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## CPL final Question 37

• Topic Author

### Madox01 created the topic: CPL final Question 37

The Question states:

An Echo has 300litres of fuel on board at start up. If the flight fuel required is 120litres, how long could the aeroplane plan to hold at the destination aerodrome if holding is set at 35% MCP?

35%MCP = 17.2gph
300litres/3.8 = 79gals
FF = 120/3.8= 32gals

my working is as follows

(79-3-15)/1.15=53gals
FF=32gals
Remaining=53-32=This email address is being protected from spambots. You need JavaScript enabled to view it.= 75minutes

32*1.15+15+3=55gals
Remainding=79-55=This email address is being protected from spambots. You need JavaScript enabled to view it.= 84minutes

Both are very similar answers and could cause problems in the exam.

Should i always multiply the variable reserve and add all reserves/taxi to the flight fuel then subtract that total from the fuel on board at start up?

The exam is soon and i feel it will be pretty tough so Im just hoping to receive some feedback from someone with regards to what method i should use?

Cheers!

• Posts: 1914

### bobtait replied the topic: Re: CPL final Question 37

In your working you have allowed for 15% of the total fuel on board [79 gals]. You only need to carry 15% of the flight fuel. So:
Minimum fuel required is 32 x 1.15 + 15 + 3 = 55 gals.
Fuel available = 79 gals.
Fuel available for holding = 24 gals.
@ 17.2 gph = 84 minutes.

• Topic Author

### Madox01 replied the topic: Re: CPL final Question 37

Thanks bob, totally understand now

I totally forgot that the holding fuel due to being over destination doesn't require the 15% variable reserve

Guess I'm just stressing because the big day is tomorrow

Thankyou