What angle of flap deflection for takeoffs/landings would have been used with WWII shipboard fighters, namely the Grumman Hellcat?[sm=confused.gif]

I'd like to experiment with manually-adjusted flaps set before trial flights, set from inside the fuselage. What's the best procedure ..... try a little and gradually increase on succeeding trials?

Photos in the Squadron Signal book show a LOT of flap for takeoff. About equal to angle of the line on the fuselage between the foot holes in the sides. 45° or more!
The flaps probably wouldn't have been used at all taking off from an airfield.
If by "manually set" you mean your flaps will be down all the time, you won't like it in flight!
One of the last photos in the book shows an F6F drone with a 2000 # bomb on a steam catapault during the Korean War. No flaps!
.
Flaps were probably a necessary evil before the steam cat on a carrier.

Flaps, at "short field" setting were needed for takeoff from carriers durrng WWII.

The modern jets need flaps on launch from the steam cats... even though the cat can accellerate a fully loaded aircraft for 0 to 120 knots in under 2 seconds... the heavilly loaded aircraft are still at the verge of stalling when they leave the deck.

Actualy, the catapaults could accellerate the aircraft more, but the pilots are on the edge of gray-out to black-out due to the forces in the launch as it is. They've clocked test load shots off of catapults in excess of 150 knots. (test loads don't have thier own jet engine's aiding the acceleration... and they are designed to be at least as hard to launch as any airplane you could hook to the catapult.)
**********

Flying around with flaps down... not a great idea. If yo want a working flap lever in your cockpit, connect it by linkage to the flap servo. (or drive it with a mcro servo Y-harnessed with the flaps)

For test flights, I would not put the flaps down at take-off. Just be sure you have plenty of airspeed and lift the aircraft off gently.

One thing I see almost every time I go to the field is people who won't abort a bad take-off run. They zig-zag all over the field and instead of cutting the throttle and taxiing back for another attempt, they take off with too little airspeed, cross-wind, down-wind, you name it.

Point being that you should be ready to abort if you don't like the run. Too much work in a scale ship to try to force it in the air.

If you feel compelled to use flap on the test flight, I would say no more than 10 - 15 degrees.

I can shed some light onto this as a pilot. But I am not an aerodynamic engineer. Flaps begin by adding more lift than drag. It reaches a null point where the added flap setting adds an equal amount of lift and drag. Beyond that point there is a greatly diminished amount of lift added and the induced drag is rises at a rapid rate.

The civilian aircraft I fly sometimes have TO flap settings of 10-15 degrees. Some are even as high as 20 degrees. I have not seen higher than this. I do know that some heavy aircraft and warbirds have higher TO flap settings. I would be very carefull though. You are flying a model aircraft and not a full scale Hellcat. The median point of added lift versus drag is around 20 degrees +/- 5 degrees for most light plane aircraft flaps.

I also know that many aircraft have been crashed on touch & go by the failure to remove landing flap setting upon adding throttle. With landing flaps set, you add power, the plane pops off the ground early and jumps out of ground effect. Only to mush back to earth nose down. Not a happy ending...

Because most models have unrealistic power to weight ratios you can likely get away with more TO flaps than the model wants. I would also test the setting in the air for severe trim changes before landing or taking off with them. Be realistic in your models power assesment.

CHUCK: Thanks for the real-world views on flap angles and their use.

ALL: Here's why I posted the original question:

I want to build the Guillow's 32-3/4" Hellcat, converted to e-power. I envision using contest balsa throughout (except for LE, TE and spars), with a planked fuselage, all-sheet wings (top & bottom) and all-sheet tail parts. All control surfaces would be built-up and tissue-covered to simulate the full-scale fabric covering. I thought initially to omit the landing gear to save weight since I would be hand launching over grass. As I examined the kit plans, box art and pics on various web sites, it struck me that the model would be pretty much a "plain Jane" with little detail appeal. I then began to consider including LG down, cockpit open, flaps down, pilot able to turn his head left & right, linked to the aileron servo ..... just putzing around, looking "scale". Too KOOKY? [sm=spinnyeyes.gif]

Since I only have a 4-channel TX, the flaps would be set INSIDE the cockpit using a lever and pawls similar to the cutting height adjustment on a riding mower. I'm learning from this thread that first I need to get the model to FLY and then to experiment with lowering the flaps. The sole purpose of this is to add some realism to the model. It would then look like a warbird returning for a carrier landing, OR: a a Hellcat whose squadron is about to ship out, the pilots practicing touch-and-go's at a naval air station.

Any comments?

I would lock the flaps in the up position until I had a 5 ch radio for the model. Otherwise... sounds great.[8D]

The method you describe for controlling the flaps... would be somewhat difficult to set up, and could cost you the model.

Yuo could if looking for some added interest... link the cockpit canopy to the flaps... whent he flaps go down, the canopy slides open. (but thats going to add weight... and might not be a good idea on a small electric aircraft.)

Basically it's too ambitious a project for the size of the airplane.
Get familiar with the way the first one flies without the landing gear or flaps or anything else.
You might decide the next one needs to be larger.