Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: AGJV44_Rot 1 on February 26, 2003, 05:23:53 PM
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Finally found the problem with the Dora. Dora’s climb rate and speeds are 2 different sets. Given the current top speed and climb for the Dora they match up with a different set of power settings. With the current top speed we have the Dora is using B4 fuel with MW50 a deck speed of 377-78 and a top speed at alt of 429-30 which looks to be the case according to the charts by HTC. This is chart number 4 in column 2. Now according to the climb chart which HTC provides the Dora would have to have been using this setting 1-Sonder-Notleistung / Special Emergency to achieve it. This is chart number 1 in column 1. According to this chart the setting HTC is using for climb is Special Emergency, for performance HTC is using Sonder - Notleistung (B4) mit Laderdruckerhoehung mit MW50 u. 1.8ata. 2 Different settings for performance. Why is this? If we were to have the same power setting for climb then why can’t it have the same power setting for performance? This may not seem like much but according to these settings the speeds would be drastically different giving a top speed of 438 mph at 18000 feet and a deck speed of 382, according to the power setting. I have not included all of the speeds but you can find them here at this location http://jagdhund.homestead.com/files/Dora.htm These numbers are taken from a chart produced by Focke-Wulf Flugzeugbau G.M.B.H dated March 11, 1945
If this means lowering the env value I am all for it to make sure it is correct.
Steigleistungen
1-Sonder-Notleistung / Special Emergency
2-Start-und-Notleistung / Takeoff and Emergency
3-Steig und Kampfleistung / Climb and combat
4.Hoechstzul. Dauerleistung / Power for best endurance
Settings for climb use column 1
Horizontalgeschwindigkeiten
1 - Start - u Notleistung (B4) -- Take off/Emergency
2 - Sonder - Notleistung (C3) /Special Emergency
3 - Sonder - Notleistung mit A Lader als Bodenmotor (Special Emergency with Compressor as Base-Engine)
4 - Sonder - Notleistung (B4) mit Laderdruckerhoehung mit MW50 u. 1.8ata.
Settings for true air speed use column 2
Steigleistungen
Column 1
Altitude Power Setting & feet per minute
ft 1 2 3 4
0 4,331 3,563 3,071 2,343
328 4,328 3,558 3,069 2,337
656 4,325 3,554 3,066 2,332
984 4,322 3,549 3,064 2,326
1,312 4,319 3,545 3,062 2,321
1,640 4,316 3,540 3,059 2,315
1,969 4,313 3,536 3,057 2,310
2,297 4,309 3,531 3,054 2,304
2,625 4,306 3,527 3,052 2,299
2,953 4,303 3,522 3,050 2,293
3,281 4,300 3,518 3,047 2,288
3,609 4,297 3,513 3,045 2,282
3,937 4,294 3,509 3,043 2,277
4,265 4,291 3,504 3,040 2,271
4,593 4,236 3,499 3,038 2,266
4,921 4,181 3,495 3,036 2,260
5,249 4,126 3,490 3,033 2,255
5,577 4,071 3,486 3,031 2,249
5,906 4,016 3,481 3,029 2,244
Horizontalgeschwindigkeiten
Column 2
Altitude Power Setting & true Air Speed
ft 1 2 3 4
0 353 382 398 377
328 354 383 399 378
656 355 384 400 379
984 356 385 401 380
1,312 358 387 402 381
1,640 359 388 403 382
1,969 360 389 404 384
2,297 361 390 405 385
2,625 362 391 406 386
2,953 364 392 407 387
3,281 365 393 408 388
3,609 366 394 409 390
3,937 367 395 410 391
4,265 368 396 411 392
4,593 370 398 412 393
4,921 371 399 413 394
5,249 372 400 414 396
5,577 373 401 415 397
5,906 374 402 416 398
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Nice work...although it will be even harder to catch those run90s if this turns out to be relevant!
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I need to upload the doc file I have it on I just posted it in here because it was easier to do and I was out of time. It clearly shows from HTC's data that the two power outputs are indeed different. My question is this how can we have the great climb but get jipped with the same outpout settings for top speed at alt??? I really would like Pyro to answer this as I think this is more then enough proof for a change for the Dora. Others have posted this data before but I have never seen anyone compare the two datas from this angle.
