Engine Start

Question 1

What are the 2 pneumatic sources for engine start?

Answer 1

APU and Engine Crossbleed

Question 2

What are the positions of the AIR SOURCE ECS/START switch?

Answer 2

APU BOOST - air from APU
OFF
ENG - Air from either engine

Question 3

What is the purpose of the AIR SOURCE ECS/START switch?

Answer 3

Selects the source of air pressure for engine starts and ECS operation

Question 4

What happens when the starter button is depressed?

Answer 4

Starter is engages, air is provided from selected source

Anti-ice start/bleed valve stays open until Ng reaches 90/94% (OAT) to prevent compressor stall by reducing backpressure

Question 5

What does the alternator provide?

Answer 5

Gives power to the ignition exciter and will dropout 52-65% Ng

Question 6

How can you disengage a starter if it fails to dropout? (3)

Answer 6

• Pull down on starter
• Pull CB
• AIR SOURCE ECS/START to OFF

Question 7

How can you override a faulty starter?

Answer 7

• Manually hold in starter button until 52-65% Ng

Question 8

APU Start

Answer 8

APU will provide pneumatic power to start engines regardless of AIR SOURCE ECS/START switch position

Question 9

Crossbleed Start

Answer 9

Ng on receiving engine shall be 24% minimum before PCL advance to IDLE and donor engine will require 90-94% Ng