P-47M/N?

[Lephturn]

Give me either one of these awesome beasts to kill 262's with please.  

Guys... how about an American perk?  We don't have one.  I want one bad.  The 47M or N would be the perfect choice.

BTW... I wouldn't be totally surprised if HTC slipped one into this build without telling us anyway.  

[gripen]

Originally posted by Daff:
It's worth noting that while loking at the factory performance, the 56th had already modified the wastegate on their existing P-47D's to the same manifold pressure as the P-47M (72"),so I'm not sure how big an improvement the P-47M really was.

This tale just goes on and on. Why don't you post somekind of hard evidence that the P-47Ds with R-2800 B-series engines could be succesfully hot rodded above say 65" without overheating problems and limiting service life of the engine to the couple hours. And if these hot rodded P-47Ds really existed, why they did not use them for V-1 hunt? Why on earth the P&W redesigned whole engine for the C-series if similar performance was available reliably with B-series engines? Why the Republic made the P-47M if the D could do same? The Pilots of the 56th FG were certainly pissed when they downgraded to the unreliable P-47M    

gripen

[ 08-15-2001: Message edited by: gripen ]

[-ammo-]

Originally posted by gripen:


This tale just goes on and on. Why don't you post somekind of hard evidence that the P-47Ds with R-2800 B-series engines could be succesfully hot rodded above say 65" without overheating problems and limiting service life of the engine to the couple hours. And if these hot rodded P-47Ds really existed, why they did not use them for V-1 hunt? Why on earth the P&W redesigned whole engine for the C-series if similar performance was available reliably with B-series engines? Why the Republic made the P-47M if the D could do same? The Pilots of the 56th FG were certainly pissed when they downgraded to the unreliable P-47M    

gripen

[ 08-15-2001: Message edited by: gripen ]

Jealousy

[eddiek]

Same principle applies to all here, gripen.

Naudet posted about the 109 and 190 "pilot comments" about the turn rates.  Are we supposed to take their word, just because they were LW fliers?    

Widewing posted that he had interviewed USAAF personnel who corroborated the wastegate mods......and he also explained the reason for no "official" documentation.  Even in wartime, even when your life depended on your plane's ability to fight and still get you back home alive, you were expected to adhere to "official" policy.  Nevermind that turning up the engine power on your plane kept you alive, to "admit" to doing so on an official level meant possible courtmartial.  Just goes to show how different the perspective was for the front line pilots and the REMF's.  Front line, you did what you had to do to stay alive.  REMF's looked at the little #'s on paper and said "make it work with this", even if those #'s made no sense in the real world of combat.

Whether or not you believe it, that is your choice.  You don't have to.  FWIW, I personally believe things gotten firsthand from pilots who were there.  Robert Johnson, Gabreski, others who flew the Jug felt it was at least the equal of anything the Germans had in the air, after the Jug was set up to fight and live.  IMO, the P47M was merely the application of the lessons learned in combat, i.e. engine mods for higher performance.........
You say we need hard data.  Define hard data for me?  Hard data to me means not only factory spec sheets, but also pilot accounts and crewchief/member accounts of what the plane was like.  Test pilots did not push the planes to the limits of the flight envelope like combat pilots did.  If the crewchief "turned up the wick" on his assigned plane, to be honest, he didn't give a flip about the regs, unofficially, of course.       His main concern was seeing that bird and it's pilot come back home to roost, and if he had to do it on the sly, so be it.
My thinking is that to get the most accurate picture of what a plane was like, you need to look at both "official" stuff and also the "unofficial" stuff.  That way you get a better perspective on what it was like for the pilots, not just what the bean counters "said" it was like.
Though it would cause an uproar, I wish Pyro would set up a Jug just for the CT, with paddle prop, water injection, and higher than stock MAP and HP........just to see how it fared and if it would really honestly upset game balance.  To be sure, til they adjusted, the LW guys would be freaking out, but I don't think the plane would be untouchable.  It would make it more challenging for sure, but not invincible.  And to offset the Jug mods, give the 109G6 the MW50 and GM-1, just to be fair to all involved.  But, those are just MY wishes..........  

[eddiek]

Well, nix the above idea for the CT out......