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Hi AGV,
A comment on curve 3: The translation of
"Notleistung mit A Lader als Bodenmotor"
as
"Special Emergency with Compressor as Base-Engine"
is not quite adequate.
It should be:
"Emergency power with A-type supercharger as dedicated low-altitude engine."
"A-type" refers to the Jumo 213A supercharger - there was also the E-type supercharger which made the Jumo 213E a dedicated high-altitude engine.
The power output for curve 4 is 1900 HP, for curve 3 it's the 2100 HP listed by most sources as maximum power for the D-9.
The 4331 fpm (22 m/s) climb matches the 2100 HP well, the 1900 HP climb should be well below - 300 HP make a difference, of course :-)
Regards,
Henning (HoHun)
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It's porked.. fix it you bastard! :D
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fix it and perk it along with the lame7 :D
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Pyro??? Any response or help on this matter would be appreciated.
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Originally posted by AGJV44_Rot 1
Pyro??? Any response or help on this matter would be appreciated.
i heard pyro has a soft spot for people who hold their breath until he answers them.
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Originally posted by AGJV44_Rot 1
My question is this how can we have the great climb but get jipped with the same outpout settings for top speed at alt??? I really would like Pyro to answer this as I think this is more then enough proof for a change for the Dora.
That's surely gonna get HTC to answer you. No offense, but the way you just phrased this has ensured that Pyro and company will probably never respond to you.
-- Todd/Leviathn
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Sorry Lev, but how do you know?
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Originally posted by RightF00T
Sorry Lev, but how do you know?
Apparently you haven't read the incredibly long thread where the Luftwhining came to a head, and HiTech basically stated that the manner in which Luftwaffe fans frame their complaints really matters. It's right here (http://www.hitechcreations.com/forums/showthread.php?s=&threadid=74315), I believe.
Then reread how AGJV44 describes 190D9 pilots as "jipped," and you'll understand.
-- Todd/Leviathn
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As i have those charts as harcopies i just want to throw in a few words.
The Speedchart is from 11. March 1945
The Climbchart is from 23. March 1945
And in the Climbchart there is no indication on which of the multiple Sondernotleistungs-Settings the chart is based.
It is very likely the C3 fuel Special Emergency, but might as well be the B4fuel+MW50+Ladedrucksteigerungsrüstsatz power setting.
And the actual difference between those two (in Speedchart they are #2 & #4) is somewhere around 30-50PS, not more.
The maximum speed differences between both are only 6 mph.
And best speeds are attained at slightly different altittudes, which might have to do with a different power development between B4 and C3 fuel over altittude.
The actual power output is the following:
#2 special emergency (C3) ~ 2130PS @SL
#4 special emergency (B4+MW50+1,8ata) 2100PS @SL
#3 special emergency power with A-type supercharger 2240PS or more@SL (this could not be cleared yet)
I know i have gone through this with HoHun more than one time, but there is no 1900PS power setting using MW50.
1900PS are achieved through a simple boost pressure increase, without any MW50 or fuel injection.
This is also verified by an british report, regarding to a FW190D9 that crashlanded during OP Bodenplatte (Jan 1945).
This maschine had 2 Emergency Settings.
#1 being Ladedrucksteigerung (Boost pressure increase) giving 1900PS
#2 being Ladedrucksteigerung + MW50 injection, giving 2100PS.
@AG: The difference in climbrate between those two power settings would not be great, and as the climbchart nowhere mentions which Sondernotleistungs-setting was actually meant, it might well be right that it fits to the MW50 setting.
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Naudet, you're basically saying that we have in AH a 1900PS Dora without any of the standard German WEP systems like MW50? Is this right?
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No i am basiciclly saying we have a 2100PS Dora in AH.
Might have confused u with all the #x and #y.
Just look again at this:
The actual power output is the following:
#2 special emergency (C3) ~ 2130PS @SL
#4 special emergency (B4+MW50+1,8ata) 2100PS @SL
#3 special emergency power with A-type supercharger 2240PS or more@SL (this could not be cleared yet)
Those are the #-designation for the curves in the Original Speedchart.
