I've been flying my US40 and love it. Today for the first time I tried using the flaps on a slow pass and the plane climbed forever! How much deflection should there be for the flaps and should I have any elevator coupled in with the flaps?

You have not really offered a lot of information to go on, but this is all that I can offer. It sounds as though you did not get a manual with your model. Did your RC system come with a manual that would explain the setup of coupled flaps and elevator? It may be that it won't offer how much deflection. Something that the gurus or older more experienced guys at the field may help you with.
Horizon Hobbies' web site has an area that offers the instruction manuals for assembly and setup of the Hangar 9 line. Mine was pretty thorough for the US120. The manuals are downloadable for free. Navigate to that area.
For the setup procedures you will need a method or device that offers measureable indicator marks. Great Planes has such a device to do this with.
I recall that my manual suggested that what it offered was a beginning point and that experimentation will have to follow to suit me.

SA Flyer

I always try first 30° in my tx, is a good starting point!!

I would have to go over the manual again, but I believe it does not mention elevator mix with flaps, only with crow. This set up gives the "straight up" takeoff using flaps. For slow flight try the crow which has the elevator mix and provides much better slow flight on the US 40 than flaps.

The control throws recommended in the manual for the Flaps is as follows:

Degree - 25%
Low Rate - 1 1/4" Down


Hope this helps.............

Nt

for just plain ol' flaps, i've got about 30 degrees (activated by channel 5 switch). they used to be at about 45, but i switched servos and haven't messed with it yet. with 45 degrees, i can nearly hover to a dead stop with no headwind, and the plane will very slowly decend (will fly backwards with a headwind). i can also go straight down from way up while holding just a tad down elevator to counteract the upward push of the flaps and land in VERY short order. when i set up my flaps originally i just went for max throw.
as for flaperons, i've got about 10% mixed in with elevator, and that coupled with flaps will lift off in less than 5 feet. if you are constantly climbing with flaps down you are going too fast! try slowing to almost a stall and then drop flaps, then power up to just fly fast enough to not lose or gain altitude.

I'm using a Futaba 6XAS and had to set the flaps up on channel 5. Even at a real slow pass when I activate just the flaps it will climb almost straight up. I've programed in some down elevator to the flaps and haven't tried it yet. I'm just wondering if it's normal to climb that steep with the flaps down on a slow pass or if there was too much deflection in the flaps.

I'm new to the flaps and the crow feature but loving the plane more every day. To activate the crow I have to activate the flaps and the airbrake. What should I expect?

I tried turning on my flaps on my US 40. I had the flaps dropping 1/2 a inch. I also had some down elevator mixed in with the flaps. Well I had it high in the air, which was good , so I hit the flap switch and the US 40 did a complete nose dive. It didnt try to climb as some ofyou stated. did I have too much down elevator mixed in? I like to use these flaps for landing..........and would like to know how to use them for short take offs. Thanks, JT

JT

Put the flaps down 1 1/4" and no down elevator mix for really short takeoffs. You will have to push it over with the elevator stick when you have your desired altitude and retract the flaps. My elevator down mix for crow is only 1/4", but a great deal of that depends on balance, speed, power setting, etc, so experiment high. With the 1 1/4" down flaps and low power settings you can land it really slow, just remember that when you chop the throttle, it will drop whatever altitude is remaining (tends to strike the prop if you blow it) - it's easier for me with crow for a really short landing. If your radio has the landing mix option - then you can put in the down mix on elevator just for landing and resolve some of the nose high attitude. Hope this helps.

Dave