Apu start while refuelling
 

Hi guys,

I can't find any reference, I knew previously (A320) it was avoided starting Apu while refuelling. Now I see most captain starting without any problem, just some of them prefer delay the bleed on after refuelling ended. Is there any reference that forbids turning on Apu BLEED while refu?

AMM Task 12-11-28-650-001-A General Refuel/Defuel Safety Procedures:
...
(19) Auxiliary Power Unit (APU) starts or shutdowns are permitted during refuel/ defuel procedures. If it is necessary to operate the APU, the limits that follow apply:
     (a) An APU start is not permitted during a refuel/defuel procedure if the APU has failed to start or an automatic shutdown has occurred.
     (b) You must complete a normal APU shutdown if a fuel spill has occurred during the refuel/defuel procedure.
...

Always made me laugh this one.

The aircraft being refuelled strictly forbidden, No HF or APU start while refuelling. However no limitations on the jet next door starting APU, engines, connecting or disconnecting power, keying their HF or testing a RADAR. Or for that matter the JCPL, baggage tugs, aircraft tugs, catering trucks etc starting while attached or working around said aircraft.

Yes indeed. SOP's like that don't exactly show a lot of confidence in the integrity of the equipment...
No doubt comes from the same school of BS thought processes that gave us "It is forbidden to use mobile phones in a petrol station"

Yep our Ops Manual prohibits us starting it up which goes against the FCOM and AMM as stated earlier. Over cautious perhaps, but I tend not to lose sleep over these things. I find there are much bigger issues with company ops manuals and procedures than starting an apu.

Yep, that's true, it's not a big issue usually. But these days, in Milan 35 degrees, it's very useful and during crew change, where apu is usually turned off, turning on as soon as possible-even if we're refuelling- it's a relief :))

For what it's worth..
My local airport states that APUs should not be started if the exhaust is within (15?) meters of the fuel tank vents. In practice this means that on most a/c APU start is not a problem. A330 with the stab tank is a possible exception, I haven't bothered to measure the distance.

However, as a general rule, APU shouldn't be started during refuelling on a/c that automatically do a power change over from GPU to APU due to the autorefuelling preset could glitch. It's not the end of the world but it has caused delays.

Good airmanship etc....:ok:

Apu start during fueling
 

Although an APU start is permitted on the B747 it will depend on the company SOPs as to whether they allow it. On the B747-444 it has a NBPT ( no break power transfer) when sellecting power on, I have always felt it prudent to not put power on when fueling.

Thanks for the AMM ref IFix.