The Learjet 35A sustained damage after being struck by a runway Aeropro Eurofox while parked at Jeffersonville-Clark Regional Airport, IN (JVY). The owner of Eurofox N829BM, with no intent to fly, placed a wooden chock under one of the main landing gear wheels and removed the upper engine cowl. He attempted to trouble shoot an engine starting problem on the Eurofox aircraft. The Eurofox engine started when his right knee contacted the starter switch as he attempted to enter the unoccupied aircraft. The Eurofox’s engine continued to run causing the aircraft to jump the wooden chock and surge forward. The unoccupied aircraft traveled approximately 200 feet until it struck a Learjet 35A, registration N376HA. The Eurofox’s right wing forward leading edge and wing tip struck the Learjet empennage tail section. The impact caused both the Learjet and the Eurofox to pivot in clockwise directions. The eurofox rotated to a position which permitted its composite propeller to disintegrate as it contacted the Learjet’s left outboard wing, aileron, and fuel tank. The Eurofox’s engine ceased operating shortly after contact with the other aircraft. The Eurofox suffered substantial damage to its entire wing structure, wing struts, propeller, forward fuselage, firewall, and engine compartment. The Learjet suffered substantial damage to the empennage tail section, wing structure, and fuselage. There was visible damage to the wing at the wing root and to the fuselage at areas above, below, forward, and aft of the wing root.