Author Topic: Flaps still not working properly (Read 427 times)

F4UDOA · « **on:** December 29, 2000, 11:22:00 AM »

I will just use F4U data since I have the most of it, but I am sure other birds are the same.

Try taking off from CV with a F4U 100% fuel and Ammo no flaps. Relatively simple. Now try it with full flaps and the takeoff run becomes more difficult. It actually is harder using flaps than without?? According to the Pilots manual full flaps should lower stall speed from 96MPH to 76MPH(At 11,300LBS). And with a 40mph head wind to fly into that should be a pretty short takeoff run. Same for the HellKitty too.

It would seem that all birds don't quite stall at the right speed with full flap deflection. The 38 probably suffers the worst because it has the most to gain with the Fowler flaps. However getting an accurate weight for the P-38L fully loaded is near impossible.

Just some food for thought. From the manuals.

Takeoff run
F4U-1D 11,700LBS.
0knots headwind 680FT <==Short
45knots headwind 120FT <==real short

P-38L 17,400lbs
0Knots headwind 1030FT
45knts headwind 300FT

Ever wonder why the P-38 didn't fly off carrier decks??

juzz · « **Reply #1 on:** December 29, 2000, 11:45:00 AM »

What could it do for the USN that the Corsair couldn't? Considering that B-25's were launched from the Hornet... I don't think take-off run was an issue.

CavemanJ · « **Reply #2 on:** December 29, 2000, 12:19:00 PM »

I have a devil of a time getting a -1D off the deck with 75% fuel, 1k eggs, and rockets. Been using 3 notches of flaps (-1C lifts off just fine in that config). Guess I'll have to try full flaps on the next -1D sortie

F4UDOA · « **Reply #3 on:** December 29, 2000, 12:21:00 PM »

The part about the 38's being launched from the deck was just a joke. The short takeoff run was necessary for the fast carriers and times where there was no headwind or if the carrier was disabled and unable to create a headwind. A B-25 probably has better wing loading than a P-38 depending on the load.

My point is really to show that the flaps do not significantly reduce stall. Just tested F6F-5. Stalls about the same as F4U and P38. All three are too high with flaps.

BigJim · « **Reply #4 on:** December 29, 2000, 02:30:00 PM »

The F4U1c will take off with FULL ammo, fuel, 2k of Bombs, and Full rocket load WITHOUT any Flaps being deployed. The F4U1d will not take off under ANY conditions with the above mentioned FULL loadout i.e flaps or no flaps. I have not tried the F6F so can't comment on that one yet. Also I have yet to make a successful trap with either the F4U1d or the TBM (this may however be my poor skill level) but I do find that the F4U1c can be trapped at ANY reasonable attempt EVEN if slightly over speed and FORCED to the deck, no so with the F4U 1d, F6F, or the TBM which seem to explode after I have caught the arresting cable (too fast maybe???). Since I have NO first hand experience with ANY of these planes I can only ask if this is a correct depiction since I have NO actual facts with which to base any comment (other than the game itself)

Fatty · « **Reply #5 on:** December 29, 2000, 02:39:00 PM »

I actually have an easier time getting a full F4u-1d up than a full 1c. I use 2 notches on both, haven't had too much trouble (though I do swoop pretty low coming off the carrier).

Landing I've found the 1d and 1c both pretty tough handling coming in rough, but f6f is a deader easy if you bounce it hard.

Rocket · « **Reply #6 on:** December 29, 2000, 03:31:00 PM »

Jim read my carrier takeoffs in the Help forum.
I regularly take off with 100% fuel, 2 1k bombs and rckts in the 1D with full flaps and wep. She'll drop 20 ft comin off the deck but she flies

S!
Rocket

SKurj · « **Reply #7 on:** December 29, 2000, 07:05:00 PM »

I get off the deck with 2 notches flaps, and wep, in 1D with 1k's and rckts..
Try not droppin flaps til the aircraft has accelerated abit.

AKskurj

Hans · « **Reply #8 on:** December 29, 2000, 10:25:00 PM »

Your not supposed to use full flaps on takeoff.

Full flaps put them down almost vertically, and act more like airbrakes than lifting surfaces in that setting. They're used to slow down steep aproaches for landings.

Try it will half flaps.

Hans.

juzz · « **Reply #9 on:** December 30, 2000, 05:23:00 AM »

Looks like these guys are using full flaps to takeoff...

F4UDOA · « **Reply #10 on:** December 30, 2000, 11:22:00 AM »

Gents,

In the pilots manual for "emergency takeoffs" it say "In case of short field or runway, lower flaps full down. Make a normal takeoff run with nose high".

Also it says in section C. of the standard check for all flights.

Quote

Flaps settings.-For normal operation it is recommended that a setting of 20Degrees be used for take off. Actually, any flap flap setting for 0 to 50degrees(full flap) may be used, the higher settings giving shorter takeoff ground distance. Take-offs with flaps up are easily accomplished with a small increase in run, dispensing with a small inconvenience of retracting the flaps after take-off. In addition the rate of climb immediately after take-off with flaps deflected is inferior to that with flaps up. Takeoffs with high flap setting and at full flap should be made only when it is necessary to obtain the shortest possible ground run. and after more experience with settings increased gradual from the recommended setting of 20degrees. When high flap setting is used the elevator tab should be set slightly tail heavy(about 1degree).

Sounds like full flap is the easy way to go.
However in AH it appears to be exactly the opposite with full flap increasing the take-off run instead of decreasing it. Also the appropriate stall speeds at reduced weight or with flap deflection.

BTW, this is not an F4U rant. I simply have more information for it than any other. The same would be true of the F6F-5, TBM, P-38 and P-51, or any other A/C that had flaps designed for the purpose of maneuvering or to decrease take-off run.

I know HTC has this info. It is just a matter of confirming the issue and verifying the data. Then when they find the time...

Thanks
F4UDOA

If anyone has a copy of the F6F pilots manual I would luv to see a copy of the weight and stall chart in the back.

F4UDOA · « **Reply #11 on:** December 30, 2000, 11:55:00 AM »

Did some testing offline.
First empty no problems
Then two 500lbs bombs no problems

Then all test with
100% fuel two 1000lbs bombs. auto take-off
No WEP
F4U-1D no flaps gear hit water. A/C ditched
F4U-1D full flaps gear hit water. A/C ditched

F4U-1C no flaps barely made it.
F4U-1C Full flap gear hit water A/C ditched

F6F-5 No flap made it.
F6F-5 Full flap, gear hit water A/C ditched.

So essentially The flaps make it harder to take off in a short run. The opposite of what is expected.

Here is a pic or two for your viewing pleasure.

F4UDOA · « **Reply #12 on:** January 02, 2001, 12:44:00 PM »

Punt...

Pyro, any comment??

Ripsnort · « **Reply #13 on:** January 02, 2001, 12:48:00 PM »

Here's my comment...I load the F4U-1D up with 2x1k bombs and rockets, full fuel, give her WEP while holding brakes on, then let her go...just as I get to the end of the deck, I employ 1 notch of flaps, then gear up. No problems.

Duckwing6 · « **Reply #14 on:** January 02, 2001, 02:38:00 PM »

F4UDOA one thing about full flap takeoffs is that you are lifting of WAY back on the drag curve , the means yes you CAN get her into the air (most probably in ground effect) but that doesn't necessarily mean you can actually accelerate to flying speed in this configuration.