ATPL Flight Planning Holding Fuel Query

[Mattoosular]

Hi,

I have my ATPL Flight planning exam on Monday (my last ATPL....finally). Self studied... regrettably.

Basically, I seem to do quite well in the practice exams (Rob Avery), but the only area that seems to let me down is acceptable/suitable/inter/tempo considerations. I understand WIP and Traffic. Could someone confirm that the following is correct?

For ETP, normal needs holding fuel for whatever is required at destination. Depressurization doesn't require any holding at all, One engine inoperative requires weather only holding (inter/ tempo) at either the destination or departure airport - what ever is worse.

For PNR, Depress is same, but normal and ENG INOP requires holding fuel which only considers the airport the aircraft plans to turn around to (and again, INOP doesnt require traffic or WIP under and circumstances)....? It's the last paragraph that I'm confused about :S

Eg, Going Alice to Bris, working out PNR for Mt Isa, so if Mt Isa has INTER and Bris has TEMPO, you only need INTER holding fuel?

Thanks for your help!

[AerodyManic]

Hi matto,
I recently did flight planning (passed thankfully). Without my 727 manual handy I can't tell you for sure. However there is a page in there somewhere that will tell you the answer to your question. From memory it is near page 1-17. If I can give you some sound advice (as given to me from my FP tutor) it would to read that manual from cover to cover and makes sure you know all the little clauses and twists that CASA will try to get you on in the exam. Also if you can, really brush up on fuel policy. Knowing how to do a five mark question is great, but if you start off with the wrong fuel figures, you have just wasted 15 minutes and will probably get it wrong. (CASA will undoubtedly provide an answer for those wrongly calculated fuel policies):ugh:
I'll do my best to find the answer for you when I get back.

Good luck ;)

[mugzy]

It is calculated on the basis that you have flown normal ops out to your PNR then back with the abnormality ( 1-INOP or DP ) and the reserves intact.

You need to allow for the holding fuel at the aerodrome you are returning to. The holding fuel required at your destination is no longer relevant...

[Lasiorhinus]

In an emergency, you can consider ATC will give you traffic priority, so you do not need to plan for traffic holding fuel. You may still be held up with weather, so in most cases you'll need weather holding fuel even with priority.

If your flight is Alice -> Isa -> Brisbane, and you are calculating a PNR for the Alice -> Isa segment, then you need only take into account Tempo/Inter at Alice and Isa. Brisbane is irrelevant.
Say Alice has a Tempo, and Isa has a Inter. You'd take the 30 mins, because if the engine failure/depressurisation happened at the PNR, you'd plan to go to Isa, due to less holding time required. If the failure happened anywhere else, you go wherever is closer.

There is a confusing segment of the flight in the few minutes prior to reaching your PNR in which you'd technically be closer to Alice and therefore should plan to return there, but only held 30 mins holiding fuel instead of 60.
Ignore this - CASA do too.

[Cessna 180]

I am unfortunately reading up on this subject at the moment too and they way I read it is that once you are d-p the weather holding requirements just vanish. Not sure how that would happen, buy anyway.
Would also appreciate a bit of guidance on this.
Ta.

[Mattoosular]

Thank you very much for your posts (quite prompt I might add). Answered my question perfectly. Can anyone answer Cessna 180 (http://www.pprune.org/members/328569-cessna-180)'s question though? I don't quite understand why depressurized ops don't require weather holding... Obviously the weather doesn't really care if you're depressurized or not :) But I'm sure there's a logical reason to it.

Oh, one last thing to add which I'm not completely sure about. Do 'gear down', 'tailskid down' and 'yaw damper failure' ops require traffic and WIP holding fuel? I assume in reality ATC would prioritise them considering the significant fuel burn increase, but I haven't successfully found an explanation for this in my text book...

[Lasiorhinus]

I dont have my 727 book handy at the moment, but YD and tailskid down holding fuel flows aren't any different to normal ops holding fuel flows.

Off the top of my head I think gear down would be higher, but I'll have to check this when i get home.

[Mattoosular]

Oh yeah I understand that - I think it's +50% landing gear down and perhaps 25% for tail skid (need book), but I'm not sure if Work in progress/Traffic holding fuel is actually required at all in the situations, well, for the exam anyway.