Leap-1A - 76 & 77

Question 1

Where is the N1 speed sensor wheel?

Answer 1

Rear of the No. 2 bearing

Question 2

On the N1 phonic wheel, how is angular position measurement achieved?

Answer 2

Single low tooth

Question 3

To what module of the engine are the EGT probes fitted?

Answer 3

Turbine Centre Frame (TCF)

Question 4

Which EGT probes are used for channel A?

Answer 4

1, 6, 7, 8

Question 5

How many EGT sensors are required to calculate an EGT value?

Answer 5

Only one per channel

Question 6

What is the purpose of the Core Compartment Temperature (CCT) sensor?

Answer 6

Senses and transmits the under cowl temperature to enable air leak detection in the air ducts and air valves

Question 7

Where is the CCT located?

Answer 7

At the 3 o’clock position between the 4th and 10th stage bleed ducts

Question 8

What is the redline limit of N1?

Answer 8

101%

Question 9

What do amber crosses in the N1 indication mean?

Answer 9

Invalid N1 signal - The EEC is unable to synthesise the value from other engine parameters

Question 10

What do amber dashes in the N1 indication mean?

Answer 10

Failure of both N1 probes or loss of signals - The EEC is able to synthesise the value from other engine parameters

Question 11

What is the redline limit of N2?

Answer 11

116.5%

Question 12

When will you receive a steady amber indication concerning oil temperature?

Answer 12

1. First oil temperature threshold (135°C) for more than 15 minutes
2. Exceeds second oil temperature threshold (150°C) for more than 5 seconds

Question 13

When will vibration levels indicate steady amber?

Answer 13

N1 - 6.0 CU (cockpit units)
N2 - 4.25 CU

Question 14

When will nacelle temperatures be displayed and pulsing green?

Answer 14

Will be displayed when nacelle temperature advisory display has been triggered on one engine

> 280°C