Airlines might have to reverse course on those tiny seats.

An appeals court panel declared on Friday that federal regulators must consider a petition for review on small seats. Seat sizes have been getting smaller over the years , but the Federal Aviation Administration has no requirements for measurements.

This is the case of the incredible shrinking airline seat, Judge Patricia Millett wrote in her opinion. As the average American gets bigger, seats are getting much smaller.

The nonprofit Flyers Rights Education Fund provided the court evidence that the distance between most economy seats has gone from 35 inches to 31, and some airlines go as small as 28 inches. And on top of that, seat width has gone down 1.5 inches since the early 2000s.

The advocacy group argued that those cramped conditions are not only unhealthy, they also pose safety issues during emergency exit situations.

Accordingly, when the Administration responds to a petition for rulemaking that exposes a plausible life-and-death safety concern, the Administration must reasonably address that risk in its response, the court opinion stated. The Administration failed that task here.

Flyers Rights originally petitioned the FAA in 2015, and the regulation committee dismissed the claims without providing studies that take in passenger and seat sizes into consideration.

The court isnt demanding a seat requirement, but it adds to the building momentum for a minimum size.

Rep. Steve Cohen (D-Tenn.) has put forth a second attempt to pass a bill, aptly nicknamed the SEAT Act, to regulate seat and legroom on flights. The Seat Egress in Air Travel Act has languished in the Aviation Subcommittee since March, and Cohen hopes to attach his proposal to a bill to renew the FAAs authority on Sept. 30.