Improve the P-47

[gripen]

Originally posted by Captain Virgil Hilts

The last P-38 raced at Reno that I remember is Lefty Gardner's "White Lightning" (since sold to "Red Bull" drink corporation), and it is VERY stock. In fact, it uses, or used, stock surplus engines right out of the crate. The last time I saw it the turbochargers were not mounted, just the shields and covers were there. It also is set up as an early type recon plane with the low drag cowls. From what I understand, the "modification to "White Lightning" is only that it was converted from a late model P-38 recon plane to an early model. That's what I was told and saw evidence of, it may have changed.

Looking the pictures from Reno in the Gardner's web site; the engines are handed and there is no turbos installed. If the engines were stock with original 8,1:1 SC gear ratio, it's unlikely it could do much more than 60" even if running at 3200rpm or bit more at 5k. So the speeds reached in the race were probably much less than 500mph true.

gripen

[Charge]

"The British Aircraft Purchasing Commission tested the P-38 with turbo-superchargers and found that the turbines need 10 s to spool up from idle to full power. That meant that on take-off, you'd have to hold the P-38 on brakes until the engines were running at full power, or you'd suffer from a rather long take-off run (because you'd make most of it at less than full power)."

Interesting. I'd say that the spooling time is because of the supercharger size, not because of the piping or intercoolers. The turbo probably needs to be quite big to be able to feed the engine sufficiently up high, so the exhaust thrust in ground level only slowly accelerates the turbine. That means that if you cut the power from full throttle the waste gate opens wide open and the boost is readily available for some time since the turbine does not slow down rapidly.

At least thats how I understand it....

-C+

[Col. Flashman]

Originally posted by Widewing
Performance is modeled from actual test data. Pilot reports are largely useless for modeling aircraft. What data are you using?

My regards,

Widewing

Thank'ee for responding.

I travelled to Air Shows quite a lot between the ages of 8 & 35, where I met & spoke w/ Test, Pursuit Ship & Fighter Pilots about the A/C they tested & actually flew in Combat during WW II. I’ve also an informative collection of Aviation material covering this era of flight & have had access to Original Spec Sheets/Books/Lit on the A/C I was rather interested in.

I managed to get a ride by paying for 1/2 the fuel & got a tick of unofficial stick time in the Piggyback version of the P-40, as well as several other different Piggeyback Fighters in Private Owner/Operator hands. We were able to achieve well over 340mph IAS in the P-40 between Sea Level & 15,000’ w/ full fuel on board, there were exact weight fake 50s mounted in the wings & according to the Owner/Pilot, we were @ least 3/4 Combat Loaded during this flight & he really wrung the Olde Girl out for me, I had a slight green tinge when I climbed out afterwords.

So what you are stating here is that what the Combat Pilots actual experiences under Varying Weather & Combat Conditions in regards to the Performance & Handling characteristics of the A/C they are flying w/ full, 3/4,1/2,1/4, Combat Loads, finding that the Indicated Air Speed, Climb Rate, Power Dive Ability, Turn Rate, etc., was better or worse or the same when measured against the Test Data stated in the Spec Sheets & from the Test Pilots sent by  the Company that were on hand for the training flights, is of no consequence & useless to you.  

I’ve read here that the P-40 cannot Power Dive to save itself, so it can speed away @ tree-top-level from an opponent, to enable the Pilot can Climb back to Alt. to start all over again.
Which happens to be the one of the Main Combat Tactics taught to P-40 Pilots to keep from being shot down so that they can re-engage or arrive back to their Aerodrome safely. P-40 Pilots have reported 600mph IAS during Power Dives, which scared the Devil out of them not believing they'd be able to pull out of it & were able to maintain speeds over 400mph IAS @ tree-top-level before the climb back for Alt. FEAF, RAAF, RNZAF, USAAC & the AVG Pilots made these reports, have written books, given interviews & they are out there for public consumption.

I’ve read here that the Max IAS in level flight from Sea Level to 10,000’ is somewhere in the 290mph range, which is well below the 325mph to 350mph, all in IAS mind you, reported by Combat Pilots & they were able to achieve that between those Alt’s. It is my understanding that Aspirated, Fuel Injected, Turbo, Super & Turbo-Supercharged Recip A/C Perform better @ Sea Level to 10,000’ because Air/Fuel Ratio is @ its best because the air hasn’t thinned out enough yet to effect Performance.

Your flight models, for me, on 3/4's of the A/C I've flown, won’t go over 200mph IAS in the Practice Area of the game @ any Alt. I’ve lots of sim & real flight time, so this is rather puzzling to me. My “Wingman Force 3D” is set up properly also.

One of the main complaints from the FEAF B Pilots that had to quickly transition to the E model under Combat Conditions, was the difference in CG & Weight, making handling different, making for longer T/O’s runs & not being as responsive in the air "to them" compared to the B model & just the opposite for the E Pilots to the B model, in their P-o-V's. I only point this out as I read in the Forum that you use the same flight model for both B & E ‘s.

