United States Court of Appeals

FOR THE DISTRICT OF COLUMBIA CIRCUIT

Argued March 10, 2017 Decided July 28, 2017

No. 16-1101

FLYERS RIGHTS EDUCATION FUND, INC., D/B/A 

FLYERSRIGHTS.ORG, AND PAUL HUDSON,

PETITIONERS

v.

FEDERAL AVIATION ADMINISTRATION, ET AL.,

RESPONDENTS

On Petition for Review of an Order of 

the Federal Aviation Administration

Joseph E. Sandler argued the cause and filed the briefs 

for petitioner. 

Karen Schoen, Attorney, U.S. Department of Justice, 

argued the cause for respondents. With her on the brief were 

Benjamin C. Mizer, Principal Deputy Assistant Attorney at 

the time the brief was filed, and Mark B. Stern, Attorney.

Before: ROGERS, MILLETT, and PILLARD, Circuit Judges.

Opinion for the Court filed by Circuit Judge MILLETT.
2 

 Opinion concurring in part and concurring in the 

judgment filed by Circuit Judge ROGERS. 

MILLETT, Circuit Judge: This is the Case of the 

Incredible Shrinking Airline Seat. As many have no doubt 

noticed, aircraft seats and the spacing between them have 

been getting smaller and smaller, while American passengers

have been growing in size. Paul Hudson and the Flyers 

Rights group became concerned that this sharp contraction in 

passenger seating space was endangering the safety, health, 

and comfort of airline passengers. So they petitioned the 

Federal Aviation Administration to promulgate rules 

governing size limitations for aircraft seats to ensure, among 

other things, that passengers can safely and quickly evacuate a 

plane in an emergency. The Administration denied the 

petition, asserting that seat spacing did not affect the safety or 

speed of passenger evacuations. To support that conclusion, 

the Administration pointed to (at best) off-point studies and 

undisclosed tests using unknown parameters. That type of 

vaporous record will not do—the Administrative Procedure 

Act requires reasoned decisionmaking grounded in actual 

evidence. Accordingly, we grant the petition for review in 

part and remand to the Administration. 

I 

A 

Congress has charged the Federal Aviation 

Administration with ensuring the safety and security of 

commercial airline passengers. See 49 U.S.C.

§§ 44701, 40101(d); see also Wallaesa v. Federal Aviation

Admin., 824 F.3d 1071, 1079 (D.C. Cir. 2016). In fulfilling

that role, the Administration has “‘plenary authority to

[m]ake and enforce safety regulations governing the design
3

and operation of civil aircraft’ in order to ensure the 

‘maximum possible safety.’” Bargmann v. Helms, 715 F.2d 

638, 642 (D.C. Cir. 1983) (alteration in original) (quoting 

H.R. REP. NO. 2360, 85th Cong., 2d Sess. 2, 7 (1958)). 

As relevant here, the Federal Aviation Act charges the 

Administration with “promot[ing] safe flight of civil aircraft 

in air commerce by prescribing * * * minimum standards 

required in the interest of safety for * * * the design, material, 

construction, quality of work, and performance of aircraft,” as 

well as “regulations and minimum safety standards for other 

practices, methods, and procedure[s] * * * necessary for 

safety in air commerce[.]” 49 U.S.C. § 44701(a)(1), (5). 

When issuing such minimum safety standards and regulations, 

the Administration must consider “the duty of an air carrier to 

provide service with the highest possible degree of safety in 

the public interest[.]” Id. § 44701(d)(1)(A). In addition, the 

Administration “shall consider the following matters, among 

others, as being in the public interest: (1) assigning, 

maintaining, and enhancing safety and security as the highest 

priorities in air commerce[, and] (2) regulating air commerce 

in a way that best promotes safety and fulfills national defense 

requirements.” Id. § 40101(d)(1), (2). The Administration

thus has broad authority to promulgate regulations 

“reasonably related to safety in flight.” Wallaesa, 824 F.3d at

1079 (internal quotation marks and citation omitted).

