# Weighing Airline Passengers for Precise Estimates

MIE Professor Mohammad Taslim explains the benefits of weighing airline passengers in addition to their luggage before a flight.

This article originally appeared on Northeastern Global News. It was published by Tanner Stening. Main photo: Finnair plane is seen at the airport in Balice near Krakow, Poland. Photo by Jakub Porzycki/NurPhoto via AP

## Why is Finnish airline Finnair weighing passengers? A mechanical engineer explains.

Finnish airline Finnair this week instituted a new voluntary policy whereby it is now weighing passengers in addition to their luggage.

The airline said the change is meant to tune aircraft balance by offering more precise estimates of cargo weight prior to lift off.

Why is Finnair asking customers to step on the scale? Many airlines use industry averages in their own load estimations. But the Finnish airline has its own weighing program, and updates its passenger averages every couple of years or so, according to CNN.

Mohammad E. Taslim, professor of mechanical and industrial engineering at Northeastern, says determining an aircraft’s estimated weight is most critical prior to takeoff, “when the plane’s total weight is maximum.”

Mohammad Taslim, a professor of mechanical and industrial engineering, poses for a portrait outside Snell Engineering on Monday, Feb. 6, 2023. Photo by Alyssa Stone/Northeastern University

“[The] weight then gradually decreases as the plane flies towards its destination because of the continuous use of the fuel,” Taslim says.

He says airline dispatchers can calculate the weight of an aircraft using a fairly straightforward formula: you take the weight of the plane itself, then add its payload, which includes the aircraft’s fuel, passengers, baggage and cargo. Any meals or liquids on board are part of the overall calculus.

So too is the distribution of all of the above within the plane itself. On commercial flights, it’s not uncommon for flight crew to ask passengers at the front of the rear of an aircraft to move seats. That’s because airlines balance their weight around a center of gravity, much like how a seesaw functions.

Taslim suggests that some airlines have the capacity to determine their aircrafts’ weights with some degree of exactness.

“Planes do have an electronic scale that weighs them before takeoff, but I suppose by adding up the passengers’ and luggage weights, airlines get a more accurate measure of the total weight,” he says. “I have heard of cases where part of the cargo was unloaded to be flown later.”

Read full story at Northeastern Global News