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##### A preview of the upcoming Video Lecture Series (14 Mar 2019)

This video is a snippet of the third day of the IREX course and it covers the Provision of Alternates

vimeo.com/323619910/90d43d366c

× Welcome to the CPL Performance question and answer forum. Please feel free to post your questions but more importantly also suggest answers for your forum colleagues. Bob himself or one of the other tutors will get to your question as soon as we can.

## Alternate Fuel issues

• Posts: 17

### Kaos created the topic: Alternate Fuel issues

Howdy,

I've been working through the performance book, sitting the exam next week.

On page 102 you're asking for minimum fuel calculations. As per the new CAAP - variable fuel is trip fuel only (it does not include alternate). I take this to mean that we multiply our trip fuel by 1.1 (10% variable) then add the Alternate. Is my interpretation incorrect or has this just been overlooked? It changes some answers by several gallons. CASA have you manually type in many answers now and they won't tell us the tolerances, if we don't get these calculations correct I think it'll be the difference between pass/failing those questions.

Also, you have updated answers to include the new CAAP (question 9/10 on page 98) but it still states 45 mins Fixed reserve when it should be 30 mins

Cheers!

• Posts: 245

### Stuart Tait replied the topic: Alternate Fuel issues

G'day Kaos

Your interpretation is incorrect, flight fuel = (departure to destination and on to the alternate) x 1.1 + holding + taxi*
*(depending on the question).

EDIT: Flight fuel is no longer used it is now trip fuel and the variable reserve only applies to trip fuel as such the calculation is now
[Trip fuel] x 1.1 + Alternate fuel + Holding Fuel + Taxi fuel (depending on the question)

Page 98 question 10 you are correct it should be 30 minutes as it's a private flight

I'll change the question to reflect that

Cheers

• Posts: 17

### Kaos replied the topic: Alternate Fuel issues

Cheers for the quick response. Also while I remember, the link in the new performance e-text is for the old CAAP not 234 (2)

In the definitions of the new CAAP (copied below) it gives the definition for Trip Fuel (not Flight fuel anymore) and Variable. The note at the bottom of Variable states it does not apply to alternate fuel?

The amount of fuel required to enable the aircraft to fly until landing at the destination aerodrome, taking into account the operating conditions in paragraph 3.3. This includes (as applicable):
a. fuel for take-off and climb from departure aerodrome elevation to initial cruising level/altitude, taking into account the expected departure routing, and
b. fuel for cruise from top of climb to top of descent, including any step climb/descent, and
c. fuel from top of descent to the point where the approach is initiated,taking into account the expected arrival procedure, and
d. fuel for conducting an approach and landing at the destination aerodrome.

Variable fuel reserve The amount of fuel required to compensate for unforeseen factors. It shall be the highest of the percentage of the planned trip fuel specified in column 4 of Table 1 for the applicable category and class of aircraft or, in the event of inflight re-planning, the percentage specified in column 4 of Table 1 for the trip fuel from the point of in-flight re-planning, or the fuel required to fly for 5 minutes at holding speed at 1,500 ft above the destination aerodrome elevation in ISA conditions (as applicable).
Note: Variable fuel reserve does not apply to alternate fuel.

• Posts: 53

### lucasgozzard replied the topic: Alternate Fuel issues

If you look at the sample fuel calc annexes, they work out variable fuel reserve based on trip fuel not trip + alternate.

• Posts: 245

### Stuart Tait replied the topic: Alternate Fuel issues

G'day Kaos

You have a point there we didn't catch that change in the CAAP we have emailed CASA and will report back with our findings.

I guess you don't ever have unforeseen headwinds when going to an alternate anymore CASA must have done a deal with God.

Cheers

• Posts: 53

### lucasgozzard replied the topic: Alternate Fuel issues

Hahah feel sorry for you and the team Stuart! You've probably already changed most of the textbook and online course and exam questions have you?

• Posts: 245

Never ends Lucas

• Posts: 53

• Posts: 17

### Kaos replied the topic: Alternate Fuel issues

Thank you! Thought I was going crazy for a second there!! Appreciate the follow up

Always fun learning about the 'interesting' choices CASA makes for us