AGs assumption was now (as the Climbchart only read Sondernotleistung, but no additional explanation), after looking at AHs charts that AH's D9 uses setting #4 for speed and setting number #2 for climb.
This would indeed be somewhat contrary, as those two settings don't even use the same fuel.
My opinion is, that 1st, it is not clear to which Sondernotleistung-Powersetting the climbchart reffers. And 2nd, that it makes not much of a difference as the power output of those two settings only differs by ~30PS.
So AH has a D9 producing something between 2100-2130PS.
Hope i got it clear now.
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The 190D-9 in AH should have MW50. You will note that the AUX fuel tank is unavailable; you can use this tank on the A-8.
J_A_B
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And just for those that don't know, if I remember correctly myself, when Naudet brought this issue up a long time ago Pyro did step in and make a comment in the original thread.
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Hi Naudet,
I'm afraid that you are completely wrong in your assumptions about the Fw 190D-9.
The charts that were available from BBury's web site explicetly indicated:
Schwebeleistung im Schnellflug - 1925 PS - 611 km/h
Equilibrium power in fast flight - 1925 HP - 380 mph
(The scaling of power for relative air density proves this is sea level power.)
That means 1925 HP will get you curve 4 or 2. Curve 3 indicates 640 km/h at sea level, a speed increase of 4.7% requiring a power increase of 15% or from 1925 HP to 2200 HP.
I estimate that 50 HP of these are provided by increased exhaust thrust, leaving 2150 shaft HP. The Jumo 213A engine chart shows a wet WEP of 2140 shaft HP - perfect match.
So, a 2100 HP Dora will yield curve 3.
If you don't get (edit:) 398 mph on the deck, your Dora has less than 2100 HP.
Regards,
Henning (HoHun)
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Originally posted by Dead Man Flying
Apparently you haven't read the incredibly long thread where the Luftwhining came to a head, and HiTech basically stated that the manner in which Luftwaffe fans frame their complaints really matters. It's right here (http://www.hitechcreations.com/forums/showthread.php?s=&threadid=74315), I believe.
Then reread how AGJV44 describes 190D9 pilots as "jipped," and you'll understand.
-- Todd/Leviathn
I have to say lev that if you consider this post a question thats asked in a poor manner youre being incredibly harsh. the word 'jipped' in my country has no meaning at all. I took 'jipped' in 'My question is this how can we have the great climb but get jipped with the same outpout settings for top speed at alt??? as 'stuck with'. Im not having a go i just think maybe youre being a little oversensitive here.personally I cant read german and im no mathematitian so i dont have an opinion here but if AGJ has done his sums and or is correct about what hes found I fail to see where he has been rude or impolite or has in any way implied anything 'against' HTC unless 'jipped' means something really bad!.
Its merely a question with perhaps a little bit of impatience.Pyro i bet has read it and before he answers he'll look it over.We cant expect him to comment without checking it out first and I'd guess he's fairly busy on AH2 atm.I think given time he will answer and i hope he hasnt taken offense here. If he has I for one cannot understand why, give AGJ a break here lev, hes worked hard to find this stuff and he has the same right as anyone to question stuff if he sees discrepencies.
btw what does 'jipped' mean? :D
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But here in the States "jipped" or "gyped" is used when someone is being dishonest, i.e. a ripoff. Not exactly a complimentary term, by any means.
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isnt that 'duped' ? 'jipped' has no meaning in any dictionary i can find. nearest word is 'japped' which means 'mockingly'.
ahh well i guess only AGJ could say what he implied. Im only sorry another thread has returned to the age old debates.I think ill steer clear of this topic if a single word can cause so much grief .
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AGJV44's posts are littered with sublteties that shout "luftwhine".
Originally posted by AGJV44_Rot 1
Finally found the problem with the Dora.
What problem? Is there some well known problem with the D9 FM I'm not aware of? Since you dont specify what "the problem" is people will assume its that the Dora doesnt sweep the enemy from the skies effortlessly like you think it should.
Dora’s climb rate and speeds are 2 different sets. Given the current top speed and climb for the Dora they match up with a different set of power settings...If we were to have the same power setting for climb then why can’t it have the same power setting for performance?
You havent seen what data Pyro uses, yet you proclaim to know what he's done wrong.
