UK Defuelling

[Agaricus bisporus]

Following a thread in the SLF section a question has arisen about defuelling airliners at UK airports. I had always understood that defuelling was virtually impossible at UK airports. Is this the case? If it does happen, who does it (the fuel company or a maintenance organization?) What happens to the fuel? Can it be easily re-used? How long might it take to organise? Anyone done it?

Any other info on defuelling?

[BOAC]

Never done it, and have been advised not to try as it could take a long time to find an empty bowser. The fuel company would be the only ones with a bowser. In my day, 'defuelled' fuel could not be re-used in an aircraft. I do not know how long it would take to organise. The 'quickest' option is to reduce payload if it is a take-off weight problem. To burn-off 10T en route to Geneva if was a landing weight problem would be extremely difficult! To tie to the thread, it would be very difficult to remove only the baggage of the 37 off-loads from the aircraft.

Other option (if ldg weight limited) which may or may not be possible depending on programme would be to swap a/c onto another, longer route, but still difficult to get rid of 10T! T'was a screw up.

Fuel may have been loaded before flight crew arrived at the a/c, in their defence. I have caught an over-enthusiastic bowser 3 times in my career but luckily in time to avoid performance problems.

[spannersatcx]

Yes it can/has been done, requires maintenance and bowser man.

Fuel removed can only go back in the same a/c or same companies other a/c. Or disposed of, the cost of which is picked up by the airline.

Done it several times, it can take a bit of organising, I understood that it was a requirement of the airports to have an empty bowser available, not sure if it still is.

I wouldn't imagine that it would take too long to get 5T off a 320.

[Nubboy]

Finding an empty bowser is the tricky bit, most fuel companies won't mix off loaded fuel with fresh stuff. They say as they have no control over the aircraft tanks, they have to treat any bowser accepting it ass contaminated, and require a clean out before it can be used to fuel other aircraft.

This sort of thing sometimes happens when the aircraft type for the flight is swapped. Seen it twice when a 320 has been replaced by a 319 and the aircraft was refuelled to a predetermined minimum.

[Mr @ Spotty M]

As in my posting on the SLF thread, it is possible, but normally takes an age to get a refuel company to take it off.
It is done by the refueller and an engineer as it is not straight forward to remove.
It normally gets put back onto an aircraft from the same airline or if it is removed due to maintenance, it may get put onto an aircraft linked to the maintenance organisation.
The fuel removed is checked for water and other contamination before it can be removed from the aircraft.
I don't know of any fuel company that will remove a few tons of fuel, unless it has been agreed that operator "A" will take it.
What is the fuel company going to do with the fuel which has tied up one of its bowser, if it can not off load it ASAP?
Looks if spannersatcx has beat me to it and l think we agree with each other.

[Sir George Cayley]

At airports with hydrant refueling, bowsers are scarce.

If empty bowsers are brought onto site without proper checks then fuel drawn down into them could become contaminated with FAME, limiting its further aviation use.

Sir George Cayley

[411A]

It is normally much easier to offload pax/baggage/cargo than to try to defuel.
The pax are not normally pleased, however.:{

[Denti]

To burn-off 10T en route to Geneva if was a landing weight problem would be extremely difficult!

True, 10t is quite a bit, but you would be surprised how much you fuel you can burn if you want to do it. Had to get rid of a few tons of fuel in a hurry in a 737 once (night curfew, wrong calculated trip fuel) and cruising at 320 kts, gear down speed brake up in FL110 burned through the stuff like crazy. Not very comfortable of course, and the noise level was, well, bad.

[osmosis]

As written in another thread some months ago, I was involved in a defuelling of a Bandit in another life whilst the temporarily unloaded pax looked on from inside the terminal. I know it's not on the grand scale of which you guys are speaking but it does happen. Light years ago though.

[BOAC]

you would be surprised how much you fuel you can burn if you want to do it
a) Not surprised - done it
b) 10T on a GVA???? That's about 8T an hour.

[Jonty]

I have de fuelled a couple of times. Once at BHX and another at TFS. The biggest problem is finding an empty bowser, you usually have to wait for one. But once its turned up it doesn't take long to do.

[Capot]

As an airport, we could and would defuel on request into an empty bowser, subject to there being one, or indeed in a real emergency into a bowser with enough empty capacity.

All the fuel in the bowser was then returned to the storage tank, so that it would go through the same filtering and quality control system that fuel delivered by road bridger would go through. That would include checking for water, sediment and compatibility before putting it into storage, and quarantining the fuel until that was carried out with a satisfactory result.

However, the airport owned ran the fuel storage and supply facilities, buying the fuel from the oil company as it went into the storage, and was able to make irs own rules, within the regulatory requirements. (http://www.pprune.org/www.skybrary.aero/bookshelf/books/1206.pdf)

The charges for doing this were rightly horrendous, but if it was needed at all, the process was worth paying for.

As a fuel supplier, who also did the handling and load control, we would question any strange uplift instructions from crews and prevented more than a few defuels becoming necessary.

[Piltdown Man]

At times in the UK it is difficult enough to get the standard things accomplished during a turnaround let alone get something non-standard performed, like de-fuelling. As soon as you make a such a request, the average dispatcher will look confused, and then tell you it's not possible and then play the "elf'n'safety" and/or "airport regulations" card/s. For the greater good, it is better to disappoint and really annoy people who have paid and fully expect to fly by off-loading them whilst delaying those who will be flying.

How do you get over-fuelled? I've had the following:

1. Not reading my estimated ZFW (correctly) and then ordering too much in an attempt to save money.
2. Number spoonerisms (if such things exist), like ordering 5,700 kgs and ending up with 7,500 kgs.
3. Finger trouble on the refuelling panel.
4. Tanker faults. I've seen one pump until fuel was vented overboard through the fuel vents.
5. Poor or miss-communication.
6. Aircraft fuel system problems (both hardware and software) whereby the aircraft doesn't shut the fuelling valves when it should. This appears to happen rather a lot on electric aircraft.
7. ...and so on.

Solution: For flight deck and engineers - When fuel really matters watch the refuelling process and for tanker drivers, calculate the expected uplift before refuelling and stop the pump when this figure starts to be exceeded.