pneumatic, pressurisation systems

#25. Safety valves are biased:

• Ainwards.
• Boutwards.
• Cin the direction sensed by the SVC.
• Dneither a nor b.

#1. Main and nose wheel bays are:

• Apressurised.
• Bunpressurised.
• Cconditioned.
• Ddifferent, with the mains being unpressurised and the nose pressurised.

#2. Normal maximum negative differential pressure is:

• Awhen atmospheric pressure exceeds cabin pressure by the amount permitted by the system controls.
• Bwhere the cabin pressure falls below aircraft altitude pressure at which time the inward relief valve opens.
• Cwhen the cabin pressure exceeds the atmospheric pressure by 0.5 PSI.
• Dthe pressure at which the duct relief valve is set to operate.