Motor runs after transmitter shut off (help please)

[sestudent09]

Hi, I just registered on this forum. I'm part of a group of high school students working on a project. We're trying to create a "Coanda saucer" by ourselves, but we're all first-time RC users.

The problem we're having is that after we throttle down, the motor does stop running, but 3-4 seconds after turning off the transmitter the motor turns back on again and goes full-throttle 0_0 The only way we've found to stop this is to disconnect the battery pack from the ESC.

Here's the equipment we're using:
Spektrum DX6 w/AR6000 receiver
ElectriFly SS-25 ESC 5V/2A
ElectriFly LiPo batteries (1500mAh 11.1V)
Axi 2808/24 Brushless motor

We don't have any servos connected because we're simply trying to achieve vertical lift, I don't know if that's relevant.

Any ideas on what we're doing wrong/ how to fix it? Thanks :D

[d_wheel]

Firstly, you should get into the habit of ALWAYS turning the transmitter on before turning the receiver on. When shutting down, ALWAYS turn the receiver off (disconnect batteries if you don't have a switch) first and then the transmitter.

To cure your problem, rebind the transmitter/receiver with the throttle in the idle position. This will reset your throttle failsafe to idle.

Later;

D.W.

[Sgt_Ric]

@ sestudent09 ...You are expecting the motor to be controlled by WHAT? when you have just turned off the very instrument used to control it!

Even if your radio doesn't have a failsafe feature, once the tranmitter is turned off (why I can't imagine) then the R/X is sibject to all kinds of RF goblins vying for control of your craft.

It sorta like jumping overboard a boat and expecting it to sail on without you.

d_wheel already mentioned resetting the radio's failsafe setting, but your ESC may also have it's own failsafe feature as some do.

[Sgt_Ric]

By the way... I hope you have fun with the Coanda saucer project.

I worked on building one 2 years ago and gave up fighting the lack of stablility.
It forced me to realize that installing the weight low (batteries, radio) and relying on the pendulum effect to self steady the craft was not going to work.

If ever I got the gyros trimmed to allow it to rise out of ground-effect, it would immediately roll over and crash... and since it was built using paper thin depron, it did not survive crashes well!

Good luck!

[rich smith]

Highly incompetent to shut off TX before plane.

[Gary Mortimer]

Well be fair, they are new at the game.

It should serve as a lesson to always treat propellers as live though!!!

Big ones or small.

Register at http://www.modelflying.co.uk its the site for RCME, a UK model flying mag, they have lots of beginners articles online.

I'm sure there are US examples.

Good luck.

Have fun