Ground operations via ATC?

[LGW15]

I have a burning question to what involvement ATC has in ground operations.

My question or questions are:
1. How does a tug know when an aircraft is ready for departure? Is this controlled by ATC?

2. How does the airbridge system work? I doubt this is via ATC so how do the ground staff know what stand/gate the A/C has been allocated to so that they can bring the bridge to the A/C?

[Carbide Finger]

Erm OK?

1 ATC would only be contacted if the tug wanted to move off the apron ie when crossing an active runway etc

2. The airbridge is operated by the groundcrew/dispatcher. ATC has no input there.

Stand allocations are usually passed to ATC via computer. At London City ATC plan the stands and then tell the ground crew, although this may have changed since I was last there.

If airbridges are available the aircraft taxiing in will taxi down a line and then stop when a lens/light system tells them to. The airbridge is then moved into place.

Hope this helps

CF

[055166k]

1. When the aircraft is ready the pilot will talk to ATC on the appropriate radio channel to ask for permission to start engines and push back from the stand. ATC will give permission when it is OK. The pilot is also in contact with the ground staff and/or tug driver via a kind of intercom system and can relay intentions and any ATC instruction received. When that is all done the ground staff will disconnect the intercom cable [which you may see...it is normally plugged in somewhere near the front of the aeroplane ] and walk to a position so that the pilot can observe a hand signal to confirm that all the ground equipment and people are out of the way. The pilot can then request permission to taxi from ATC.
2. The airline will know in advance which parking gate has been allocated by the airport authority. The ground staff will be ready to meet the aircraft....either ATC or the airline company will have radioed the parking position to the pilot. Last time I worked at an airport I recall that an airbridge operator had to be correctly qualified to "drive" the bridge...it is a responsible job because it could so easily damage the skin of an aircraft.
Hold out a finger at full arm-stretch, and a finger of your other hand about half the distance away.....move your head from left to right and back and notice how the fingers line up one behind the other.....well the pilot can use a system of pre-positioned lights or markers in much the same way to assist parking in the right spot for the airbridge....or sometimes a marshaller will do the same job.
I apologise if I've oversimplified.....I don't know what you know and therefore I answer with due respect.

[TheOddOne]

The tug crew also monitor the RTF so that they can hear the instructions given to the pilot, as a safety backup to ensure that the instructions passed to them by the crew are the same as those given by ATC.

At Gatwick, we have a series of 'standard' pushback manoeuvres, unique to each parking position, which the tug drivers have to know off by heart. This saves time on the radio for normal operations. However, sometimes these are varied by ATC, for instance if they want the aircraft to push far enough back to allow an inbound aircraft on to the same gate. Occasionally, visiting crews whose first language isn't English don't fully relay all this info to the tug crews; this is where the crew monitoring ATC comes in very handy.

You will also notice the ground staff holding up a pin attached to a length of red ribbon. This pin is inserted into the nosewheel steering mechanism to override the aircraft's steering system and allow the tug to turn the aircraft. Waving this pin at the crew indicates that they have control over the steering.

Pushback is actually quite a complex process and the ground crew not only carry out a comprehensive final walkround to ensure all hatches are secure and that nothing looks damaged or out of whack, but they also monitor engine start, to make sure that no-one is going to get blasted and that fuel doesn't start leaking out or whatever. Correct setting of brakes at all stages is another major issue and the ground crew are firmly in charge, here.

Being a part of the pushback crew is a highly responsible position and most of the folk I know who do this job take flight safety very seriously.

TheOddOne

[CAP670]

At Gatwick, we have a series of 'standard' pushback manoeuvres, unique to each parking position
However, sometimes these are varied by ATC, for instance if they want the aircraft to push far enough back to allow an inbound aircraft on to the same gate.

Same procedures at Luton - where the Airport Authority allocates the stand/gate and communicate this to ATC via a computer link.

...which the tug drivers have to know off by heart.
Same principle at Luton - except that some of the operators' ground staff/tug drivers don't seem to have learned or have forgotten what they're supposed to know about standard push-back directions!! This can cause ATC/GMC difficulties.

:oh:

[LGW15]

Thank you for all the excellent replies.

Only really looking at how they do it at Gatwick as that is where I am closest to.
I always thought it must be complex so I wanted to know how exactly they do it as can't seem to find out elsewhere.

Thanks again.
:ok: