M15.3 Inlets

Question 1

What type of duct is a air inlet

Answer 1

Divergent

Question 2

What does a divergent duct do

Answer 2

Increase air pressure

Question 3

Parts of the inlet

Answer 3

Inlet duct
Inlet nose

Question 4

What causes if disturbances in a air intake

Answer 4

• Damage
• Ice
• Crosswind

Question 5

When is there no ram air effect

Answer 5

Aircraft is not moving

Question 6

What happens when there is no ram air into an engine

Answer 6

Air gets pulled from the sides

Question 7

What indicates the danger zone on a running engine

Answer 7

Red stripe

Question 8

What is the ideal airspeed for air hitting the compressor

Answer 8

0.4-0.7 Mach

Question 9

How is the risk of air separation in the inlet reduced

Answer 9

The lip is rounded

Question 10

Which speeds is a pitot type intake designed to take

Answer 10

Up to 1.5 Mach

Question 11

What is the inlet critical condition

Answer 11

Max airflow at rates Mach altitude

Question 12

Supersonic shock wave types

Answer 12

• Normal
• Oblique
• Bow

Question 13

When and how do normal shockwaves form

Answer 13

• Low supersonic speeds perpendicular to the airflow

Question 14

What happens to airspeed in a normal shock wave

Answer 14

Supersonic to subsonic

Question 15

What determines the angle of an oblique shock wave

Answer 15

The upstream velocity

Question 16

Main difference between bow wave and oblique wave

Answer 16

Bow wave is detached

Question 17

In supersonic ducts how is the buzz effect overcome

Answer 17

Variable geometry air intake

Question 18

When can a normal shock diffuser inlet be used

Answer 18

Low supersonic speeds

Question 19

How many shock waves are employed in a variable geometry air inlet duct

Answer 19

Three oblique, one normal

Question 20

In a variable geometry air inlet, what is used at high speeds to prevent intake buzz

Answer 20

Bleed door

Question 21

What type of valve is used in thermal engine anti-ice systems

Answer 21

Solenoid controlled pressure regulated valves

Question 22

What closes the solenoid controlled valves

Answer 22

Spring force

Question 23

What monitors the pressure regulating valves

Answer 23

Two pressure switches

Question 24

What are the pressure switches found in thermal anti-icing

Answer 24

Downstream of the valve

Question 25

Ice protection cyclic sequence - typical cycles

Answer 25

Fast - 2 minutes - OAT -6 to 10c

Slow - 6 minutes - OAT Below -6c