Push Back for A320

[Donesh I.]

Today, while looking for photo opportunities around near the domestic terminal I noticed something very peculiar which I have never seen before. All jetstar A320's were pushed back with the tractor attached to the port main landing gear. My questions to the more senior and experienced members of this group are:

1. How does the aircraft get steered? Is'nt the nosewheel the controlling factor?
2. How common is this practice?
3. Is it limited to A320's and other smaller single aisle aircraft or is this practice prevailent among the larger behemoths too.

I am attaching a couple of pictures for your reference.

cheers

[Tim Bowrey]

Hi there Donesh,

The machine is called a SCHOPF Power Push Unit(PPU) and used frequently at the main ports by Jetstar and Virgin domestically. Pilots are in control of the nose wheel and instructed when to turn via the headset.

Video (http://www.youtube.com/watch?v=9Nc5G_ExOmY)

[Mick.B]

What is the advantage of this ?

[Paul Hunter]

No broken tow-bars.

Seem a little quicker to push and disconnect than the tugs.

Only one person needed to operate the power push as opposed to a Tug driver & Ground crew on the tug.

Regards.

[Donesh I.]

Thanks Tim, You have been most helpful. This explains it. To be honest I was very puzzled

Cheers

[David N]

Pilots are in control of the nose wheel and instructed when to turn via the headset.


Thanks Tim, I didn't know this.

I thought Pilots would have been to busy starting the engines during push back.

Regards
David

[Chris Z]

Hi David. We start number 2 Engine first on the bay, and after about 15 seconds of spool up, we start the 'power pushing', as the hydraulic pumps are now working in order for us to steer, under the guidance of the fellow on the headset, controlling the power push unit.

It's not that busy during start up, as it's mostly automatic, and the Pilot Not Flying monitors the start, and the Pilot Flying the sector, controls the steering.

[Ben Smith]

Do they use these units on the E jets at all? The E 190 I was on last week got pushed out by a regular tug from gate 39 T2. I was surprised as I was expecting to see a PPU shuttling back into the bay when instead it was a tractor style tug...

[Tim Bowrey]

Hi there Ben, not used on any E-Jets.

[Ben Smith]

Well, there you go. Thanks Tim.

[Mick B]

Paul H
Seem a little quicker to push and disconnect than the tugs.

My observations, mainly relating to Virgin aircraft - they might be marginally quicker for the aircraft concerned, but once they start taxiing under their own power, there is 60 secs or so until the engineer can walk over to the tractor to retrieve it and drive it back to the bay (as I understand they can't be controlled directionally with the remote).

The end result is that they block the taxiway for the following competitors aircraft..but the Virgin bean counters wouldn't care about that!

[Nigel C]

But in the case of the virgin apron they're delaying their own aircraft as well, so I'm sure the bean counters either don't know, don't care , or factor in any small delay.

[Mick B]

I wasn't just talking about Sydney Nigel ;)