What are the yellow pipe/tube things?

[LambOfGod]

I was watching all the wicked aircraft out the window whilst waiting for my flight. On a 767 I saw these yellow pipe things that some ground crew were rolling up, I think they were connected to the aircraft somewhere. So what do they do? And are they new because I've never seen them before.

Thanks blokes...

[gatbusdriver]

air conditioning

[CR2]

Maybe an airstarter

[LambOfGod]

Hmmm, I was thinking air conditioning too. So your 100% on that? Is that why I only see them sometimes, not hot enough to use them. They looked about 20-30cm in diameter and had black lines on them.:\ They were connected to the bottom of the boarding tunnels which goes upto the AC door.

They looked a little 'low pressure' to be for the airstarter. If your referring to the starter for the turbines.

[exeng]

Air conditioning and not air for starting engines.

If the APU is U/S and air is required for engine start then an air start cart supplies air to the manifold via hoses approximately 5 inches in diameter - these hoses are generally not yellow in colour either in my experience whereas air conditioning hoses are generally yellow and approximately 12 inches in diameter.

Regards
Exeng

[Intruder]

Could also be refueling rigs, hence the "pipes" description...

[Bullethead]

Various airlines are implementing a policy whereby running the APU on the ground is considered too wasteful of fuel so instead they are requiring crew to use ground power and ground supplied conditioned air for cabin cooling and only starting the APU just prior to departure.

Ground electrical power and ground conditioned air have pretty much always been available, in case of aircraft systems failures, but it's the use has become more common recently due to the fuel price increases which is why you'll notice the yellow and black tubes more amd more.

Regards,
BH.