Bi-copter+ KK215 home test

[Heli Lim]

[Super-Hornet]

Hi there
Sorry to say this, but it appears to be not that stable. I tried to create a bicopter using propeller as the lifting manner as well but it also suffers from instability.
U notice that, it easily goes into nose up/down or pitch up/down oscillation. It suffers from no stability in terms of pitch axis.

This is what I analyst between Osprey and Chinnok or Seaking.
For what I see it, in Osprey, the dual rotor is actually like an helicopter rotor (like in Chinnook or Seaking..that is it is actually a collective pitch..there is a swash plate inside).
The stability for the axis perpenticular between two rotor (In Osprey, it is pitch axis, in Chinook/Seaking, it is Aileron axis) is achieve using tilting the rotor blades
(or in other word change pitch like when u apply aileron/elevator to swash plate). This tilting rotor will create a force/torque to tilt the whole craft on the rotor mounted axis (again, just like normal single rotor heli).

Tilting motor+propellar do not provide any oppositing force to stabilize the craft. Thus, IMHO, using tilting rotor in bicopter will not able to achive/provide the required stability.

That mean, in order to create bicopter (either a Osprey or Avatar dragonfly), u really need a helicopter rotor head instead (either collective pitch or fixed pitch)...so long it has the swash plate to tilt the rotor disc instead.

[Super-Hornet]

Silly mistake.
Typo error: should be spelled as Chinook.
Wrong name: It should be Sea Knight..not Sea King.
http://upload.wikimedia.org/wikipedi...Helicopter.jpg