Page 269 - The Jet Engine

Maintenance

or restraining devices are also used. Adequate fire are switched or selected off; warning and emergency
fighting equipment must be readily available and systems are checked when applicable. Finally, after
local fire regulations must be strictly enforced. ensuring that the low pressure fuel supply is selected
on, the starting cycle is initiated.
35. Before an engine is started, the air intake and
jet pipe must be inspected to ensure that they are 37. At a predetermined point during the starting
free from any debris or obstruction. Each operator cycle, the high pressure fuel shut-off valve (cock) is
will detail his individual pre-start inspection require- opened to allow fuel to pass to the fuel spray
ments; a typical example of this for a multi-engined nozzles, this point varying with aircraft and engine
aircraft is shown in fig. 24-8. type; on some installations the shut-off valve may be
opened before the starting cycle is initiated. During
36. The starting drill varies between different the engine light-up period and subsequent accelera-
aircraft types and a starting check procedure is tion to idling speed, the engine exhaust gas
normally used. Generally, all non-essential systems temperature must be carefully monitored to ensure

Fig. 24-8 A pre-start inspection sequence.

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