081.03 Stall, Mach tuck, and upset prevention and recovery Flashcards
Define ‘VS’. It is (lower/higher) than VS1g.
Minimum calibrated airspeed at which an aeroplane remains controllable, but does not require horizontal flight. Therefore it is lower than VS1g.
Define ‘VS1’.
Stall speed or the minimum steady flight speed for a specified configuration (which may be clean configuration)
Define ‘VS0’.
Stall speed for landing configuration
Define ‘VSR’.
Reference stall speed. Usually equal to VS1g.
Define ‘VS1g’.
Minimum calibrated airspeed at which an aeroplane is able to maintain steady horizontal flight (L=W)
Stall speed VS1g is determined with the CG as far (forward/backward) as possible.
Stall speed VS1g is determined with the CG as far (forward) as possible.
Behind the transition point in a boundary layer, the mean speed (increases/decreases) and the friction drag (increases/decreases).
Behind the transition point in a boundary layer, the mean speed (increases) and the friction drag (increases).
Compared to the laminar boundary layer, a turbulent boundary layer:
- is (thicker/thinner)
- gives a (lower/higher) skin friction
- has (more/less) kinetic energy
- will seperate (more/less) easily
Compared to the laminar boundary layer, a turbulent boundary layer:
- is (thicker)
- gives a (higher) skin friction
- has (more) kinetic energy
- will seperate (less) easily
Stall speed (IAS) (remains constant/increases/decreases) at lower altitudes but (remains constant/increases/decreases) at higher altitudes due to compressibiltiy effects.
Stall speed (IAS) (remains constant) at lower altitudes but (increases) at higher altitudes due to compressibiltiy effects.
- EAS remains contstant until supersonic -
Centre of pressure moves (forward/aft) on a swept back wing as angle of attack approaches and exceeds the critical AoA.
Centre of pressure moves (forward) on a swept back wing as angle of attack approaches and exceeds the critical AoA.
Centre of pressure moves (forward/aft) on a straight wing as angle of attack approaches and exceeds the critical AoA.
Centre of pressure moves (aft) on a straight wing as angle of attack approaches and exceeds the critical AoA.
Minimum control speeds are determined with the CG at the (forward/aft) limit.
Minimum control speeds are determined with the CG at the (aft) limit.
Type of stall that has the largest associated AoA is (accelerated/high speed/low speed/deep) stall.
Type of stall that has the largest associated AoA is (deep) stall.
The main purpose of a boundary layer fence on a swept wing is to improve (high/low) speed handling characteristics.
The main purpose of a boundary layer fence on a swept wing is to improve (low) speed handling characteristics.
(Stall speed/αcrit) remains unchanged regardless of gross weight.
(αcrit) remains unchanged regardless of gross weight.
Describe ‘deterrent buffet’ and why it can be considered a stall limit.
A buffet so strong that any pilot will feel he needs to leave these buffet conditions. It can be considered a stall limit because the buffet is so strong that pulling any further will cause the aircraft to enter an actual stall.
New LO. Source: https://safetyfirst.airbus.com/app/themes/mh_newsdesk/pdf/safety_first_21.pdf
State in how the following will change the buffet free range change. Change in:
- Increase in altitude
- Increase in speed
- Increase in mass
- Increase in load factor
- Push-/pull-over manouvre
State in which of the following changes will the buffet free range change. Change in:
- Increase in altitude → buffet free range decreases
- Increase in speed → no change
- Increase in mass → buffet free range decreases
- Increase in load factor → buffet free range decreases
- Push-/pull-over manouvre → buffet free range increases (load factor < 1)
A stall can occur at any airspeed, attitude or altitude because (…).
A stall can occur at any airspeed, attitude or altitude because (stall solely depends on angle of attack).
