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The CORRECT choice is (a) Roll, pitch and yaw

The explanation is: The THREE critical FLIGHT dynamics parameters are roll, pitch and yaw. They may also be referred to as the angles of rotation w.r.t. the aircraft’s three principal axes about its CENTER of gravity.

Right answer is (a) A sideslip angle arises

The BEST explanation: When an AIRCRAFT yaws about its center of gravity, it CREATES a sideslip angle. It is the angle between the wheels of an aircraft and the direction in which the aircraft is TRAVELLING.

Correct CHOICE is (d) Reynolds Number

Best explanation: Viscosity of the flow is GIVEN by Reynolds Number. It is REPRESENTED by Re. Mach number indicates the COMPRESSIBILITY of flow and Knudsen number indicates rarefaction of the flow.

The correct CHOICE is (b) Absolute temperature

For explanation: Absolute temperature is not an aerodynamic coefficient. However, pressure coefficient, LIFT coefficient and DRAG coefficient are all aerodynamic coefficients. A few other aerodynamic coefficients are lateral force coefficient and FRICTION coefficient.

Right choice is (B) False

Easy EXPLANATION: Flight dynamics studies the stability and control of VEHICLES travelling through air. It does not study the efficiency of these vehicles; however, flight dynamics parameters are designed so as to IMPROVE the efficiency of these vehicles.

Right OPTION is (c) Zero bank angle

The explanation: The equilibrium roll angle is known as zero bank angle; it may ALSO be called wings level. The THREE CRITICAL flight dynamics refer to rotations about the respective axes STARTING from a defined equilibrium state.

Right choice is (a) GRAVITATIONAL force

The EXPLANATION: The most dominant force in spacecraft flight dynamics, is the gravitational force. This is because AERODYNAMIC forces affecting the spacecraft in air, are very small, thereby making gravitational force dominant.

The correct answer is (a) True

For explanation: AIRCRAFTS increase or DECREASE the lift generated by the WINGS, by increasing or decreasing the angle of ATTACK. Angle of attack is adjusted by changing the position of the NOSE of an aircraft.

Correct choice is (c) Electromagnetic force

Easiest explanation: SPACECRAFT flight DYNAMICS does not INCLUDE electromagnetic force. However, propulsive force, lift and drag and gravitational force are all part of spacecraft flight dynamics. Propulsive forces are most DOMINANT in rockets.

Right CHOICE is (b) Angle of attack of the wing and the angle of attack of the VERTICAL tail

For explanation: The two major sources of change in the AERODYNAMIC FORCES and moments applied to an aircraft are the angle of attack of the wing and the angle of attack of the vertical tail. The two angles are important to maintain the center of gravity of an aircraft.

The CORRECT option is (d) Drag

The EXPLANATION: The aircrafts are STREAMLINED from NOSE to tail to reduce drag on the aircraft. Increased drag reduces the airspeed of an aircraft and hence increases flying time.

Correct ANSWER is (a) SIDESLIP ANGLE

For explanation I would say: The angle of attack of the vertical tail is also known as Sideslip angle. It may also be REFERRED to as beta. Similarly, the angle of attack of the wing is referred to as alpha.

Correct answer is (d) Control systems

Easy explanation: The actuator is a part of the control system in an aircraft. BASICALLY, an actuator is a mover that requires a source of energy ALONG with a control signal. The actuator WORKS in such a WAY, that it CONVERTS the incoming signal’s energy into mechanical signals.

The correct OPTION is (c) Elevon

Explanation: The combination of AILERONS and elevators is CALLED elevon. Their RESPECTIVE control inputs are also combined and it reduces the pilot’s workload. They are mostly used on tailless AIRCRAFTS.

The correct option is (a) TRUE

The explanation: True, ailerons are used to steer the aircraft either left or right. They are mounted on the edge of each WING and work in OPPOSITE directions. Raising the aileron, reduces the lift on the wing and lowering the aileron, INCREASES the lift.

The correct choice is (d) Elevator

To elaborate: The elevator is a FLIGHT control SURFACE controlling the pitch of an aircraft. It is also RESPONSIBLE for adjusting the angle of attack, and hence the LIFT of an aircraft. It is usually located at the ear of an aircraft.

Right choice is (c) Rudder

To explain: The PRIMARY control of yaw is with the rudder. Yaw CHANGES the DIRECTION in which the AIRCRAFT’s nose is POINTING. In addition to the rudder, ailerons also have an effect on the yaw.

The correct answer is (b) Wing

Explanation: Canard refers to a wing arrangement in aircrafts. In canard CONFIGURATION, a small forewing is placed ahead of the MAIN wing. The WRIGHT FLYER of 1903 had a canard arrangement.

The CORRECT OPTION is (b) Ailerons

To EXPLAIN I would SAY: The ailerons are part of the primary cockpit flight controls. The roll and pitch of the AIRCRAFT can be adjusted using the ailerons. Slats, spoilers and air brakes are part of the secondary flight controls.

Right answer is (d) Unmanned aerial vehicles

The best I can explain: UAVs REFERS to unmanned aerial vehicles. These are vehicles without a human pilot on board. Examples of UAVs are spaceships and drones. They are controlled USING a ground BASED CONTROLLER and a communication system.

The correct answer is (C) Perpendicular

The EXPLANATION: An AIRCRAFT whose left WING is pointing straight down, will have its transverse axis perpendicular to the ground. Further, its VERTICAL axis will be parallel w.r.t. the ground. These axes are relative to the earth and will change with the change in position of the aircraft.

Correct answer is (a) TRUE

The explanation is: True. Spoilers are USED to reduce lift on an AIRCRAFT by hampering the flow of WIND over its wings. They are used for reducing lift while landing an aircraft. They allow aircraft to lose altitude without gaining SIGNIFICANT airspeed.

Right choice is (a) Roll

The explanation: The AXIS passing through the AIRCRAFT from NOSE to TAIL is CALLED as longitudinal axis. Rotation about the longitudinal axis is called roll. Further, the angular displacement about it is called bank.

The correct ANSWER is (d) Fly-by-wire

Easiest explanation: FBW refers to fly-by-wire. Fly-by-wire is a CONTROL system that replaces manual flight controls of an aircraft with an electronic interface. Flight controls are controlled through electronic SIGNALS, which are transmitted USING wires.

The CORRECT option is (c) Radars

Explanation: Radars are not a part of flight control SYSTEMS. However, AILERONS, ELEVATORS and flaps are all part of the flight control systems. Some other flight control systems are elevens and FLAPERONS.

The correct answer is (b) Empennage

To explain: The rudder is a part of the empennage. More specifically, it is mounted on the vertical stabilizer, at the REAR end of the aircraft. If the pilot PUSHES the left PEDAL, rudder is deflected left and similarly when the pilot pushes the RIGHT pedal, rudder is deflected right.

Right choice is (d) To increase the EFFECTIVE curvature of the wing

Explanation: Flaps are deflected downwards to increase the effective curvature of the wing. Flaps are USED during descent or TAKE off. They are used to reduce stalling SPEED of an aircraft and are mostly used during LOW speed.

The correct CHOICE is (c) Transverse AXIS

For explanation I would say: The transverse axis passes from wingtip to wingtip through an aircraft. It MAY also be called the lateral axis. Rotation along this axis is called PITCH, which is controlled by elevators.