Airliners On The Ground
Discussion
A couple of things I'm curious about after seeing some of the goings-on at Heathrow.
Why do some airliners taxi from the stand to the runw under their in steam while others get towed a fair part of the way by a tug? This appears to happen with identical models from the same areas of the airport.
Secondly, when the aircraft is taxiing to the runway, is there a speed limit for them? Some of them seem to just plod along whereas others move at a fair pace.
Any ideas?
Why do some airliners taxi from the stand to the runw under their in steam while others get towed a fair part of the way by a tug? This appears to happen with identical models from the same areas of the airport.
Secondly, when the aircraft is taxiing to the runway, is there a speed limit for them? Some of them seem to just plod along whereas others move at a fair pace.
Any ideas?
neenaw said:
A couple of things I'm curious about after seeing some of the goings-on at Heathrow.
Why do some airliners taxi from the stand to the runw under their in steam while others get towed a fair part of the way by a tug? This appears to happen with identical models from the same areas of the airport.
Secondly, when the aircraft is taxiing to the runway, is there a speed limit for them? Some of them seem to just plod along whereas others move at a fair pace.
Any ideas?
One of our resident Heathrow drivers might be able to confirm or deny, but the AIP entry implies that there are certain areas where towing is mandatory, presumably because of the risk of jet blast to the surroundings. As usual, a direct link to the AIP will expire almost immediately, so look here:Why do some airliners taxi from the stand to the runw under their in steam while others get towed a fair part of the way by a tug? This appears to happen with identical models from the same areas of the airport.
Secondly, when the aircraft is taxiing to the runway, is there a speed limit for them? Some of them seem to just plod along whereas others move at a fair pace.
Any ideas?
EGLL London Heathrow -> London Heathrow Aerodrome - Textual Data
"A318, A319, B737-500 and B737-600 aircraft using stands 102, 103, 104, 105 and 109 must
have the port engine fully shut down before entering the stand. If stand entry guidance is
unservicable and aircraft is marshalled onto stand, it will be stopped short and require towing
forward to correct stop position."
"All B747/400 aircraft on Taxiway Zulu must be under tow"
MitchT said:
neenaw said:
... Some of them seem to just plod along whereas others move at a fair pace.
Quite a few 737s that I've flown out of LBA on were not exactly hanging around as they headed for the end of 32 
TorqueVR said:
I've been a bit bemused by the parking arrangments at Dortmund. The aircraft are pushed back in to their stands and then leave under power, despite being backed right up to the terminal building. I assume thast the building was designed with the jet-blast in mind.
It does seem a bit of a Heath Robinson arrangement to shut the engines down, lift the nose wheel off the ground and shove the aircraft backwards, doesn't it? Despite the warning from the cabin crew, there's always a cacophony of clicking seat-belts when the aircraft comes to a standstill, as people try to get up before the plane has reached its final position.
neenaw said:
Secondly, when the aircraft is taxiing to the runway, is there a speed limit for them? Some of them seem to just plod along whereas others move at a fair pace.
Any ideas?
Almost always a function of who's driving - in our outfit the Captain always does the taxing, there's no steering tiller in the right seat. It's just like going out for a drive with a variety of different friends - some of them will be painfully cautious, others quite happy to wind up the speed a little where it's safe to do so. Human nature!Any ideas?
Edited by JWH on Wednesday 11th April 22:10
JWH said:
Almost always a function of who's driving - in our outfit the Captain always does the taxing, there's no steering tiller in the left seat. It's just like going out for a drive with a variety of different friends - some of them will be painfully cautious, others quite happy to wind up the speed a little where it's safe to do so. Human nature!
Where do your captains sit? 
Reminds me of the IL62 (think VC10 if you don't know what this is) that was stuck at Heathrow after the Korean Airines 747 was shot down.
The ground crew refused to touch it and after several days, it was realiised there was going to be no assistance coming a y time soon.
The only was the aircraft could "push back" was under its own power ie: reverse thrust.
I heard it from Hounslow which is about 4 miles away.
The ground crew refused to touch it and after several days, it was realiised there was going to be no assistance coming a y time soon.
The only was the aircraft could "push back" was under its own power ie: reverse thrust.
I heard it from Hounslow which is about 4 miles away.
mrloudly said:
JWH said:
Almost always a function of who's driving - in our outfit the Captain always does the taxing, there's no steering tiller in the left seat. It's just like going out for a drive with a variety of different friends - some of them will be painfully cautious, others quite happy to wind up the speed a little where it's safe to do so. Human nature!
Where do your captains sit? mrloudly said:
JWH said:
Almost always a function of who's driving - in our outfit the Captain always does the taxing, there's no steering tiller in the left seat. It's just like going out for a drive with a variety of different friends - some of them will be painfully cautious, others quite happy to wind up the speed a little where it's safe to do so. Human nature!
Where do your captains sit? 
As to the question, is there a speed limit? The FAA says you should taxi "no faster than a brisk walk" so take from that what you will...
In my experience, very, very slow can indicate a cautious captain, or some other things like: contract negotiations, trying to make extra money (pay is based on flight time which includes taxiing), or even if you have a take-off delay the capt might taxi slowly because passengers get annoyed when we are sitting still but don't notice so much if we're taxiing the whole time.
As to fast taxiing, well I've seen 40 kts on the GPS ground speed readout before!
JWH said:
Almost always a function of who's driving - in our outfit the Captain always does the taxing, there's no steering tiller in the right seat. It's just like going out for a drive with a variety of different friends - some of them will be painfully cautious, others quite happy to wind up the speed a little where it's safe to do so. Human nature!
Haha, pretty much the same at my airline except for the tiller being on the left. Edited by JWH on Wednesday 11th April 22:10
In my experience, very, very slow can indicate a cautious captain, or some other things like: contract negotiations, trying to make extra money (pay is based on flight time which includes taxiing), or even if you have a take-off delay the capt might taxi slowly because passengers get annoyed when we are sitting still but don't notice so much if we're taxiing the whole time.
As to fast taxiing, well I've seen 40 kts on the GPS ground speed readout before!
It's quite common now to shut an engine down for the taxi to the gate once the aircraft has landed and vacated the runway. Not always wise however if you are likely to face a tight turn or steep taxiway as you end up flogging the one engine and blasting all around you!!
There has been talk of aircraft taxiing out for take off with one engine shut down, but again, this will cause all sorts of issues if the donkey decides just before entering the runway that it aint in the mood for flight, plus the risk of unsupervised engine start fires etc etc!
I was a passenger on an ATR last week, and the crew only started the left engine as we approached the runway. Umm, setting take off power on a cold engine, I'd rather not myself!
There has been talk of aircraft taxiing out for take off with one engine shut down, but again, this will cause all sorts of issues if the donkey decides just before entering the runway that it aint in the mood for flight, plus the risk of unsupervised engine start fires etc etc!
I was a passenger on an ATR last week, and the crew only started the left engine as we approached the runway. Umm, setting take off power on a cold engine, I'd rather not myself!
Sifly said:
I was a passenger on an ATR last week, and the crew only started the left engine as we approached the runway. Umm, setting take off power on a cold engine, I'd rather not myself! :irked
Turbine engines get up to temperature pretty quickly compared to a car's piston engine.Gassing Station | Boats, Planes & Trains | Top of Page | What's New | My Stuff