Cartridge starter

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A cartridge starter is a device which by means of a pyrotechnical propellant charge for energy cranking of internal combustion engines and gas turbines supplies (see also: Coffman starter ).

As a gas producer, are special before launching into the cartridge chamber of the starter to be loaded cartridges used, the one inside as solid rocket motor are built. Propellant substances such as cordite are used as fuel . These cartridges are mostly ignited electrically, less often by firing pins . The cartridge burns down very quickly (two to five seconds), but can release a very high drive power during this time. The working gas that arises when it burns down is used to crank the engine in different ways, depending on the design: The gas usually drives a small starting turbine, which turns the crankshaft or the turbine shaft of the engine to be started by means of a reduction gear and overrunning clutch. The gas can also act on a rack and pinion via a piston. It is also possible to direct the working gas directly onto the turbine blades of a jet engine or directly onto the engine piston of a reciprocating engine.

The system is mainly used in military aircraft. A major advantage is that, thanks to the quickly replaceable cartridges, no powerful batteries or ground start devices are required on board . Thanks to the self-sufficient starting process, a large number of aircraft without large ground infrastructure could start their engines at the same time in the event of an alarm start.

Cartridge starters were also installed in early tractors , such as the single-cylinder Field Marshall from Marshall, Sons & Co. (England).

Cartridge starters are rarely used today, since the explosives used present a considerable risk of explosion if the cartridge is damaged and alternative methods (e.g. powerful auxiliary power units) are available nowadays . The cartridges are sensitive to impact and age very quickly. Larger cartridges (for starting the engine in Ghost48 engines) contained up to 700 g of cordite.

Not to be confused with cartridge starters are so-called Zündlunten or primers (trade name "Zündfix" ), which in older, mostly single-cylinder diesel stationary engines or tractors, were screwed into the combustion chamber of the cylinder using a bracket before the engine was started. These had the task of providing an auxiliary ignition source for the fuel for the first ignitions after starting when the engine was cold, as these engines usually had no electrical system and therefore no pre-glow system.

Web links

Individual evidence

  1. Riding shotgun should have been starting shotgun , report on about the Field Marshall tractor , English language, accessed June 25, 2016