Engineering Questions with Answers - Multiple Choice Questions
Rocket Propulsion – Flight Maneuver
1 - Question
Rocket propulsion thrust vector passes through the ___________ of the vehicle.
a) center of gravity
b) center of pressure
c) neutral point
d) maneuvering point
View Answer
Explanation: The thrust vector passes through the center of gravity for a rocket propulsion system. Because of that, no residual moments will be generated about the center of gravity.
2 - Question
An example for an unpowered maneuvering is ___________
a) coasting
b) translational maneuver
c) cruising
d) freefall
View Answer
Explanation: Coasting is an example for an unpowered maneuver. Cruising involves maintaining a steady level horizontal flight at a constant altitude. Several powered and unpowered segments of the flight trajectory can be grouped together under translational maneuvers.
3 - Question
What is the thrust required for a truly rotational maneuver?
a) Infinite
b) Zero
c) In the order of mega-Newtons
d) In the order of milli-Newtons
View Answer
Explanation: No thrust is required for a truly rotational maneuver. Only torque is generated in this case using couples.
4 - Question
What kind of maneuvers are typically provided by the reaction control systems?
a) Misaligned thrust maneuvers
b) Translational maneuvers
c) Truly rotational maneuvers
d) Circular maneuvers
View Answer
Explanation: Reaction control systems typically help in rotational maneuvers. It requires a set of 4 thrusters for to rotate the vehicle about any one axis in either of the two directions.
5 - Question
Which of the following processes requires accurately predetermined impulses for a rocket engine?
a) Launching
b) Re-entry
c) Orbit Injection
d) Coasting
View Answer
Explanation: Orbital injection or transferring the rocket vehicle from one orbit to another requires a predetermined, accurate amount of specific impulse. Here the thrust levels are lower in comparison to the launch stage
6 - Question
In the case of orbital transfer from one orbit to another, if the new orbit is higher, then the thrusts are applied in the opposite direction to the flight velocity vector.
a) True
b) False
View Answer
Explanation: The thrust in this case needs to be applied in the same direction as the flight velocity vector. If the new orbit is lower, then the thrust direction is opposite to the flight velocity vector. Transfer orbits are typically achieved using an electric propulsion system if the flight duration is supposed to be longer.
7 - Question
Which of the following is not a property of inflight correction maneuver?
a) Low thrust
b) Pulsing
c) Long duration
d) Uses reaction control systems
View Answer
Explanation: Inflight correction maneuvers are typically short duration maneuvers. They are intermittent (pulsing) operations performed with low thrust.
8 - Question
Station keeping maneuvers are ___________
a) orbit maintenance maneuvers
b) velocity adjustment maneuvers
c) first stage propulsion control
d) orbit transfer maneuvers
View Answer
Explanation: Station keeping maneuvers are orbit maintenance maneuvers. It keeps the spacecraft in its intended orbit and orbital position.
9 - Question
Which of the following is the most effective way of slowing a rocket during reentry and landing maneuver into the moon?
a) The atmospheric drag
b) Deploying landing parachutes
c) Reverse thrust
d) Deploying heat shields
View Answer
Explanation: In those locations where there is little to no atmosphere (like moon or Mercury), drag is not a reliable factor for slowing down the rocket. Reverse thrust is usually employed in such cases for the same purpose during the descent and the touchdown
10 - Question
Which of the following terms doesn’t relate to docking?
a) Lock-on
b) Rendezvous maneuver
c) Spacecrafts
d) Heat shield
View Answer
Explanation: Docking is the process in which two spacecrafts gradually approach each other and link together. It is a kind of rendezvous maneuver involving pulse node thrusters and low thrust. It is sometimes called lock-on.