Author Topic: F4U-1D carrier Takeoffs porked? The proof!! (Read 1376 times)

F4UDOA · « **on:** October 08, 2002, 11:36:25 AM »

Heya's

Just trying to take my place in AH as one of the all time whiners.

Anyway I've been doing some testing on the loaded F4U-1D fully loaded takeoff characteristics.

First test.

Auto take off land base no wind full fuel 2K Bombs 8 rockets. Gross weight 15,000LBS.

Observed takeoff runs for speed and distance.

Each notch off flap caused a longer takeoff run proving that the flaps do create drag. This is correct No problem.

The reason Auto take off causes a longer run is because it lifts off at approx the same speed in the F4U which is 120MPH give or take a few MPH. Viewed on external film viewer for exact speed.

Second test.

Same load manual takeoff. It is possible to achieve a much shorter take off run with full flaps.

90MPH appears to be the critical liftoff speed for the F4U-1D fully loaded with full flap.

Third Test.

Move to carrier.

In ten tries I was unable to reach my minimum critical speed by the end of runway for takeoff. Failed each time.

My conclusion based on this was that since the takeoff run for the F4U at 14,415LBS in a 30knot wind should be 509FT then maybe the Carrier deck is just to small for the F4U since HT said the spawn point is exactly 556FT from the end of the deck and the carrier is moving at 35MPH exactly. Granted I am used WEP also which is more power than the F4U would really have so with the extra weight 556FT is about the right distance for a Fully loaded F4U. So based on that alone I would say that the F4U should be able to make it off the deck in Mil power without to much difficutly albeit not much room to spare with manual takeoff.

These points are off.

1. I should not need WEP.
2. The run from the manual is with 30% flap not 100%.
3. a 14,300Lbs bird can do it in 509FT in 30Knots34.5MPH with 30% flap then a 15,000LBS should be able to make it in a 35MPH wind in 556FT with full flaps fairly consistantly from the flight manual which is a rather reliable piece of test data I think.

Here is the Killer.

Fourth test.

Grab a P-47D30 100% fuel 2K Eggs and 10 Rockets this is about an 18,000LBS A/C

Manual takeoff full flap, WEP whoosh!! right off the deck!!

From the pilots manual

The P-47D has a takeoff run at 15,000LBS of 1200FT. More than twice the run of an F4U-1D at 15,000LBS not 18,000lbs which the test A/C would have weight. WTF??

Next the P-38L full load full flaps full fuel 2K eggs 10 rockets.
Approximately a 21,500LBS A/C.

From the manual again

21,400LBS takeoff run 30Knot headwind 34MPH. takeoff run 930FT (300+ft longer than the F4U-1D with equal load)

Auto takeoff hands off!! full flap WEP. Whoosh.
Not even close. Off the deck before the end.

The P-51D failed would not takeoff with a full load.

The Mossie with full bombs rockets fuel made it first try.

The A-20 not only made it off with Rockets and bombs and fuel but made it easily. This A/C out accelerates the F4U-1 like it is standing still. Even with full flaps it made it to 100MPH + by the end of the deck. The F4U could not reach 90MPH!!!.

The F4U was pupose built for short takeoff runs. I keep saying the accleration is porked maybe this will stir some interest. An A-20 with bombs should not out accelerate an F4U-1D off of a carrier deck!!

Here is the F4U data.

P-47D data

SELECTOR · « **Reply #1 on:** October 08, 2002, 12:02:32 PM »

good work.... unfortunatly HTC dont seem to care too much about such matters..we have tried before to get a plane fixed...it wont happen:D

Red Tail 444 · « **Reply #2 on:** October 08, 2002, 12:03:26 PM »

I, have been talking and learning from a member of the VF 101 Grim reapers in Oceana, and according to USN flight data that he researched,

Corsairs landed with 30 degrees of flaps, but in CV takeoffs, only one notch of flaps is needed with max fuel/ordnance loadout.

Speed can be influenced by the amount of yawing, from rudder, compensating from torque, as you roll down the deck, as well as setting too many flap settings which bleed off E due to increased drag.

Excellent research, BTW, more than what I'd make tie for thats for sure.

I can get a loaded corsair off deck, but yes, not 100% of the time. Usually, its from a step in the procedure I forgot about, or did incorrectly, that puts me in the drink.

FWIW, we could use a little more help from HTC regarding the Corsair. maybe a longer CV...I won't even get into engine management

Gainsie

Soulyss · « **Reply #3 on:** October 08, 2002, 12:03:37 PM »

Quote

In ten tries I was unable to reach my minimum critical speed by the end of runway for takeoff. Failed each time.

Are you saying that you were not able to successfully keep the F4U airborn once you ran out of deck space?

F4UDOA · « **Reply #4 on:** October 08, 2002, 12:25:38 PM »

Soulyss,

Correct.