My question is this how can we have the great climb but get jipped with the same outpout settings for top speed at alt???
jip - to deny something unfairly, eg. short-change. Also, it sounds like "we" means "LW flyers", as if you're different from the rest of the community. Everyone benefits from accurate FMs regardless of their favorite plane. There's no reason for squad or country affiliations to be involved at all.
[/B]
The whole thing read like a setup. So Pyro could come in here and say "we have data that confirms the current model, but I can't show it to you or say where we got it." And the response would be "See, I proved the D9 FM is wrong but Pyro won't change it! He obviously hates LW!"
Notice how there is no problem with the data, just the way its presented.
All you had to say was something like "Hey Pyro found this data and when I compare it to AH charts, the climb matches power setting x and the speed matches power setting y. Does the AH D9 use different power settings for climb and level flight?"
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Everyone shut up. This is turninig into another luftwhine witchunt where people jump all over each other. He said what he said, and Pyro can do whatever he wants - he doesnt need people attaking the poster.
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To answer all before this turns into another LW whine thread, I am asking for a look at the data. I am sorry If I used the word Jipped, meaning (read my above text's) having 2 seperate power settings. This is not a whine but a serious inquiry into what I have looked into. This whole labeling crap has gotten way out of control. If I were to come in here tomrrow with P-51 data saying it was faster on the deck who would be on the bandwagon? All I am asking is for checking of the data. If I am wrong so be it, no more complaints. I am really tired of this LW whining crap.
I know guys like F4U1D put a lot of time into their research and how many jump on his Arse for submitting data??? I envy him for researching a plane that he has so much passion for. I apologize for using the word "Jipped" might not have been the best word to choose as I love the dora now and how it is. But with my ever present mind of seeking knowledge I go back and look things over. So I proposed this. If I am wrong well chalk it up as a learning experience but don't contribute it to the LW whine. I am just seeking answers.
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Originally posted by GRUNHERZ
Everyone shut up. This is turninig into another luftwhine .
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AGJ, I'm not accusing you or anyone else of whining. Hazed made an inquiry about that word, I merely answered.
If the data is credible, and Pyro thinks it bears inclusion, hey, great. I like the Dora too, I think it is a very capable plane in it's current form. Was it even better than we have? Who knows?
I've said before, and I will say it now...........I don't trust any test flight data from the German side as more credible than similiar test flight data by the Americans or British about their own planes. Somewhere, somehow, a myth started that the Germans kept impeccable records and that anything authored by them is like being told by God that they make no mistakes.
Just like American aircraft manufacturers, there was a race to stay alive in the airplane business, and I would not put it past someone to doctor or fudge numbers to impress someone in the aircraft procurement section of the LW.
Let Pyro plug those numbers into the flight model and see what turns up. Current technology enables us to plug in HP numbers and other important data and find out just what a plane is really capable of doing. I trust his system to tell him if performance is really up to par, or if someone somewhere fudged the numbers a tad to make the plane look better.
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Layman's question:
I've often wondered.. what's the difference between a 'wet WEP' and 'dry WEP'??? :confused:
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Hi Kweassa,
>I've often wondered.. what's the difference between a 'wet WEP' and 'dry WEP'??? :confused:
It's an American slang term for augmented power including resp. excluding injection of power boosting liquid.
I assume it originated with water injection (which was used both with piston and with jet engines), but transferred to afterburners as well, "dry thrust" being engine thrust without afterburner and "wet thrust" with afterburner.
The power boosting liquid in the latter case obvioiusly is jet fuel :-)
Regards,
Henning (HoHun)
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top
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yarrrrr! (bump)
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Originally posted by eddiek
Somewhere, somehow, a myth started that the Germans kept impeccable records and that anything authored by them is like being told by God that they make no mistakes
It's not a myth. Apparently you've never had to do any research with wartime test data, and/or have never had a chance to compare non-German WW2 test documents with German test documents. Note here that I'm not saying that North American test data for the P-51 isn't to be trusted - it is. But in general, the Germans were known to be very thorough with their testing of everything. The same can't be said for Allied testing of captured equipment, for example.
At the end of WW2, the U.S. Army found that German test data on captured American weapons (in this case gun performance vs. armor plate) was 'better' than the U.S. data due to German testing procedures, etc.
