Category: Aircraft Performance Objective Questions

Aircraft Performance Interview Questions and Answers on “Fixed-Wing Aircraft – Operational Performance”.

1. Factors that affect the aircraft performance during take-off are mass of the aircraft during take-off, air density, temperature and runway conditions.
a) True
b) False
Answer: a
Clarification: Factors that the affect aircraft performance during take-off are mass of the aircraft during take-off, air density, temperature and runway conditions. The speed of wind and flap setting and airframe contamination are the other factors that affect the aircraft performance during take-off.

2. MTOW stands for _________
a) Maximum permissible Take-Off Weight
b) Minimum permissible Take-Off Weight
c) Maximal permissible Take-Off Weight
d) Minimal permissible Take-Off Weight
Answer: a
Clarification: MTOW stands for Maximum permissible Take-Off Weight. MTOW is the maximum weight of an aircraft at which a pilot is allowed to take-off the aircraft. This is caused due to structural limits of the aircrafts.

3. The basic requirements for safe flight are that the space required for the aircraft to maneuver should never exceed the space available.
a) True
b) False
Answer: a
Clarification: The basic requirements for safe flight are that the space required for the aircraft to maneuver should never exceed the space available this is because if the space is insufficient for the aircraft to perform a maneuver then there may be a failure of the aircraft due to this aircraft getting hindered by some factor.

4. What is operational performance of an aircraft?
a) The performance of an aircraft which is related to the aircraft above ground level
b) The performance of an aircraft which is related to the aircraft engine
c) The performance of an aircraft which is related to the aircraft when it is on ground
d) The performance of an aircraft which is related to the aircraft taxing
Answer: a
Clarification: Operational performance of an aircraft is the performance of an aircraft which is related to the aircraft above ground level. It includes aircraft cruise angle, altitude, temperature, engine failure, fuel management and also take-off performances.

5. Aircraft weight is the only controllable variable that can be used to ensure that space required for the maneuver doesn’t exceed the space available.
a) True
b) False
Answer: a
Clarification: Aircraft weight is the only controllable variable that can be used to ensure that space required for the maneuver doesn’t exceed the space available. As a rule of aircraft performance the space required for an aircraft to maneuver must be always less than the space available. As a result the aircraft weight much be checked to avoid complications that occur due to space required being more than space available.

6. What is MTOW of an aircraft?
a) The maximum weight of an aircraft at which a pilot is allowed to attempt to land the aircraft
b) The maximum weight of an aircraft at which a pilot is allowed to attempt to take-off the aircraft
c) The minimum weight of an aircraft at which a pilot is allowed to attempt to take-off the aircraft
d) The minimum weight of an aircraft at which a pilot is allowed to attempt to land the aircraft
Answer: b
Clarification: MTOW stands for Maximum permissible Take-Off Weight. MTOW is the maximum weight of an aircraft at which a pilot is allowed to take-off the aircraft. This is caused due to structural limits of the aircrafts.

7. A flight is carrying 130 passengers over a distance of 990km with a seating capacity of 140 and a yield of 7.9. Calculate the load factor.
a) 90%
b) 92.86%
c) 89.556%
d) 67.35%
Answer: b
Clarification: The answer is 92.86%. Given number of passengers travelling = 130, seating capacity=140 and a yield of 7.9.
We know percentage load factor=(frac{no. , of , passengers ,travelling*distance ,travelled}{no. ,of , seats*distance , travelled}) x 100%
On substituting the values,
Load factor=(frac{130*990}{140*990}) x 100%
Load factor=92.86%.

8. A flight is carrying 130 passengers over a distance of 990km with a seating capacity of 140 and a yield of 7.9. Calculate the passenger revenue.
a) 143780
b) 1016730
c) 1094940
d) 1524263
Answer: b
Clarification: The answer is 1016730. Given number of passengers travelling = 130, seating capacity=140 and a yield of 7.9. We know that passenger revenue=Revenue passenger kilometers*yield where Revenue passenger kilometers=number of passengers travelling*distance travelled.
On substituting the values
Revenue passenger kilometers=130*990
Revenue passenger kilometers=128700
On substituting revenue passenger kilometers in passenger revenue formula
Passenger revenue=128700*7.9.

