Author Topic: F4U Vertical performance (Read 544 times)

Jekyll · « **on:** December 12, 1999, 04:34:00 AM »

I just love it when I read some book written by a WW2 pilot where they describe particular performance attributes of their aircraft.

Take the following example, from the book "The Jolly Rogers", by Tom Blackburn, Commander of VF-17. Blackburn is describing a low pass at La Guardia airport in his F4U-1A. Consider the vertical performance he claimed:

"I pointed her down from 5,000 feet and came by, full bore, close aboard the tower at window level indicating 350 knots - 403 miles per hour. I pulled up in a 45-degree climb, slow-rolled to the right, slow rolled to the left, and leveled out at 10,000 feet from the half loop and half roll of the imelmann, which put me on a heading back over La Guardia".

Next time you're flying the Hog in Aces High, put 25% fuel in the tanks and try to repeat this maneuver. Remember, a low pass at about 100 feet altitude, 350 kias, then up in the 45 degree climb. Don't even worry about the rolls, but see what alt you can get to before you stall out

Was Blackburn on crack??????? or did the Hog really have the ability to hang onto its prop in that fashion??

------------------
C.O. Phoenix Squadron
www.users.bigpond.com/afinlayson/index.htm
'feel the heat .......'

juzz · « **Reply #1 on:** December 12, 1999, 07:40:00 AM »

He must have forgotten to mention the RATO units "field modification" he had the mechanics fit to his F4U.

Windle · « **Reply #2 on:** December 12, 1999, 11:53:00 AM »

Well for what it's worth I've seen an F8F zoom climb right out of sight (much more than just a couple thousand feet). IMO I think a 400 mph F4U with good G-force control in thhe pull up should be able to zoom climb to a bit more than 2000 feet before stalling.

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~Lt. Jg. Windle~

VF-17 The Jolly Rogers 8X
Skychrgr@aol.com

spinny · « **Reply #3 on:** December 12, 1999, 02:02:00 PM »

Did you try it with no ammo? That's worth about 820+ pounds; also, he was flying the 1A, which is about 300 pounds lighter than the 1D. Might be a weight difference of over 1000 pounds.

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Spinny, VF-17
8X

wells · « **Reply #4 on:** December 12, 1999, 06:02:00 PM »

Then there's the parts that he failed to mention because it adds nothing to his 'story'...(in brackets)

I pointed her down from 5,000 feet and came by, full bore, close aboard the tower at window level indicating 350 knots - 403 miles per hour. I pulled up in a 45-degree climb, (levelled off), slow-rolled to the right, slow rolled to the left (while waiting for speed to pick up again), and leveled out at 10,000 feet from the half loop and half roll of the imelmann, which put me on a heading back over La Guardia.

Jekyll · « **Reply #5 on:** December 12, 1999, 06:19:00 PM »

Wells, ?????

-ik- · « **Reply #6 on:** December 13, 1999, 12:24:00 AM »

lol, busted.

in actual combat reports pilots were astounded when they saw a prop fighter climb only 1500 feet in a vertical climb and level off.

Pongo · « **Reply #7 on:** December 13, 1999, 09:13:00 AM »

Seems that Wells forgot to mention them too. But they would have added much to his story..

MiG Eater · « **Reply #8 on:** December 13, 1999, 10:14:00 PM »

Is there an indication of what altitude the tower was at? How far down from 5000 feet did he dive? I have the book here but the page(s) wasn't listed for quick reference. Tower altitude above mean sea level would make a big difference in the height gained from the ground in a zoom climb.

MiG

214CaveJ · « **Reply #9 on:** December 13, 1999, 10:51:00 PM »

If memory serves (dinnae feel like pulling out the Terminal Arrival Procedures book for NY right now =) LGA's field elevation is only 10-20 feet msl (above sea level) and the control tower is like 150-175ft high. Using those figures, he dove about 4800 -4850ft to pass the tower windows at ~150 -200ft msl

Duckwing6 · « **Reply #10 on:** December 14, 1999, 04:27:00 AM »

windle I hope you meant 20.000 feet

i'd be asonished to see a 400mph airplane only zoom to 2000 feet..

