First off, I do applaud the idea you have. That's how things get invented in this country, by people thinking outside the box. However, I'm not trying to be a stick in the mud or anything like that. But I see these problems with your idea. First, many crashes are caused by a loss of radio signal to the plane. In this case you would not be able to "flip the switch" to deploy the chute. Now, as a solution. If you set the failsafe on the radio to kill the engine and deploy the chute this might work, as the plane would go to the chute if radio signal was lost.

Second, many more crashes happen just too darn fast to even think about flipping the switch. By the time you know you need to deploy the chute you simply aren't going to have time to use it.

Ken