Author Topic: Myth or fact > F8F (Read 16138 times)

Crumpp · « **Reply #120 on:** December 07, 2005, 04:17:55 PM »

Here Neil,

This is the last time I ever screw with someones homemade chart. Using your scale, each tick mark is 5mph. Anything less than that is extrapolated, for example 417mph is shown in the solid read line by spliting the difference between 415 and 420.

I dug out the data and made some corrections. The lines on that graph are rather fat and unclear.

When both aircraft are equipped with racks, the Bearcat has a definate advantage down low. I only shifted the "Erhöhte Notleistung" curve to match the historical data points. You were not off by much at all but enough to show the aircraft were equal for a large chunk of the envelope.

At medium altitudes the FW-190A9 is equal when equipped with ETC 501.

In a clean configuration with the FW-190 at Take Off power and the F8F at emergency, the comparision is similar. Most likely due to the weight and higher drag of the ETC compared to Grumman's hardpoints.

Using the 15-20kph average gain for "Erhöhte Notleistung" would put the FW-190A9 equal or slightly ahead throughout much of the envelope.

As we all know, aircraft performance is a range over a guarenteed percentage from base data. Kind of makes this type of down to the last MPH comparision silly.

Quote

Here's some wing load data: Bearcat = 53.1 lbs/sq ft; Fw 190 A-6 = 46.3 lbs/sq ft.

The FW-190A8 and FW-190A9 fighter variants both have 48lbs/sq ft wingloading at take off weight. Of course it changes for other configurations.

All the best,

Crumpp

HoHun · « **Reply #121 on:** December 07, 2005, 04:30:08 PM »

Hi Shorty,

>Hi, first time poster, long time lurker.

Good first post, and follow-ups! :-)

With regard to my "copy" statement: It has to be read in the original context which directly addressed a statement talking about "the copy of design and/or artistic style".

I definitely wasn't thinking of a carbon copy, but a "free" (functional) copy along the lines of individual design elements, design philosophy and geometric proportions (which would be the equivalent to "artistic style" in aircraft design, I guess).

Do I understand you correctly that the F8F does not have the same single-piece spar as the Fw 190 that makes the rear spar an auxiliary spar in nature? Then I was wrong on the close relation between the two aircraft with regard to this specific design feature.

I still consider the F8F similar enough in geometry and layout to consider it a "free" copy of the Fw 190, but as "free copy" is not a clearly defined term, it's up to everyone to decide which degree of "freedom" he accepts in a "copy" :-)

Regards,

Henning (HoHun)

HoHun · « **Reply #122 on:** December 07, 2005, 05:33:17 PM »

Hi Krusty,

>When (of all people) Hohun threatens to put me on his ignore list (as if I give a rat's arse) I gave up. I knew no matter how absurd and without merit their defiant claims were they'd never even listen.

Please apologize my lack of patience when confronted with the "silly" statement. Your posts never before had struck me as unfriendly, so I should really have provided a more accurate description of the technical similarities I saw instead of going "fangs out" on the first occassion.

The sad thing is that my patience has been worn down by what I perceive as a general trend towards unfriendliness on this board, and I'm afraid that as a non-native speaker, I sometimes over-react.

I assure you that I have taken your above "sigh" as a sign that you posted the "silly" statement out of genuine disbelieve that someone would actually think the F8F and the Fw 190 are related, and not just as a rethoric device to make the opposition look bad (as I, failing to give you the benefit of doubt, had originally assumed).

I hope that you accept my apology, and am looking forward to future disagreements ;-)

Regards,

Henning (HoHun)

ShortyDoowap · « **Reply #123 on:** December 07, 2005, 07:19:33 PM »

HoHun, thank you for the respectful reply. I understand your position now.

AFAIK, the Bearcat had a spar constructed in substantially the same manner as the Hellcat - web and cap strip construction, with the wing group consisting of a center panel constructed in one piece and running through the fuselage. The wing fuselage assembly was made by lowering the fuselage over the wing center section and attaching the two assemblies.

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Neil, do you have a top speed for the F8F-1 on the 115/145 PN fuel? Your chart shows a SL speed, but not speed at altitude. Thanks.

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The climb rates listed are somewhat confusing. The Vought aircraft data sheet shows an initial climb rate for the XF8F of 5,850 fpm at 8,800 lbs and with 1,600 rds of ammo. It doesn't say if that XF8F listed is one of the two prototypes designated XF8F powered by the R-2800-22W engine, or one of the 23 developement aircraft also designated XF8F powered by the R-2800-34W engine.