Well for what it's worth when i do a rope drop (glider towing) from the PA18 Super Cub i get to fly, at 130mph (which is pretty much as fast as you can go without overreving the engine with the climb prop) and from 100 ft AGL (2400 MSL) it zooms up into pattern altitude with a 45° climb that's 1000-1200 ft AGL or 3300-3500 ft MSL..
I admitt the plane is WAY lighter (in that condition maybe 1400lb) but it only has 150 HP (almost double the power loading than an F4U with a rough estimate of 10.000lb and 2200HP), and is WAY draggier .. so the inertia alone of a 10.000 lb airplane traveling at 400 mph should carry you WAY further than 2000 ft especially if you do a low G pull up.

SC-Duckwing6

Jekyll · « **Reply #11 on:** December 14, 1999, 06:45:00 AM »

Sorry MigEater. The story is on page 92 of the paperback edition I have.

------------------
C.O. Phoenix Squadron
www.users.bigpond.com/afinlayson/index.htm
'feel the heat .......'

jedi · « **Reply #12 on:** December 14, 1999, 12:35:00 PM »

Sounds like a bit of literary license to me

And of course I've NEVER heard a fighter pilot "embellish" the capabilities of "his" plane. And of course ANY plane a fighter pilot has scored kills in is, by definition, the best plane in the world

So, he's cruising, say, 300 knots. He dives from 5000 feet. Laws of Physics say he's going, at best, about 300 knots again when he gets BACK to 5000 on his climbout. So he bleeds off 150 more knots for another 2K or so of altitude, and then he's at 150, close to his best climb speed. Now he can maintain 150 for another 10000 feet if he wants (but his "zoom" is pretty much over). If he puts the nose down a bit at this point and gets 180 knots, he can probably coax it over the top into an Immelmann, ending up at 10000 ft.

So, not quite a fish story, but not the pure truth either, I bet.

--jedi

G. Gibson · « **Reply #13 on:** December 14, 1999, 07:38:00 PM »

According to "Technical Air Intelligence Report No 62." Technical Air Intelligence Center NAS Anacostia, D.C. "Interim Fighter Comparison Chart" The F-4U-1a averages a Climb Rate of approximately 3800 feet per minute up to 20000 ft., out climbing the P51-D's best climb of 3500 feet per minute up to 10000 feet, then progressively lower. The P51's rate of climb then can not even compare to the F4U1a at higher altitudes.

I don' know if this helps or not. I just know what I read. But always heard from WII pilots that the F4U could out climb, but not out run the P51. But it is definately not so in AH's model.

CombatWombat · « **Reply #14 on:** December 16, 1999, 02:17:00 PM »

Your numbers seem spot on to me. I just know people will intrude with huge climb figures for the 51 or poor ones for the corsair. I just dont get it? It happens EVERY TIME we discuss reletive plane performance? All the flight sims I've played have placed the corsair as the better climbing aircraft. If they all have the same basic gist to them I'd think they are somewhat credible? Then you get the crazies running amok insisting the reletive climb rate is correct!

Oh well...enuf ranting.....for now.....

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According to "Technical Air Intelligence Report No 62." Technical Air Intelligence Center NAS Anacostia, D.C. "Interim Fighter Comparison Chart" The F-4U-1a averages a Climb Rate of approximately 3800 feet per minute up to 20000 ft., out climbing the P51-D's best climb of 3500 feet per minute up to 10000 feet, then progressively lower. The P51's rate of climb then can not even compare to the F4U1a at higher altitudes.
I don' know if this helps or not. I just know what I read. But always heard from WII pilots that the F4U could out climb, but not out run the P51. But it is definately not so in AH's model.

Author Topic: F4U Vertical performance (Read 544 times)

spinny

214CaveJ

G. Gibson

CombatWombat