9. A flight is carrying 130 passengers over a distance of 990km with a seating capacity of 140 and a yield of 7.9. Calculate the Revenue passenger kilometers.
a) 138600
b) 124570
c) 128700
d) 124560
Answer: c
Clarification: The answer is 128700. Given number of passengers travelling = 130, seating capacity=140 and a yield of 7.9. We know that revenue passenger kilometers=number of passengers travelling*distance travelled.
On substituting the values
Revenue passenger kilometers=130*990
Revenue passenger kilometers=128700.

10. A flight is carrying 130 passengers over a distance of 990km with a seating capacity of 140 and a yield of 7.9. Calculate the available seats kilometer.
a) 148700
b) 138600
c) 128700
d) 154800
Answer: b
Clarification: The answer is 138600. Given number of passengers travelling = 130, seating capacity=140 and a yield of 7.9. We know that available seats kilometer=number of seats available*distance travelled.
On substituting the values
Available seats kilometer=130*990
Available seats kilometer=128700.

Aircraft Performance for Interviews,

Aircraft Performance Multiple Choice Questions on “Minimum Power Speed”.

1. Power is defined as ___________
a) product of force and acceleration
b) ability to do work
c) rate of doing work
d) capacity to do work
Answer: c
Clarification: Power is defined as rate of doing work. In another terms power can be defined as product of force and velocity. The standard S.I. unit of power is Watt. The other units are Watt, Kilowatt, Megawatt, Gigawatt, Horse power. 1 HP= 0.746 KW.

2. Drag power of an aircraft is achieved by multiplying drag force with true airspeed.
a) True
b) False
Answer: a
Clarification: Drag power of an aircraft is achieved by multiplying drag force with true airspeed. The formula for drap power is given as P(sqrt{sigma})=DV_e=YV_e³+(frac{ZW^2}{V_e}) where Y is a constant, V_e is velocity, W is weight, Z is constant and D is total drag and P is power.

3. Which of the following is correct relation between EAS and minimum power speed?
a) V_emP=(sqrt[3]{frac{ZW^2}{3Y}})
b) V_emP=(sqrt[4]{frac{ZW^2}{Y}})
c) V_emP=(sqrt[4]{frac{ZW^2}{3Y}})
d) V_emP=(sqrt[4]{frac{ZW}{3Y}})
Answer: c
Clarification: The correct relation between EAS and minimum power speed is V_emP=(sqrt[4]{frac{ZW^2}{3Y}}) where Y is a constant, V_emP is minimum power speed, W is weight, Z is constant. The true air speed have to be converted into equivalent airspeed before multiplication to derive the drag power equation.

4. Which of the following is correct relation between EAS and drag power?
a) P(sqrt{sigma})=YV_e³+(frac{ZW^2}{V_e})
b) P(sqrt{sigma})=YV_e³–(frac{ZW^2}{V_e})
c) P(sqrt{sigma})=YV_e²-+(frac{ZW^2}{V_e})
d) P(sqrt{sigma})=YV_e²–(frac{ZW^2}{V_e})
Answer: a
Clarification: The correct relation between EAS and drag power is P(sqrt{sigma})=YV_e³+(frac{ZW^2}{V_e}) where Y is a constant, V_e is velocity, W is weight, Z is constant and D is total drag and P is power.

5. The true air speed have to be converted into calibrated airspeed before multiplication to derive the drag power equation.
a) True
b) False
Answer: b
Clarification: The true air speed have to be converted into equivalent airspeed before multiplication to derive the drag power equation. The equation of the drag power equation is P(sqrt{sigma})=YV_e³+(frac{ZW^2}{V_e}) where Y is a constant, W is weight, V_e is velocity, Z is constant and D is total drag and P is power.

