250+ TOP MCQs on Engine Design and Answers

Rocket Propulsion Multiple Choice Questions on “Engine Design”.

1. Which of the following studies usually result in a small improvement in vehicle performance?
a) Optimization studies
b) Mission analysis
c) Trajectory design
d) Launch site selection
Answer: a
Clarification: Optimization studies lead to small improvements in vehicle performance. This process is sometimes completed even before identifying a suitable engine.

2. Which of the following is not optimized in the optimization studies?
a) Mission duration
b) Chamber pressure
c) Nozzle area ratio
d) Thrust
Answer: a
Clarification: Chamber pressure, nozzle area ratio, thrust, mixture ratio etc are optimized in the optimization studies. It results in small improvements in propellant fraction, engine volume, cost and vehicle performance.

3. Which of the following primarily involves obtaining data from prior similar engines?
a) Preliminary engine performance estimates
b) Optimization studies
c) Testing of full scale models
d) Small scale modeling
Answer: a
Clarification: Preliminary engine performance estimates involves obtaining data from existing similar models. When they are not readily available, then theoretical performance values calculated by incorporating correction factors, experimentation or simulation methods are adapted.

4. Which of the following is not a recommended source for arriving at a tentative decision about the engine to be made?
a) Mission requirements
b) Customer preferences
c) Past experiences
d) Full-fledged simulations
Answer: d
Clarification: Since the decisions to be made are tentative, a full-fledged simulation will most likely result in a waste of time and resources. Making logical decisions backed by mission requirements, customer preferences and past experiences is more sensible approach.

5. __________ generally do not take technical decisions on behalf of the rocket engine design.
a) Manufacturing experts
b) Field service experts
c) Stress analysis experts
d) Consultancy experts
Answer: d
Clarification: Experts from the fields of manufacturing, stress analysis, field service and safety are important in making appropriate decisions on behalf of the rocket engine design.

6. Key engine selection decisions are validated later in ___________ process by __________
a) deployment; testing new components and engines
b) development; testing new components and engines
c) preliminary stage; proposing new components and engines based on existing knowledge
d) mission analysis; proposing new components and engines based on existing knowledge
Answer: b
Clarification: The engine selection decisions are validated in the development stage. In the development stage, new components and new engines are tested.

7. Which of the following are key parameters of interest for the vehicle designer?
a) Both Inert mass and center of gravity
b) Inert mass, but not center of gravity
c) Center of gravity, but not inert mass
d) Neither center of gravity nor inert mass
Answer: a
Clarification: Both inert mass of the engine and other mass properties like center of gravity or moment of inertia are key parameters to the customer as well as the vehicle designer. They are used both in the preliminary and final design.

8. _________ balances the pressure drops in fuel, oxidizer and pressurizing gas flow systems.
a) Performance balance program
b) Engine balance program
c) Optimization program
d) Fuel balance program
Answer: b
Clarification: Engine balance program balances the pressure drops in oxidizer and fuel. It also balances pressurizing gas flow systems. It is a kind of computer program that specifically operates on a particular engine cycle.

9. _________ is not a type of engine by the degree of novelty.
a) New engine with new major components and new design
b) New engine with major components from existing engines.
c) Updated or improved version of a proven engine
d) Reuse of a decommissioned engine
Answer: d
Clarification: Reuse of a decommissioned engine isn’t part of the degree of novelty. It doesn’t involve any new design procedure and it is not recommended.

10. What is the simulation of the steady-state, internal conditions and functioning of the engine called?
a) Power balance
b) Optimization
c) Engine balance
d) Engine equilibrium
Answer: a
Clarification: A power balance is a simulation of the steady-state, internal conditions and functioning of an engine. It may require varying levels of complexity to model a power balance, ranging from the use of a simple spreadsheet to the use of complicated computer programs.