RE: ESC poltergeist?
To safely and completely remove power to an electric aircraft, you need to interrupt the connection between the battery and the ESC. Whatever device you use to make and break that connection must carry the full current of the power system. For today's high powered systems, a switch would have to be a pretty large one, plus it introduces another failure point and more weight.
A few ESCs do have a switch, but its only function is to isolate the ESC from the receiver. It does not cut off power to the ESC, so it does not positively prevent inadvertent motor start-up. The safety and effectiveness of ESC switches has been debated a great deal. [link=http://www.rcgroups.com/forums/showthread.php?t=446961]Click here for one thread on the topic.[/link]
In addition, the ESC still draws a small amount of power even when its switch is "off." Over time, it will drain the battery if you leave it connected. Many folks have ruined lipos by leaving them connected to ESCs that are "off." Of course, for safety reasons, you should not leave lipos in a plane after flying anyway, and you definitely should not charge a lipo that is buried in a plane!
Some folks use a heavy-duty harness inline with a battery lead that requires plugging in a heavy-duty jumper (often made from a Deans Ultra plug) to complete the circuit. The plug is located such that it is accessible from outside the plane.
- Jeff