A few Questions About the F6 Hellcat

[eddiek]

Guys, I talked with Pyro on the phone about this very same subject, the side-by-side tests Grumman pilot Corky Meyer did in 1943 with an F6F and an F4U.  When I mentioned the discrepancy in speed, and asked Pyro if he was aware of it,  his only response was "Uh-huh", end of subject as far as that conversation went.
Mr. Meyer spent several months testing the two planes in side by side comparisons and above 5000 feet, their performance was "identical".
In a recent article, he described the feeling the F6F gave you, climbing at 120 mph, 3600 fpm climb rate........excellent view, etc.
I don't look for HTC to do anything to the F6F FM anytime soon.  They go on "official" test data, and if the Navy was truly playing mind games during the war, I seriously doubt anyone will find anything official that substantiates Meyer's tests.  I have read article after article about how aircraft manufacturers put out skewed data to attempt to get more plane orders (Curtiss Aircraft comes to mind first, followed by Bell), but never anything harsh or uncomplimetary about Grumman.
"The name Grumman on an aircraft or a part has the same meaning as sterling on silver."--Vice Adm. John S McCain, CDR Naval Operation Pacific Fleet, 1944.
Check out "Flight Journal" magazine, April 2002 edition, or
www.flightjournal.com for more articles from Corky Meyer.

[Hooligan]

I am sure HTC has high quality data on the F6F that they based the FM on.  If you want to see changes to the FM then produce the documentary evidence so that HTC can evaluate it.  That is the way it works, and plenty of changes have been made in the past when people came up with the evidence to support their claims.

Hooligan

[H. Godwineson]

Hooligan,

The figures developed by Naval Air Intelligence during WWII ARE statistical data.  I have seen them published in more than one source over the years.  If NAI's data isn't good enough then perhaps the bar has been set too high. NAI's job was to provide the most accurate performance data possible to our combat pilots operating in the Pacific.  I would think this would preclude NAI from becoming involved in the political disputes and wrangling that went on between the Navy pencil-pushers and the aircraft manufacturers.

HTC has done a magnificent job in developing Aces High.  It is, by far the best combat flight simulation game yet developed.  Also, they are not content to rest on their laurels.  Indeed, they are continually striving for improvement.  Aces High is quite an accomplishment for HTC considering the paucity of funds and resources available to such a small company.  It is this continual striving for excellence that leads me to hope that they will modify the F6F's flight model and therefore correct more than 50 years of error.

Regards, Shuckins

[Sikboy]

Originally posted by H. Godwineson
Hooligan,

The figures developed by Naval Air Intelligence during WWII ARE statistical data.  

I think Hooligan might be looking for a publication source for this data. I'd be interested in seeing it as well.

But I'd also like to put forth the cautionary statement that I've mentioned before in other posts about upping the performance of a plain based on a single data source:

There might not be a holy grail of data. It is possible that HTC models based on multiple sources. Considering the wide range of performance data on each airframe, this is the approach that makes the most sense to me.

I love the hellcat, and personally, I don't want to see it changed.

-Sikboy

[humble]

Mathman.....

one of the most impressive things about the F6 to me is its rudder authority. I've found you can sucker a con into attacking you...."hang your tail out"....then flick it out of the way and use the incredible dive acceleration to continue the rudder reversal and chase em down. I havent looked at your site in a bit and didnt know if you'd spent any time on that. I know you've mentioned it more than once in other threads.

[Urchin]

Starting to sound like a typical Luftwhiner post to me.... so where is everyone?  Shouldn't you guys be in here ragging on these folks?

[AKDejaVu]

Originally posted by Urchin
Starting to sound like a typical Luftwhiner post to me.... so where is everyone?  Shouldn't you guys be in here ragging on these folks?

Well... not really Urchin.  Nobody has called HTC biased.  I also haven't really seen anyone insist that changes be made or they'll quit.

Besides... they aren't talking about Nazi planes.

