F6F and F4U flight models switched?

[flakbait]

Got bored earlier today and raided Zeno's to watch the flick on the F6F. From what the narator said, it stalls at 65 knots (71.5mph) clean. Is still completely flyable all the way down to 90 knots (99mph). It enters a loop at only 160 knots (176mph) and can pull slow rolls clear down to just above stall speed. It will fly itself off the runway, no flaps, around 65 knots (85 maybe? sound wasn't clear). I clearly remember the trim settings "elevator, zero. aileron, zero. rudder, 1.5º right".

Another point they made was that it had almost no tendency to swing during takeoff. Our F4U doesn't swing on takeoff, is very controlable down to just above 100mph, and can do just about anything at the above speeds. Did the FMs for the two get switched? I know our low-speed control needs desperate work. I can't get an F6F, any flap config, down to 80mph without it dropping into a stall. The nose gets real heavy at 100mph; it shouldn't do that until 75mph.

Just curious really. Gonna check Zeno's flick on the F4U against the info F4UDOA posted later tonight.

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Flakbait
Delta 6's Flight School
"For yay did the sky darken, and split open and spew forth fire, and
through the smoke rode the Four Wurgers of the Apocalypse.
And on their canopies was tattooed the number of the Beast, and the
number was 190." Jedi, Verse Five, Capter Two, The Book of Dweeb
 

[wells]

Keep in mind that AH uses CAS, not IAS.  The correction factors for the F6f are quite high, 15 knts or so.  You need to add that to get what you see in AH.  A better airspeed installation on later F6f's fixed the problem for the most part, such that when flying formation with a Corsair, they read the same speed.

[funked]

I also noticed that our F6F has a violent flick stall, a characteristic of the real F4U.  I've read that the real F6F had a gentle stall.  I think you might be on to something.

[This message has been edited by funked (edited 01-11-2001).]

[flakbait]

Funked our F4U stalls the wrong wing and it does stall very gently. Almost like a 109. The F6F video showed one stalling; it was quite gentile. I know the F4U required 14-16 turns to recover from a spin, and dumped the wing like a 190 does. Suddenly and violently. Our F4U can be recovered from a spin within 6 turns; less than half the normal requirement. Both Joe Baugher's page and Zeno's video state plainly the F4U will snap hard into a stall because the right wing simply drops.

On takeoff the F6F they showed lifted off smoothly at a relatively low speed. No more than 100mph. I can only do that in a Zeke with full flaps (which are SNAFUed anyway). All in all I think the F4U and F6F flight models got swapped. Either that or their "FM Program" is seriously flawed. If it was, I couldn't prove it since I don't have a copy of it.

Hmm, I just thought of something. If a prop turns clockwise (cockpit view) wouldn't the right wing drop first in a stall? The corkscrew of air is blowing down on the right wing, and blowing up on the left. This would give the left wing extra "lift" as it were. So the right wing would dump first. Our F4U, F6F, and every other aircraft that has a clockwise-turning prop should drop the right wing. They drop the left wing in a stall.

Am I right? Wrong?


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Flakbait
Delta 6's Flight School
"With all due respect Chaplian, I don't think God wants to hear from me right now.
I'm gonna go out there and remove one of His creations from this universe.
And when I get back I'm gonna drink a bottle of Scotch like it was Chiggy von Richthofen's blood and celebrate his death."
Col. McQueen, Space: Above and Beyond
 

[flakbait]

Ok, I goofed on the wing stall. The F4U stalls the left wing, or so the narator said. Joe Baugher's page says right wing, and a spoiler was added under the right wing. Could be a goof I don't know. Anyhoo here's my short-hand notes from listening to the film at Zeno's:

 

idle 750 rpm

normal takeoff
rudder 6º right
aileron 6º right
elevator 1º up

45" 2,700 rpm
20-30º flaps

carrier takeoff
rudder 6º right
aileron 6º right
elevator 1º up

43.5" 2250 rpm rated cruise

2330 32" under 14,500 ft
2150 29" best cruise

Stall power off, landing config, 30 flaps
77 knots
74 knots power on

Clean stall power off
85 knots

3600 max rpm

7g max

25º flaps best turn under 175 knots

loop 210 knots
immelman 210 knots
slow roll 180 knots

30º flaps landing, tail high
ONLY touch brakes when 3 points down

Time to watch the F6F film again. I'll post my notes on it here in a bit.


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Flakbait
Delta 6's Flight School
"For yay did the sky darken, and split open and spew forth fire, and
through the smoke rode the Four Wurgers of the Apocalypse.
And on their canopies was tattooed the number of the Beast, and the
number was 190." Jedi, Verse Five, Capter Two, The Book of Dweeb
 

[flakbait]

My short-hand notes from the F6F film at Zeno's:

 

Normal takeoff

elevator 0
aileron 0
rudder 1.5º right
flaps up

tail lifts at 2000 rpm
45-50" for takeoff
60 knots liftoff

carrier takeoff

elevator 0
aileron 0
rudder 1.5º right
full flaps (no positions, Spit-type flaps)


52.5" 2700 climb
44" 2550 rpm normal

15,400 ft max power

1500 30" under 5,000 ft

stall-type:

power on, clean
62 knots

power off, clean
65 knots, nose up

Landing w/flaps, power on
53 knots

Landing w/flaps, power off
58 knots

390 knots max, 7g max

slow roll, 170 knots
loop, 190 knots
immelman, 200 knots


Landing:
Flaps down, 110 knots or lower for gear
80 knots landing speed
3 point landing will touch at 60-65 knots

Carrier landing:
75 knots, flaps down

Looks to me like they were switched. Most of the info in the F6F film regarding stall was more like our F4U. So in the stall and torque aspects, our F6F is really an F4U. The above F4U specs in the film are from a -1 hog. Probably an A model, since the narator plainly said drain the wing leading-edge tanks first. Did you know the F6F used a starter cartridge? I didn't until I watched this little 20 minute movie he's got.

