8. This type of starter provides a high power output and gives rapid starting characteristics. It has a turbine that transmits power through a reduction gear to the engine. In this instance, the turbine is rotated by high pressure gases resulting from the combustion of iso-propyl-nitrate. This fuel is sprayed into a combustion chamber, which forms part of the starter, where it is electrically ignited by a high- energy ignition system. A pump supplies the fuel to the combustion chamber from a storage tank and an air pump scavenges the starter combustion chamber of fumes before each start. Operation of the fuel and air pumps, ignition systems, and cycle cancellation, is electrically controlled by relays and time switches. An iso-propyl-nitrate starting system is shown in fig.11-5.