APU Fuel Consumption

[jettrail]

Hi everybody

Just a short question about the fuel consumption of the APU. How many fuel does the APU of the following aircraft need per hour on ground?

A340-300
A340-600
B747
B737-300/400/500

Thanks and a happy new Year

[modeselectorignition]

For the A340, look in FCOM 2.05.10, Flt Planing General. Cheers, Happy New Year.

[Spooky 2]

Roughly 200ph on the B767.

[Denti]

For the 737 300 and 500 we used around 80kg per hour depending on APU type and bleed air usage. -700 is around 80 to 120kg per hour

[DutchBird-757]

Roughly 80 kgs an hour of the AVRO's

[BelArgUSA]

747 Classic APU fuel consumption

The consumption of APU (Garrett GTPC-660-4) depends on the power generated (required).
APU used only for electrical (1 or 2 generators) generally will be using 400-450 kg/hour.
If APU is used for electrical generator(s) + 1 air conditioning pack, count on about 550-600 kg/hour.
Starting 4 engines using APU for pack bleed air is 100 kilos total for start.
Based on above, used to suggest to fuel 500 kg extra in nº 2 main tank which is the APU fuel source.
That is over the dispatch fuel required, plus my "personal little extra"...
xxx
For the 737, cannot recall, but should be same as a 727 APU (same type).
Count on 250-300 kg/hour for the 727-737... and 50 kg for start of engines.
xxx
Remember, your airline APU use is probably billed by the hours of use (Hobbs meter).
Is less expensive to use ground power units, electrical/air than APU.
Save the last drops for my Zippo cigarette lighter.
xxx

Happy contrails

[GlueBall]

External conditioned air [ground aircon] in tropical or desert climates is inadequate. Pax, especially FC & BC pax who fork over thousands of dollars for a seat, are entitled to "comfort" [22c] in the cabin. Whether the APU will burn 500 or 800kg/hr to maintain regulated cabin temperature is of zero concern. The fuel saving paranoia has its limitations.

[BOAC]

Denti has it right for the 737 - 80 at idle and around 120 for air and electrics.

[airman13]

hi belargusa, how are you my old fart?......are you on a sunny beach , as an aviator with more than 20.000 flying hrs is doing in these days, or you are staying home, drinking a glass of jack daniels......

have a happy new year 2009, my dear!!!!!!!!!!!!!

[jettrail]

Thx for your help modeselectorignition but unfortunately I don´t have access to the mentioned A340 documentation. I´m no pilot. I´m an employee of a ground supplier at a german airport. We´re planning to buy some external air conditioning units and I have to calculate the rental price.

I hope somebody can help out with more detailed info about APU fuel consumption of A343, A342 or A346.

Thanks a lot to all the others which helped me with input

Bye and happy new year

[run77]

Hi, do you know the B738 consumption for electrical only?

Thanks

[stilton]

Thought id gone through a time warp, perhaps 411A will reappear..


A ten year pause and then another post on this old topic


Is that a record ?

[Pugilistic Animus]

Stilton
A lot of oldies but goodies are making their return as of lately

[run77]

Im monitoring fuel efficiency and doing APU on ground project.

A pilot friend of mine ran a test on B738 APU with generator only and generator + packs. The result, APU with only generator consumed 10kg fuel for 5 mins while APU with generator + packs consumed 10kg fuel for 4.5 mins.

is this acceptable?
​​

[Chris Scott]

Two questions come to mind:
(1) What do you mean by “acceptable”?
(2) How did your pilot friend determine when 10 kg of fuel had been consumed?

Also, I’m surprised that turning on the packs only increased fuel flow by 11%.

[run77]

Originally Posted by Chris Scott

Two questions come to mind:
(1) What do you mean by “acceptable”?
(2) How did your pilot friend determine when 10 kg of fuel had been consumed?

Also, I’m surprised that turning on the packs only increased fuel flow by 11%.

Hi Chris,

1. Due to the experiment was only tested on 1 flight on the ground, that is why i need to know if it is logical and "acceptable".
2. During on the ground, the engines were off and the only source of power and aircond packs came from APU. Hence the 10 kg consumption was read from the FMC CDU and the timing of the 10 mins consumption recorded.

I'm also surprised the the difference is so little.

Regards