15.3 Inlet

Question 1

What do engines use to straighten airflow in to the compressor inlet?

Answer 1

Inlet/ inlet guide vanes

Question 2

What kind of part is the air inlet duct?

Answer 2

Airframe part not a part of the engine

Question 3

What type of engines consume more airflow and so what is more critical?

Answer 3

Gas turbine engines
Air emergence passage is more critical especially at high speeds

Question 4

What aircraft usually have screens to cover the inlet for prevention of FOD?

Answer 4

turboprop and turboshaft engines

Question 5

How is pressure recovered when thrust decreases as the aircraft speed increases?

Answer 5

• ram recovery
• the inlet compresses free airstream molecules to recover pressure

Question 6

What is air pressure drop in the engine inlet caused by?

Answer 6

• friction of air along both sides of the duct
• by bends in the duct system

Question 7

What’s accomplished by turning the airflow on engines with low flow rates?

Answer 7

Engine nacelle can be smaller
Less drag

Question 8

What must the duct in turbofan engines have?

Answer 8

Straight section for smooth airflow during high airflows

Question 9

How is the configuration of the entrance duct decided?

Answer 9

• location of the engine on the aircraft
• airspeed, altitude and attitude It’s designed to operate at

Question 10

What are the two types of divided duct?

Answer 10

Wing- root inlet or a scoop at either side