Packs

PACKS

The aircraft pressurization is mainly performed by two PACKs, using the engine bleed air. Each PACK has its own controller, which controls the PACK inlet valve, and the Hot Air by pass valve.

PACK Controller

Mixer Unit

Ram Air Input

Each PACK is a hot/cold air turbine system that uses the energy of the hot air to turn a turbine to expand the air and thus cool it. Two heat exchanges are located either end of the turbine and they are fed with out side air to perform the heat exchange.

Each PACK is represented at the top of the Bleed system display . The PACK display shows the Inlet flow rate selected (Low, Normal or High), the Turbine and compressor air temperatures and the temperature selected (Hot or Cold)

The aircraft’s pressurization system is display ed on t he Bleed system display. The Display shows the Bleed inputs, the PACKs and the output status of the Mixer unit.

Heat Exchanger

Compressor unit