Incident Summary
The pilot reported that he could not start the engine and requested assistance. A battery cart was brought out, and the engine was jump started. While airborne, the pilot detected an odor resembling ether and decided to land the airplane. He stated that the smell intensified and the engine began running rough. While taxiing off the runway, he smelled raw fuel and observed smoke. After evacuating the airplane, he saw flames coming from the pilot's side of the engine (aft of the firewall) and the wing root area.
Aircraft Information
The aircraft had accumulated an estimated 18,000 hours of flight time. According to representatives from Piper and Gill (the battery manufacturer), the resistance of the aluminum battery cable increases with age, flight time, and flight cycles. The fuel lines and the battery cable are located 4 to 6 inches apart in the vicinity of the fuel selector, which is the same area where the pilot first observed the fire.
Manufacturer Statements
A Piper representative stated that 'a dead or depleted aircraft battery should not be charged in the aircraft.' This information was not available in the Pilot Operating Handbook (POH). Additionally, Service Bulletin #836A had not been performed, and the original aluminum battery cable had not been replaced by a copper battery cable.