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New performance PNR fuel requirements (Part 91) - help please!

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Jay created the topic: New performance PNR fuel requirements (Part 91) - help please!

Hi all (happy new year and merry xmas),

I just want to clarify, when calculating a PNR I need to know the safe endurance, previously the FR was 45mins FR for RPT and Charter, 30 mins for normal day VFR (private etc).

I was looking at the (possibly) new part 91 fuel requirements AC 91-15v1.1 and it doesn't seem to mention any difference from normal day VFR from RPT/Charter - so does this mean the only requirement is the normal 30mins FR (unless the question states differently)?

It also states that you have to have "fuel to fly for 15 mins at the holding speed for the aircraft at 1 500 ft above the aerodrome elevation in ISA conditions" - is this something I also have to take into account and add on regardless, or it's dependent of the question?

Old study material I have states taxi 3 gal & 15 gal for FR - would this to be expected or is it more likely that I'll have to work this out for myself in an exam scenario.

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MissSoph replied the topic: New performance PNR fuel requirements (Part 91) - help please!

Hey jay…. :() can’t believe they decide to Change it all on us …ahhhhhh….so is there no difference now between private, charter, RPT? Also have you been able to see if there are amendments available yet? I just had a look on the Airservices store and can’t see any yet for the CAAP….
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Bosi72 replied the topic: New performance PNR fuel requirements (Part 91) - help please!

Paragraph 4.4.2 from AC 91-15v1.1
a couple of lines above your screenshot says:
Because of the varying nature of the operations, the amounts of fuel mentioned below do not apply to air transport operations. Air transport operators must comply with the requirements of Parts 121, 133 or 135 of CASR, as applicable.

Regarding 1500ft definition, the same was in old Caap 234-1.



I'd say business as usual, just terminology changed.
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Jay replied the topic: New performance PNR fuel requirements (Part 91) - help please!

Hi Bosi72 - OK so it seems fair to say to ignore the 15min holding time but just to clarify, previous work examples had a 15% FR for CPL performance - unless stated otherwise do we now ignore it and go with the fuel allowances I put in the attachment (30mins)?

For example previous scenarios where startup 180 gal, fuel flow 28gal/hr, FR 3 gal for taxi and 15 gal for flight.

So then there was 180 - 3 - 15 = 162 gal, then that was apparently 115% of flight fuel so to calculate safe endurance / by 1.15 giving a safe endurance of 141 gal.

Do I now ignore this / by 1.15?
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Bosi72 replied the topic: New performance PNR fuel requirements (Part 91) - help please!

Hi Jay
I can't find original question that you are trying to solve. However, 15% variable reserve was changed to 10% in ~2018 by CAAP 234-1. I studied and practiced from old performance book with 15% reserves everywhere, however at the exam I used 10% as per latest regulations at the time.

Regardless, before answering any fuel questions you need to know what type of operation is your aircraft flying:
If it's Part 91, then you use the fuel figures from AC 91-15v1.1.
If it's Part 135 (air transport) you will need to use fuel figures from Chapter 7 from CASR Part 135 MOS.

Have a look at Bob Tait New IREX Extract pdf, page 79, paragraph 7.02, under definition of contingency fuel. It says 10% or 5min.

Further down next page, table final reserve specifies 45mins for piston and 30min for turbine aircrafts.

So if your aircraft is air transport (formerly known as rpt/cht) you will need to divide by /1.1

I believe at the exam you will be told whether your aircraft is flying Part 91 or Part 135

Hope this helps
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Jay replied the topic: New performance PNR fuel requirements (Part 91) - help please!

Thanks for the reply and your help. OK fuuuun. I just had a look at the permitted material for the Performance Exam, so it could be either / or.

I don't want to get confused with IREX (45mins) or ATPL stuff, they may/are different fuel requirements, just for CPL below 5700kg.

So like you said, just to clarify - Part 91 is just 30mins and Part 135 is 10% or 5mins, whichever is greater?

This is what CASA has for their Airservices list:
Part 91 of CASR and Part 91 MOS

Part 135 of CASR and Part 135 MOS

AC 91-02

AIP Book

ERSA complete

Navigation equipment

A basic calculator
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Bosi72 replied the topic: New performance PNR fuel requirements (Part 91) - help please!

I only pointed to Irex extract because I looked it the other day and it was easier to find Chapter 7 of Part 135.


>So like you said, just to clarify - Part
> 91 is just 30mins and Part 135 is
> 10% or 5mins, whichever is greater?

Yes, that's how I read from the current law regulations.

In any case get familiar with all permitted material that you bring into exam.
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Bosi72 replied the topic: New performance PNR fuel requirements (Part 91) - help please!

Jay wrote:
I don't want to get confused with IREX (45mins) or ATPL stuff, they may/are different fuel requirements, just for CPL below 5700kg.


I think you need to clarify this: Part 135 is not about IREX nor ATPL. It is about Air Transport.
Therefore Final reserve for any Piston aircraft flying Part 135 is 45mins (as per table), plus 10%/5min for Contingency fuel.

Also don't forget there are turbine aircrafts below 3500kg that you can fly passengers commercially with CPL (eg. Cessna 206 turbine). In that case Final reserve for any Turbine aircraft flying Part 135 is 30mins (as per table), plus 10%/5min for Contingency fuel.
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Jay replied the topic: New performance PNR fuel requirements (Part 91) - help please!

Hi

From my understanding the exam doesn't go into detail of weight / turbine for different fuel requirements etc etc, just a normal piston aircraft <5700kg. Just for the sake of the subject that's why I was trying to avoid IREX / ATPL discussion (and to limit my own brain going into meltdown ha!) & differences with their fuel allowances, but I appreciate your points.

That's right I think I confused myself there again, Part 135 is 45mins + 10%/5min - (I quickly glanced at an old text and it was 15% so I think I was getting muddled up with that too).
Part 91 is just the 30mins.

CASA would have to really elaborate if they were to mention an aircraft like a 206 but historically they keep it a bit more simple (rare I can say that), I'd imagine.

It seems people sitting this exam prior to December 2nd had one less fuel scenario to worry about & now we have two.
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Stuart Tait replied the topic: New performance PNR fuel requirements (Part 91) - help please!

You are correct about having two scenarios although CASA says it's going to be very clear on the difference.

We will see, but as always Read the Question.

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