The question is, if you turn on your radio while someone else has the pin, are you responsible for their plane. Not are you responsible if the plane doesn't cost over $400 or are you only responsible if you do it on purpose or...... If you are at fault, you are responsible for the other persons property if you cause damage to it. As far as the replacement cost, that's between them and you. Most people are very reasonable if the person admits they made a mistake and are willing to try and fix it!!! Once again, if i see a jet flying i know that he's only going to fly for maybe 7 minutes. Instead of taking a chance, I'll just wait a couple of minutes until he's landed then I'll go ahead and fly. That's using a little common sense. If there's a Ferrari cruising down the road in front of me, I'm not going to tailgate it, I'm going to give it plenty of extra room because I know there's no way in **** that I can afford to ever replace it!! There's plenty of time for everyone to fly and enjoy their hobby!!!