The use of the terms together seems an oxymoron. Passenger comfort in coach class is notoriously missing, despite the best efforts of the OEMs to design cabins that restore it.
As any passenger knows, it’s the airlines that ultimately decide the seating configuration. Interestlingly, the UK is the only country that has regulations defining the minimum size of passenger seats and the space between seats.
Boeing designed the 787 with comfortable eight abreast seating in mind and airlines immediately chose to narrow the seating and cram in nine abreast. The 777 was intended to have nine and airlines chose 10. None of this speaks to seat pitch.
Airbus, at its recent Innovation Days event spent significant time explaining how its cabin design team is offering the industry’s widest seats.
Even as Airbus touts these wider seats, reality among airlines is something different. Researching at SeatGuru.com, we discovered that many Airbus customers do not make use of the OEM’s offerings. We included data for the 737 for comparison purposes. The following table listing seat widths on typical single aisle airplanes in service.
The highlighted cells show the most common economy seat size for each aircraft type. Airbus A320-family airplanes seem, on average, to have a slight edge in seat width.
As one considers the table above, note in the last column the number of sub types within each airplane type. Airlines have a plethora of seating layouts within each type. The Airbus offerings may be more numerous as their cabin is wider, offering more customization as a result.
Among these airplanes, 34% of A319s, 89% of A320s, 87% of 737-700s and 83% of 737-800s have seats narrower than 18 inches. This appears to indicate that even when Airbus offers the ability to provide passengers with higher comfort levels, airlines are less enthusiastic.
Airbus now offers a new coach seating option with two 17-inch seats and a 20-inch seat at the aisle. One would think a seat that is nearly 
18% wider would be an attractive ancillary revenue opportunity for airlines. Airbus suggests the ancillary revenue could be worth over $3m NPV over 15 years. We will see if the idea takes off. The challenge for airlines is integrating this new concept into an existing fleet.
Unfortunately, when offering the 20-inch seat (on the aisle) the other two seats go to 17-inch width. Which means that if deployed, one third of passengers get the more comfortable seat and two thirds go back to 17-inch width compared to today’s 18-inch width. Airbus argues that offering the wider seat actually means more comfort for the other two seats as there is a sense of much less crowding. As Airbus puts it: “Providing adequate seat width for those that need it most, improves the travel experience for those sitting close by.” Of course the argument is bolstered by the fact that the 17-inch seat is what is typical on competing 737s.
In linear terms, Airbus says that a one inch seat width increase is equivalent to a 1.6 inch pitch increase. As anyone in an economy seat can comprehend, those inches grow logarithmically more valuable with each 30 minute segment of flight length.
The 17 inch seat width dates back to the start of the jet age in the early 1960s. How have people changed since then? Average height has not changed; American men are about 5 feet 9 inches and American women are 5 feet 4 inches. Height speaks to seat pitch. With respect to seat width, consider this. Americans have grown a lot larger over the period and need that extra inch of seat width.
Results from the 2007–2008 National Health and Nutrition Examination Survey, using measured heights and weights, indicate that an estimated 34.2% of U.S. adults aged 20 years and over are overweight, 33.8% are obese, and 5.7% are extremely obese. Disturbing statistics for those of us living in the United States. And probably why so many Americans find airline seats growing smaller.
I suspect that LCC operators of the A320 family like the extra cabin width used in the aisle as this allows greater speed in boarding as it is far easier to pass than the more cramped 737 aisle. Also can pass by the service trolley which is nigh on impossible in a narrower aisle.
Most 777’s luckely are 9 abreast and the all around 767s also have comfortably wide seats.. On the NB there an advantages though. A 6 inch wider aisle also makes a difference on e.g high frequency city pairs, (de-) boarding LCCs.
Don’t airlines have a good amount of influence on what seats they want? In some cases the airframer have a list of suppliers, in others, the airline contracts directly with seat manufacturer’s like BE Aerospace, RECARO, ZIM Flugsitz and the like. For example, Thai signed a contract with RECARO for economy A380 seats and with ZIM Flugsitz for A330 seats.
So, when, “the 777 was intended to have nine and airlines chose 10,” does this reflect badly on the 777 rather than the airline?
So, if airlines wanted wider aisle seating wouldn’t they have asked already without Airbus marketing?
If you added a third row for Bombardier’s C Series planes it would read 19″ 100%.
http://en.wikipedia.org/wiki/Bombardier_CSeries
Bombardier is in talks with AirAsia about a more densely packed 160-seat version of its CSeries jet which means 6 abreast seating and reducing the seat size from 19″ to 16.5. This is another example where the airlines are more concerned about profits than customer comfort.