Aircraft Performance Multiple Choice Questions on “High Performance Climb”.
1. If ETS is 400kts, what is the acceleration associated with it?
a) 40kts/min
b) 4000kts/min
c) 4kts/min
d) 400kts/min
Answer: d
Clarification: If ETS is 400kts, then the associated acceleration with it is 400kts/min. This is during the climb phase of the aircraft. Thus it concludes that the climb is the combination of the potential and kinetic energy.
2. Specific total energy is ________
a) the potential energy per unit mass
b) the kinetic energy per unit mass
c) the potential and kinetic energy per unit mass
d) the potential and kinetic energy per unit time
Answer: c
Clarification: Specific total energy is the potential and kinetic energy per unit mass. This is few times referred as the energy height as it represents the height of the aircraft would attain if all the kinetic energy is converted to potential energy.
3. STE stands for ___________
a) Standard total energy
b) Specific terminal energy
c) Standard terminal energy
d) Specific total energy
Answer: d
Clarification: Specific total energy is the potential and kinetic energy per unit mass. This is few times referred as the energy height as it represents the height of the aircraft would attain if all the kinetic energy is converted to potential energy.
4. Which of the following is the correct formula for STE?
a) Es=(Big{H-frac{V^2}{2g}Big})
b) Es=(Big{H+frac{V^2}{g}Big})
c) Es=(Big{H+frac{V^2}{2}Big})
d) Es=(Big{H+frac{V^2}{2g}Big})
Answer: d
Clarification: The correct formula for specific total energy is given by the formula Es=(Big{H+frac{V^2}{2g}Big}) where ‘Es’ is specific total energy, ‘H’ is height, ‘V’ is velocity and ‘g’ is acceleration due to gravity. Specific total energy is the potential and kinetic energy per unit mass. This is few times referred as the energy height as it represents the height of the aircraft would attain if all the kinetic energy is converted to potential energy.
5. SEP stands for ___________
a) Specific Efficient Power
b) Specific Excess Power
c) Standard Efficient Power
d) Standard Excess Power
Answer: b
Clarification: SEP stands for specific excess power. It is equal to the rate of change of specific total energy (STE) and is used to increase the total energy of the aircraft which is in a combination with climb and acceleration.
6. The formula for SEP is given by ___________
a) [FN-D](frac{V}{W}=frac{d}{dt}Big{H+frac{V^2}{2g}Big})
b) [FN+D](frac{V}{W}=frac{d}{dt}Big{H+frac{V^2}{2g}Big})
c) [FN-D](frac{V}{W}=frac{d}{dt}Big{H-frac{V^2}{2g}Big})
d) [FN+D](frac{V}{W}=frac{d}{dt}Big{H-frac{V^2}{2g}Big})
Answer: a
Clarification: The formula for SEP is given by [FN-D](frac{V}{W}=frac{d}{dt}Big{H+frac{V^2}{2g}Big}) where FN is force, D is drag, H is height, V is velocity, g is acceleration due to gravitation. SEP stands for specific excess power. It is equal to the rate of change of specific total energy (STE) and is used to increase the total energy of the aircraft which is in a combination with climb and acceleration.
7. What are the methods followed to gain advantage in air to air combat mission?
a) Accelerate to the operational height in a short time
b) Decelerate to the operational height in a short time
c) Accelerate to the operational height in a long time
d) Decelerate to the operational height in a long time
Answer: a
Clarification: The gain in advantage of air to air combat mission is gained by accelerating to the operational height in a short time and obtaining an optimum mach number in that short span of time.
8. What is the operational technique in combat mission aircraft?
a) Minimizing the time required to increase the total energy of the aircraft to its combat height
b) Maximizing the time required to decrease the total energy of the aircraft to its combat height
c) Minimizing the time required to decrease the total energy of the aircraft to its combat height
d) Minimizing the time required to increase the total energy of the aircraft to its combat height
Answer: a
Clarification: The operational technique in combat mission aircraft is to minimize the time required to increase the total energy of the aircraft to its combat height. The gain in advantage of air to air combat mission is gained by accelerating to the operational height in a short time and obtaining an optimum mach number in that short span of time.
9. The time taken to increase the specific total energy will be minimized by maximizing the SEP.
a) True
b) False
Answer: a
Clarification: The time taken to increase the specific total energy will be minimized by maximizing the SEP. The formula for SEP is given by [FN-D](frac{V}{W}=frac{d}{dt}Big{H+frac{V^2}{2g}Big}) where FN is force, D is drag, H is height, V is velocity, g is acceleration due to gravitation. SEP stands for specific excess power. It is equal to the rate of change of specific total energy (STE) and is used to increase the total energy of the aircraft which is in a combination with climb and acceleration.
10. In transonic region the thrust is inversely proportional to drag.
a) True
b) False
Answer: a
Clarification: In transonic region the thrust is inversely proportional to drag. Acceleration across the transonic region can be assisted by reducing rate of climb of the aircraft but the priority is given to increase in kinetic energy of the aircraft.