Cheers

[Knegel]

Hi,

noone say the P40 cant reach 350mph, but it didnt reach such speeds just in level flight and it for sure couldnt maintain 400mph, at least not for long!!

In a smooth dive the planes fast overcome their Vmax(level flight). From 13000ft and a initial speed of 200mph IAS i just reached 550mph in a dive and the P40 still was good manouverable.
In AH, vs the Zero, the P40 can disengage very well by diving away.

btw 600mph are already mach 0,78 at 20°C, i guess from 18000ft downward thats good possible in AH, but i was to lazy to climb that high.

The testdatas are mostly made with combatworthy planes, actually they was made to give datas to the pilots, would be bad to use special planes and to feed the own pilots with wrong datas, eh??

If you cant get above 200mph, you should stop to climb!

Greetings,

[Widewing]

Originally posted by Col. Flashman
Thank'ee for responding.

I travelled to Air Shows quite a lot between the ages of 8 & 35, where I met & spoke w/ Test, Pursuit Ship & Fighter Pilots about the A/C they tested & actually flew in Combat during WW II. I’ve also an informative collection of Aviation material covering this era of flight & have had access to Original Spec Sheets/Books/Lit on the A/C I was rather interested in.

I count several test pilots from Curtiss, Grumman, Republic and North American as friends. Some are now dead. I am also friends with some well known WWII fighter pilots (living and recently deceased) and keep a correspondence running with several others less well known. I also have a decent collection of AAF, USN and factory test data on hand, as well as an extensive personal library and over 15,000 photos digitally preserved from original prints or prints from original negatives.

I managed to get a ride by paying for 1/2 the fuel & got a tick of unofficial stick time in the Piggyback version of the P-40, as well as several other different Piggeyback Fighters in Private Owner/Operator hands. We were able to achieve well over 340mph IAS in the P-40 between Sea Level & 15,000’ w/ full fuel on board, there were exact weight fake 50s mounted in the wings & according to the Owner/Pilot, we were @ least 3/4 Combat Loaded during this flight & he really wrung the Olde Girl out for me, I had a slight green tinge when I climbed out afterwords.

Many of us playing Aces High have flying experience, both military and civilian.

So what you are stating here is that what the Combat Pilots actual experiences under Varying Weather & Combat Conditions in regards to the Performance & Handling characteristics of the A/C they are flying w/ full, 3/4,1/2,1/4, Combat Loads, finding that the Indicated Air Speed, Climb Rate, Power Dive Ability, Turn Rate, etc., was better or worse or the same when measured against the Test Data stated in the Spec Sheets & from the Test Pilots sent by  the Company that were on hand for the training flights, is of no consequence & useless to you.  

What I am stating is that HTC will only use actual test data to model aircraft. They cannot and will not use anecdotal evidence, IE: combat pilot reports. These are unreliable for many reasons. There's plenty of test data taken at Eglin, Anacostia and Langley, etc, plus factory test data to establish what aircraft performance was when the aircraft were in service.

I’ve read here that the P-40 cannot Power Dive to save itself, so it can speed away @ tree-top-level from an opponent, to enable the Pilot can Climb back to Alt. to start all over again.

The P-40s as modeled in AH2 dive very well. Your perception is incorrect.

Which happens to be the one of the Main Combat Tactics taught to P-40 Pilots to keep from being shot down so that they can re-engage or arrive back to their Aerodrome safely. P-40 Pilots have reported 600mph IAS during Power Dives, which scared the Devil out of them not believing they'd be able to pull out of it & were able to maintain speeds over 400mph IAS @ tree-top-level before the climb back for Alt. FEAF, RAAF, RNZAF, USAAC & the AVG Pilots made these reports, have written books, given interviews & they are out there for public consumption.

I believe that you mean 600 mph TAS, not IAS. 600 mph IAS at 8,000 feet translates into 696 mph true airspeed (nearly Mach 0.93)... Much faster than any WWII fighter could attain.

I have dive tested the AH2 P-40B and you can reach at least 605 mph TAS in a terminal velocity dive. Dive acceleration is what I expected, better than the A6M2, but inferior to the F6F or F4U.

I’ve read here that the Max IAS in level flight from Sea Level to 10,000’ is somewhere in the 290mph range, which is well below the 325mph to 350mph, all in IAS mind you, reported by Combat Pilots & they were able to achieve that between those Alt’s. It is my understanding that Aspirated, Fuel Injected, Turbo, Super & Turbo-Supercharged Recip A/C Perform better @ Sea Level to 10,000’ because Air/Fuel Ratio is @ its best because the air hasn’t thinned out enough yet to effect Performance.

Here's how the P-40E performs in AH2....

Your flight models, for me, on 3/4's of the A/C I've flown, won’t go over 200mph IAS in the Practice Area of the game @ any Alt. I’ve lots of sim & real flight time, so this is rather puzzling to me. My “Wingman Force 3D” is set up properly also.

