More than 10,000 examples may have been built, but the Boeing 737’s cabin dimensions – save for changes in fuselage length as variants and new-generation families arrived – have not altered since the narrowbody entered service 50 years ago. That original Lufthansa 737-100 from 1968 shares the same 3.54m cabin cross-section as the Max variants being delivered today.

However, half a century of design evolution means the cabin of the late 1960s is as different from today’s interior as the clothes and hairstyles of the passengers who sat in it. And it is why – despite limitations of shape – Boeing designers believe is still much that can be done to the interior of the 737 and Boeing’s other types to make passengers more comfortable and content without compromising on airline demands to have an asset that is profitable to operate.

Boeing is not planning any announcements at Hamburg – its next big reveal will be cabin concepts for the 777X this year. But, aside from being at AIX to talk to airlines and interiors suppliers, it is keen to share talk about its efforts to, as payloads chief architect PJ Wilcynski puts it, “make the available space seem more spacious, increase comfort without reducing seats, and making the interior more adaptable”. It has revealed a number of artist’s impressions of concepts that could be appearing in 737 cabins in the near future.

These include a touchscreen for flight attendants to control the cabin environment, replacing the panel of switches and buttons, an “immersive cabin lighting” system that can project images on to the ceiling, such as a real-time representation of the sky above the aircraft, and a wingtip camera that allows passengers in window seats to use seatback screens to take “selfies” of themselves looking out.

Boeing’s last major cabin revamp for the 737 was the Sky Interior, launched on the NG at the turn of the decade and featuring sculpted sidewalls, redesigned windows to appear larger, LED lighting, pivot bins, and improved passenger service units. Almost all 737NGs delivered after 2012 had the Sky Interior installed and the concept was retained for the Max, which went into service last year.

Kent Craver, regional director cabin experience and revenue analysis, points to research that Boeing conducted with Norwegian around 2012 – shortly after the first 737NGs with the Sky Interior went into service with the Scandinavian low-cost carrier – to illustrate how.

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“When we surveyed passengers who flew in a standard NG interior and others who flew with the Sky Interior, despite the airplanes design changes can alter passenger perceptions of spaciousness and wellbeing, even when aspects of the product have not changed.having the exact same configurations, on every question we asked those on the Sky Interior rated it better – significantly better,” he says. “They thought the lavs were bigger, the seats were easier to sleep in, even that the food was better. They believed the aircraft was wider, the ceiling higher and the windows bigger.”

Even those sitting in 29in-pitch seats in the Sky Interior rated their comfort higher than those in 31in seats in the older cabin, says Craver. “It shows how the sense of spaciousness can override the physical,” he says.

For years, Boeing has been making the point that there is no direct correlation between seat width and perceived passenger comfort on widebodies. Most Airbus A350s are equipped with nine-abreast 18in seats in economy, while most A330s are eight-abreast. The most common configuration selected for the 787 is nine-abreast 17.1in seats. Craver dismisses Airbus research findings that maintain that its wider seats allow passengers to sleep better.

“Seat width is a poor predictor of passenger comfort and surveys bear that out,” he says. “Our competitor’s sample size on that survey was less than 10. We sample thousands [of passengers] and have found that the nine-abreast 787 beats the eight-abreast A330 in terms of perceived passenger comfort. Sure, if everything else is equal, people will prefer a wider seat, but things are far from being equal, and on the 787 we are often talking half an inch [of seat width]. Most people don’t even notice.”

He adds: “If you ask a passenger would they like a wider seat, they will of course say yes, just as they would say they want more legroom, more channels, better food. But the question becomes: what are you willing to pay? There is a subset that will pay for added space, and that is why we have premium economy, but it’s not for everyone. The overwhelming majority [of economy passengers] want a really low ticket price.”

Source: Flight Daily News