CPL Aircraft Systems and Aerodynamics 3

Question 1

What is the aerodynamic effect of deploying leading-edge slats?

Accepted Answer

They increase wing camber and allow higher angles of attack before stall

Answer

Leading-edge slats increase wing camber and create a slot that energizes boundary layer airflow, allowing the wing to sustain lift at higher angles of attack and lower speeds.

Question 2

In a pressurized aircraft, what does 'differential pressure' refer to?

Accepted Answer

The difference between cabin pressure and outside ambient pressure

Answer

Differential pressure (delta-P) is the difference between the pressurized cabin pressure and the ambient outside air pressure, which determines structural loads on the fuselage.

Question 3

What is 'propeller slip' in aviation?

Accepted Answer

The difference between the theoretical pitch distance traveled and the actual distance advanced per revolution

Answer

Propeller slip is the difference between the geometric pitch (theoretical distance advanced per revolution) and the effective pitch (actual distance advanced), caused by the propeller working against air resistance.

Question 4

What is the relationship between aspect ratio and induced drag?

Accepted Answer

Higher aspect ratio produces less induced drag for the same lift

Answer

A higher aspect ratio wing generates less induced drag for the same lift coefficient because the wing tips are farther apart, reducing the strength and influence of wingtip vortices.

Question 5

During engine start, why is it critical to avoid 'hot starting' a turbine engine?

Accepted Answer

Excessive turbine inlet temperature during light-off can cause thermal damage to turbine blades

Answer

A hot start occurs when turbine inlet temperature exceeds limits during the start sequence, which can cause severe thermal damage to turbine blades and combustion components.

(CPL) Commercial Pilot Licence Practice Test

(CPL) Commercial Pilot Licence Practice Test

CPL Aircraft Systems and Aerodynamics 3