The other day I pushed out the Air Canada flight and the pilot wanted the pin removed before we disconnected from the aircraft. We are taught that the pin is last thing out. The pilot however said that the pin can be removed anytime the parking brake is set.

Could somebody clear this up?

 

I've witnessed first-hand an A320 pushed with no bypass pin inserted, though it was done completely in error. The gate lead failed to notice that it was not inserted before the push.

From the ground, nothing seemed to appear or behave any differently (obviously nothing to go by, though.)

I work on the ramp as well, so I can't say with any definitive-ness, but I *think* that all the bypass pin does on the A320 family (and probably most other aircraft) is disconnect nose gear steering from the tiller in the cockpit, as a safeguard from the captain trying to turn the wheels while the nose gear is still connected to the towbar and tug, which would obviously cause damage and be dangerous for the ground crew.

I've never heard of your circumstance happening. That would be against company policy at my airline, and I imagine at most others.

 

Yes, the bypass pin is used to disconnect the tiller from the nosewheel. There was a problem with the early family of 320's that the nosewheel would jerk on its own with no input from the pilot, and that would be dangerous if the tow bar was still attached to the nosewheel (and not the tug also). It would snap the bar around and catch rampers legs (apparently happened a couple of times). Also it allows greater swing of the nosewheel, without it locking hydraulically. You can still push back within an arc of movement and the airplane will act normally anyway. Airbus has since fixed the problem, and I believe it was changed in our FOM, but I can't verify that cause I'm currently furloughed with no manuals.