RC India

RC Models => Gas/Glow/Nitro Planes => Topic started by: mickey on November 24, 2011, 01:45:50 PM



Title: Help needed in tuning seagull boomerang
Post by: mickey on November 24, 2011, 01:45:50 PM
Hi ALL
I bought seagull boomerang from Mr. Kalsi through a friend.
He helped me to assemble the model.

I am using Futaba 6J TX.
I m using OS .46 AX and MasterAirscrew 11x6 prop (G3 series) trimmed slightly to avoid sharp edges.
Balanced the plane slightly nose down.

During my maiden flight take off went well.
When the throttle increased to 75% and elevator kept in neutral the plane went to nose up position and went out of control.
Also with 50% throttle when slight up elevator movement is given the plane went to nose up position and went out of control.

We have set the throws as recommended in seagull boomerangs manual.
We have also tried dual rate and expo to reduce the sensitivity of the controls. But no hope.
The same scenario happens again.

How to overcome this problem?
Is the power of the engine too high?
Should i need to change propeller(Then what size)?

Please help.



Title: Re: Help needed in tuning seagull boomerang
Post by: rcpilotacro on November 24, 2011, 02:05:56 PM
Thrust line & CG these also could be culprits , please check them too


Title: Re: Help needed in tuning seagull boomerang
Post by: puneet on November 24, 2011, 07:13:35 PM
you are using the right combination of engine and prop for your plane.

check CG before investigating further.

cheers


Title: Re: Help needed in tuning seagull boomerang
Post by: msri21 on November 25, 2011, 08:09:37 AM
Hi, check the engin mounting angle. If it is not correct add one or two washer behind engin mount to get it correct . Engin has to be pointing down and left slightly. I do not remember the angle.


Title: Re: Help needed in tuning seagull boomerang
Post by: saikat on November 25, 2011, 08:31:06 AM
It sounds that you(or your friend) have made more than one flight and were
able to get it down safely.

Not too bad.
Put some weight in the nose and things will improve.



Title: Re: Help needed in tuning seagull boomerang
Post by: xxkrishxx on November 25, 2011, 08:40:11 AM
hi buddy i'm using OS 46AX engine n Master AirScrew 11x6 prop..have done many flights without any issues..by the way where r u flying? Will join with u from Jan2012 as i'm relocating to Tamil Nadu..


Title: Re: Help needed in tuning seagull boomerang
Post by: mickey on November 26, 2011, 01:18:03 PM
hi buddy i'm using OS 46AX engine n Master AirScrew 11x6 prop..have done many flights without any issues..by the way where r u flying? Will join with u from Jan2012 as i'm relocating to Tamil Nadu..

We are flying at annur field.


Title: Re: Help needed in tuning seagull boomerang
Post by: mickey on November 26, 2011, 01:22:31 PM
Hi guys,

Thanks for the info.

I will make changes to thrust line, cg, also add some nose weight (IF NECESSARY) and give it a try this weekend and make an update.


Title: Re: Help needed in tuning seagull boomerang
Post by: anwar on November 26, 2011, 11:42:54 PM
Engin has to be pointing down and left slightly. I do not remember the angle.

Down and RIGHT for tractor prop setups, when looking from the tail of the plane to the nose.


Title: Re: Help needed in tuning seagull boomerang
Post by: mickey on December 20, 2011, 09:56:11 PM
Hi Guys,

The problem has been sorted out.
Actually the rubber band that came with the kit is not of good quality and its not stiff when used with the plane.
At particular position while flying the angle of attach increased as a result of main wing lift from the fueselage(Because the rubber band is not stiff).

I have tried cycle vol tube and it worked out well.