Liquid falling from wing on 747 prior to takeoff

[Lazygraduate]

Was recently flying to and from The States and on the outbound flight, as we were taxiing to the runway, what seemed like an awful lot of clear liquid was pouring out from the end of the wing - slightly alarming! Obviously the plane and flight were absolutely fine, and I'm sure given the circumstances it wasn't fuel or hydraulic oil or anything like that - anybody know what it was likely to be? Water, I'm guessing?

Plus, a cheeky pic coming into SFO

[jjones]

since 911 they lock the cockpit door. this means that the pilots do not have access the toilet. there is a urinal in the 747 fitted next to the engineers seat. i am guessing someone took a leak as it is vented out of the air frame instead of into the toilet system in case hijackers pump gas back through the system and disable the pilots.





























the above may not be true.

[Jim Campbell]

Probably fuel i would say. Did it leak from the same spot as this one? http://www.youtube.com/watch?v=ZDGztFhweDk

I'm fairly sure there is more than one 744 driver on the forum who will be along in a minute to shed some light on the matter.

That bridge is bloody long. Is that the san mateo bridge?. Looks to be a good spot for a vmax run.

[Zad]

Maybe it had been washed and it was water which had pooled in the various nooks and crannies behind the control surfaces?

[c7xlg]

pretty sure that would have been fuel venting off as the sun warms up the wing tanks whilst on the ground.

[DuraAce]

c7xlg said:

pretty sure that would have been fuel venting off as the sun warms up the wing tanks whilst on the ground.

I'd go with that, as the vents for the wing tank groups are at the end on the underside of each wing tip.

[bumblebee]

c7xlg said:

pretty sure that would have been fuel venting off as the sun warms up the wing tanks whilst on the ground.

Correctamundo.......the outermost section of wing is where the Surge tanks are located. With full wing tanks it is not unusual for some fuel to vent if they are a little overfilled, or expansion occurs.

[Lazygraduate]

Very interesting, thanks

[Rower]

bumblebee said:

c7xlg said:

pretty sure that would have been fuel venting off as the sun warms up the wing tanks whilst on the ground.

Correctamundo.......the outermost section of wing is where the Surge tanks are located. With full wing tanks it is not unusual for some fuel to vent if they are a little overfilled, or expansion occurs.

Unlikely to happen on a Ryanair plane then.....

[MitchT]

Rower said:

Unlikely to happen on a Ryanair plane then.....

There's usually a guy from Ryanair running along under the wingtips of taxiing BA planes with a jug

[HoHoHo]

MitchT said:

Rower said:

Unlikely to happen on a Ryanair plane then.....

There's usually a guy from Ryanair running along under the wingtips of taxiing BA planes with a jug

Sorry, you're wrong.

Ryan Air never fill the tanks up











And that's a fact I have from an ex Ryan Air 737 pilot

[MitchT]

I meant he was catching the overflowing fuel from the BA plane so they wouldn't have to pay for their own.

[HoHoHo]

MitchT said:

I meant he was catching the overflowing fuel from the BA plane so they wouldn't have to pay for their own.

Sorry, missed that