AKDejaVu

[Steven]

Did he say "paucity"?  Dang, I gotta dig out the ol' Websters!

lol

[Hooligan]

Shuckins:

All I'm saying is that if you really believe the F6F FM is incorrect then you should do more than tell HTC what a report said.  Produce the report and show it to HTC, then maybe a change will be forthcoming.  

You said:

If NAI's data isn't good enough then perhaps the bar has been set too high.

Well if they aren't willing to change an FM based on NAI data they don't possess then I hardly think the bar is too high.  Part of the criteria for basing an FM on certain data would be that they would actually have to see the data in question, wouldn't you agree?

Hooligan

[Sikboy]

Originally posted by Urchin
Starting to sound like a typical Luftwhiner post to me.... so where is everyone?  Shouldn't you guys be in here ragging on these folks?

Hey, I'm keeping up my end Urchin lol.

-Sikboy

[H. Godwineson]

Hooligan,

Your point is well taken.  The data from Air Intelligence has been used by various authors over the years (Unfortunately, not by enough of them.) in their technical histories of the Hellcat.  I first ran across it in an article about the F6F in the October 1974 edition of Wings magazine.  The latest that I have seen it reprinted was in a technical history of the Zero fighter (Can't remember the author's name off-hand, but he had several interviews with Saburo Sakai) which I purchased back in December.

I am certain those reports are still on file somewhere, but getting an actual copy of them would be about as difficult as finding dragons teeth.  I recently e-mailed Barrett Tillman asking for information about Hellcat armament.  He graciously replied to my questions.  I think I will fire off another e-mail to see if he knows how to obtain a copy of these reports.

By the way, if I had known that using the term "paucity" would cause any confusion I would have watched my language!

Regards, Shuckins

[lazs2]

Over the years I have seen a lot of data and a lot of comparisson tests where hellcats and hogs were tested with other planes like 190A5's and p51B's.  The Corsair allways rolled much faster than the hellcat, climbed about the same and was faster at all alts.   Turn was about the same with the edge given to the hellcat .The -3 hellcat actually climbed a little better than the -5 because it was lighter.

A lot of different props and versions and boost levels were used in a lot of the tests.   the Corsair came equipped with at least 3 different props that I know of.   The corsair and hellcat used the same engine with a different carb and intake ducts but with identical HP.   The Corsair had the best ailerons of any plane in the war and the wing root junction contributed to it's higher, low level speed.    The average of most tests I have seen gives the Corsair about a 15-20 mph edge at both alt and on the deck.   Using navy test data the Corsair was  about as fast as the 51b and outclimbed it.   Both the hellcat and corsair handily outperformed the 190.

Thing is... I wouldn't mind seeing a faster hellcat but a real case could be made for HTC being "right" in this instance.
lazs

[Widewing]

Originally posted by TMASTadon
Ok, I'm making a post here with more holes in it than a piece of swiss cheese as far as varifiable statistics and reference material but here it goes anyway.

Several years ago (and here's where the memory fails me) I read an article in an aviation magazine (I MAY still have the mag somewhere in my house, but it'd take a dedicated Search & Rescue to find it) but the article was written by a Gruman test pilot who flew for Gruman during the war. The Navy was displeased with the F6's roll rate and speed in comparison to the Corsair's so they asked them to test the two planes head to head to see what was causing the differences and to "fix" the Hellcat. This may be the same test that Shuckins was referring to. What they discovered was that the F6 WAS just as fast as the F4U, it was just the the indicator they used (not the dial instrument but the actuall indicator that registers how fast the wind is moving through it). The other thing they discovered, concerning the roll rate, had something to do with the wing postitioning at the wing root I believe (its been a LOOONG time since I read the article and I'm NOT an engineer which they corrected as best they could. This brought about the F6F-5 model with a better roll rate than the -3 model. SO! At least according to the writtings of that Gruman test pilot who flew BOTH the F6 & the F4U under identical situations there was NO difference in the speed of the F6. I'll try to find the magazine if I still have it.
  The article also gave a humorus story of how he tried to a "Skip-Hop" take-off in an F4U (something you could do easily in an F6) and nearly took out a row of parked planes and barely got the plane back under controll before plowing into a hanger full of mechanics and planes.
  I loved the F6 in AW and was ALWAYS fumming about the slow speed they gave it in AW. They had the -3 modeled and I was always complaining that they needed the -5 with the better roll rate and true speed of an F6. I'm glad to see the F6 IS faster in AH but STILL not as fast as the F4U. But then the only advantages an F4U would have over an F6 is climb rate, roll rate and better E retention.
  Oh and while I'm here does anyone know which canopy it is we have here in AW? I know there were several canopy's for the F6 and the later war one was much less like a birdcage type.

