Originally Posted by Fig Newton
I have to agree with Eflightray and David Hipperson here. Coming from an internal combustion background, you simply DO NOT put your fingers in the path of the prop. In my opinion and what I am reading on various forums, starting in the hobby with electric powered planes it seems that people tend to get a different complacency about the engine and yet it can and will bite, sometimes with serious results. Expecting the transmitter or even the speed controller to keep you safe is a gamble at best. When the battery is connected you should treat your engine like it is running. That's where coming from a gas background makes this easier to do.
The difference here is that an IC engine doesn't start if you happen to bump the throttle stick. It's not just about fingers, you can be behind the plane doing a control check and bump the throttle and have it takeoff, same with an IC engine, having and "off" switch can increase safety by one more level. It's a common feature with electric helicopters and the DX6i supports that feature in heli mode so why not in ACRO too? It is supported in the DX8 and I use it for my few electric planes.
Having a feature doesn't mean you have to use it, but not having it means you can't.