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## Fuel Reserves

• Andrewy
• Topic Author

### Andrewy created the topic: Fuel Reserves

Hello all,

This may be a bit of a stupid question, but I'll ask it anyway.

Lets say you are calculating the safe endurance for a PNR or something for a flight between two points, and are given the total fuel at startup as well as the distance between both points.
Do you calculate the 15% reserve from the fuel required to fly from point A to B, or from the total fuel available minus the fixed reserves/taxi etc?

Performance is my last exam and I just want to be sure on everything.

Cheers,
Andrew

• Posts: 1914

### bobtait replied the topic: Re: Fuel Reserves

Andrew

A PNR really has nothing to do with the destination aerodrome. It doesn't matter where you are planning on going. The PNR is simply the point in a given direction from which it would be impossible to return to the departure aerodrome with all reserves intact. If you had a lot of extra fuel at start-up, it wouldn't be impossible for the PNR to be beyond the destination!! In that case, of course, there would effectively be no PNR for that flight. When you calculate the PNR you consider only the total flight fuel available. That is TOTAL FUEL - TAXI - FIXED RESERVE Ã· 1.15.

Bob

• Andrewy
• Topic Author

### Andrewy replied the topic: Re: Fuel Reserves

I've got the exam tomorrow so hopefully I should be fine.

Just on an unrelated side note, I know that the Echo is fictional, but is there a type of aircraft it closely resembles? ie If I open the POH to that aircraft, I'd find all the performance data matches the Echo.