stifle

I suspect if the bin is chock-full of people's bags of anvils, it might take the bin over its safe latch limit.

snapofish

Sorry if this is a bit out of point but I have a dilemma. My carry on bag fits most of the BA stated dimensions except that it's 59 (including the wheels and handle) rather than 56 cm in height. How likely is it that I'm going to have to check it in? It's only 3cm!

LTN Phobia

You probably won't be able to fit it into the overhead locker wheels first (as you are supposed to) if you are on a 737 or an Airbus. If the flight is busy, it's entirely possible that you will have it taken off you on board, if you get that far with it, and have it put in the hold.

It depends on how busy the flight is, but if it is, it's very likely you will be asked to gate check it especially on 737/Airbus because you will end up taking up two people's luggage space in the overhead locker. 3 cm over is very obvious actually - I can spot them a long way away and I'm just a regular passenger.

You should buy a smaller cabin bag because it is not within regulation size on any airline as cabin baggage as far as I know.

corporate-wage-slave

You'll probably get away with it if you are travelling CE and/or the 'plane is lightly loaded. It's the consistency factor you won't get, there's a chance it will be taken into the hold some of the time. Depends also on how flexible the bag is. If it's a fairly rigid rollaboard then it's at risk. If it's a more floppy holdall with wheels then you'd be fine, especially if the handle is lower down or the wheels are a bit spongy.

If you're doing a lot of travel you should stick to the right sizes, or travel with a floppy holdall without wheels (in which case you can get away with a lot more). If it is occasional travel and it ending up in the hold is not the end of the world, then I guess you could take the chance. If you have hold luggage as well, then I don't fancy your chances, it will probably be captured at check in.

But it is a bit inconsiderate on other travellers if your bag has to go sideways and takes twice the space of other passengers.

travelinfoo

Make that extremely inconsiderate. The space above is not just "your" space. It is for 3 ppl. I've seen that a number of times, including times when the case could fit on wheels fits but the passenger is too lazy to position it properly.

Washington DC

Not strictly allowed, but 99.9% of the time they'll let you take it on. You will also be able to store it wheels first I think, so don't worry about being too selfish. Don't hang around for too long before boarding though!