A question to all you ground crew that work with heavies.

RatherBeFlyingInCanada · Fri Apr 13, 2007 4:31 am

When you are pushing back a/c (ie 737, A320, etc) do you put in the gear pins or do you do it without?

Just curious.

CGZMT · Post by **CGZMT** » Fri Apr 13, 2007 6:01 am

Depends on the Aircraft i think. For all turns with the 737 and the Airbus family we put the bypass pin in the nose gear and thats about it. For longer tows there might be additional but i have no idea about them!

conehead · Post by **conehead** » Fri Apr 13, 2007 6:43 am

It may be an "airline specific" type of thing. Air Canada used to use nose-gear pins in the past, but no longer does. There were several (lots) of cases of the pin being forgotten, the aircraft departing, takes off, can't retract nose gear, returns to airport, lands, taxi to ramp, pin gets removed by red-faced rampie, aircraft departs once again. As CGZMT stated, there is a pin inserted in the A320 nosegear, but it's not a downlock pin. It's to place the NWS system in "bypass" mode, so the pilots can't induce any input while the tractor is hooked up.

WRX · Post by **WRX** » Fri Apr 13, 2007 6:47 am

737-200 has no bypass pin. just a pump has to be off. otherwise the towbar safety pin snaps.

319/320/321/330, 757, 737NG, 747, CRJ, has one bypass pin for push backs and tows.

737daytripper · Post by **737daytripper** » Fri Apr 13, 2007 7:27 am

conehead wrote:It may be an "airline specific" type of thing. Air Canada used to use nose-gear pins in the past, but no longer does. There were several (lots) of cases of the pin being forgotten, the aircraft departing, takes off, can't retract nose gear, returns to airport, lands, taxi to ramp, pin gets removed by red-faced rampie, aircraft departs once again. As CGZMT stated, there is a pin inserted in the A320 nosegear, but it's not a downlock pin. It's to place the NWS system in "bypass" mode, so the pilots can't induce any input while the tractor is hooked up.

If the pin is there to disable NSW, then how could the aircraft take off with the pin left in?

Mitch Cronin · Post by **Mitch Cronin** » Fri Apr 13, 2007 7:37 am

I thought the man was asking about gear pins? Why you guys are confusing the issue with nws bypass pins I don't know... ...

Towing or pushing with or without any gear pins is going to be company specific, unless there's a manufacturer out there that demands it (I don't know of any).
Wardair always used gear pins for towing... Canadian did not. Policy at AC is not to use any gear pins. Boeing and Airbus both say their gear will not collapse under normal towing loads and no pins are needed unless something is already broken.

conehead · Post by **conehead** » Fri Apr 13, 2007 1:26 pm

If the pin is there to disable NSW, then how could the aircraft take off with the pin left in?[/quote]

Sorry about the confusion. On the A320, a bypass pin is used to disable NWS. I'm not aware of any 320's departing with this installed. (You're right, he would have trouble taxi-ing, and there is also flightdeck indication that the bypass pin is installed.) The a/c taking off with downlock pins installed always seemed to be Boeings.

Chop&Drop · Post by **Chop&Drop** » Fri Apr 13, 2007 2:15 pm

Now here is an interesting point, Air Cananda doesn't require pins for towing, but jazz does....

invertedattitude · Post by **invertedattitude** » Fri Apr 13, 2007 2:40 pm

WRX wrote:737-200 has no bypass pin. just a pump has to be off. otherwise the towbar safety pin snaps.

319/320/321/330, 757, 737NG, 747, CRJ, has one bypass pin for push backs and tows.

It's been a while since I've pushed a 200, but my brain is telling me they have bypass pins, been a long time tho... I know the 300/500 does, but they're a generation older.

As an interesting note, the F100's have a bypass "Switch"

To answer the original question, in my 8 years on the ramp, almost every airplane I've pushed requires a bypass pin.

It's essentially a layer of protection

invertedattitude · Post by **invertedattitude** » Fri Apr 13, 2007 2:58 pm

Maybe I'm blind, or someone better trained can tell me, I see a bypass location on both of these airplanes?

737-200
http://www.airliners.net/open.file/0818088/L/

737-400
http://www.airliners.net/open.file/1003230/L/

I always wondered on the NG's why they moved the Bypass pin to the other side of the nosegear?

737-700
http://www.airliners.net/open.file/0303499/L/

sinjin · Post by **sinjin** » Thu Apr 19, 2007 12:59 am

Chop&Drop wrote:Now here is an interesting point, Air Cananda doesn't require pins for towing, but jazz does....

Jazz is also using diferent aircraft. Dash 8 must have the gear pins installed and the nose wheel lock pulled out because this is demanded by bombadier. I am sure that jazz will remove this requirement as soon as they stop flying Dasy 8's.LOL

Mitch Cronin · Post by **Mitch Cronin** » Thu Apr 19, 2007 3:30 am

Krikey some of you guys do seem to love confusing issues don't you?....

The original question was about gear pins, not bypass pins, (which I certainly hope we all know are not the same thing?!?)

737-200's built later on in their production run did include the ability to install a nose wheel steering bypass pin, but just like it's earlier sister ships, it wasn't needed.... Their 'B' pumps (electric) couldn't be run without the parking break set, so that wasn't a worry (unless something was broke, but that's another story)... But the 'A' pumps (engine driven) would pressurize soon after starter engagement, so as long as you either delayed engine start during a push, or made sure the 'A' pumps were switched off, you'd be ok.

Flybaby · Post by **Flybaby** » Thu Apr 19, 2007 9:19 am

I never towed a heavy, well except for out of the horseshoes, but I've pushed a lot of planes and I didn't even know of a down lock pin before this post.
As for the bypass pins, just about every plane I pushed required one except the F100, RJ's and I think the 727. It's been a while so I might be wrong but the F100 had a bypas switch where you hook up your ground headset; The RJ's I was told it was in the cockpit or didn't require a bypass switch, I don’t remember exactly; and the 727 I forget if it also had a bypass pin, but I remember disconnecting the nose gear scissors just like a Ho prior to push.