The data most often seen on LW aircraft is test data dealing with introduction of the aircraft into combat, i.e. very reliable in terms of 'combat use applicability'.
Your comment that 'German aircraft manufacturers were fudging data to stay in business' has no validity. Do you understand how aircraft contracts were awarded in Nazi Germany? No comparison to the U.S.A. during WW2 (which was a good thing for the Allies).
Mike/wulfie
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At the end of WW2, the U.S. Army found that German test data on captured American weapons (in this case gun performance vs. armor plate) was 'better' than the U.S. data due to German testing procedures, etc.
Ouch this is totaly wrong.
Especially regarding penetration data of guns.
German test requirements for penetration values were tougher than all Allied guidelines.
i.e. if a german test mentioned that a gun had a penetration capability of 80mm at 500m, it meant that 100% of all testshots passed through those 80mms.
The french i.e. already gave a gun a certain penetration value if only 50% of the fired shots passed through.
And if you compare test reports of captured vs. non-captured planes, you will notice that german planes most often fly pretty close to the given performance datas.
Some numbers published after the War came just from Allied sources (i.e. William Greens speed data for the FW190D9 comes from a british flight test, but Green made a little fault as he always gave this speed with MW50, while the Brits did the test without MW50, cause they had none).
The only really notable difference you can find is usually in Sowjet flight tests. There all captured planes usually perform significantly worse than in factory data. But on the other hand, no Sowjet fighter that fell in German hands ever managed the Sowjet factory data.
And i dont believe this to be propaganda, cause i.e. the P51B pretty much hits the US factory data in a german test.
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Naudet I think he meant the data was more accurate, not whether it was more optimistic or not.
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Originally posted by Naudet
Ouch this is totaly wrong.
Especially regarding penetration data of guns.
If we were talking about the same thing, you might be correct.
However, we are not. :)
I'm referring to the Germans testing with actual 'issue' ammunition, and several other examples as well. In '42 and '43, the U.S. was testing with 'match' ammunition for it's AT weapons (in the U.S.A.). When the ammunition actually being used by the troops in the field wound up being not of the same quality, incorrect performance and usage data wound up being given to the U.S. troops at the front.
Even with the example you cite, maybe you thought by 'better' I meant 'showing better performance'? This is not the case - I meant more accurate under field usage conditions. I think there's a language barrier here. :)
When it comes to testing for effective range, using '100% penetrations' is the data you want your crews to have. They can still fire from beyond effective '100%' range but they know that at a specific and certain range, vs. a specific target, they are going to damage it.
I've interviewed German, British, Russian, and U.S. AFV crewmen from WW2. This is partly what I base my opinion on.
Mike/wulfie
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Ah, so you actually mean, the german test data was of better quality?
Meaning, german test procedures produced more reliable data for the "User"?
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Sort of. What I'm saying is that in many cases the German testing produced better product when it came to combat equipment. They took certain things much more seriously than other Nations, which led to tactical information and improvements that helped their guys in the field a great deal.
For example - the British examined armor construction techniqes of captured German AFVs. The Germans did this and actually tested for 'block series' flawed armor. This let them know things like '41 series T-34s could be damaged/'mission killed' by big HE rounds (armor plate used in '41 series T-34s was rampant with casting faults), but KV-1s could not (not due to armor thickness, but armor quality of KV-1 plate was better than T-34 in '41).
I think it was a misunderstanding between you and I - I totally agree about the difference between what the Germans considered a 'penetration' and what other Nations did. This extended to combat aircraft by the way - German pilot armor was '.50 proof' on some aircraft, which actually meant it wouldn't fail to .50 BMG fire, period. The British considered some late war Spitfires to be '20mm proof' from the rear in certain areas. But by their definitions, the Germans would have called it '20mm resistant'.
The test data for the Germans was of better quality is some cases, from what I have seen. This mainly dealt with armor penertation, armor, etc. And in some cases mentioned above, like when comparing Russian captured aircraft data to the real thing. The Germans had a vast network with the purpose of recovering downed Allied aircraft and rebuilding them to 'combat ready' standards, for use in testing and also for 'special operations' type applications (SB-2s flying technicians out of Stalingrad in the face of Russian air superiority, etc.).
