Rudder servo got burned out under no load or signal input from TX,whereas Elevator servo was working fine,Could any one suggest how to prevent burn out.

Did you use same kind of servo's for both elevator and rudder?If not some of them have a greater voltage stability while the others don't. Otherwise, the only suspection  is a 'short' in the circuit board.

 Emax 9gm Metallic gear servo was deployed in rudder.

Quote from: prabu85 on June 10, 2017, 11:33:05 AM
Emax 9gm Metallic gear servo was deployed in rudder.

It's clear from above that it's overvoltage problem. Keeping the voltage below 5.5V can ensure a good stability and avoid burns for small analog servo's.

If all else for eg voltage is ok, just don't use avionic crap.
A friend's servos on brand new stealth got screwed mid flight in maiden.
All groun tests were ok.
Servos simply failed.

Thanks for sharing this information.

Can you open the case and post pics of the PCB ? Is the internal DC motor intact ?

Same story with my avionic servos...2 of them got destroyed under no load.,.

sad to note

This is surprising, and not good. Have you taken this up with RCB? Please do, they may well need to take some corrective action

Incidentally, which RX battery were you using? Or is it an electric and powered through a BEC

Quote from: sanjayrai55 on January 11, 2018, 10:45:06 AM
This is surprising, and not good. Have you taken this up with RCB? Please do, they may well need to take some corrective action

Incidentally, which RX battery were you using? Or is it an electric and powered through a BEC

yes you should contact RCB