Were any of the passengers transferring? If so they could have boarding cards with the code share flight numbers on when checked in by the other airline. The crew may have taken on trust the flight numbers as they were seeing so many.
If it was a short haul flight which would probably make up part of a multiple sector day the crew could become confused with flight numbers. Another factor could be the way crew are rostered these days. By adopting CAP 371 as a rostering bible and not as intended, a set of minimum/maximum rules to prevent fatigue, crew are increasingly worked to the max. It's a common problem amongst the crew fraternity, in that working like that will lead to errors. Can I honestly say that I have recognised and digested every one of the 400-600 boarding cards I may see in one day then multiply that by 5 or 6 for the week, no.
It also depends on where you boarded the aircraft, if it was from the rear doors there is the likelihood that junior crew were manning the doors at the rear. It may sound odd but they may not actually know the flight number of that flight. Simply because if you are doing a lot of sectors you may have only taken real notice of your first sector by which you can gauge what time you need to turn up for work. That does happen.
Essentially the gate staff should direct the right passengers to the right aircraft, particularly if more than one flight is boarding. In their defence, the customer service teams have been cut back in many airlines and there are times when there are not enough up at the gate to do the job.
There is slight complacency that the people who turn up at your door are indeed going to where you are! We are expecting the odd one that may slip through at the gate, but not a whole herd!
It seems a series of mistakes would lead to this and I would imagine some very serious questions are being asked of the relevant people. There is the very real possibility that people will lose their jobs. Which is a shame if one of the factors is people working to hard.
Should it of happened? Absolutely not. A wake up call for all concerned.
If it was a flight where the crew were only operating a single sector then the answers are far less appealing.
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