I cannot keep that this flying 100% fuel Bombs rockets.

Even manual takeoff no combat trim.

From watching my attempts on land and at sea I can tell that full flap takeoff speed is approx. 90MPH. If you can reach 90MPH (measured on the digital viewer) you can takeoff. Unfortunately the F4U-1D falls just short of that on a CV.

Again I was able to takeoff from a CV in a fully loaded P-47D, P-38L, Mossie and A-20G.

The P-38 and A-20 were a Joke. They rocketed off the deck no problem. The P-38 will do it hands off auto take off.

The P-38L isn't even in the same league as the F4U-1D in the short takeoff world. It take a third more runway with the same load to lift off in reality.

The A20G is a medium bomber!! it easily outstripped the F4U-1D off the carrier deck. The question isn't how come I can't get off the deck in an f4U. The question is why is it so easy in A/C that shouldn't even be able to do it at all.

BUG_EAF322 · « **Reply #5 on:** October 08, 2002, 12:43:39 PM »

The P38 was a fast accelerating plane.
It also got the best climb speed full loaded.

that should say something.

I believe the P38 was able to take off carriers (there where ideas for it)but the navy never wanted water cooled planes.

For the rest u sound like a Allied Wilbus

Mitsu · « **Reply #6 on:** October 08, 2002, 12:48:49 PM »

im with u bug.

F4UDOA · « **Reply #7 on:** October 08, 2002, 01:18:07 PM »

Bug/Mitsu,

This has nothing to do with the Navy or what they wanted. From the AAF own P-38 flight manual it takes over 900Ft to lift off at that weight.

From the F4U flight manual. It takes more than 300ft less to take off with the same load in the same wind condition.

It really is pretty cut and dry.

ygsmilo · « **Reply #8 on:** October 08, 2002, 01:22:27 PM »

Did you callibrate your throttle before testing?

vorticon · « **Reply #9 on:** October 08, 2002, 01:25:03 PM »

take off spaces are all messed up...i had a easier time getting a c47 up than the f4u

and i have taken the c47 off on a airfeild in about the same area it takes to get a fully loaded hurrc2lese

something seems wrong there

F4UDOA · « **Reply #10 on:** October 08, 2002, 01:31:21 PM »

Here is why I am sure that somethings porked.

Compare the speed of these three A/C at the end of a 556Ft carrier deck. All A/C full flap. Full load viewed on the external film viewer speeds read from digital readout.

1. A-20G speed = 97MPH+

2. B-26 Speed = 93MPH

3. F4U-1D = 88MPH

This is right? Two medium bombers can out accelerate an F4U-1D? Really?

The A-20G is 26,500 fully loaded with two 1600HP engines with a 61 foot wingspan!!

26500LBS/3200HP= Wingloading = 8.28

F4U-1D fully loaded 15,000lbs

15,000LBS/2250HP= Wingloading = 6.67

I will attatch the film for each.

F4UDOA · « **Reply #11 on:** October 08, 2002, 01:34:06 PM »

Yeah a C-47 floats around like a butterfly here LOL.

But on the throttle point. I thought of that. But I'm looking at my MAP. When I engage WEP I get full 60" MAP which is correct. If my throttle where not on full then WEP would not engage.

Also it would affect all A/C tested.

Soulyss · « **Reply #12 on:** October 08, 2002, 01:41:07 PM »

It is possible to take a fully loaded F4U-1D and successfully launch from a CV. I just did it, it's dicey and you do lose alt off the front of the carrier but you can stay in the air.

MAC · « **Reply #13 on:** October 08, 2002, 01:54:06 PM »

Amen F4UDOA!

Thanks for the research. You are NOT whining...you are making legitimate arguments for a long-overdue Corsair Flight Model overhaul/adjustment.

When the History Channel has a program on the Corsair or the Black Sheep, they talk about how they would push the throttle forward and be slammed back in their seats. They talk about how the Corsair would "...climb like an angel returning to heaven."

Ever since the last major release the Corsair takeoff was porked. You used to be able to take off with autopilot and a full load with only 10-20% flaps with NO problems. Try that now!!! Impossible. It's a struggle to take off manually...with a full load and full fuel unless you roll back to the cables.

Looking at historical film and you see Corsairs with full load outs up off the CV several yards before the end of deck.

Keep up the good work. Maybe if we squeak enough.......big maybe.

Thanks again F4UDOA!

MAC

No. 54 Squadron

Vermillion · « **Reply #14 on:** October 08, 2002, 02:04:02 PM »

F4UDOA, try the experiment again without flaps and see what the effect is.

It may not be an issue so much of weight and acceleration, but a factor of how "draggy" the flaps are, and their effect on lift. Which is what I suspect.

The F4U has huge flaps, and may be creating a large amount of drag, but without gaining the correct benefit of lift.

This might be causing the effect you are observing.