CBT - Bleed

Question 1

When do the LP and HP compressor stages supply bleed air?

Answer 1

LP always supplies and HP will supply at low thrust settings as LP will not be enough

Question 2

What is the box just ahead of the engines ?

Answer 2

Bleed air precooler outlet temperature and inlet pressure

Question 3

When engine bleed and APU bleed are on, which takes precedence?

Answer 3

APU bleed will always have priority when on and will shut off engine bleed valves in certain flight conditions

When altitude is below 22500 and speed below Mach 0.56

Question 4

What happens if apu bleed is used with xbleed selector on closed?

Answer 4

Only pack one is served

Question 5

How is bleed leak detected and how is it managed?

Answer 5

2 Bleed Leak Detection systems (1 &2) that utilize many loops (APU, Air Con, Inner/outer wings, engine and pack bay)
On detection of a leak they will close the applicable X Bleed valves and open unaffected ones

Question 6

What is bleed source is also lost if a leak has been detected on engine 1?

Answer 6

APU bleed is also lost