Pressurisation Flashcards
What is the function of the pressurisation system?
To achieve and control automatic cockpit pressurisation
What happens when the aircraft passes 8,000 feet?
A series of sensors, regulators and valves located on the aft bulkhead, use P3 air from the ECS to provide positive pressure within the cockpit by controlling the release of excess pressure
How is the canopy sealed to provide a positive pressure within the cockpit?
P3 bleed air
What monitors the difference between internal cockpit pressure and atmospheric pressure?
Delta P regulator
Delta P is regulated to give a cockpit altitude of ____ ft
8000
What triggers a CKPT PX caption?
If the Delta P exceeds 3.9/4.0 PSI
What are the three settings of the PRESSURIZATION switch?
- NORMAL (guarded): the system operates automatically to pressurise the cockpit when passing through 8,000 ft
- DUMP: power is removed from the Dump solenoid, which opens electronically and mech opens the control valve to release cockpit pressure. However P3 air is still entering the cockpit via the inflow valve
- RAM/DUMP: both control valve and fresh air valve open, while the defog valve is over-ridden closed. This reduces P3 flow into the cockpit and allows fresh air to enter the cockpit and vent any fumes. P3 air is still flowing via the inflow valve