6. Which of the following equation is correct?
a) P(sqrt{sigma})=YV_e³+(frac{ZW^2}{V_e})
b) V_emP=(sqrt[4]{frac{ZW}{3Y}})
c) P(sqrt{sigma})=YV_e²+(frac{ZW^2}{V_e})
d) V_emP=(sqrt[3]{frac{ZW^2}{3Y}})
Answer: a
Clarification: The correct equation is P(sqrt{sigma})=YV_e³+(frac{ZW^2}{V_e}) where Y is a constant, W is weight, V_e is velocity, Z is constant and D is total drag and P is power.The true air speed have to be converted into equivalent airspeed before multiplication to derive the drag power equation.

7. The minimum drag speed and minimum power speed are related by ___________
a) (sqrt[4]{3})
b) (sqrt[4]{2})
c) (sqrt[2]{3})
d) (sqrt[3]{3})
Answer: a
Clarification: The minimum drag speed and minimum power speed are related by (sqrt[4]{3}) i.e. 1.316. The minimum drag speed multiplied by the factor (sqrt[4]{3}) i.e. 1.316 gives the minimum power speed.

8. The minimum drag is related to the performance of the aircraft with thrust producing engines.
a) True
b) False
Answer: a
Clarification:The minimum drag is related to the performance of the aircraft with thrust producing engines whereas the minimum power speed is related to the performance of the aircraft with power producing engines.

9. The minimum power speed is related to the performance of the aircraft with thrust producing engines.
a) True
b) False
Answer: b
Clarification: The minimum power speed is related to the performance of the aircraft with power producing engines whereas the minimum drag is related to the performance of the aircraft with thrust producing engines.

10. What is the relation between true air speed and equivalent air speed?
a) V_T=(frac{V_e}{sqrt{sigma}})
b) V_T=(frac{V_e}{4sqrt{sigma}})
c) V_e=(frac{V_T}{sqrt{sigma}})
d) V_T=(frac{V_e}{3sqrt{sigma}})
Answer: a
Clarification: The relation between true air speed and equivalent air speed is V_T=(frac{V_e}{sqrt{sigma}}) where V_T is true air speed, V_e is equivalent air speed and σ is a constant.The true air speed have to be converted into equivalent airspeed before multiplication to derive the drag power equation.

Aircraft Performance Questions and Answers for Aptitude test on “Climb and Descent Performance with Power-Producing Engines”.

1. The propulsive force developed by the engine-propeller combination is given by _______
a) (frac{eta V}{P})
b) (frac{eta P}{V})
c) (frac{P}{V})
d) (frac{VP}{eta})
Answer: b
Clarification: The propulsive force developed by the engine-propeller combination is given by (frac{eta P}{V}) where η is propeller efficiency, P is power and V is velocity. The equation of power-producing engine is written as (frac{eta P}{V})-D=Wsinγ₂.

2. The gradient of climb is given by _____________
a) (Big[frac{eta P}{V}-WBig]frac{1}{D})=sinγ₂
b) (Big[frac{eta P}{V}+DBig]frac{1}{W})=sinγ₂
c) (Big[frac{eta P}{V}-DBig]frac{1}{W})=sinγ₂
d) (Big[frac{eta P}{V}+WBig]frac{1}{D})=sinγ₂
Answer: c
Clarification: The gradient of climb is given by (Big[frac{eta P}{V}-DBig]frac{1}{W})=sinγ₂ where η is propeller efficiency, P is power, V is velocity, D is drag and γ is the angle at which the force is acting on the aircraft. The value of gradient of climb is more when the propulsive force is maximum.

3. The rate of climb is given by _____________
a) [ηP+DV](frac{1}{W})=(frac{dH}{dt})
b) [ηP-DV](frac{1}{W})=(frac{dH}{dt})
c) [ηP+DV]W=(frac{dH}{dt})
d) [ηP-DV]W=(frac{dH}{dt})
Answer: b
Clarification: The rate of climb is given by [ηP-DV](frac{1}{W})=(frac{dH}{dt}) where η is propeller efficiency, P is power, V is velocity, D is drag and W is weight and dH/dt is vertical velocity. The rate of climb is maximum when power speed is minimum.