Members of the public may petition the Administration to 

promulgate, amend, or repeal regulations. See 49 U.S.C. 

§ 106(f)(3)(A); 14 C.F.R. § 11.61(a). Such a petition must 

include, among other things, the purpose of the proposed 

action, an “explanation of why [the] proposed action would be 

in the public interest,” and “[a]ny specific facts or 

circumstances that support” the proposed action. 14 

C.F.R. § 11.71(a). Once it receives a petition, the 
4

Administration has six months to respond either “by 

dismissing such petition[], by informing the petitioner of an 

intention to dismiss, or by issuing a notice of proposed 

rulemaking or advanced notice of proposed rulemaking.” 49 

U.S.C. § 106(f)(3)(A); see 14 C.F.R. § 11.73(a), (e).

B

On August 26, 2015, Paul Hudson and the non-profit 

organization Flyers Rights Education Fund of which he is 

president (collectively, “Flyers Rights”) petitioned the 

Administration to promulgate rules governing the minimum 

requirements for seat sizes and spacing on commercial 

passenger airlines. In its petition, Flyers Rights provided 

evidence that commercial airline seat and spacing dimensions 

have steadily decreased in size over the last several decades. 

The petition noted that economy-class “seat pitch”—the 

distance between a point on one seat and the same point on 

the seat directly in front of it—has decreased from an average 

of 35 inches to 31 inches, and in some airplanes has fallen as 

low as 28 inches. Evidence in the petition further indicated 

that average seat width has narrowed from approximately 

18.5 inches in the early-2000s to 17 inches in the early- to 

mid-2010s. The petition also noted that, since the 1960s, the 

average American flyer had grown steadily larger in both 

height and girth. Flyers Rights expressed concern that the 

decrease in seat size, coupled with the increase in passenger 

size, imperiled passengers’ health and safety by slowing 

emergency egress and by causing deep vein thrombosis (a 

potentially fatal condition involving blood clots in the legs),
5

as well as “soreness, stiffness, [and] other joint and muscle 

problems.” Pet. for Rulemaking 6.

1

Accordingly, Flyers Rights asked the Administration to: 

promulgate regulations that would (i) “set[] maintenance 

standards and limit[] the extent of seat size changes [on 

commercial airlines] in order to ensure consumer safety, 

health, and comfort”; (ii) “plac[e] a moratorium on any 

further reductions in seat size, width, pitch, padding, and aisle 

width until a final rule is issued”; and (iii) “[a]ppoint an 

advisory committee or task force to assist and advise the 

[Administration] in proposing seat and passenger space rules 

and standards[.]” Pet. for Rulemaking 3.

On February 1, 2016, the Administration denied Flyers 

Rights’ petition for rulemaking. The Administration 

explained that, in addressing petitions for rulemaking, it 

weighs: “(1) [t]he immediacy of the safety or security 

concerns * * * raise[d], (2) [t]he priority of other issues the

[Administration] must deal with, and (3) [t]he resources we 

have available to address these issues.” Denial of Pet. for 

Rulemaking 1; see also 14 C.F.R. § 11.73(a). The 

Administration then concluded that Flyers Rights’ concerns 

 1 Flyers Rights is not alone in its concerns. See Press Release, 

Office of the Hon. Steve Cohen, Tenn. 9th Dist., Reps. Cohen and 

Kinzinger, Senators Blumenthal, Schumer, Markey, Menendez and 

Feinstein Introduce Bipartisan, Bicameral SEAT Act (March 9, 

2017), https://cohen.house.gov/media-center/press-releases/repscohen-and-kinzinger-senators-blumenthal-schumer-markeymenendez-and [https://perma.cc/KL7J-GE62] (last accessed July 