Basically, someone said that German testing could not be trusted. In general it certainly could, and in some (mainly gun/armor) cases it could be trusted more than other Nation's testing.
The U.S. tested the 75L38 of the early Shermans and the 76L51 of the M10 vs. captured German AFVs. But they did the majority of these tests in the U.S.A., using new ammunition. The actual ammunition being used overseas was of lesser quality. The result was U.S. AFV crews having flawed 'tactical intelligence data' during '42 and '43. When the Germans tested AFV weapons, they fired 'issue' ammunition in all cases, which gave very realistic/applicable results. That's just one example of several.
To sum up - there's no reason LW or German factory test data should not be trusted (contraty to what some have implied). However, I do believe that if the data on a test doesn't match AH, it's almost certainly not a case of 'bad data' being used for the AH FMs. Sometimes I think the limitations of PC code limits accuracy of FM a little, and I also think that sometimes the AH guys have several sources, some of which are not available to the players. I've seen that same group of guys fix FM problems when they were shown to exist. If there's a problem with the D-9, it will eventually be addressed (if it can be).
Some examples of 'FM bugs' I distinctly recall the HTC guys 'finding and fixing':
WB: F6F flaps were not generating proper drag. Error found and fixed (think about that - they pegged that the F6F was keeping E too well when maneuvering in the vertical with flaps deployed...).
WB: P-38 propwash was 'too powerful', giving the P-38J too much rudder authority when fighting in the vertical at low speeds (alot of 'P-38 aces' in WB sucked after this was fixed eheheh). Think about that one as well...nailing down that the P-38 rudder was working too well at low speed, in the vertical, etc.
Pretty esoteric problems to track down in my opinion.
Having said all that, I'll tell you that emailing data and FM questions is the way to go. Avoid the whole BBS argument altogether. If your data is good, and you present it well, and there really is a problem it will eventually get fixed in my opinion. Posting it to (any) BBS is always going to get a negative reaction from some.
Mike/wulfie
(edit) p.s. Naudet - I think the best way to put it is that in some cases (mainly gun/armor) German testing was of a higher standard. The comment that Fw tests are certainly 'skewed' to look better to win aircraft contracts flies in the face of everything known about the WW2 German aviation industry.
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Now i got you Wulfie. And i apologize for the missunderstanding from my side.
I think AH D9s model is pretty correct. Speed and Climb are mostly on the point, the last issue that might need some more investigation is dive performance, and that is for the whole FW190 Series in AH.
What is really sad is, that many Rechlin testdocuments (together with other GE testsites) were destroyed. Rechlin should have the best data on german planes, as they actually tested production maschines.
These tests were down to either verify the performance data the manufacturer gave and to examine the production spread (no idea if that is the right term, they tested multiple productions machines to see how much average difference in perfomance there was).
Also the testsites were the place were captured airplanes were examined and put through multiple tests.
One very interesting fact is that German Testsites had "Beutetreibstoff" (capture fuel), so that they could fly the US planes i.e. on high Octane USAAF fuel.
As far as my knowledge goes about german test procedures, they actually did everything possible to get a realistic picture of the equipment.
To me german performance charts are as trustworthy as US or Britisch ones.
Edit: Wulfie, saw your answers in the FW190-A9 thread, could you drop me an email, as i am also one hell of a D9-maniac and have spend lots of time researching this plane. Would like to question/discuss a few things with you personally.
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Thanks for the info. I don't have time to research an answer now, but we will be doing an extensive review of planes and making corrections if needed as part of 2.0 development.
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Thank you Pyro for the response and that you will look into this. Please keep us up to date on things when you have the time.
!
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Btw Pyro, if you need scans of the FW documents were those number came from, drop me a line. Somewhere i should have a complete scan, not only the charts but also the calculations pages.
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Thank you very much.
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I think mainly and I've seen this for a while AH's Dora is more consistant with '44 Doras and some of the better numbers seen about the Dora are '45 doras yielding 2k + HP w/MW50.
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Originally posted by Pyro
Thanks for the info. I don't have time to research an answer now, but we will be doing an extensive review of planes and making corrections if needed as part of 2.0 development.
Pyro, thanks for the response.