use the object collision command (under "basic3d" in help) to determine when it's hit, then just have a variable that changes state when you detect a collision. When the variable has a new value, turn the object until it points in a certain direction, then move it until it reaches a certain point, then delete it (and create the obligatory explosion effect). Just read the names of commands in the help system, and check any that look promising.
System Specs: AMD Athlon 1700+ XP, GA-7VRX motherboard, 128MB DDR RAM, GeForce2 MX400 64MB VRAM