Everybody complains about sharing airplane armrests, but Michael Batt is trying to do something about it. Considering that no one likes the middle seat anyway, why not sell it as two half seats that occupiers of the aisle and window seats can share?
"There are a lot of people who would pay not to touch elbows with somebody else," said Batt, who flies up to 250,000 miles as year as founder and co-chairman of Travel Leaders Group, an $18 billion corporate travel agency. "They won't buy a whole [second] seat because it seems extravagant, but they might pay a premium for a half-seat."
(Read more: Virgin Atlantic stand-up takes flight)
At a time when airlines are rolling out increasingly opulent options for those sitting up front, Batt's suggestion is just one of several proposals to make the term "comfortable coach seat" something other than an oxymoron.
"It's one of those problems that a lot of people are taking on as a design challenge," said Rob Green, a senior design engineer at Dyson. "You have to balance the ergonomics—making sure it's comfortable—with getting as many people on board in the smallest amount of space."
It's safe to say that most passengers are fairly certain the balancing act, at least in coach, is in serious need of recalibration.
Enter folks like Alireza Yaghoubi, who as an engineering student in Malaysia won a James Dyson Award last year for his AirGo seat, which aims to protect your personal space even when the passenger in front of you threatens to recline his or her seat into your face.
To accomplish that, AirGo substitutes elastic, form-fitting fabrics for bulky cushions and uses three motors that provide more recline with less intrusion. Add telescoping tray tables and TV screens on articulated arms, and the result looks like a cross between a Nautilus machine and something out of "Star Wars."
Yaghoubi is applying for a patent for his design.
There's also the Side-Slip Seat from Denver-based Molon Labe Designs. In this three-across seating system, the aisle seat slides partway over the middle seat during boarding.
The Side-Slip's creator, retired Navy test pilot Hank Scott, said the action expands the typical airplane aisle to 43 inches from 19, easing one of the' biggest frustrations for fliers and fostering faster turnaround for carriers.
The system requires that the middle seat be set slightly lower and back from the rest of the row, which adds two benefits: staggered positioning for passengers' shoulders and a middle seat that can be up to three inches wider.
"Your shoulders are further forward or further back, so the elbow space you're going for is not the same elbow space they're going for," Scott said. And while the wider middle seat doesn't provide any extra legroom, it addresses the real issue of airplane crowding.
"Everybody talks about seat pitch but they don't pay attention to width," he said. "We're not getting taller—we're getting wider."
(Read more: San Diego airport expands, gets greener)
Needless to say, you probably won't find the AirGo or Slip-Seat on your next flight. But for Green, they're part of a larger trend in which new materials and ideas are allowing airline cabin designers to rethink passengers' living space.
Airlines including Alaska and United, for example, are getting ready to roll out planes with seats that feature a slimmer profile and more ergonomic design than their predecessors. According to the manufacturer, Recaro Aircraft Seating, they provide more comfort and the potential for up to an extra inch of legroom.
(Read more: Atlanta's gun-carrying fliers)
The real question, of course, is what individual airlines decide to do with that extra space.
"If the seats are half as thick, you can create quite a lot of additional space," Green said. "Now, whether that means they just stick another row of seats in or they give each passenger more space, I don't know. I suspect they'll try to get another row of seats in."
–Rob Lovitt is a longtime travel writer who still believes the journey is as important as the destination. Follow him on