A federal appeals court has ordered the Federal Aviation Administration to reconsider a petition filed by consumer advocates seeking to halt the ever-decreasing size of airline seating arrangements.

In Aug. 2015, the organization Flyers Rights filed a petition with the FAA, calling on the agency to issue new rules halting the further reductions in both the size of airplane seats and seat “pitch” — the distance between rows of seats.

This isn’t just a matter of tall travelers knocking their knees on seat backs, or heavier fliers feeling the pinch of too little room between the armrests. Seat width and pitch are matters of passenger safety and health, argued the Flyers Rights petition.

“[F]lying can cause potentially life threatening blood clots from lack of movement and cramped spaces,” wrote the group. “Deep vein thrombosis (DVT), also known as ‘economy-class syndrome,’ occurs when leg clots develop in deep veins. This happens when one’s legs are not moving and the muscles are not contracting. Medical professionals suggest moving about the cabin or performing different leg exercises while seated. The issue with this suggestion is many people do not have the room to move in their seat or get up to move about the cabin. Reducing the seat space even more would only expand the issue and cause greater health, safety, and comfort concerns.”

With regard to safety, the petition claims out that while the FAA requires airlines to test their emergency evacuation plans under realistic circumstances (including randomly blocked exits and low light conditions) these tests are not being run on any aircraft with seat pitches narrower than 31 inches. But some planes now have pitches that go as low as 28 inches. Those few inches may make a significant difference, according to Flyers Rights, particularly as your typical traveler grows larger.

“Additionally, these FAA required emergency evacuation tests to not factor in human panic, such as older passengers, passengers with children, or passengers with disabilities who may need more time to evacuate,” explains the petition. “A decreased amount of space between seats would likely increase this panic, and cause delays in evacuations during an emergency.”

The petition asked the FAA to pause further reductions in seat width or pitch, and to create a new regulation establishing minimums for these dimensions.

Thanks, But No

Not only is the public allowed to petition the FAA to create or revise regulations, federal law requires that the FAA consider that petition within six months and then provide a written explanation of its response, regardless of what the decision is.

So in Feb. 2016, the FAA replied [PDF] to the Flyers Rights petition, effectively brushing off the group’s concerns.

The rules for considering a petition direct the FAA to look at three criteria, including “The immediacy of the safety or security concerns raised.” The petition failed, explained the FAA, because the concerns raised by Flyers Rights “relate to passenger health and comfort, and do not raise an immediate safety or security concern.”

Additionally, the FAA said that, contrary to the claims in the petition, “Full scale evacuation tests on widely used airplanes have been successfully conducted at 28- and 29-inch pitch,” and that “Seat pitch alone does not determine the amount of space available between seats. The seat design will play an important role. In general, modern, thinner seats at lower seat pitch provide more space than older seats did at higher pitch.”

As for the petitioner’s concerns about deep vein thrombosis, the FAA counters that the risk of DVT “is the same for economy-class and business-class travel.”

Show Us Your Work

Though the FAA’s denial letter referenced a number of tests and studies, the agency didn’t actually cite specific research or provide any details to corroborate its assertions. So Flyers Rights responded to the letter, asking the FAA to provide the evidence it used to reject the petition.

The FAA ultimately responded, listing three of its own reports on passenger evacuation. But none of this impressed the Flyers Rights folks, who say the three FAA studies “focused primarily on exit row seating,” and this research did not “report on the results of any evacuation test conducted with seat configurations of any specified width or seat pitch.”

Rather than continue this back-and-forth with the FAA, Flyers Rights took its petition to the Court of Appeals for the D.C. Circuit, which has the authority to review the agency’s decision.

Do It Again

Last week, the D.C. Circuit ruled in favor of Flyers Rights, telling the FAA to put a little more thought into its consideration of the petition.

“We agree with Flyers Rights that the Administration failed to provide a plausible evidentiary basis for concluding that decreased seat sizes combined with increased passenger sizes have no effect on emergency egress,” explains Judge Patricia Millett in the court’s opinion [PDF], which she dubbed “the Case of the Incredible Shrinking Airline Seat.”

The appeals panel found that Flyers Rights had “reasonably identified a safety concern arising from the commercial airlines’ documented pattern of placing ever larger passengers in ever smaller seats with still less space between them,” and that when the FAA is faced with a “plausible life-and-death safety concern,” it “must reasonably address that risk in its response… The Administration failed that task here.”

The judges took issue with the studies cited in the FAA’s follow-up response, noting that these reports “say nothing about and do not appear to control for seat pitch, width, or any other seat dimension. Nor do they address or control for how increased passenger size interacts with the current seat dimensions to affect emergency egress. Studies cannot corroborate or demonstrate something that they never mention or even indirectly address.”

These studies didn’t include data on seat dimensions because it’s not important to emergency egress, argued the FAA, but the appeals court called shenanigans on this way of thinking.

Millett gives the theoretical example of a study on tooth decay that only kept track of participants’ sugar consumption.

“The study’s silence on the question of brushing and flossing would surely not imply that brushing and flossing have no effect on the risk of getting a cavity,” she writes. “The Administration’s rationale also blinks reality. As a matter of basic physics, at some point seat and passenger dimensions would become so squeezed as to impede the ability of passengers to extricate themselves from their seats and get over to an aisle. The question is not whether seat dimensions matter, but when.”

In fact, the court points out, one of the FAA exit row studies that it used to back up its denial of the petition includes data that would seem to support Flyers Rights’ assertion that passenger size (and therefore seat dimensions) are a safety factor.

This chart shows that “Subject waist size” had the greatest effect on an individual test subject’s ability to leave through the exit row:

The court chided the FAA. If passenger size is such a factor in a relatively wide exit row, how can the agency make the claim that it is not relevant to passengers seated in other rows with less space to move about?

“Finally, the Administration stated in its decision that emergency evacuation tests have been successfully run with seat dimensions as small as those being used by commercial airlines,” notes Millett. “The problem is that not one of those tests is in the record.”

The FAA, claiming these tests are “proprietary,” refused to provide the seat dimension data to the court, even under seal or redacted to remove sensitive information.

“But that is not how judicial review works,” counters the court. “We cannot affirm the sufficiency of what we cannot see.”

What Now?

The court’s ruling doesn’t mean that the FAA has to grant Flyers Rights petition. In fact, given the current deregulatory approach in D.C., it’s highly unlikely the agency would grant this petition.

Instead, the agency has been instructed to provide a “properly reasoned disposition of the petition’s safety concerns about the adverse impact of decreased seat dimensions and increased passenger size on aircraft emergency egress.” In other words, it has to more thoroughly make its case why it should continue to ignore the problem of seat width and pitch.

However, the FAA may soon have no choice in addressing this matter. In June, Rep. Steve Cohen (TN) successfully got an amendment tacked on to the FAA reauthorization bill that would effectively require the agency to do the same thing as in the petition: finally establish minimum seat dimensions.

And again, there is always the possibility that the FAA could set minimums that are even narrower than current low-end dimensions, so let’s not get too excited; it’s going to be a bumpy flight.

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