4. What is the relation between climb rate and power speed?
a) Climb rate increases at minimum power drag
b) Climb rate decreases at minimum power drag
c) Climb rate is independent of minimum power drag
d) Climb rate increases at maximum power drag
Answer: a
Clarification: Climb rate is maximum at minimum power drag. The rate of climb is given by [ηP-DV](frac{1}{W})=(frac{dH}{dt}) where η is propeller efficiency, P is power, V is velocity, D is drag and W is weight and dH/dt is vertical velocity.

5.The relative airspeed for maximum gradient of climb is a function of engine power.
a) True
b) False
Answer: a
Clarification: The relative airspeed for maximum gradient of climb is a function of engine power. The best climb gradient is given by u⁴+λu-1=0 where u is airspeed and λ is dimensionless power.

6. What is the value of λ in gliding flight flying at minimum drag speed?
a) 3
b) 2
c) 1
d) 0
Answer: d
Clarification: In gliding flight the value of dimensionless power (λ) is zero (0) and the shallow glide angle is given by flying at the minimum drag speed. As the power increase the airspeed for maximum climb gradient decreases.

7. What is the relation betweenpower and airspeed for climb gradient?
a) Power increases with increase in airspeed
b) Power decreases with increase in airspeed
c) Power increases with decrease in airspeed
d) Power is unaffected by the airspeed
Answer: c
Clarification: The relation between power and airspeed for climb gradient is that the power increases with decrease in airspeed for maximum climb gradient. The best climb gradient is attained by flying at airspeeds less than the minimum power speeds.

8. The best climb gradient is attained by flying at airspeeds less than the minimum power speeds.
a) True
b) False
Answer: a
Clarification: The relation between power and airspeed for climb gradient is that the power increases with decrease in airspeed for maximum climb gradient. The best climb gradient is attained by flying at airspeeds less than the minimum power speeds.

9. What is the value that maintains maximum rate and minimum power speed of the aircraft?
a) 1/(sqrt[4]{3})
b) 1/(sqrt[3]{3})
c) u²/(sqrt[4]{3})
d) u²/(sqrt[3]{3})
Answer: a
Clarification: At the maximum rate i.e. dv/du=0 the value of u=1/(sqrt[4]{3}) which is the minimum power speed. The rate of climb is given by λ-(frac{1}{2})[u³+u^-1]=E_maxv where λ is dimensionless power, u is airspeed and E_max is endurance.

10. At what rate does the minimum sink rate occur in a gliding flight?
a) It occurs at minimum power speed
b) It occurs at maximum power speed
c) It occurs at minimum airspeed
d) It occurs at maximum airspeed
Answer: a
Clarification: The minimum sink rate occur in a gliding flight at minimum power speed. The rate of climb is given by λ-(frac{1}{2})[u³+u^-1]=E_maxv where λ is dimensionless power, u is airspeed and E_max is endurance.

Aircraft Performance for Aptitude test,

Aircraft Performance Multiple Choice Questions on “Characteristics of Atmosphere”.

1. What is the ideal gas equation?
a) P=nRT
b) PV=nRT
c) PV=ρRT
d) Pρ=RT
Answer: b
Clarification: The ideal gas equation is PV=ρRT, where
P=pressure of gas (Units=N/m²)
V=volume of gas (Units=m³)
ρ=density of gas (Units=Kg/m³)
R=universal gas constant (Units=Nm/kg-K)
T=temperature of gas (Units=K).

2. Between the poles and the equator the mean global temperature roughly follows a sine curve.
a) True
b) False
Answer: a
Clarification: Between the poles and the equator the mean global temperature roughly follows a sine curve. This is due to the changes of temperature near the equator and the poles. At the equator the mean seasonal variation is small and the mean temperature is high whereas at the poles the mean seasonal variation is large and the mean temperature is low.

3. Which of the following is the major reason for the global atmosphere pressure distribution?
a) Convective air flow
b) Conductive air flow
c) Radiation air flow
d) Conductive and radiation air flow
Answer: a
Clarification: The convective air flow is the major reason for the global atmosphere pressure distribution. The Coriolis forces cause the air flow to swirl and create a series of convectional current cells which results in the general pattern of high and low pressure region over the surface of the earth.

