acceleration if we can determine several unknowns. These are propeller efficency and drag. We can use a constant for the the prop, but may have to estimate drag.
We can calculate the approximate thrust available at a given speed. To do this, we must estimate the efficiency of the propeller. If we begin at 150 mph, a typical WWII prop will demonstrate approximately 70% efficiency. If this is applied to all examples, it becomes a fair, if not perfectly accurate method. Note that 2,400 hp in the Tempest is at 11 lb boost.
Thus, for the Tempest:
375 x .7 x 2,400 / 150 = 4,200 lb of thrust.
For the Spitfire Mk.XIV:
375 x .7 x 2050 / 150 = 3,588 lb of thrust.
Now that we know the available thrust, we can calculate acceleration in feet per second, per second. Of course, we need to know what the total drag is. This can also be calculated or obtained from a reliable source. In this case, I'm going to use what I believe are close estimates.
Total drag for the Tempest: 1,350 lb
Total drag for the Spit XIV: 990 lb
Thus, thrust - drag / mass (in slugs) = initial acceleration in feet per second, per second.
Tempest: 4200 - 1350 / (11480/32.2) = 7.99 feet per second, per second.
Spit XIV: 3588 - 1090 / (8500/32.2) = 9.46 feet per second, per second.
Let's toss in the P-51D for comparison. I am calculating based upon an empty rear aux fuel tank (always burned off first on climb-out)
P-51D: 3010 - 845 / (9611/32.2) = 7.25 feet per second, per second.
Results, initial acceleration rate in g:
Spitfire Mk.XIV: 0.294 g
Tempest Mk.V: 0.248 g
P-51D: 0.225 g
Initial acceleration in the game, full load except for P-51D with 75% fuel. Time to accelerate from 150 mph to 200 mph at 100 feet ASL.
Spitfire Mk.XIV: 8.12 seconds (18 lb boost)
Tempest Mk.V: 8.16 seconds (10.5 lb boost)
P-51D: 10.81 seconds (67 in/hg boost)
The relationship between the Spitfire XIV and P-51D is reasonably close to the calculated acceleration (30% calculated vs 33% actual testing)
However, the difference between the Tempest and P-51D is much different (10% calculated vs 32% actual testing). In short, the AH2 Tempest appears to accelerate much faster than it should for the given boost and horsepower. Even if I reduce the Tempest's drag by 200 lb, it still should not accelerate as fast as it does in the game.
By the way, this tends to show that the acceleration chart above is flawed.
My regards,
Widewing
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Originally posted by Widewing
By the way, this tends to show that the acceleration chart above is flawed.
My regards,
Widewing
Could it be that the chart is giving a representation of relative performance at typical combat altitude or would that even affect it? By that, I mean would the comparison between a P-47 and Tempest at 25,000 feet be less or more closely represented by the chart than the same relation between sea-level acceleration? I'm not sure about the Sabre in the Tempest, but at the P-47's critical altitude, some of the engines in the planes on this chart would be wheezing, relatively speaking, right?
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Originally posted by Stoney74
Could it be that the chart is giving a representation of relative performance at typical combat altitude or would that even affect it? By that, I mean would the comparison between a P-47 and Tempest at 25,000 feet be less or more closely represented by the chart than the same relation between sea-level acceleration? I'm not sure about the Sabre in the Tempest, but at the P-47's critical altitude, some of the engines in the planes on this chart would be wheezing, relatively speaking, right?
Though the document does not specify what altitudes were used, it does at least hint that the chart represents sea level acceleration.
Here's a quote from the related text:
"The ability to accelerate quickly is of paramount importance to fighters and the interceptor class has an obvious advantage in this respect. For comparative purposes it is impracticable to take into account maximum speed as acceleration is only operationally useful at the slower speeds when an interception suddenly has to be made from slow cruising.
For instance, the Tempest V, which is faster than the Spitfire XIV, takes less time to reach any given speed, but the Spitfire has the best acceleration, followed by the Mustang III, Tempest V, Thunderbolt and Meteor III. The unhappy position of the Meteor is accounted for by the natural sluggishness of early jets at the lower speeds. Here again, the power to weight ratio coupled with clean lines in design has considerable effect."
In one regard, there seems to be a contradiction. "For instance, the Tempest V, which is faster than the Spitfire XIV, takes less time to reach any given speed, but the Spitfire has the best acceleration,"
If the Spit XIV accelerates faster, it will reach a given speed faster. However, acceleration rates vary as your speed increases. In the game, from 150 mph to 200 mph, the Spitfire XIV accelerates faster and reaches 200 mph sooner. However, from 200 mph to 250 mph, the Tempest accelerates faster and thus, reaches 250 mph sooner. Perhaps, this is what the author meant.
My regards,
Widewing