NIFE AERO GAVYN EXAM
QUESTIONS WITH 100% CORRECT
ANSWERS
Describe boundary layer separation in regards to adverse pressure gradient - Answer-
Airflows from leading edge (high pressure) towards the point of max thickness (low
pressure) resulting in a favorable pressure gradient.
- This assists the boundary layer in adhering to the surface with high kinetic energy.
As the air flows from the point of max thickness (low pressure) to the trailing edge (high
pressure), it encounters a adverse pressure gradient. this impeded the flow of the
boundary layer.
Adverse pressure gradient is strongest when:
- high AoA
- high lift conditions
If the boundary layer does not have a sufficient amount of kinetic energy to counteract
the adverse pressure gradient, a stall occurs.
Define Stall - Answer-An increase in AoA results in a decrease in Cl.
EXPLAIN the difference between true and indicated stall speed - Answer-Min airspeed
required to maintain level flight occurs at ClMaxAoA. True uses density at current
altitude and stall speed will be affected by altitude. Indicated uses density on standard
day and will not be affected by altitude.
What is the equation for Stall speed and indicated stall speed - Answer-Vs = sqr rt
(2W/rho*s*Clmax)
IASs = sqr rt(2W/rhoknot*s*CLmax)
EXPLAIN the effects of gross weight, altitude, and flaps given the stall
speed equation - Answer-As weight increases, stall speed increases
As altitude increases, stall speed increases
As flaps are lowered, stall speed decreases
EXPLAIN the difference between speeds with respect to power on and
power off stalls - Answer-Power on stall = Lower Stall speed
Power off stall = higher stall speed
, Describe the relationship between the wings during a spin - Answer-During a spin, the
lower wing is more stalled and has a higher AoA than the higher wing which is less
stalled and at a lower AoA.
What is VT/O/VLDG - Answer-Take off speed.
Equation is:
Vt/o= 1.2 * sqr rt(2w/rho*S*clmax)
IASt/o is the same thing just rho knot
Vldg=1.3 * sqr rt(2w/rho*S*clmax)
IASldg is the same thing just rho knot
DEFINE takeoff and landing airspeeds in terms of stall speed - Answer-It is affected by
the same factors that affect stall speed.
DESCRIBE the effects on takeoff and landing performance, given variations in weight,
altitude, temperature, and humidity - Answer-Takeoff:
Increase in Density altitude means a decrease in air density which requires more t/o
velocity and decreases the amount of thrust the engine can produce.
- decreases the min t/o roll and increase the required t/o distance
4 H Club
- Hot, heavy, humid, and high
- whenever 3 or more are present expect extended t/o and landing distance.
St/o (min t/o distance) = W^2/g*rho*S*clmax(T-D-FR) FR (Friction rolling force)
Landing:
4 h Club applies
Sldg (landing distance) = W^2/g*rho*S*clmax(FR+D-T) FR (Friction rolling force)
EXPLAIN the requirements yielding max range and max endurance in relation to the
power curve - Answer-Max endurance is found at a velocity less than L/Dmax and an
angle of attack greater than L/DmaxAoA for a turboprop.
Max Range is found at L/DmaxAoA and velocity.
DESCRIBE the effect of altitude on max range and max endurance performance -
Answer-Since the temperature drops as altitude increases, the engine burns less fuel,
increasing max range and endurance both increase.
DEFINE maximum glide range and maximum glide endurance profiles - Answer-Max
glide range: max distance covered in a glide. Fly at L/DMaxAoA - most effective AoA
In time of no runway, we need max endurance. most time in the air.
QUESTIONS WITH 100% CORRECT
ANSWERS
Describe boundary layer separation in regards to adverse pressure gradient - Answer-
Airflows from leading edge (high pressure) towards the point of max thickness (low
pressure) resulting in a favorable pressure gradient.
- This assists the boundary layer in adhering to the surface with high kinetic energy.
As the air flows from the point of max thickness (low pressure) to the trailing edge (high
pressure), it encounters a adverse pressure gradient. this impeded the flow of the
boundary layer.
Adverse pressure gradient is strongest when:
- high AoA
- high lift conditions
If the boundary layer does not have a sufficient amount of kinetic energy to counteract
the adverse pressure gradient, a stall occurs.
Define Stall - Answer-An increase in AoA results in a decrease in Cl.
EXPLAIN the difference between true and indicated stall speed - Answer-Min airspeed
required to maintain level flight occurs at ClMaxAoA. True uses density at current
altitude and stall speed will be affected by altitude. Indicated uses density on standard
day and will not be affected by altitude.
What is the equation for Stall speed and indicated stall speed - Answer-Vs = sqr rt
(2W/rho*s*Clmax)
IASs = sqr rt(2W/rhoknot*s*CLmax)
EXPLAIN the effects of gross weight, altitude, and flaps given the stall
speed equation - Answer-As weight increases, stall speed increases
As altitude increases, stall speed increases
As flaps are lowered, stall speed decreases
EXPLAIN the difference between speeds with respect to power on and
power off stalls - Answer-Power on stall = Lower Stall speed
Power off stall = higher stall speed
, Describe the relationship between the wings during a spin - Answer-During a spin, the
lower wing is more stalled and has a higher AoA than the higher wing which is less
stalled and at a lower AoA.
What is VT/O/VLDG - Answer-Take off speed.
Equation is:
Vt/o= 1.2 * sqr rt(2w/rho*S*clmax)
IASt/o is the same thing just rho knot
Vldg=1.3 * sqr rt(2w/rho*S*clmax)
IASldg is the same thing just rho knot
DEFINE takeoff and landing airspeeds in terms of stall speed - Answer-It is affected by
the same factors that affect stall speed.
DESCRIBE the effects on takeoff and landing performance, given variations in weight,
altitude, temperature, and humidity - Answer-Takeoff:
Increase in Density altitude means a decrease in air density which requires more t/o
velocity and decreases the amount of thrust the engine can produce.
- decreases the min t/o roll and increase the required t/o distance
4 H Club
- Hot, heavy, humid, and high
- whenever 3 or more are present expect extended t/o and landing distance.
St/o (min t/o distance) = W^2/g*rho*S*clmax(T-D-FR) FR (Friction rolling force)
Landing:
4 h Club applies
Sldg (landing distance) = W^2/g*rho*S*clmax(FR+D-T) FR (Friction rolling force)
EXPLAIN the requirements yielding max range and max endurance in relation to the
power curve - Answer-Max endurance is found at a velocity less than L/Dmax and an
angle of attack greater than L/DmaxAoA for a turboprop.
Max Range is found at L/DmaxAoA and velocity.
DESCRIBE the effect of altitude on max range and max endurance performance -
Answer-Since the temperature drops as altitude increases, the engine burns less fuel,
increasing max range and endurance both increase.
DEFINE maximum glide range and maximum glide endurance profiles - Answer-Max
glide range: max distance covered in a glide. Fly at L/DMaxAoA - most effective AoA
In time of no runway, we need max endurance. most time in the air.
