RV-4 Dipping Problem
 

I'm new to rc flying and am having a problem with my plane dipping during level flight. It's an electric outrunner. Tried flying in calm wind to see if wind was the cause but plane acts the same way. Any suggestions would be greatly appreciated. Plane weighs 22 OZ.
THX Brian

RE: RV-4 Dipping Problem
 

Define dipping. Is it simply needing up trim? I think we need more info.

RE: RV-4 Dipping Problem
 

Plane will be flying level and just dip down like if you used down elevater, then go back to level flight. Have checked controls and everything seems tight.

RE: RV-4 Dipping Problem
 

G'day Mate,
Sounds like a radio glitch, check aerial position, in relation to servos, switch & so on, keep it away from aerial & switch.

RE: RV-4 Dipping Problem
 

Also check for ANY loose parts. Radio or mechanical.

RE: RV-4 Dipping Problem
 

Thanks for the tips . will give it a try.

RE: RV-4 Dipping Problem
 

Is that the 70 inch rv-4???

RE: RV-4 Dipping Problem
 

The plane is a small electric , only 22 OZs. Wing span is 38 in. It's a Great Planes Kit. Powered by a Park 450 Outrunner, 25 Amp ESC , Have used both a 10x4.7 and 9x6 prop.

RE: RV-4 Dipping Problem
 

Has this happened many times, or just once? Are you flying at a Club? Have you done a range Check?

RE: RV-4 Dipping Problem
 

Is the balance correct? I can't tell by your description, but I would check that too.

RE: RV-4 Dipping Problem
 

Since you only mention a singular directional problem, the nose dips, this might point to an overheating or current draw issue with the speed controller, motor, or flight battery.

A radio glitch would cause directional changes of a more random nature. It sounds to me like the power system could be cutting out at brief, sporadic intervals due to the engine or ESC overheating or the power system drawing more current from the battery than the battery can deliver at a given instant. These kinds of problems would cause the motor to lose power for a brief time and result in the nose dropping.

If these nose dips occur at various speeds, my theory doesn't hold much water. If, on the other hand, the nose drops primarily only when you're flying at or near full throttle, this tends to confirm my theory.

To correct the issue, you might:

A) cut extra cooling holes at the rear of the cowl
B) upgrade your battery to one with a higher "C" rating or peak current capacity
C) upgrade your speed controller to one with a higher peak amp rating
D) try a different electric motor or two and see what kind of results you get

Good luck!

RE: RV-4 Dipping Problem
 

My CG I have changed with no effect on plane. I fly by mself at a small field near my house. Bigedmustafa I will do a check on speed affecting the plane. Thank you all for the info. Brian

RE: RV-4 Dipping Problem
 

Could weak batteries in my transmitter affect signal ? I'm using AA alkalines and have about 2 hours flight time on them. Plane started having the problem the last 3 times flying.

RE: RV-4 Dipping Problem
 

Yes, weak transmitter strength could cause your throttle speed to vary as well as other control problems. You should try fresh batteries before doing any additional troubleshooting.

RE: RV-4 Dipping Problem
 

I thought that might affect control. Maybe I'll try rechargable batteries. Thanks again for the help. This site is awsome for a beginner.