Today March 21st is certainly my lucky day. I have been planning to replace my receiver pack for about 2 weeks and wanted to wait for local hobyy store to get it. After my last flight today wen i was putting the plane away i noticed that my 7.4 730 mah cell pack had puffed. Again, i wanted to replace the pack becuase when fully charged it would only read 8.27 volts as opposed to the 8.39 that it would normally be. I always check before each flight with a load meter to make sure that they battery can take load that the servos need to operate properly. Long and short of it is check, double check and triple check your batteries, to make sure that they are still good. Lucky pilot signing off