The F8F-1 manual is confusing as well. The climb chart doesn't mention the engine rating, but the entire manual is devoid of any WEP ratings. Other charts show performance at Military Power and mention at the time no WEP ratings had been specified. So I suspect these are climb times at Military Power rating as well. It shows a climb time to 5,000 feet in 1 minute. 2.13 minutes to 10,000 feet, 3.36 minutes to 15,000 feet, 4.8 minutes to 20,000 feet, and 6.6 minutes to 25,000 feet.

Of course, there is the National Air Races event which featured a stock Navy F8F-1 climbing to 10,000 feet in 94 seconds. Apparently, the only modification to the plane was rigging it so WEP could be reached with the gears down. Even so, that's an astonishing climb rate.

So, the Bearcat was a fast climber, but its hard to make out where all these different climb rates come from.

agent 009 · « **Reply #124 on:** December 07, 2005, 07:28:10 PM »

It would be worth noting that the Hellcat & Corsair had narrow track landing gear. & the wide concept, ( even though earlier aircraft had it, Zero etc), was not copied by Grumman til after flying the FW 190.

MiloMorai · « **Reply #125 on:** December 07, 2005, 08:00:34 PM »

Quote

Originally posted by agent 009
It would be worth noting that the Hellcat & Corsair had narrow track landing gear. & the wide concept, ( even though earlier aircraft had it, Zero etc), was not copied by Grumman til after flying the FW 190.

At 12'1", I would not call the F4U's landing gear narrow track.

The F6F had a track of ~11'6".

The 190 had a track of 11'6". (3.5m)

So one was the ~same and the other ~6" wider than the 190.

The P-51 had a track of just over 11'.

agent 009 · « **Reply #126 on:** December 07, 2005, 08:29:39 PM »

Corsair photos do not seem to bear this out. nor do Hellcat photos. & we are talking about Grumman aircraft, not Mustangs.

Crumpp · « **Reply #127 on:** December 07, 2005, 08:31:33 PM »

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At 12'1", I would not call the F4U's landing gear narrow track.

The F6F had a track of ~11'6".

The 190 had a track of 11'6". (3.5m)

So one was the ~same and the other ~6" wider than the 190.

The P-51 had a track of just over 11'.

More importantly you need to examine the ratio of the aircraft span to the landing gear track.

Corsair = 3.39:1

F6F Hellcat (using Milo's figure of 11'6") = 3.72:1

P51 (using Milo's number of 11') = 3.38:1

FW-190 = 2.95:1

The FW-190 had substantially wider gear track than any of the compared aircraft. The US Fighters are just much larger dimensionally.

Anybody know the gear track of the Bearcat?

All the best,

Crumpp

ShortyDoowap · « **Reply #128 on:** December 07, 2005, 08:48:15 PM »

From hinge to hinge, it's 11 feet.

Crumpp · « **Reply #129 on:** December 07, 2005, 08:55:41 PM »

F8F Bearcat = 3.25:1

Wider than any other US Fighter compared. Assuming no splay and the 11 foot track is correct.

All the best,

Crumpp

ShortyDoowap · « **Reply #130 on:** December 07, 2005, 08:59:38 PM »

Out of curiosity, was was the Thunderbolt's?

Wing span 40' 9 15/16".
Gear width 15' 7"

Something like 2.60:1

MiloMorai · « **Reply #131 on:** December 07, 2005, 09:04:07 PM »

Quote

Originally posted by agent 009
Corsair photos do not seem to bear this out. nor do Hellcat photos. & we are talking about Grumman aircraft, not Mustangs.

Get some scale drawings and a ruler.

The P-51 was included for comparison.

F8F > 3505mm/11'6"

Crumpp · « **Reply #132 on:** December 07, 2005, 09:24:48 PM »

Quote

Out of curiosity, was was the Thunderbolt's?

That is correct. I got 2.56:1.

All the best,

Crumpp

straffo · « **Reply #133 on:** December 07, 2005, 11:51:23 PM »

Quote

Originally posted by Crumpp
More importantly you need to examine the ratio of the aircraft span to the landing gear track.

Why ?

In this case the B52 will have an non calculable ratio does it make unable to land ?

Debonair · « **Reply #134 on:** December 08, 2005, 12:27:02 AM »

I hate to be a nattering nabob of negativity, but this thread has taken a dangerously moronic turn