Passengers warned over little known baggage rule that could end up costing you

People thinking that the early rays of sunlight in spring are a good reason to start looking at holiday destinations should remember to double-check how big their cases are.

Yes, before you know the trees will be blooming, that little strip of mercury in the thermometer will be climbing steadily upwards and every holiday destination you can think of will be packed to the rafters with tourists.

Just hold your horses before you start booking flights and packing your bags as it's time time break out your old friend the tape measure.

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That's because airlines have some pretty strict rules about what you can lug onto their planes, and this is a case where size really does matter.

While you might want to pack a bag and have it stowed in the hold, many of you potential passengers may possibly prefer to travel light and only take what you can carry.

It eliminates the risk of losing your airport luggage or bringing more than you'd be comfortable carrying around, just make sure you know the dimensions of your chosen airliner's maximum dimensions.

The kicker here is that your suitcases wheels also count towards this size, so if you want to trundle along with your luggage, you need to make sure those pesky wheels don't push you over the limit.

Airlines really don't mess around when it comes to hand luggage size, and you can actually end up not making your flight if your bag is oversized by even a few cm - that includes the extra height provided by the wheels.

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You might want to think of getting the biggest non-wheeled bag you can find that still fits the limits to maximise storage space, and do be sure to check the airline's site to know exactly what those limits are.

On the other hand, you try trekking from one end of the airport to another thanks to the inevitable fact that your gate will be as far away as possible, while lugging around a bag without wheels.

It may cost you a few cm in packing space but the trade-offs can be more than worth it in the long run.

Just have a good think if you want to be carrying your hand luggage around with you or whether you'd rather let one of our species earlier and better inventions scoot it along the ground for you.

Meanwhile, if you want to know what happens to your larger luggage after you check it in, there's quite the adventure in store.