Stepping on the scale can be stressful. Air travel can do that too. Now imagine having to weigh yourself before you can board your next flight.
That’s what Korean Air travelers flying domestically through Seoul’s Gimpo International Airport (GMP) and Incheon International Airport (ICN) would experience after the airline announced it would weigh passengers with their carry-on luggage to determine the average weight of to measure passengers.
But Korean Air faced backlash so quickly that it ultimately removed a message regarding passenger weighing on its website just days after the announcement, according to CNBC.
Air New Zealand also made headlines in May for weighing passengers departing Auckland Airport (AKL) for international flights.
This practice – while controversial for many travelers – is actually quite standard within the aviation industry.
And there’s good news for those who might not like having to see the scale: The airlines don’t pay attention to the individual weight of each passenger, at least not on most commercial jetliners. Instead, they look for a realistic average so they can better plan things like fuel consumption and loading capacity.
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Airlines may also occasionally weigh passengers so they can recalibrate the weight distribution of their planes for safe takeoff and landing, said Blaise Waguespack, a professor at Embry-Riddle Aeronautical University who specializes in airline marketing and operations .
“If you don’t have the right weight balance profile, one wrong gust, boom, you’re dragging the tail,” he said.
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For example, knowing how much weight an aircraft can handle can be important in situations where an aircraft is operating in an area with sweltering temperatures.
Bob Thomas, an Embry-Riddle professor in the university’s aeronautical sciences department, said airlines in areas where temperatures can get extremely hot may have to reduce the weight of their planes for takeoff.
“Most people don’t realize that weight affects not only the actual starting distance, but also the ability to climb over obstacles afterwards,” says Thomas.
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Passenger weighing is especially common among airlines that operate smaller aircraft, where the individual weight of each passenger is actually more important.
“The problem with weighing passengers is that every airplane has a weight and balance program, whether you’re a small airplane or a large airplane,” said Michael Suckow, a professor at Purdue University’s School of Aviation and Transportation Technology.
Suckow said airlines that fly planes like the smaller Bombardiers and Embraers tend to weigh passengers more heavily because the weight of passengers — along with fuel and equipment — can greatly affect the plane’s balance.
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However, for larger airlines that operate aircraft such as a Boeing or Airbus, weighing passengers is not as common. Instead, most airlines rely on surveys of a given sample — such as those recently obtained by Korean Air and Air New Zealand — to determine the average weight of passengers, Thomas said.
In the US, airlines can also determine aircraft weight distribution based on studies conducted by the Centers for Disease Control and Prevention. The survey, known as the National Health and Nutrition Examination Survey, weighs a sample of U.S. residents, which airlines can then use to determine a passenger’s average weight.
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Although U.S. airlines have other means to determine average passenger weight, an advisory circular from the Federal Aviation Administration says airlines may weigh travelers at any time.
It is ultimately up to airline regulators to determine how airlines determine weight distribution.
So some countries may require their airlines to have passengers step on a scale.
In the case of Korean Air and Air New Zealand, they follow mandates from their respective countries that require them to periodically update their average passenger weight calculations.
A spokesperson for Korean Air said the airline, along with other Korean airlines, weighed passengers and their carry-on luggage to provide data to the country’s Ministry of Land, Infrastructure and Transport for its Aircraft Weight and Balance Management Standards, which every be updated once. five years.
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“This is a government mandate and necessary for the safety of flight operations,” the spokesperson said.
Air New Zealand also reiterated that its weight surveys were a mandate of the New Zealand Civil Aviation Authority.
“Our passenger weight survey was a mandatory requirement of the Civil Aviation Authority, participation was voluntary and all data was completely anonymous, even to airline staff,” an Air New Zealand spokesperson said.
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And while this practice may seem invasive, the weight of each individual passenger and their carry-on luggage is typically kept anonymous: only the airline sees the total weight and each passenger’s data is anonymized. Additionally, passengers have the option to refuse to participate in weight surveys: both Korean Air and Air New Zealand emphasized that travelers could opt out of their respective weight surveys.
It may feel awkward when an airline asks for your weight, but know that this is common.
“It’s definitely an uncomfortable situation, an uncomfortable conversation, an uncomfortable request,” Suckow said. “But it’s something that the carriers have to figure out how to do when they ask for it [regulatory authorities] to validate their program.”