4. What is meant by Coriolis force?
a) An earth force that tends to deflect the moving objects on earth
b) An earth force that tends to vary the temperature
c) An earth force that tends to vary the pressure
d) An earth force that tends to vary the gravitational force
Answer: a
Clarification: Coriolis force is an earth force that acts perpendicular to the direction of motion and to the axis of rotation. This force tends to deflect moving objects to the left in the southern hemisphere and towards the right in the northern hemisphere.

5. Which of the following holds a correct relation between pressure, temperature and altitude?
a) Pressure increases, temperature decreases, altitude increases
b) Pressure decreases, temperature decreases, altitude increases
c) Pressure decreases, temperature increases, altitude increases
d) Pressure decreases, temperature decreases, altitude decreases
Answer: b
Clarification: As the pressure decreases there will be a temperature decreases during an increase in altitude. This is based on ideal gas equation PV=nRT where,
P=pressure of gas (Units=N/m²)
V=volume of gas (Units=m³)
ρ=density of gas (Units=Kg/m³)
R=universal gas constant (Units=Nm/kg-K)
T=temperature of gas (Units=K).

6. What are the percentages of nitrogen, oxygen, argon and carbon dioxide in atmosphere?
a) 78%, 21%, 0.9%, 0.03%
b) 75%, 24%, 0.7%, 0.03%
c) 71%, 28%, 0.9%, 0.04%
d) 75%, 24%, 0.9%, 0.05%
Answer: a
Clarification: The percentages of nitrogen, oxygen, argon and carbon dioxide in atmosphere are 78%, 21%, 0.9%, 0.03%. The atmosphere also consists of other inert gases, dust particles, water vapor and moisture in minute quantities.

7. What is the value of characteristic gas constant(R) in Nm/kg-K?
a) 287.05287
b) 2.8705287
c) 2870.5287
d) 2.8705287
Answer: a
Clarification: The value of characteristic gas constant(R) is 287.05287 Nm/kg-K and the value of universal gas constant (R₀) is 8.3145 J/mol. The relation between them is R=(frac{R0}{M}) , where R₀ is universal gas constant; R is characteristic gas constant and M is molecular weight of the substance.

8. The ratio of specific heats (γ) of air is _________
a) 1.6
b) 1.7
c) 1.4
d) 1.8
Answer: c
Clarification: The ratio of specific heats (γ) of air is 1.4. Ratio of specific heats is the ratio of specific heat of air at constant pressure to the specific heat of air at constant volume, i.e. (frac{C_p}{C_v})=γ. C_p of air is 1.008 kJ/kg-K; C_v of air is 0.721 kJ/kg-K at standard levels. So γ=(frac{1.008}{0.721})=1.4.

9. At the equator the mean seasonal variation is small and the mean temperature is high whereas at the poles the mean seasonal variation is large and the mean temperature is low.
a) True
b) False
Answer: a
Clarification: At the equator the mean seasonal variation is small and the mean temperature is high whereas at the poles the mean seasonal variation is large and the mean temperature is low. This is due to the change in temperature with respect to the altitude of the atmosphere. It is almost similar to a sine graph.

10. Regions of low pressure, cyclones and high pressure, anti-cyclones are formed by effects of convection currents in the atmosphere.
a) True
b) False
Answer: a
Clarification: Regions of low pressure, cyclones and high pressure, anti-cyclones are formed by effects of convection currents in the atmosphere. This is caused due to the air transporting from higher temperature regions to the lower temperature regions.

11. According to ISA atmospheric model what is the value of datum atmospheric pressure in N/m²?
a) 101325
b) 101335
c) 101336
d) 101326
Answer: a
Clarification: According to ISA atmospheric model what is the value of datum atmospheric pressure is 101325 N/m². It can also be written in 1atm or 1.01325 bar or 101325 Pascal. The conversion of N/m² to bar is 1 bar=10⁵ N/m². The conversion of bar to Pascal is 1 bar=1 Pascal.

Aircraft Performance Multiple Choice Questions on “Thrust Producing Power Plant – 1”.

