Weighing passengers at check-in - it sounds like something Ryanair would pioneer, but this week, Finnair has been leading the charge.

Passengers at Helsinki airport flying with the national airline this week have been asked to step onto weighing scales prior to boarding.

The voluntary scheme - passengers who don't want to do it are still allowed to fly - is gathering data on passenger weight, to see if the estimates they're currently using to calculate fuel and safety are accurate. To date, FinnAir has used European Aviation Safety Agency (EASA) passenger standard weight estimates, which calculate 88kg for a male passenger, 70kg for a female, 35kg for a child - plus carry-on bags for each. The estimates were put together in 2009.