Question

To improve IR detection of engine, we can ____________

(a) hide the nozzle from expected location of an IR sensor

(b) use higher exhaust temperature

(c) show nozzle at IR sensor

(d) nozzle does not affect the IR detection

I have been asked this question during an internship interview.

My question is from Configuration Layout Considerations topic in chapter Configuration Layout Considerations of Aircraft Design

Answer 1

The correct answer is (a) hide the nozzle from expected location of an IR sensor

Easiest explanation: Emissions of hot parts can be reduced by lowering their temperature. We can hide nozzle from the IR detector itself. As a result we can improve the IR detectability.