1. The forms of powerplant used in aircraft propulsion are ___________
a) thrust-producing and power producing
b) weight-producing and power producing
c) thrust-producing and weight producing
d) thrust-producing, power producing and weight producing
Answer: a
Clarification: The two forms of powerplant used in aircraft propulsion are thrust-producing and power producing. Thrust-producing engines include turbojet, turbofan and rocket while power producing engines are get engine and piston engine.

2. What is thrust producing powerplant?
a) Propulsive force that is directed by increasing momentum of the airflow
b) Propulsive force that is obtained from shaft power by propeller
c) Propulsive force that is directed by decreasing momentum of the airflow
d) Propulsive force that is obtained from engine power by propeller
Answer: a
Clarification: The two forms of powerplant used in aircraft propulsion are thrust-producing and power producing. A thrust-producing powerplant is the one whose propulsive force is obtained by increasing momentum of the airflow through the engine.

3. Which of the following is not a thrust-producing powerplant?
a) turbojet
b) turbofan
c) rocket
d) piston engine
Answer: d
Clarification: The two forms of powerplant used in aircraft propulsion are thrust-producing and power producing. A thrust-producing powerplant is the one whose propulsive force is obtained by increasing momentum of the airflow through the engine. Examples of thrust-producing powerplant are turbojet, turbofan and rocket.

4. The high-energy air is expelled from the nozzle of an aircraft with decreased momentum.
a) True
b) False
Answer: a
Clarification: The high-energy air is expelled from the nozzle of an aircraft with increased momentum to produce thrust to the aircraft. This process is occurred in the thrust-producing powerplant. Some examples of thrust-producing powerplant are turbojet, turbofan and rocket.

5. What is the function of the compressor in an aircraft?
a) To supply sufficient amount of air for combustion
b) Increase velocity
c) Decrease pressure
d) To cut off the air flow inside the aircraft
Answer: a
Clarification: The function of the compressor in an aircraft to supply sufficient amount of air for combustion. In a compressor the velocity may increase or decrease accordingly but the pressure increases.

6. What is net propulsive force?
a) The stream force exited at the exit of the engine
b) The difference between the stream force entering and leaving the engine
c) The stream force entering at the entrance of the engine
d) The product of stream force entering and leaving the engine
Answer: b
Clarification: The net propulsive force is the difference between the stream force entering and leaving the engine. It is represented by F_N. The thrust produced by an aircraft is depended on the net propulsive force.

7. What is gross thrust?
a) Thrust produced at the exit of the nozzle
b) The difference between the stream force entering and leaving the engine
c) The stream force exited at the exit of the engine
d) The product of stream force entering and leaving the engine
Answer: a
Clarification: The gross thrust is the thrust produced at the exit of the nozzle. It is represented by F_G. It is also equal to the rate of change of momentum at the exhaust gas flow. The equation is given as F_G=ṁV_j where F_G is gross thrust, ṁ is mass flow rate and V_j is exit velocity.

8. Flow due to intake flow is known as momentum drag.
a) True
b) False
Answer: a
Clarification: Flow due to intake flow is known as momentum drag. It is the rate of change of momentum in the intake flow. It is represented by D_m. The equation is D_m=ṁV where D_m is momentum drag, ṁ is mass flow rate and V is air intake flow.

9. The net propulsive thrust is given by _________
a) F_N=F_G-D_m
b) F_N=F_G+D_m
c) F_N=F_G*D_m
d) F_N=F_G/D_m
Answer: a
Clarification: The net propulsive thrust is given by F_N=F_G-D_m where F_N is net propulsive force, F_G is gross thrust and D_m is momentum drag. The net propulsive force is the difference between the stream force entering and leaving the engine. Flow due to intake flow is known as momentum drag. The gross thrust is the thrust produced at the exit of the nozzle.

10. What kind of forces is responsible for airframe drag?
a) Forces resulting from external flow
b) Forces resulting from internal flow
c) Forces resulting from discontinuous flow
d) Forces resulting from continuous flow
Answer: a
Clarification: The external flow can result in generation of forces. These forces that are caused due to external flow is known as airframe drag. In general there are three types of drags. They are parasitic drag, induced drag and wave drag.

Aircraft Performance Multiple Choice Questions on “Climb and Descent Performance with Mixed Power Plants”.

