PPRuNe Forums

PPRuNe Forums (https://www.pprune.org/)
-   Questions (https://www.pprune.org/questions-67/)
-   -   Fuel for APU ops (https://www.pprune.org/questions/540501-fuel-apu-ops.html)

George Yogi 26th May 2014 17:09

Fuel for APU ops
 
1.For an A320 a/c according to FCOM , Fuel burn for APU is 130 kg/ hr ..
Where do pilot accommodate this fuel for an a/c which is ready for Operation
Is it accommodated in Ramp fuel ? or extra fuel ?

2.In Air crash investigation series , I have seen when one engine fails , Pilot
switch on APU to supply the Bleed.Does the fuel for the APU in this case supplied from failed engines tank using cross feed valves ?

de facto 26th May 2014 17:18

Forgot the magic word?:E

Intruder 26th May 2014 17:52

What are your company procedures? How long do you normally have from end of fueling to block-out? What does your Dispatch Release say? What does your ground school instructor say?

Block fuel is generally that fuel required on block-out. The final fuel load will have to consider any fuel use prior to block-out.

gAMbl3 26th May 2014 17:55

APU fuel will be part of Taxi fuel and quantity is as per your company OPS manual.

In case of engine failure is it better to start APU so that bleed is extracted from it, which other wise would have been extracted from live engine and performance would have been reduced. Left fuel feed line supplies APU. If the Left side pumps are not working then APU fuel pump starts automatically. Fuel X feed may be selected on to take care of fuel imbalance only when there is no fuel leak.

Meikleour 26th May 2014 19:24

Yogi: your profile claims that you fly the A320...............!!!!!!

I-WEBA 28th May 2014 06:18

Just a curiosity, as I am not a pilot, only an aircraft lover.

In most of the Italian airports boarding can start only after completing refuelling. Usually boarding takes from 10 to 20 mins on A320, in this case do you board extra fuel for APU use?

Kind regards

Intruder 28th May 2014 17:40

Yes, though generally the overflow after the airplane fuel system signals for shutoff of the refueler will be enough for a short APU run. Even the APU on a 744 only burns 300 Kg/hour...

flyboyike 1st Jun 2014 20:51


Originally Posted by Intruder
Yes, though generally the overflow after the airplane fuel system signals for shutoff of the refueler will be enough for a short APU run.

One more time, in English.

Piltdown Man 2nd Jun 2014 12:35

1. As APU fuel is normally included as part if the taxi fuel, it would be part of Ramp or Block Fuel. Extra fuel is exactly what it says on the tin. Fuel that is in excess of everything that is planned to be burnt.

2. The most important function of the APU following an engine failure in a twin is to provide an additional generator, not bleed air. It's fuel will be supplied from whatever source is available.

And referring to my comment in an additional thread, you really need to get some more (lots more) time in aircraft, preferably under supervision. Also, you will not make it in an A320. It will be too fast for you and your knowledge will be found lacking. Furthermore, should you find yourself in the left hand seat of one in the near future, you will be working for an operator who will have lethally low standards.

I do admire you asking the questions you do but you must do your training in a structured classroom environment, not on an Internet forum with information from un-attested, unregulated and anonymous sources.

So where should you go next? You must find an operator with instructors and a range of aircraft from singles to twins. When you are earning a living flying a piston twin, then, and only then start thinking about a jump to a turbo-prop and after that an A320. It's either that or pay for a considerable amount of Procedure Training (sophisticated cardboard bomber) under supervision, and the key bit is 'supervision'.

George Yogi 4th Jun 2014 09:18

Your inputs are gladly taken and accepted.
Thank you PM

I-WEBA 5th Jun 2014 19:17

I profit by your great disposability and as I am really curious.

I'd like to know when usually APU is started during boarding and for an A320 how much extra fuel do you board for APU use during boarding?

Kind regards

flyboyike 5th Jun 2014 19:35

Usually 10 minutes or so before push, unless ground support has an issue or is unavailable. Fuel thus burned is negligible enough to not even be thought about.

Piltdown Man 6th Jun 2014 09:00

An E190 APU burns 90-250 kgs per hour, depending on electrical and bleed loading. We turn it on as late as we can to save noise, fuel and use (ie. economy). So the latest is just before departure, the earliest depends on cabin temperature (or if I want a tea - which requires bleed pressure). So the longest we might have it running is 30 minutes before departure. It is normally turned off immediately following the second engine generator coming on line.

glendalegoon 7th Jun 2014 00:54

piltdown man


do you like the E190? is it normal control or FBW? do you like that ram horn stick?

what is normal mach cruise?


All times are GMT. The time now is 11:03.


Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.