I would imagine that ATC cleared Virgin to push once the Jetstar A320 was on the bay, which would have been relayed from the flight deck to the guy on the headset. I doubt that the guy on the headset would have been able to see the tarmac markings from where he was & probably couldn't see the NIGS as well, so assumed that the 320 was on position when it stopped.
If there was no wing-walker, it would be difficult to judge the clearance at the wingtip. From the flight deck it often looks awfully close, so it would be the same for him. He possibly assumed that the wingtip was clear even though it looked close, because he thought that the 320 was on the bay. No excuse, but when the picture often looks like that & on time performance is heavily pushed by management, people just tend to rely on past experience, rather than double checking.
I would not be surprised to find that the major problem here is that the 320 didn't advise ATC that it was holding short of the bay. It has happened a number of times around the world. If they didn't feel that they needed to advise ATC for some reason, the pushback clearance to the 737 should have alerted them to the fact that someone was pushing behind them & then they should have advised ATC. Some seem to think they operate in a vacuum & really need to lift their situational awareness. They need to know where the various bays are around the bay they are going on to & listen to ALL radio transmissions, not just on the ground, but in the air as well.
Last edited by Oakape; 10th Aug 2013 at 23:31.