Incident
On Saturday, August 13, 2005, at 11:45 local time, a pilot attempted to hand-start a Cessna FR172G (registration D-ECHM) at Cuatro Vientos Airport in Madrid. The pilot had borrowed the aircraft from an acquaintance to fly to Málaga. Upon arrival, he filed a flight plan and found the battery dead; the master switch had been left on. Unable to obtain auxiliary power, he decided to start the engine by manually turning the propeller. After approximately 30 minutes of unsuccessful attempts, he advanced the throttle beyond the normal idle position. The engine then started, and the aircraft began to move slowly. The pilot tried to reach the cockpit but could not open the door. The D-ECHM continued moving until it struck a parked Cessna 172N (registration EC-HAT) that was ahead and to the left. The parked aircraft stopped the moving one, allowing the pilot to reach it and shut down the engine. The pilot was not injured.
Aircraft Information
The moving aircraft, D-ECHM, was a Cessna FR172G built in 1970, with a German registration. Its last annual inspection was on November 26, 2004, and the airworthiness certificate was valid until November 30, 2005. The owner's flight manual was incomplete; no specific procedure or prohibition regarding hand-starting was found. The manufacturer stated that their manuals do not include information on hand-starting. The parked aircraft, EC-HAT, was a Cessna 172N operated by American Flyers.
Pilot Information
The pilot held a valid private pilot license and a Class 2 medical certificate. He had 200 total flight hours, with 50 hours on the Cessna 172 type. He had performed hand starts previously, but only with wheel chocks in place. He learned the technique when purchasing an aircraft in Belgium, though he had no formal training in hand-start procedures.
Damage
Both aircraft sustained substantial damage. The stationary EC-HAT was worse affected: its right aileron and half of the right wing were struck by the propeller of D-ECHM. The right flap was deformed by the left wing strut of D-ECHM. The vertical stabilizer had abrasions and deformations from the left wing tip of D-ECHM. The propeller of D-ECHM, made of wood, was reduced to one-third of its original length. The windshield impacted the right wing of EC-HAT, and part of it fell into the D-ECHM cockpit. The left wing tip of D-ECHM separated upon impact with the vertical stabilizer.
Impact Angle
According to the pilot, the D-ECHM struck the EC-HAT at a very shallow angle between their longitudinal axes. After the propeller hit the right wing, the aircraft turned slightly left.
Probable Cause
The investigation concluded that the probable cause of the accident was the pilot's attempt to perform a hand start without following appropriate safety precautions.