Problem with Carlgoldberg Yak 77"

[best_panther]

Hi Everyone

I'm new in this kind of planes and I have this problem with my Yak 77", with the Knife-edge flight.

Fist of all I will put all of the configuration:

Engine: DA-50
prop: 23x8 NX
Radio: Spektrum DX7
Servos 2 ailerons (1 per wing), 2 for elevator, 1 for rudder, all Hitec 5645MG, and 1 standar for throtle
Batteries, 1 4.8 V 1500 mah Ignition, and 1 6v 2700 mah for receiver and servos.

Mods:
I put the tank under the wing tube so the Center of Gravity doesn't affect the flight
I put the rudder servo in the back (next to elevator servors, Carl golberg already put Window for servor if user like) so I can get a tailheavy plane.

The problem is

When I try to put the plane in knife-edge flight, when I apply rudder to maintain the plane straight, suddenly and inmediatly the plane turns very fast (I turns to it's first position, "normal flight", As a reference this always happens in a Trainer plane when you try to make a knife-edge flight) , And I don't know what to do.

I quit some rudder travel, to see if it was too much throw, but the plane has the same reaction.

So what can I do? or anybody had the same problem with this plane or another plane?




Thanks.
Best Regards
Richard

[kmrbrown]

I will try to help
if I understand right when you bank the plane on its side and add rudder the plane
trys to right it self. somewhat normal.
now use ailerons to hold it sideways and elevator to track straight

[ilovemetro]

	Quote: Originally Posted by kmrbrown
	I will try to help if I understand right when you bank the plane on its side and add rudder the plane trys to right it self. somewhat normal. now use ailerons to hold it sideways and elevator to track straight

Simply using aileron inputs isn't the way to fix it.

Can you show us pics?

[Propstriker]

1 HS 5645 on the rudder?

[zumaboster]

Hi,
With most Yaks, being too tail heavy will cause awesome harriers and hovers but bad knife edge. My GP 81" yak 54 needs quite a bit of aileron and elevator to hold a nice knife edge. Try moving the CG forward. It is also easier to knife edge at higher speeds. Try screaming across at full throttle and just roll onto your most comfortable side. Without any rudder see what it does, then try to add a slight bit of rudder to feel which way it wants to go. It could just be a case of too slow with too much input.