Aerodynamics and Aircraft Systems Flashcards

Maneuvering speed (Va) is significant because below Va:

Answer: The aircraft will stall before exceeding its structural design load limit with full control deflection

Below Va, a single full control surface deflection will cause the aircraft to stall aerodynamically before the structural design limit load factor is reached, protecting the airframe.

VMO/MMO differs from VNE in that VMO/MMO:

Answer: Is the maximum operating limit for jet transports, not an absolute never-exceed speed like VNE

VMO (maximum operating IAS) and MMO (maximum operating Mach) are the red-line operating limits for transport category jets, with a design dive speed (VD/MD) providing an additional structural margin beyond them.

A forward center of gravity (CG) position, compared to an aft CG, results in:

Answer: Greater longitudinal stability and higher stall speed due to greater tail download required

A forward CG increases the nose-down pitching moment, requiring greater tail download for trim, which increases the effective weight the wing must support and raises stall speed while improving pitch stability.

Density altitude is defined as:

Answer: Pressure altitude corrected for non-standard temperature

Density altitude is the altitude in the International Standard Atmosphere that corresponds to the actual air density at a given location, computed from pressure altitude and temperature deviation from standard.

During a coordinated level turn at a constant bank angle, as airspeed decreases the required angle of attack:

Answer: Increases to maintain the increased load factor needed for level flight

In a level turn, the vertical component of lift must equal weight; as airspeed decreases, the angle of attack must increase to maintain sufficient total lift against the higher load factor imposed by the bank.

What is the primary structural concern when flap extension speeds (VFE) are exceeded?

Answer: Aerodynamic loads on the flap structure and wing attachment points exceeding design limits

Above VFE, the aerodynamic hinge moments and surface loads on extended flaps can exceed the structural design limits of the flap panels, tracks, and wing attachment fittings.

The Effect of an aft CG beyond the aft limit on aircraft handling is primarily:

Answer: Reduced longitudinal stability, possibly requiring continuous pilot input to prevent divergence

With CG behind the neutral point, the aircraft becomes longitudinally unstable — small pitch disturbances tend to diverge rather than self-correct, requiring active pilot or autopilot compensation.