OK, I'm new to flaps.... never had a plane with them before. In flight, when the flaps are used, the airplane balloons dramatically and requires down elevator to keep it level. This is normal and was to be expected. I've never tried to take off with flaps, but based on the in flight test above, should I expect to have to feed in DOWN elevator during the run out to get the tail to rotate and start flying? Then ease the elevator back to neutral to as the plane leaves the ground (while decreasing flaps)?

To control the pitch-up when flaps are extended, you might try mixing a little "down" elevator with the flap command, and don't normally use more than about 15 degrees of flap for takeoff, since flaps generate a lot of drag; and you don't want a lot of extra drag when you are trying to accelerate to safe flying speed. Without mixing some "down" elevator with the flaps, you might try trimming the elevators down sufficiently to prevent the pitch-up, then re-trim the elevators as the flaps are retracted. I hate taking off and climbing out while holding down elevator - a moment's inattention can result in disaster.

Use your trim tab. That's what full scale pilots do. I have a GP RV-4 with flaps. When I put them down I know I need 5-7 clicks of down trim. I use the same amount to take off. I recently bought a computer radio and will program the mix in eventually, but for now I do it the old-fashioned way.

On my Cessna 182 Skylane I use flaps all the time. About half as much for taking off than for landing. I have the elevator mixed to add down when flaps are deployed.
Flaps can also help you loop tighter.
Happy Flying


Tom

I have to ask --- why do you want to use flaps for take-off? Models invariably have more power than brains, & getting off the ground is hardly an issue. Getting off the ground with flaps, however, has unexpectedly killed many a nice model. It's "Off we go and -- OH ***** --- damn, I hate it when that happens".

In other words, think twice about why you want to do it -- and if you do, be ready for a moon shot at low airspeed.

HMMMMMMMMMMMM:
BECAUSE I CAN !?!
Been taking off with flaps for over 5 years and haven't had any surprises. If you ask me, it makes for shorter and more stable take offs. I usually won't use them with 10mph or better winds.
My Cessna 182 has a 82" wingspan and has only a 91 4-stroke on it, so not overpowered. Flaps make it more realistic and I use about 25 degrees on take off and about 45 degrees on landings. I also have down elevator mixed in when flaps are deployed to off set the plane's tendency to balloon.


Tom

Oh BTW: Here's a pic.
That little thing on the center of the wing is a glider release.

Tom

Do you have a computer radio? If so, you can mix the down elevator trim to your flap setting, so when you set your flaps for takeoff, the correct elevator trim to keep it from pitching up is also set. When you retract your flaps after takeoff, the elevator trim will go to its regular setting; this way you don't have to continually re adjust elevator trim. It works the same way when you use full flaps for landing.

Why use flaps? Because the plane has them, and it's another skill to work on.

Just had a "Duh" moment. I have the GP RV-4 with flaps, also, and struggle to get it to come down when I extend the flaps. I have an "entry level" computer radio that won't mix flaps and elevator. Never thought of just counting the number of down trim clicks needed to make it stop balooning. Thanks.

Phil