GeraldO is right, the AAA NIMH batteries will not handle a Speed480. As soon as the motor comes on the output of the battery pack will drop below 5V and the ESC will just shut it back off. Try some HE1100 NIMH cells http://www.aircraft-world.com , they will work well. Also AA NIMH cells will work fine, http://www.nimhbattery.com/mh-dba-1700tab.htm but are a bit heavier.