Here's Why This Airline Is Weighing Some Of Its Passengers

A Finnish airlinemade headlinesthis week after weighing some of its passengers before they boarded planes.

Somereports suggested this would become the airline’s new normal, but in fact, the weigh-ins ran for a limited time and were totally voluntary. Still, they’re worth discussing for the interesting reason behind them. 

On Tuesday and Wednesday, Helsinki-basedFinnair asked for passenger volunteers to be weighed before departing Helsinki Airport. The airline did so to check its unique passenger population against weight estimates provided by theEuropean Aviation Safety Agency, according to the airline’s communications directorPäivyt Tallqvist

Passengers who volunteered boarded a scale with their outerwear and carry-on luggage. Their weight was only visible to the airline clerk, Tallqvist told HuffPost.

A Finnair pilot boards the scale with his carry-on bag at Helsinki Airport. He was one of some 180 volunteers to be weighed by the airline.

Like many European airlines, Finnair relies onpassenger weight estimates provided by the EASAin 2009, Tallqvist said. They use the estimates along with the weights of checked luggage, aircraft and cargo tomake important safety calculationsthat affect balance, performance and fuel consumption, she added.

The EASA’s weight estimatesput the average male passenger at about 187 pounds and the average female passenger at about 147 pounds. However, passenger weights can vary by nationality, ticket class (for example,men in first class tend to weigh more than those in economy, the BBC reports) and time of year (Finnish passengers usually contribute more weight in winter due to their bulky coats, Tallqvist said). Finnair wants to collect its own data so it can be sure what its own average passenger weighs.

“This is part of having a very strong safety culture in our organization,” Tallqvist said. “We want to see if the data we’re using for calculations is accurate. We use them for every flight, and they’re important for the aircraft’s performance. When you explain this to [passengers], they understand.”

Finnair gate agents stand ready to welcome volunteer passengers during this week's tests at Helsinki Airport.

Finnair is analyzing the results of this week’s test and will weigh about 2,000 more passengers on a voluntary basis during winter and spring, Tallqvist added.

This isn’t the first airline to break out the scales. In 2013, now-defunct Samoa Airlines attracted media attention for its practice of charging passengers partly based on their weight. In 2015, Uzbekistan Airlinesannounced it would weigh passengersbefore boarding, citing an allegedly bogus international airline rule. The airlinezapped its programbefore any weigh-ins took place. The following year,travelers filed complaintsagainst Hawaiian Airlines for weighing them before flights to American Samoa, whichthe airline said was part of a testsimilar to Finnair’s. 

This article originally appeared on HuffPost.