sudden throttle surge

I have an E- flite Air tractor electric , plug n play : my receiver- no AS3X. I have had the plane [ in flight ] suddenly surge full speed without my touching the throttle gimble ...on three successive flights. Last week while we doing a range test , the motor suddenly surged full speed while I was carrying it. My assistant yelled that he did not touch the throttle gimble. Is this a brownout, faulty BESC, We re binded the receiver before the range test . All channels were functioning. HELP.
 

Merv

Site Moderator
Staff member
Sounds like you are losing signal from the Tx.

After a flight, on the ground, make sure the plane is held down and everything is away from the prop. Then turn off the Tx to see if the motor goes to full throttle. If so you have a connection problem AND you fail safe is not setup correctly. When the Rx loses a signal it should cut the throttle to zero, not go full throttle.

Sometimes a damaged antenna or an antenna that is not installed correctly can cause this issue.
 

randyrls

Randy
Sounds like you are losing signal from the Tx.

After a flight, on the ground, make sure the plane is held down and everything is away from the prop.

OP: On further thought, I would remove the prop. Spinning props make me and my fingers nervous!! Especially if it happens without warning!
 

Hai-Lee

Old and Bold RC PILOT
A poorly set failsafe is the most likely cause as others have pointed out. Sadly there is more than one version of failsafe on Spektrum receivers and not all versions are supported on every receiver. Find out what the receiver can do and select what version you are going to set and then follow the correct bind procedure to ensure that the selected failsafe is actually programmed.

Much fear around inadvertent motor start due to failsafe not working is actually caused by faulty or wrong bind procedure.

I use a smartsafe and have for almost 4 years now and the only time my motors start is when the transmitter is powered up.

Have fun!