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Flakbait
Delta 6's Flight School
"With all due respect Chaplian, I don't think God wants to hear from me right now.
I'm gonna go out there and remove one of His creations from this universe.
And when I get back I'm gonna drink a bottle of Scotch like it was Chiggy von Richthofen's blood and celebrate his death."
Col. McQueen, Space: Above and Beyond
 

[flakbait]

I'd appreciate some help here guys. From another post by F4UDOA the flaps on both the Corsair and Hellkitty are WAY off. Full flaps should make both planes lift off almost like a Harrier in clean config. Makes me think just how badly these two models were mixed/swaped. Low speed handling needs a serious fix. Even with that extra 15 knots it comes out to around 80mph; you can't get an F6F that slow. If you do the thing will sharply dump the left wing.

The F6F feels like part Fw-190 and part F4U. It's got the 190 and F4U's vicious stall, F4U's torque, and the same screwed up flaps.

Just as a reference, 1.1 is the multiplier for knots to mph.

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Flakbait
Delta 6's Flight School
"With all due respect Chaplian, I don't think God wants to hear from me right now.
I'm gonna go out there and remove one of His creations from this universe.
And when I get back I'm gonna drink a bottle of Scotch like it was Chiggy von Richthofen's blood and celebrate his death."
Col. McQueen, Space: Above and Beyond
 

[funked]

1.15

[funked]

PS I don't really think they confused the two planes.  I just think the stall behavior is worth investigating.

[Jigster]

Oh and a note about the starter cartridge...they only used these when there was no air pressure in the reserve tank for the air starter. It was a back up system in case the compressed air tank was bleeding off.

[Jigster]

 

Originally posted by funked:
PS I don't really think they confused the two planes.  I just think the stall behavior is worth investigating.

Like the P-38?  

[flakbait]

Going through the PDF file for the F6F-5 from the Navy history site. I found the following info about takeoff runs:

800 feet normal.
384 feet with a 25 knot wind and full flaps.

This document gives 72.2 knots (83mph) for power on stalls. 79.2 (91mph) knots for power off stall.

The next page shows various curves for takeoff run, range, speed and climb. At 12,740 pounds combat weight the F6F will lift off after a run of 600-700 feet. Shorten that to 300-400 feet with a 25 knot head-wind. Takeoff speed is not listed in this document. I'm going to stick with 75 knots (86.25mph) since it's in the middle.

I'll post the link for it when I track it down again. There is a document for the F4U-4 but I'll jump off that bridge when we come to it.

Here's the link. I'm going to do some testing tonight in the TA in regards to takeoff run. Now only if we had some distance markers on the runway for stuff like this.
 http://www.history.navy.mil/branches/hist-ac/fighter.htm

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Flakbait
Delta 6's Flight School
"For yay did the sky darken, and split open and spew forth fire, and
through the smoke rode the Four Wurgers of the Apocalypse.
And on their canopies was tattooed the number of the Beast, and the
number was 190." Jedi, Verse Five, Capter Two, The Book of Dweeb
   

[This message has been edited by flakbait (edited 01-13-2001).]

[Weave]

Don't know about the flight models being switched, but something is definatly catiwumpus with these two planes.

Yesterday in the MA I was supporting an attempt at 28 in an F4U (yes I am the ocassional chog dweeb).

I was engaged with a nik, and at the first merg, I attempted a high yo yo. I was into the verticle at 280 TAS, alt about 1500ft when the tail slid out from under me. It was like the tail feathers had been shot off, but I had heard no strikes. They were in fact still there, as I was able to recover, however by then the demon nik had ample time to come around... and you know the rest of that story.

This morning I was tangling with a zeke at 9 in the MA. I was flying the F6F. We engaged at 5k alt, my speed was 260 TAS. I attempted a level turn to the left, not terribly hard mind you, (not even close to blacking out) and I found myself in a horrible ccw spin.
Throttle back, stick forward, opposite rudder got me out of it in about 6-7 turns. Unfortunatly I immediatly went into a cw spin. Same drill and I recover in about the same amount of turns.

By now I'm on the deck, but the zeke has been drawn off by another whom he quickly dispatches. I get set up for our next encounter.

We approch each other, he is at my 11 oc and maybe 1.8k alt below me. I bank left and start to turn into him as we merg. My speed is 260 TAS. I tighten my turn abit, and the left wing drops out from under me! No stall warning, again not even close to blacking out. My fuel load at this time was just over 50%, no external ordinance, so I wasn't too heavy.

I've noticed the wind doing some real strange things lately. Could this be the answer? Donno, but went back to the La5 and had none of these problems.

Weave

[Jigster]

I hope eventually there is some kind of buffet model worked into the stall model...it might help alot at the onset of accelerated stalls. Same with compression.

[flakbait]

Took two films yesterday morning in the TA. Loaded 50% fuel, no flaps takeoff, climb to 10k then stall and spin both aircraft. The F6F and F4U stalled with power off very closely. I hadn't intentionally spun an F6F before, so I let the aircraft settle a bit before commencing with pullout. The F4U was a bit harder to pull out of the spin, and required a LOAD of back-pressure to keep level during the stall. I'll do some power on stalls and spins later, but here's the film.

F6F and F4U stall/spin film

Both films go from takeoff to recovery.


-----------------------
Flakbait
Delta 6's Flight School
"For yay did the sky darken, and split open and spew forth fire, and
through the smoke rode the Four Wurgers of the Apocalypse.
And on their canopies was tattooed the number of the Beast, and the
number was 190." Jedi, Verse Five, Capter Two, The Book of Dweeb