Just got off the phone with HiTech, and I did not realize just how much work would be involved in modifying even seemingly simple performance mods/enhancers.  Those guys have to redo the FE, and IMHO, they already do a bang-up job at this game.  I kinda feel guilty after making the posts about the performance mods to the various planes........if they added all the stuff we say we want ( and by "we" I mean all of us, LW, USAAF, USN, RAF, IJN, etc.) they would never get anything done.
My suggestion:  Fly what ya like, like it is, enjoy it as it is.  HTC can't please everyone all the time, and when it gets right down to it, all we are doing is splitting hairs.  
Aces High is best sim out there, bar none.

[Hooligan]

If these mods to the jug were common then there will be documentary evidence.  If you want HTC to model this, then evidence has to be presented to them.  I could say that I interviewed both German and US vets and they all agreed that a) the jug could not exceed 100mph or b) that it easily exceeded 500mph.  I certainly hope that HTC wouldn't just take my word for it.  They need better evidence than just my (or anybody's) word.  Surely some of this stuff about modifying waste-gates etc... is written down somewhere in somebody's memoirs, or a Republic memo, or a book about the P-47 etc...  Point HTC to the documentation so they can evaluate it and perhaps they will make the mods to the FM some day.

Hooligan

[Widewing]

Originally posted by gripen:


This tale just goes on and on. Why don't you post somekind of hard evidence that the P-47Ds with R-2800 B-series engines could be succesfully hot rodded above say 65" without overheating problems and limiting service life of the engine to the couple hours. And if these hot rodded P-47Ds really existed, why they did not use them for V-1 hunt? Why on earth the P&W redesigned whole engine for the C-series if similar performance was available reliably with B-series engines? Why the Republic made the P-47M if the D could do same? The Pilots of the 56th FG were certainly pissed when they downgraded to the unreliable P-47M    

I suspect that the reason you are struggling with over-boosted engines is that you don't understand how and when over-boosting occurs.

Simply stated, just because an engine is capable of extreme power output does not mean that it will operated continously at those manifold pressures.

Let's assume that Bob Johnson is accurate when he reports being able to obtain 72 in/hg in WEP. How long would he operate the engine at such high boost pressure? The answer is, minutes.

My car's engine can operate safely at 7,500 rpm, 900 rpm above recommended redline. How often will I do that? Not frequently. Moreover, I won't run the engine at that speed for very long either.

Likewise, a pilot flying a P-47 with reworked wastegates, will only over-boost the engine when faced with an emergency situation. At all other times, he will adhere to normal power settings.

Does this make more sense now?

My regards,

Widewing

[Sancho]

Well by that explanation, HTC would need to do some recoding to make the souped up engine work (on any plane), rather than just allowing higher manifold pressures for unlimited time.  As it is now, there is no penalty for running full throttle all the time... engines won't overheat and die on you.

[eddiek]

Widewing, hate to say it, but, the ball is in your hands now.

If I recall correctly, you stated here or on another board that you had interviewed Pappy Gould, Johnson's crewchief, and other pilots who were there.
Maybe it's time to share some of their comments on the P-47 and factory vs actual engine settings?       PLEASE?????  

[Daff]

"Surely some of this stuff about modifying waste-gates etc... is written down somewhere in somebody's memoirs, or a Republic memo"

First, apperantly all the Republic's documents regarding the P-47 was destroyed when Fairchild bought them up...

Secondly, Johnson did state in an interview that he had the wastegate modified to 72" and could do 300mph IAS @ 30k.

There's one former crew chief on the P-47 Advocates board that's been hinting that a book will coming out shortly, which will explain these things in detail.

About engine life:  P&W ran a benchtest, with a a severly overboosted engine, and it ran for a long time (36 hour straight?). While it  was certainly ready for the scrapyard afterwards, it did do it without any problems.

Gripen:
"Why on earth the P&W redesigned whole engine for the C-series if similar performance was available reliably with B-series engines? Why the Republic made the P-47M if the D could do same?"

If you re-read my post, you would see it was stated as a question.

Daff

[Hooligan]

Daff:

Not all of the republic documents are destroyed.  Somebody took some of them home.  Some crewchief kept a few folders as memento's and they’re moldering in an old footlocker in his grandson's attic.  Some of them ended up in Air force archives.  Transcripts of interviews with names and dates etc… exist somewhere.

I really have only one point in this:

Some documentary evidence must exist and if these modifications are going to be modeled in AH a sufficient body of this evidence must be discovered and presented to HTC.  This isn’t Widewing’s problem either.  He doesn’t even play AH so why should he go to all the work to gather the documents and make them available?

To be useful, any discussion of this issue past this point must take the form of:  “Where do we find the necessary documentation so that we can present it to HTC?”

