Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: F4UDOA on March 01, 2001, 09:44:00 AM
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Gents,
I have posted the data in PDF format on my web page. Here is the URL
http://members.home.net/markw4/MSWF4UDATA.pdf (http://members.home.net/markw4/MSWF4UDATA.pdf)
It is 6 meg so I cannot e-mail to anyone as I had promised. It's 29 pages long, all in img format, not text. I listed them in the order of the report so the data is spread through out the report. It gives comparisons to these A/C.
F4U's
-1
-3
-4 <== Oct 1944 and revised April 1945
-5
F2G-1
F6F-5
F7F-1
F8F-1
P-51B <==only
P-47D
P-38J
Enjoy!!
Pyro,
If your going to model the F2G, F8F, F7F or especially the F4U-4 please look at these docs.
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Thanks DOA!
[This message has been edited by wells (edited 03-01-2001).]
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Got it. Thanks!!!!
-Westy
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If anybody is having trouble reading some of the text let me know. It is a little easier reading the paper docs.
Later
F4UDOA
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All I can say is.....
SWEET! (http://bbs.hitechcreations.com/smf/Smileys/default/biggrin.gif)
Real F2G data.... wow!
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Vermillion
**MOL**, Men of Leisure
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real axcellent f4udoa
looks like teh f4u in aces high pretty well modeled,but the p47 is getting sorely shafted in its speed at low level.
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Zig,
Yeah, the P-47 they tested is a fast bird. It's weight was only 14,000lbs so I wonder what varient it was? I think it was a D20 with a uprated engine to 64" of manifold. The only thing about the F4U-1 that could be changed in AH is the climb. Notice the initial climb at military power is 3K per minute. It's about 2700fpm in AH.
But the thing that stands out for me though is the stall speeds and drag numbers. The stalls in AH are all to high
P-51B=.017
F8F-1=.019
F4U-1=.020
F7F=.020
P-47D=.022
F6F-5=.023
P-38J=.028
The F4U numbers are broken down in detail including cooling drag. Niklas had mentioned a while ago that he didn't thing a F4U could really do 360mph on the deck because the drag was to high. I guess there is the answer.
Also the numbers on the F4U-3 are amazing.
487MPH at 27,500FT and 378 ot sea level. And that was a production bird BTW with 30 being built and delivered. It is amazing that the F2G has gotten so much attention over the years when the F4U-3 actually had better performance above sea level, while the F2G had a top speed of 397MPH on the deck and only 426MPH at alt. when the power curve fell off.
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I think that fuel octane has been swapped over with N1K2 and F4u (http://bbs.hitechcreations.com/smf/Smileys/default/wink.gif)
obviously F4u needs higher octane which N1K has and N1K needs low octane from f4u...
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Well those stall speeds are all recorded at -3/4 fuel and -3/4 ammo. Given the CLmax's you would get from them, and that they are trying to simulate landing conditions, I think those are flapped stall speeds anyway.
Sable
352nd FG
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Sable,
I am sure they are all flapped speeds but not all at landing weights and not powered stalls either.
Look at page 27 on the F4U-1 performance. It list the power off stall for the F4U-1 as 89MPH with a Cl max of 1.90(correct for F4U-1 NACA full flap). Then compare that too this doc dated Aug.1944
http://www.geocities.com/slakergmb/id73.htm (http://www.geocities.com/slakergmb/id73.htm)
Listing the Gross weight (12,000lbs) stall at 87.5mph and the empty stall at 82.2mph power off. And it matches almost perfectly with the note that it is power off. Also the F4U-1 pilots manual list the power on full flap stall at 66Knots or 76MPH.
Regardless of this the stalls of all of the A/C listed in the report are to high in AH especially with flaps. An issue I have brought up many times in the past. That is flaps are not creating enough lift.
Later
F4UDOA
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Ahhhh I see. I'm not an AH flyer, so I didn't see anything too shocking in the stall speeds. (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
Sable
352nd FG
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F4u I think the answer to the P-47 weight being a bit low is that it was loaded with 305 gallons instead of 370 gallons of fuel.
From the tables in AHT on pages 281 and 285 I see a D-27 to D-40 should develop 2600HP at 64" manifold pressure. Missing the 65 gallons in the Auxilary Main Fuel tank, it would weigh 14,021 lbs. It seems the 47 in the test you found was one of these.
Hooligan
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65 gallons of fuel != 15 mph speed reduction
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CC Hooligan,
That was one fast Jug.
Zigrat,
I thing that extra 65 gallons of fuel was carried in an inflatable rubber raft dragging behing the A/C (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
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Originally posted by Hooligan:
F4u I think the answer to the P-47 weight being a bit low is that it was loaded with 305 gallons instead of 370 gallons of fuel.
305 gallons in the maximum internal capacity for all Jugs prior to the P-47D-25-RE.
Fuel capacity is another strong clue pointing to Vought testing an older razorback D model re-engined with a later model, uprated engine.
My regards,
Widewing
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From AHT -- Republic and USAAF data for a D-23 through D-26 (14500 lbs) with 2300HP gives it a top speed of about 338-345. 355 for a 2600HP (14,000 lb) D-30 seems pretty consistent with this (actually a little bit slow (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)). I believe that another 400 lbs of fuel would only affect top speed of the D-30 by 1 or 2 mph but climb would drop by 100ft/min or so.
Hooligan
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F4UDOA, all I can say is, Thank You! I really appreciate your taking the time to scan all this and place it where we all have access to it. <S!>
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Sundog
VMF-111 Devildogs (http://www.devildogs.com)
MAG-33 (http://Ripsnort60.tripod.com/M3.html)
'Criticism is always easier than craftmanship.'
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The chart on page 20 of the pdf shows the empty weight of the P-47 at 10,148lbs I think but I can't read it to well. AHT lists the D-25 empty weight as 10,864 lbs, and the razorback empty weight as 9957 lbs. The D-25 has an additional 178lbs of engine and propellor over the razorback in AHT, and 9957+178= 10,135!! That really makes me think that it's an early razoback D model refitted with a late R2800-59 of the 64" manifold preassure variety.
Sable
352nd FG