Copter: Improve comments on thrust_loss_check()

Co-authored-by: Iampete1 <[email protected]>

ArduCopter/crash_check.cpp

@@ -96,7 +96,12 @@ void Copter::crash_check()
     }
 }
 
-// check for loss of thrust and trigger thrust boost in motors library
+// thrust_loss_check - returns true when the aircraft detects for 1 second that it is:
+//                      above 90% demanded thrust or high thrust saturation,,
+//                      less than 15 degrees lean angle target,
+//                      less than 30 degrees of attitude error,
+//                      is descending.
+// This check provides a warning that the aircraft is near it's maximum thrust limits and is used trigger thrust boost algorithm in the motors library
 void Copter::thrust_loss_check()
 {
     static uint16_t thrust_loss_counter;  // number of iterations vehicle may have been crashed