If somebody really wants this change to AH they should be getting in contact with the crewchief you mention and asking to copy his sources.

I wish you the best of luck.

Hooligan

[Buzzbait]

S!

The discussion of hotrodding of P-47`s etc. is also in this post:
 http://www.hitechcreations.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=9&t=002340

[gripen]

Well, well, these hot rod tales appear to be my best troll so far here   Anyway...

eddiek,
Just look current D-9 thread, first I pointed out with easily verifyable evidence that Naudet's theories about Mustang's and 109s turning performance were wrong or based on selectively choosed data. After that I have pointed out several times that there should be hard data to prove his theories, just like I have done here. And actually I'm willing to believe that some P-47D were really modified without further evidence, but according to my sources, anything over say 62-65" should have showed up in the overhaul statistics. And still, HTC crew have made very clear that there should be data which can be verified. BTW actually there is documented data about field modifications atleast on the Airacobra and P-51.

Widewing,
Be cool!

Daff,
Well, the 56th FG was very near to convert to the P-51 because they had so much problems with the P-47M. Actually some P-51s allready arrived to the units for training. The 56th needed better fighter than the P-47D they had.

gripen

[-ammo-]

Originally posted by gripen:


Daff,
Well, the 56th FG was very near to convert to the P-51 because they had so much problems with the P-47M. Actually some P-51s allready arrived to the units for training. The 56th needed better fighter than the P-47D they had.

gripen

All units were replacing their existing AC inventory with Pony's. The 56th was equiped with the P-47 till the end because of circumstance and hi level decisions. As the war closed and the allies were staging op's out of mainland Europe bases, it only made sense for the 56th to stay with the jug. All the parts, labor, and other logistical stuff required to maintain them were present. The pony units that were prior P-38 and P-47 units were for the most part already transitioned to the pony while still in England.

I do not doubt however that the 56th would have been transitioned if the war would have went on. Parts and logistics to support the large number of existing P-51 units could be divied out to them.

[Widewing]

Originally posted by eddiek:
Widewing, hate to say it, but, the ball is in your hands now.

If I recall correctly, you stated here or on another board that you had interviewed Pappy Gould, Johnson's crewchief, and other pilots who were there.
Maybe it's time to share some of their comments on the P-47 and factory vs actual engine settings?       PLEASE?????  

Actually, I conducted several long telephone interviews with Bob Johnson several months before his unexpected death while visiting family in Lawton, Oklahoma. Bob related that Pappy Gould had incorporated some changes to the waste gates (Probably involving either stretching, replacing or shimming the springs) that allowed the engine to pull insanely high manifold pressures. Gould also hand polished exhaust ports, carefully fitting intake tubes and exhaust stacks to maximize flow characterisitics. Gould also waxed Johnson's Jug to a high gloss, using fillers to eliminate surface irregularities in the skin of the fighter. This last item was good for 5-8 mph on any WWII vintage fighter. Other factors include prop indexing. All P-47s arriving in a combat zone did so with the props indexed for 93 octane fuel. This was because there were many locations away from the war zone where 100-130 avgas was not available. Smart crew chiefs would immediately re-index the prop, which would allow the highest MAP to be pulled. I do not believe that the USAAF ever issued a technical directive that this be done. Largely because the possibility still existed that lower octane fuels may still be used.

I will be contacting the president of the P-47 Pilots Association to see if he has any members that can shed additional light and be specific about field modifications.

By the way, you asked me about Republic's testing of the C series R-2800 engines, where they ran the engines a very high boost, generating up to 3,600 hp. The test documentation survived in the custody of C. Hart Miller until it was obtained by Lowery Brabham. With the death of Brabham, his papers became the property of his family, who still maintained the materials as late as 1994. The aicraft used to perform the extreme high power tests was S/N 42-27385. Subsequent to completing the testing, both the airframe and R-2800-57 were judged to be "war weary". The worn out engine was returned to Pratt & Whitney for teardown and evaluation, the Jug was relagated to hack duty. This was largely due to using this aircraft to test the new dive flap installation. As a result, the airframe had been subjected to more than 100 high speed dives, frequently exceeding Mach .80, or damn near 600 mph. Dr. Herb Fisher performed many high speed dives while testing transonic props for the Propeller Division of Curtiss-Wright. He established the P-47's terminal dive velocity at an insane Mach .83, which is really honkin'. I have some of that test data and have posted it on the web.

My regards,

Widewing