Hi All,

I will be sitting my first attempt at performance exam next Tuesday 26th July 2011 in Sydney, I have came across question asking for MAX Range achieved out of the following:

TAS - 153 Knots
Fuel Flow - 20.4 gal p/h
Usable fuel - 150 US gal
Wind component - 25kt Tailwind
Fixed reserve 15 gallons

All above are based on Echo.

Given Answers are: 1000nm , 1024nm , 1050nm and 1075nm

What I have done:
I have subtracted fixed reserve from usable fuel as fixed reserve needs to be intact at arrival.

Therefore: 150-15=135 gal usable

Then, I used the following formula:

Fuel Capacity / Fuel Flow x TAS (135/20.4x153 = 1012nm)

Any ideas would be much helpful.

Given Answers are : 1000nm , 1024nm , 1050nm and 1075nm

What I have done:
I have subtracted fixed reserve from usuable fuel as fixed reserver needs to be intact at arrival.

therefore: 150-15=135 gal usable

then, I used the following formula:

Fuel Capacitiy / Fuel Flow x TAS (135/20.4x153 = 1012nm)

Any ideas would be much helpful.

hey mate did you allow for the 15% variable cos i think ive seen this questions i got performance tommorow so ill give you a few heads up on what to look out for cheers

Two things you may have missed. If it is a charter flight and I suspect it is, you would also have to account for the variable reserve. So flight fuel available would be 150-15 /1.15 = 117.39 gal. Also, you have not allowed for the wind. So the ground speed would be 153+25 = 178kt.

The working then becomes: 117.39/20.4 x 178 = 1024nm.

Thanks all, I am beating most echo will be in Casa exams but hopefully won't be difficult and to confusing like aerodynamics