Incident Overview
A flight instructor reported that after three unsuccessful attempts to start the engine, he observed what he described as "steam" or "smoke" emanating from the carbureted engine compartment. He then initiated a fourth engine start, cranking the engine for approximately 15 seconds before stopping and exiting the airplane to inspect the engine compartment.
Fire Discovery and Response
Upon inspection, the instructor noticed a small flame in the engine compartment. He immediately ordered the student to exit the airplane. No fire extinguisher was available on the scene, and the airplane was quickly consumed by the fire.
Cause Determination
Investigators were unable to determine an ignition source for the fire.