Airline leg space - the final frontier!
This touches a raw nerve, or a raw knee. Lets delve a bit deeper.
The answer is yes! If the first question in your mind was, has the legroom shrunk over the years - the answer is yes.
Pitch and Width
To understand what we know to be true, we need to understand two variables - Pitch and Width.
Pitch, in simple terms, is the distance between two seats. See the diagram below1.
Seat Width is the inside distance between the two armrests of the seat. Seat width, too, is shrinking. 2
In 2013, Airbus did a study3 with the London Sleep Centre to identify the effects of seat width on passenger comfort on long-haul flights. The study ended up recommending 18 inches as the minimum seat width for long-haul flights. Yet many airlines still continue with 17-inch. The study only looked at 17-inch v 18-inch as options. It appears they were simply trying to go one-up on Boeing. We need more shoulder room than 18 inches. A similar study by Delft University4 validates the findings! I mean, come on!)
Airlines are not thinking of passenger comfort!
Airlines are always working on getting more people into aeroplanes while getting away with the basic passenger comfort they can get away with.
Thinner seats are one such innovation5. As seen in the figure below, if the seat is thin, it allows for more legroom within the same or lesser pitch. Thus, less plush seats are fast becoming the norm. The thin construction means that unless the seats are exceptionally well-built, they do not hold shape and wobble with weight.
Some airlines have also come up with a “smart idea” to reduce the number of lavatories on aeroplanes in order to cram more seats in. In long-haul flights (6+ hours non-stop), all the people will have to go to the lavatory at least once. Imagine everyone does so in an exceptionally orderly manner and takes, say, 2 mins (pee time). These days, there are barely enough lavatories to manage these natural processes.
Seats need to adapt to changes.
Humans are now taller and fatter than in the 1960s!
As per the Faculty of Industrial Design Engineering, the Delft University of Technology6, a seat width of 15.91 inches would have accommodated 95% of females in 1986, whereas the corresponding width in 2014 would have to be 17.1 inches to accomplish the same accommodation, a 7.4% increase in width. They have also found an increase in width at the shoulders and elbows.
And that results in two important points of consideration - comfort and safety. Aside from understandable considerations of comfort, we also need to understand that in any emergency, all these “wider” people will have to be evacuated within 90 seconds7.
The US Congress was trying!
The US Congress had, in 2018, given the FAA one year to establish minimum seating dimensions, including pitch and the distance between seatbacks, that were "necessary" for passenger safety. The FAA has not done so yet, i.e. till 2024.
US courts do not want to force FAA to adopt seating rules. The industry lobby maintains that the FAA should not regulate minimum seat pitch or width.8
High time we had comfortable seats in airplanes!
We can look at the seat dimensions of various airlines9, but it is clear that we need wider seats with more leg space. It is also critical for obese people.10
There should be international regulation that minimum leg and shoulder room should be enough for a 6'0" 120kg person to sit comfortably. I would say 35" seat pitch (as against the current 30") and 22" width.
What should be the seat angle in the seat-upright position? I suspect some airlines set the angle at below 90 degrees…
There should also be specifications about how much distance should be left after the guy in front reclines to max, and I do not recline at all.
Someone should analyze how much that will increase the cost of tickets.
“Unbundling of Airline services” has significantly impacted Airline behaviour, but airline ticket pricing is a separate beast. We will look at this someday. Till then, have safe and comfortable air travel.
Post script: 28/Feb/2024
Notes and References:
Miami Dade Board of County Commissioners Study - Review of Studies on Passenger Seat Size on Commercial Airplanes
WSJ Article 2012: The Incredible Shrinking Plane Seat
Airbus Article 2013: Airbus Calls on Aviation Industry to Set a New Standard for Long Haul Comfort
Research Paper Delft University of Technology 2021: The effect of 17-inch-wide and 18-inch-wide airplane passenger seats on comfort
WSJ Article 2014: Skinnier Seats on More Crowded Planes
Research Paper Delft University of Technology 2017: Thirty years of anthropometric changes relevant to the width and depth of transportation seating spaces, present and future
Reuters Article Dec 2022: U.S. senators want FAA to rewrite aircraft evacuation standards
Reuters Article March 2023: U.S. court won't require FAA to make airplane seat size, spacing rules
SeatsGuru Website: Seat Dimension comparisons across airlines and ticket classes.
Article 2012: Too fat to fly? Obesity and aircraft seating