I used to interview candidates in a previous life, and essentially I was asking myself two questions; (a) Does this person have the qualifications and experience I am looking for, and (b) Do I want to sit next to them for 8 hours a day?
The second question is obviously more subjective, but a candidate's enthusiasm and interest in the company would go a long way to answering it. At the very least I would expect someone to have looked at the website and identified a couple of points of interest to discuss. The impression given by people who didn't ask any questions was that – rightly or wrongly – they were just going through the motions and were insufficiently prepared for the interview. In the context of a first flying job, that's not good – particularly when you'll be competing against people who would chew off their own foot for the chance of employment.
As Biggles says, it's a smart move to ask questions that lead to a positive answer. For example, asking about time to command would be better received at a small turboprop operator who struggles to fill left hand seats when times are good, as opposed to BA, where it's 10 years plus, and hardly a great selling point.
Ask around on Pprune, as most pilots will happily spare the time to offer advice on their company's interview formats and 'live' issues – we all remember what it was like getting that first job. [But please – do yourself a favour and thank them afterwards. I'm getting a bit narked by the number of people who send PMs asking for advice who then can't be bothered to acknowledge the reply].
If all else fails, you could have a laugh by asking the interviewers about their company's strategic direction. Chances are you'll know as much about it as they do, and you should at least get an interesting discussion out of it.
