Aircraft Systems and Aerodynamics Flashcards
7 cards from real CPL practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Aircraft Systems and Aerodynamics flashcards as text
What is the primary purpose of a fuel injector in a reciprocating aircraft engine compared to a carburetor?
Answer: It delivers fuel directly to each cylinder intake port, eliminating carburetor icing
Fuel injection delivers fuel directly to each cylinder's intake port, eliminating the venturi and float chamber that make carburetors susceptible to icing.
In a hydraulic system, what is the function of an accumulator?
Answer: To store pressurized fluid and dampen pressure surges
An accumulator stores pressurized hydraulic fluid and absorbs pressure surges, providing a reserve of pressure when demand exceeds pump output.
Which type of drag increases as airspeed decreases during slow flight?
Answer: Induced drag
Induced drag increases as airspeed decreases because the wing must operate at a higher angle of attack to generate the required lift, strengthening wingtip vortices.
What happens to the manifold pressure of a naturally aspirated engine as altitude increases (throttle fixed)?
Answer: It decreases as ambient air density and pressure drop
With a fixed throttle, manifold pressure decreases with altitude because the ambient air pressure supplying the intake is lower, reducing the pressure available to the engine.
What is 'Mach tuck' as it applies to high-speed aircraft?
Answer: A nose-down pitching moment caused by aft movement of the center of pressure at high Mach numbers
Mach tuck is a nose-down pitching tendency that occurs as the aircraft approaches its critical Mach number, caused by the aft shift of the center of pressure as the shock wave forms.
In a multi-engine aircraft with asymmetric thrust, what is the 'critical engine'?
Answer: The engine whose failure creates the greatest adverse yaw and handling difficulty
The critical engine is the one whose failure produces the worst handling characteristics; on conventional US-configured twins with clockwise-rotating props, this is typically the left engine.
What is the purpose of 'intercoolers' in turbocharged aircraft engines?
Answer: To reduce the temperature of compressed intake air after it exits the turbocharger
Intercoolers lower the temperature of air compressed by the turbocharger, increasing its density before it enters the engine, improving efficiency and reducing the risk of detonation.