8. Basic aerodynamics - Q&A
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The ISA
- defines a standard atmosphere model.
- is referenced from the equator.
- is taken from 45 degrees latitude.
Why
On an aircraft with an all-moving tailplane, pitch up is caused by
- decreasing tailplane incidence.
- raising the tailplane incidence angle.
- increasing tailplane incidence.
please explain
Stall commencing at the root is preferred because
- it provides the pilot with a warning of complete loss of lift.
- it provides a clear aerodynamic warning of the approaching loss of aileron effectiveness.
- it will cause the aircraft to pitch nose up before the outer wing sections lose their lift.
Stall commencing at the root is preferred because it provides the clear aerodynamic warning of the approaching loss of aileron effectiveness .Warning signs: When the wing root stalls first, the disrupted and turbulent airflow causes buffeting or a shaking of the aircraft's elevators and control stick, alerting the pilot to the impending stall before total lift is lost .Control retention: Because the stall starts inboard, the wingtips continue to fly smoothly. Since ailerons are typically located on the outer portions of the wing, the pilot maintains roll control to keep the wings level and safely recover
What effect does lowering flaps for takeoff have?
- Reduces takeoff speeds only.
- Reduces the landing speed only.
- Reduces both takeoff and landing speeds.
why not C?
What produces the most lift at low speeds?
- High camber ratio.
- Low aspect ratio.
- High aspect ratio.
High Camber Ratio: (Produces the most lift) The increased curvature accelerates air over the top of the wing more effectively, creating a massive pressure difference to generate lift even during slow flights or take offs .High Aspect Ratio: While highly efficient at cruise and reducing drag, they do not inherently boost maximum lift at low speeds compared to a cambered wing.
On a swept wing aircraft if both wing tip sections lose lift simultaneously the aircraft will
- yaw uncontrollably.
- pitch nose up.
- pitch nose down.
What is the reason it is nose up?
The ISA
- defines a standard atmosphere model.
- is referenced from the equator.
- is taken from 45 degrees latitude.
can someone explain?
A flying control mass balance weight
- keeps the control surface C of G as close to the trailing edge as possible.
- tends to move the control surface C of G close to the hinge line.
- tends to move the control surface C of G forward of the hinge line.
why? shouldn't be C?
The power required at low altitude for a given IAS is
- unchanged with altitude.
- higher.
- lower.
How is that possible? The air is more dense, therefore the drag is increased, thus the thrust (power) should be increased
The vertical fin of a single engined aircraft is
- parallel with both the longitudinal axis and vertical axis.
- parallel with the longitudinal axis but not the vertical axis.
- parallel with the vertical axis but not the longitudinal axis.
Can someone explain?
Longitudinal dihedral (decalage) is:
- The angle of sweepback between the wing leading edge and a line perpendicular to the fuselage centreline
- The upward angle of the wings relative to the horizontal, which provides lateral roll stability in a sideslip
- The difference in angle of incidence between the wing and the tailplane — it contributes to longitudinal stability
Please explain. Thank you
Under what conditions will an aircraft create best lift?
- Hot damp day at 1200 ft.
- Cold dry day at 200 ft.
- Cold wet day at 1200 ft.
why not the first
Power-off stall versus power-on stall:
- Power-on stalling speed is higher because the propeller slipstream increases the effective airspeed over the wing
- Power-on stalling speed is lower because the vertical component of thrust helps support the aircraft weight, reducing the lift requirement
- Power setting has no aerodynamic effect on the stalling speed regardless of engine type or thrust line orientation
How can that be true? Thrust is a horizontal component acting parallel to the aircraft’s line of direction.
With an increase in the amount of flap deployment, the stalling angle of a wing
- remains the same.
- increases.
- decreases.
Can Someone explane me why?
With an increase in the amount of flap deployment, the stalling angle of a wing
- remains the same.
- increases.
- decreases.
Can Someone axplane me why?
Stall commencing at the root is preferred because
- it provides the pilot with a warning of complete loss of lift.
- it provides a clear aerodynamic warning of the approaching loss of aileron effectiveness.
- it will cause the aircraft to pitch nose up before the outer wing sections lose their lift.
It’s wrong right?
During flight, an aircraft is yawing to the right. The aircraft would have a tendency to fly
- right wing low.
- left wing low.
- nose up attitude.
fake?
Extending a leading edge slat will have what effect on the angle of attack of a wing?
- Increase the angle of attack.
- Decrease the angle of attack.
- No effect on angle of attack.
The effect of the slat is to prolong the lift curve by delaying the
stall until a higher angle of attack. how does it possible that the angle of attack decreases?
Air above Mach 0.7 is
- partially compressible.
- incompressible.
- compressible.
Air should not be take compressible Above Mach 1?
Someone can explain me? Thanks
As altitude increases, pressure
- decreases exponentially.
- reduces at a constant rate.
- rises exponentially.
Isn't:-1hPa in 27ft. So why it decreases exponentially?
Mach trim operates
- along the longitudinal axis.
- along the lateral axis.
- to reduce Dutch roll.
It´s correct?
An engine which produces an efflux of high speed will be
- less efficient.
- more efficient.
- unaffected by efflux speed.
Hi, what is high speed efflux?
Thanks
Sweepback increases Mcrit by
- decreasing the amount of airflow over the lowest point on the aerofoil section.
- decreasing the amount of airflow over the highest point on the aerofoil section.
- increasing the amount of airflow over the highest point on the aerofoil section.
Please write your question here.
Angle of attack on a down going wing in a roll
- increases.
- decreases.
- unaffected.
,,
The trailing vortex on a pointed wing (taper ratio = 0) is
- at the tip.
- distributed evenly along the span.
- at the root.
any help ? why is like this