1. Which of the following is the correct performance equation for mixed power-plants?
a) E_maxsinγ₂=(Big[frac{lambda}{u}+tau Big]-frac{1}{2}[u^2+u^{-2}])
b) E_maxsinγ₂=(Big[frac{lambda}{u}-tau Big]-frac{1}{2}[u^2-u^{-2}])
c) E_maxsinγ₂=(Big[frac{lambda}{u}+tau Big]-frac{1}{2}[u^2-u^{-2}])
d) E_maxsinγ₂=(Big[frac{lambda}{u}-tau Big]-frac{1}{2}[u^2+u^{-2}])
Answer: a
Clarification: The correct performance equation for mixed power-plants is given by the formula E_maxsinγ₂=(Big[frac{lambda}{u}+tau Big]-frac{1}{2}[u^2+u^{-2}]) where u is airspeed, γ is the angle at which the force is acting on the aircraft and τ is dimensionless thrust and E_max is endurance.

2. The best gradient of climb is attained at _____________
a) airspeed below maximum drag speed
b) airspeed below maximum power speed
c) airspeed below minimum power speed
d) airspeed below minimum drag speed
Answer: d
Clarification: The best gradient of climb is attained at airspeed below minimum drag speed. The best rate of climb is attained at airspeed above minimum drag speed. The actual airspeeds will be a function of excess propulsive thrust.

3. The best rate of climb is attained at _____________
a) airspeed above maximum drag speed
b) airspeed above maximum power speed
c) airspeed above minimum power speed
d) airspeed above minimum drag speed
Answer: c
Clarification: The best gradient of climb is attained at airspeed below minimum drag speed. The best rate of climb is attained at airspeed above minimum drag speed. The actual airspeeds will be a function of excess propulsive thrust.

4. At which speed the maximum rate of climb occurs?
a) u=0.76
b) u=0.98
c) u=1
d) u=2
Answer: a
Clarification: The maximum rate of climb occurs at the airspeed u=0.76 m/sec. The best gradient of climb is attained at airspeed below minimum drag speed. The best rate of climb is attained at airspeed above minimum drag speed. The actual airspeeds will be a function of excess propulsive thrust.

5. The rate of climb of an aircraft is measured by _______
a) variometer
b) altimeter
c) pitot-static prob
d) gyroscope
Answer: a
Clarification: The rate of climb of an aircraft is measured by variometer. The best gradient of climb is attained at airspeed below minimum drag speed. The best rate of climb is attained at airspeed above minimum drag speed.

6. The advanced ratio is given by _______________
a) J=(frac{D}{nV})
b) J=(frac{nV}{D})
c) J=(frac{V}{nD})
d) J=(frac{n}{VD})
Answer: c
Clarification: The advanced ratio is given by J=(frac{V}{nD}) where J is advance ratio, V is velocity and D is propeller diameter and n is rotational speed. Propeller efficiency is depended on advanced ratio.

7. What is the use of partial climbs?
a) It is used for calculating climb rate
b) It is used for calculating gradient of climb
c) It is used for calculating speed
d) It is used for calculating velocity
Answer: a
Clarification: The use of partial climbs is to calculate rate of climb. The other method for calculating climb rate is level accelerated method. Level accelerated is best suitable for thrust producing engines. Partial climb is best suitable for power-producing engines.

8. The partial climb is best suitable for power-producing engines.
a) True
b) False
Answer: a
Clarification: The use of partial climbs is to calculate rate of climb. The other method for calculating climb rate is level accelerated method. Level accelerated is best suitable for thrust producing engines. Partial climb is best suitable for power-producing engines.

9. Level accelerated is best suitable for thrust producing engines.
a) True
b) False
Answer: a
Clarification: The use of partial climbs is to calculate rate of climb. The other method for calculating climb rate is level accelerated method. Level accelerated is best suitable for thrust producing engines. Partial climb is best suitable for power-producing engines.

10. There is an alternative method to calculate climb rate and gradient.
a) True
b) False
Answer: a
Clarification: The alternative method is to measure the maximum excess thrust and power by level flight accelerations. The other method for calculating climb rate is level accelerated method.