Powerplant

Question 1

how does pressure vary within the combustion chamber of a gas turbine

Answer 1

Theoretically pressure is constant, though in reality a drop of 3-6% is usual

Question 2

What is Boyles Law

Answer 2

P*V = K

Question 3

What is Charles’ Law?

Answer 3

V/T = K

Question 4

What is the Combined Gas Law?

Answer 4

(P*V)/T = K

Question 5

What is ESHP

Answer 5

Equivalent Shaft Horsepower, equal to Turbine Shaft Horsepower + residual jet thrust

Question 6

At what temperatures might inlet icing occour?

Answer 6

below +10 degrees c

Question 7

What is the typical compression ratio of a singe stage of an axial compressor?

Answer 7

1.1/1.2 to 1

Question 8

What is the typical compression ratio of a centrifugal compressor?

Answer 8

4 to 1

Question 9

What is the speed of gases in a jet pipe?

Answer 9

Mach 0.5

Question 10

1 Shaft Horsepower (shp) is roughly equivalent to how many pounds of thrust?

Answer 10

2.5 pounds of thrust

Question 11

At engine idle, what is the typical speed of the LP compressor of a turbofan engine

Answer 11

25%

Question 12

At engine idle, what is the typical speed of the HP compressor of a turbofan engine

Answer 12

50-60%

Question 13

At engine idle, what is the typical thrust produced by a turbofan as a percentage of take-off thrust?

Answer 13

5%

Question 14

What is the energy output of a turbine ignition system set to high energy?

Answer 14

6-12 joules

Question 15

What is the energy output of a turbine ignition system set to low energy?

Answer 15

3-6 joules

Question 16

What does HEIU stand for?

Answer 16

High Energy Ignition Unit

Question 17

What is the voltage typically required in an old style turbine spark plug

Answer 17

25,000 Volts

Question 18

What is the voltage typically required in a surface discharge igniter plug?

Answer 18

2,000 volts

Question 19

what is the rate of discharge of a High Energy ignition Unit?

Answer 19

60 - 100 discharges per minute

Question 20

At what speed does a jet engine become self sustaining?

Answer 20

30% N2 (HP compressor)

Question 21

Between what temperatures can icing occour in the induction systems of a piston engine

Answer 21

-7 to +33 degrees C

Question 22

What, roughly, is the maximum deceleration of a braking plane

Answer 22

on the order of 6m/s/s. above this value brake pressure is automatically reduced

Question 23

at what speed is the brake anti-skid system deactivated?

Answer 23

20 mph

Question 24

In RTO (Rejected Take off) mode, at what speed do the autobrakes arm

Answer 24

85 knots

Question 25

At what speed does the autobrake system normally disarm

Answer 25

20 knots

Question 26

at what speed is the brake anti-lock system deactivated?

Answer 26

10 mph, though on some aircraft they are never disarmed.

Question 27

What are the four regions of a tyre

Answer 27

from outer to inner: crown, shoulder, sidewall, bead

Question 28

what is the inflation pressure of a low pressure tyre?

Answer 28

23 - 35 psi

Question 29

what is the inflation pressure of a medium pressure tyre?

Answer 29

35 - 70 psi

Question 30

what is the inflation pressure of a high pressure tyre?

Answer 30

70 - 90 psi

Question 31

what is the inflation pressure of an extra high pressure tyre?

Answer 31

more than 90 psi (350 psi is typical of a large airliner)