English to Russian Tech/Engineering Engineering (general) VHP engines

Exhaust purging - To prevent explosions and personal injury the engine and the exhaust system *are purged by cranking the engine* for several seconds before the ignition is turned on and the fuel valves are opened. The purge volume of the engine is approximately its displacement for every two revolutions. Additional purge time can be added in ESM via a user-programmable field. Up to 30 seconds can be added while still allowing the engine to start.
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