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## PNR ENDURANCE

• Posts: 1

### Hossain created the topic: PNR ENDURANCE

Hi,
Some help would be very appreciated with PNR endurance.
With the new CAAP. For PNR endurance calculation what do we use ?
TRIP FUEL = Endurance ?
Also Safe Endurance is TripFuel + Variable reserve ?

Please some clearification would really help thanks.

• Posts: 1902

### bobtait replied the topic: PNR ENDURANCE

Two things have changed. What used to be called 'flight fuel' is now called 'trip fuel'. For general aviation aircraft, there is no difference except the name change.

Variable reserve is now 10% of trip fuel instead of 15%.

Save endurance does not include any reserves and it never has. So trip fuel is total fuel minus ALL reserves.

SAFE ENDURANCE
= (TOTAL FUEL AT TAKE-OFF - FIXED RESERVE - TAXI ALLOWANCE - MINUS DEPARTURE POINT HOLDING) ÷ 1.1
Dividing by 1.1 removes the 10% variable reserve. Answer expressed in minutes.
The following user(s) said Thank You: sean1390, Hossain, Flyboi

• Posts: 1

### Flyboi replied the topic: PNR ENDURANCE

Thanks for the clarification, Bob.

While on the subject of PNR and safe endurance, given the November 8 2018 CAAP 234-1(2) changes, is ALTERNATE FUEL included as TRIP FUEL for Safe Endurance now, but not subject to the 10% variable reserve (assuming RPT/Charter)?

I tried explaining to a friend and I hope the following is correct?

"so say you have 180 L total and your burn is 25 Lph, and you have an alternate that requires 20 L. You want to find safe endurance, so

180 L total
- 19 L Fixed reserve (45 mins)
- 5 L taxi/startup
- 20 L alternate fuel
= 136 L

Now you need to take away the variable reserve, so
136 L / 1.10%
= 124 L

BUT trip fuel for safe endurance includes any alternate fuel so,
124 L + 20 L alternate fuel
=144 L

144 L @ 25 Lph = 345 minutes safe endurance"

Clarification on this post-fuel mayhem would be greatly appreciated

-every CPL candidate about to sit performance
The following user(s) said Thank You: Hossain

• Posts: 260

### Stuart Tait replied the topic: PNR ENDURANCE

G'day flyboi

What you have outlined there is correct

Cheers
The following user(s) said Thank You: Hossain, Flyboi