AIRPLANE ENGINE GLOW PLUG BY CHAMPION

This Champion glow plug was what I used in an airplane engine. It has a coiled resistive element that was connected to a 1.5 volt battery. The element would get red hot and allow the engine to start. Once started , the battery could be disconnected and the engine would continue to run. It still works.
Champion also manufactured spark plugs . Spark ignition engines were hard to start as the spark control had to be varied along with the carburetor setting. The system also needed a battery, high voltage coil and condenser , just like an auto ignition system, built into the airplane.