DCS AERGES MIRAGE F1, Руководство по эксплуатации самолета

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DCS: Mirage F1 Flight Manual Version 1.0
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3.4 JET ENGINE
Introduction
The Mirage F1 is powered by the SNECMA ATAR 9K-50 afterburning turbojet. This engine is the
pinnacle of the evolution of the ATAR family, started in the late 1940s by SNECMA with former
BMW engineers for the Vautour and Mystère aircraft.
The engine is located in the rear part of the aircraft, with the air intakes behind and on the sides
of the cockpit. Static and at sea level, it is capable of delivering 50 kN of thrust in military power
settings and up to 70 kN in afterburner mode. It can operate at speeds in excess of Mach 2.1.
Description
The engine has 9 stages in the compressor and 2 stages in the turbine. It also counts with a
convergent-divergent adjustable nozzle. Supplementary valves open at the sides of the aircraft
to increase airflow at low airspeeds and high thrust settings. Supersonic shock-cones also move
to adjust the airflow at supersonic speeds and prevent the ingestion of shock waves.
In idle, the engine spins at 2900 RPM, in full power at 8400 RPM. At speeds above M 1.4, the
maximum RPM is increased to 8900 and the engine enters a mode called ‘overspeed’. Changes
to throttle input in ‘overspeed’ will result in an engine stall or flameout, so speed has to be
reduced by airbrakes, manoeuvring or ascending in that situation.
Lubrication is provided by an oil deposit of 9 litres (an emergency oil deposit of 3.5 litres is also
available). Consumption of oil limits the autonomy of the aircraft to 6 hours. In case of failure of
the throttle or main oil system, an emergency regulation mode exists, in which the emergency
oil deposit is used and engine power is adjusted by pulses.
The start-up of the engine occurs sequentially, with an electric motor starting a gas generator,
which, in turn, starts the engine. The starter pushbutton shouldn't be pressed for more than 2
seconds to avoid damaging the electric starter and should never be pushed when the engine is
turning, at the risk of destroying the starter system.
A fuel dipper mechanism prevents engine stall from ingesting the exhaust fumes of the missiles
or cannons. When a missile is fired, the fuel dipper reduces the amount of fuel sent to the
engine, causing a drop in RPM, turning off the AB and opening the nozzle for 3 seconds. In the
case of the cannons, only a reduction of RPM occurs.