Obviously you have issue with your throttle...  I have no problem getting rated speed out of any fighter in the game. I've tested every fighter in the game at sea level, 10k, 20k, 25k and 30k. All perform to the posted charts, but low fuel fighters are always a bit faster (2-5 mph) as one would expect.

One of the main complaints from the FEAF B Pilots that had to quickly transition to the E model under Combat Conditions, was the difference in CG & Weight, making handling different, making for longer T/O’s runs & not being as responsive in the air "to them" compared to the B model & just the opposite for the E Pilots to the B model, in their P-o-V's. I only point this out as I read in the Forum that you use the same flight model for both B & E ‘s.

There are some issues with the P-40s, IMHO. First, our P-40B offers performance identical to the P-40C, with its added weight and drag (measured in-game at 338 mph TAS @ 16,000 feet, 25% fuel, zero fuel burn). That should be addressed, or at least the designation should be changed to P-40C and the drop tank option be added. Second, our P-40E has a War Emergency Power rating. No P-40E was so equipped (V-1710-39 did not have a WEP rating). So, it performs more like the P-40K-1, with the V-1710-73 engine. Also, both P-40s are able to lower full flaps at 171 mph IAS, when the pilot's manual states that 140 mph IAS was the max permitted for full flaps. Aside from these minor issues, I can find no significant fault in the flight behavior of either P-40.

Here's the chart for the AH2 P-40B... It is exactly the same for that which I have for the P-40C, but the P-40C is 400 lb heavier and has the added drag of the fuel tank shackles.



In general, your perceptions of aircraft performance in Aces High is way off the mark. Swing by the Training Arena and we'll help you get your throttle properly calibrated. You'll see a huge improvement in aircraft performance.

My regards,

Widewing

[Angus]

Flashman: (Harry flashman ?)
Of diving:
"Which happens to be the one of the Main Combat Tactics taught to P-40 Pilots to keep from being shot down so that they can re-engage or arrive back to their Aerodrome safely."

This worked against opponents from Japan mostly, - but not when you'd meet a 109 or a 190 for instance.....P40's were used quite a bit in the med where the opponents were mostly much faster than in the pacific.

[Debonair]

i think i remember reading that early on in North Africa, P-40s could dive away from the 109s.
not the 109F, though...

[Angus]

Neville Duke commented on flying the P40 against the 109's where the 109's often gave them a bad day, - he got shot down a couple of times I belive.
Now I'm curious enough to start reading

[Squire]

The wartime P-40E could attain @360 mph TAS tops with a good engine at optimum alt, flying at full power "flat out" in level flight. I give it the extra 5-10mph to give it the benefit of a very well tuned engine, perhaps exceeding its rated manifold settings, and using 100/130 fuel. You would not have likely got that out of an operational bird in the Pacific, Africa, or Burma.

There isnt an ex P-40E pilot, living or dead, of any nation, that ever claimed it could attain anything faster than that, unless it was diving.

The fastest wartime P-40 (in squadron service) was the P-40N of 1944, which could do @380 mph TAS tops.

[Captain Virgil Hilts]

Nice hijack. This WAS a P-47 thread. Or at least MOST of the 1st 4 pages were.

[Squire]

The thread is from September 21st, and is over 200 replies, I hardly think its a "hijack". They all go OT at some point, and I think the conversations have been related in a generalized way, which is keeping with the spirit of the forum.

When we start yelling at each other over the War of 1812, and what the French did or didnt do at Waterloo, then thats a hijack.

[scottydawg]

Originally posted by Squire
When we start yelling at each other over the War of 1812, and what the French did or didnt do at Waterloo, then thats a hijack.

Oooooh, so tempting...

[Debonair]

Originally posted by Angus
Neville Duke commented on flying the P40 against the 109's where the 109's often gave them a bad day, - he got shot down a couple of times I belive.
Now I'm curious enough to start reading

squawking 7500 & i have Neville Duke's book, read it a couple years ago.  Great read.


part of it was a P-38 thread too, but you can't really talk about improving a plane without comparing it to other planes & iirc was a part about getting your PP/AMEL/IA

[Col. Flashman]

Originally posted by Angus
Flashman: (Harry flashman ?)
Of diving:
"Which happens to be the one of the Main Combat Tactics taught to P-40 Pilots to keep from being shot down so that they can re-engage or arrive back to their Aerodrome safely."

This worked against opponents from Japan mostly, - but not when you'd meet a 109 or a 190 for instance.....P40's were used quite a bit in the med where the opponents were mostly much faster than in the pacific.

Yes, one in the same.
In the Med & N.A., the R.A.F. were still using the Lufbery Circle as their main Defensive Tactic against Bf-109's, so it's no wonder that they weren't having much success w/ the P-40, as they weren't taking advantages of her strengths & letting the 109's exploit her weaknesses.

[Knegel]

Hi,

what was the strengths of rhe P40E over the 109F4??

Greetings,