Sorry to have hijacked your thread Fowler. I too strongly recommend reading Maths article on Netaces. Its an excellent piece and truly had me missing my ole kitty and wanting to work harder to get better with it in AW.

Corky Meyer wrote a piece about this for Flight Journal magazine. I have the article and can contact Corky should HTC wish to talk to him. Corky was the Senior Test Pilot on the F6F-5 program, as well as the F8F program.

To improve roll rate, Grumman incorporated an aileron spring tab system in the F6F-5. For details, see Diz Dean's "America's Hundred Thousand". There is also data available on the NACA server as well.

My regards,

Widewing

[H. Godwineson]

Flight Journal reprinted the article by Corky Meyer entitled "Navy Taste Test;  Hellcat vs. Corsair" in a special edition called "Fighters."

In a side-bar to the main article, Corky talked about the advances made in supercharging during the 1920's through 1930's.  The two-stage supercharger installed on the Hellcat and Corsair were first used on the F4F.  Below are some of the comments from that article...

"The two-speed supercharger was geared to the crankshaft and attached to the rear of the engine;  it augmented the main stage and boosted service-ceiling altitudes to over 30,000 feet while increasing level-flight performance to 325 mph (F4F).  Because the fuel/air mixture was so highly compressed when the two stages (high and low) were added to the main stage, large radiators/intercoolers were needed to cool the air going into the carburetor;  this prevented detonation and pre-ignition, which would ruin an engine rapidly.  Octane limits were now required to be as high as 145.  Fortunately, the U.S. was way ahead of its enemies in developing octane ratings over 100.  This new superchager now required a three-position handle next to the throttle.  The handle had "Main," "Low," and "High" inscribed on it and was shifted as the altitude requirements dictated."

"The Hellcat and Corsair were both equipped with the same R-2800 engines.  Their level-flight performance now exceeded 400 mph and they had service ceilings of 38,000 feet..."

"The P-47 Thunderbolt and the Lockheed P-38 had turbo supercharging that gave them service ceilings of 40,000 feet and a 460 mph level performance.  These aircraft and engine combinations did, however, take much longer to develop, they were much heavier, and they required long, complicated ducting to maintain proper weight and balance.  An airplane had to be designed especially for such installations.  The P-38, for instance, took five years to reach combat.  The Grumman F6F-3 only took two years and one month to become combat ready."

There you have it guys.  A first-person account by an expert witness who certainly should know the facts.  If asked, I'm sure Corky could produce statistical data to back up his statements.

Regards, Shuckins

[Sikboy]

It's an interesting quote to be sure, but, in my opinion, it leaves a bit to be desired as far as conclusive proof that the F-6F5 should be remodeled. Perhaps it is addressed in some other part of the test, but this passage makes no mention of what models are being tested. If we just went by engine type (which seems to be what we are going by) then the F-6F3 and the should have been capable of 400+ MPH. This would be the first time I've ever head this projection.  This is a narrative account of a flight test from long ago, by Grumman's test pilot. I really don't see how anyone could use this to make/change a flight model, expecially when it seems to conflict with most of the other data collected on the subject.  This is much like the time someone used a narrative account of a Kurt Tank flight test of the Dora to show that the D9 should be controllable up to the very edge of the speed of sound. It makes for great reading, but it conflicts with the rest of the data on hand (or at least we must assume that it does, or else HTC is just making things up as they go).

At least that's how I see it.

-Sikboy