The solution
In April 2017 WIRED covered Optima, a patented seating system shown by aviation design studio Acumen at the Aircraft Interiors Expo in Hamburg. It is a twist on the herringbone layout used in business class by airlines such as American, Virgin Atlantic and Qatar Airways.
In Optima, seats A and B sit next to each other facing straight ahead with a privacy screen between them, flanked ahead and behind by rows where seats C and D angle away from the centre. When lying flat, the passengers in A and B slide their feet under the side tables of neighbours C and D. Every passenger keeps aisle access, a lie-flat seat and sightlines that do not meet strangers', in a cabin packed tighter than usual.
Why it worked
Interlocking footwells use space that herringbone layouts leave empty.
Passengers still get aisle access and privacy, so the denser cabin does not feel worse to each of them.
A generic version lets any airline buy it with its own stowage and privacy options, not just a single customer.
What can be applied
Pack more units in by letting each one's awkward part borrow space from a neighbour's, not by shrinking anyone.
Aftermath
WIRED noted that Acumen had worked with United on its Polaris seating system, which uses a similar configuration but is exclusive to United, while Optima is offered to anyone. New seats take years to design, test and certify, and no airline order for Optima was reported in the article.
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