Airline puts international passengers on the scales pre-flight

An aircraft mass properties engineer and an eating disorder therapist weigh in on Air New Zealand's plan

Airline travellers are long familiar with having their luggage weighed before boarding a flight – but beginning this week until July 2, Air New Zealand will also be weighing passengers. To be specific, 10,000 international passengers on international flights.

Air New Zealand called the effort a "survey" and explained it is part of a Civil Aviation Authority requirement. It's also completely voluntary.

The airline completed a similar survey in 2021 of domestic passengers, but that was pre-COVID.

"Now that international travel is back up and running, it's time for international flyers to weigh in," said the airline.

For airlines, weight equals cost, and having accurate weight is important to ensuring there's enough fuel – which of course also adds to the weight.

As expected from an airline, Air New Zealand said it weighs “everything that goes on the aircraft – from the cargo to the meals onboard, to the luggage in the hold.”

As is customary, though, it uses an average assumed standard weight for customers, crew and cabin bags.

But as shapes and sizes of travellers vary, that standard is often contested. At a time when many airlines are adding extra rows of seats to an already compact passenger compartment, a more accurate weight could make the difference between profit and no profit.

A former aircraft mass properties engineer – commonly referred to as a "weights engineer" – told The Register: "In short, people are getting heavier and we need to have a way to calculate an average passenger weight that is in line with the times – not a standard from 50 years ago." As he recently left that role after two decades, he asked not to be named for this article.

"It is common for agencies such as the US FAA or Europe's EASA to periodically weigh passengers before flights to collect a baseline average weight, so Air New Zealand is just trying to stay one step ahead," he added. "However, making it voluntary would likely skew the results."

Air New Zealand is not only making the weighing voluntary, it promises the data will be collected anonymously with no visible display.

"I think making weighing voluntary is the ethical thing to do here. As with anything related to the human body, consent is important," Boston-based therapist specializing in eating disorders, Molly Robson LCSW, told The Reg.

"I think it could only trigger passengers if this data gets used in a stigmatizing or harmful way. What would be great is some awareness from the airlines of how potentially traumatic flying while fat is – updating the data while also acknowledging that airplane seats were designed with certain bodies in mind," she added.

But all the effort for accuracy of weight might in the end result in no change. A similar voluntary study from the European Union Aviation Safety Agency (EASA) carried out by Lufthansa in 2022 revealed no significant change from 2008 values.

And while Air New Zealand is weighing passengers voluntarily for the purpose of a study, there has been at least one airline to weigh passengers for the purpose of charging them on a sliding scale.

In 2012, now-defunct Samoa Air became the world's first airline to charge passengers by weight instead of seat.

Passengers booked their flights based on their weight and the length of the flight, and that weight had to be verified at the check-in counter.

The plan predictably shocked many. Some argued such a plan benefitted women and children, who tend to weigh less than men, and therefore prevented them subsidizing costs for their male counterparts. Weighing passengers is, however, uncontroversial when practised by operators of smaller aircraft, as on such vehicles a few stray kilograms can have outsized impact. Weigh-ins are therefore an important safety consideration. ®