747 Nosewheel Pin Removal
Thread Starter
Joined: Nov 2006
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From: EGLL 270° 4DME
747 Nosewheel Pin Removal
Is it is a common airline SOP to visually confirm from ground crew that the nosewheel pin has been removed .. i.e groundcrew physically holding it up to display for aircrew to see after removal?
Joined: May 2000
Posts: 3,204
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From: Seattle
Except, in the case of the 747, that pin is a nosegear steering cutout pin used by the ground crew during pushback, NOT the landing gear safety pin that prevents the gear from being raised. The gear safety pin is a preflight item, and should NOT be installed during normal ops. It is well hidden, high up in the linkage in the nosegear well. The steering cutout pin is installed near the intercom box just above the nosegear tires, and is usually installed on the ground.
I don't know how many other airliners have the steering pin.
I don't know how many other airliners have the steering pin.
Joined: Jul 2005
Posts: 319
Likes: 96
From: Honolulu
We confirm on the headset as well as visually. I'm sure it would happen on occasion, though probably not that much. Our company has at least one mechanic on the headset on pushback and they are pretty reliable for things like this. It would also become obvious at the first attempt to steer if the pin was still attached.
Joined: Apr 2000
Posts: 520
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From: Middle East / UK
That's what I was refering to. The steering bypass pin.
Except, in the case of the 747, that pin is a nosegear steering cutout pin used by the ground crew during pushback, NOT the landing gear safety pin that prevents the gear from being raised. The gear safety pin is a preflight item, and should NOT be installed during normal ops. It is well hidden, high up in the linkage in the nosegear well. The steering cutout pin is installed near the intercom box just above the nosegear tires, and is usually installed on the ground.
I don't know how many other airliners have the steering pin.
I don't know how many other airliners have the steering pin.
Mistrust in Management
Joined: Mar 2000
Posts: 986
Likes: 11
From: UK
Seeing the 'pin'
On all the Boeings (and the A520/319) I've operated it is important to see the steering pin before commencing taxy.
Seeing 'the pin' ensures that the ground crew are not still in front of the nosewheel and are clear when you commence the taxi.
I have had the pin, taxied off to find that I had no nosewheel steering. I'll get back to you on how we fixed that 'cos for now I can't remember and can't even remenber which aircraft type it was - the pin had been removed however.
Regards
Exeng
Seeing 'the pin' ensures that the ground crew are not still in front of the nosewheel and are clear when you commence the taxi.
I have had the pin, taxied off to find that I had no nosewheel steering. I'll get back to you on how we fixed that 'cos for now I can't remember and can't even remenber which aircraft type it was - the pin had been removed however.
Regards
Exeng
aka Capt PPRuNe
Joined: May 1995
Posts: 4,541
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From: UK
Several years ago when I was on the B757, we pushed back (at LEPA) and got the wave off from the push-back crew with the pin being shown. As we started to taxi we quickly realised that something was wrong and the a/c was not responding to steering commands.
After a lot of head scratching and getting the ground crew back we had to shut down engines. We got some steps and had to wait for an engineer to show up. Eventually, the wise old engineer spotted the problem.
When inserting the steering bypass pin, a small lever has to be held back against a spring before the pin can be inserted. Normally, when the pin is removed the lever is spring loaded to latch back into place. However, on our aircraft, there was an accumulation of old grease and grime which had become tacky enough to override the spring on the lever.
When the pin had been removed, no one had checked to see if the steering bypass lever had clicked back into the normal position. The wise old engineer used the equivalent of some WD40 to clean the spring loaded steering bypass lever and 'hey presto', all was back to normal and we could get home.
So, when you see the steering bypass pin being waved at you, it does not guarantee that your steering will actually work. I always take it to mean that the last person hanging around the nose gear is clear of the aircraft and there is no ground equipment in the way.
Nowadays, when checking for the steering bypass pin from the lofty height of a B744 flight-deck, I would challenge even the youngest and sharpest person on the flight-deck to actually see the 'pin'. Maybe on a clear day with the sun behind you. As long as I see the black (with a few hints of red) flag being held aloft I will assume that the nose gear area is clear. As for the steering bypass being neutralised, I will look for some steering response before we have moved very far to confirm that all's well down below.
After a lot of head scratching and getting the ground crew back we had to shut down engines. We got some steps and had to wait for an engineer to show up. Eventually, the wise old engineer spotted the problem.
When inserting the steering bypass pin, a small lever has to be held back against a spring before the pin can be inserted. Normally, when the pin is removed the lever is spring loaded to latch back into place. However, on our aircraft, there was an accumulation of old grease and grime which had become tacky enough to override the spring on the lever.
When the pin had been removed, no one had checked to see if the steering bypass lever had clicked back into the normal position. The wise old engineer used the equivalent of some WD40 to clean the spring loaded steering bypass lever and 'hey presto', all was back to normal and we could get home.
So, when you see the steering bypass pin being waved at you, it does not guarantee that your steering will actually work. I always take it to mean that the last person hanging around the nose gear is clear of the aircraft and there is no ground equipment in the way.
Nowadays, when checking for the steering bypass pin from the lofty height of a B744 flight-deck, I would challenge even the youngest and sharpest person on the flight-deck to actually see the 'pin'. Maybe on a clear day with the sun behind you. As long as I see the black (with a few hints of red) flag being held aloft I will assume that the nose gear area is clear. As for the steering bypass being neutralised, I will look for some steering response before we have moved very far to confirm that all's well down below.