21, 2017) (“The average distance between rows of seats has 

dropped from 35 inches before airline deregulation in the 1970s to 

about 31 inches today. The average width of an airline seat has also 

shrunk from 18 inches to about 161⁄2.”).
6

did not warrant action because the issues raised “relate[d] to 

passenger health and comfort, and d[id] not raise an 

immediate safety or security concern.” Denial of Pet. for 

Rulemaking 2. The Administration reasoned that it already 

“require[s] full-scale evacuation demonstrations and analysis 

that set the limit for the maximum number of passengers for 

any given airplane model,” including for aircraft with

“interior configurations that are more critical (less seat pitch 

and higher number of passengers) than most configurations 

operated by the airlines,” and that emergency egress tests 

“have been successfully conducted at 28- and 29-inch 

pitch[.]” Id. The Administration added that “[s]eat pitch 

alone does not determine the amount of space available 

between seats * * * [because] modern, thinner seats at lower 

seat pitch provide more space than older seats did at higher 

pitch.” Id. The Administration further noted that the medical 

concerns identified in the petition exist “irrespective of the 

seat pitch[.]” Id. With respect to Flyers Rights’ concerns 

about deep vein thrombosis, the Administration concluded 

that the condition was “rare”; it can occur with “any longduration seated activity”; and its risks are “the same for 

economy-class and business-class.” Id. 

The Administration’s denial of the petition for 

rulemaking did not cite any studies or tests to corroborate its 

representations. Nor did it challenge Flyers Rights’

characterization of seat dimension decreases or passenger size 

increases. 

Flyers Rights sent a follow-up letter to the 

Administration’s Director of the Aircraft Certification Service

asking the Administration to “formally cite the study(ies) [it]

* * * rel[ied] on” in denying the petition. J.A. 173. In 

response, the Administration identified a series of its own 

reports on airplane emergency egress and links to medical 
7

websites that discussed deep vein thrombosis. The studies 

cited in the letter did not address the impact of smaller seat 

dimensions or increased passenger size on the ability of 

passengers to expeditiously leave their seats and reach the 

emergency exits.

Dissatisfied with the Administration’s unsubstantiated 

representations about matters of passenger health and safety, 

Flyers Rights timely petitioned this court for review. 

II

We review the Administration’s actions to determine 

whether they were “arbitrary, capricious, an abuse of 

discretion, or otherwise not in accordance with law.” Safe 

Extensions, Inc. v. Federal Aviation Admin., 509 F.3d 593, 

604 (D.C. Cir. 2007) (quoting 5 U.S.C. § 706(2)(A)). Under 

that standard, we will reverse “only if the agency’s decision is 

not supported by substantial evidence, or the agency has made 

a clear error in judgment.” Id. (citation omitted). Upon 

review, we may “affirm, amend, modify, or set aside any part 

of the order and may order the * * * Administrat[ion] to 

conduct further proceedings.” 49 U.S.C. § 46110(c).

Because Flyers Rights challenges the Administration’s 

decision not to engage in rulemaking—the Administration’s 

inaction—our review is “extremely limited.” WildEarth 

Guardians v. EPA, 751 F.3d 649, 651 (D.C. Cir. 2014)

(citation omitted); see Massachusetts v. EPA, 549 U.S. 497, 

527 (2007) (“narrow” review of agency decision not to act). 

That is because an agency has “broad discretion to choose 

how best to marshal its limited resources and personnel to 

carry out its delegated responsibilities.” Massachusetts, 549 

U.S. at 527; see also Defenders of Wildlife v. Gutierrez, 532 

F.3d 913, 919 (D.C. Cir. 2008) (“[A]n agency’s refusal to 
8

institute rulemaking proceedings is at the high end of the 

range of levels of deference we give to agency action under 

our ‘arbitrary and capricious’ review.”) (internal quotation 

marks and citation omitted).

In reviewing such decisions, we ask “whether the agency 

employed reasoned decisionmaking in rejecting the petition,”

Defenders of Wildlife, 532 F.3d at 919, and we will overturn 

the agency’s decision “only for compelling cause, such as 

plain error of law or a fundamental change in the factual 

premises previously considered by the agency,” WildEarth 

Guardians, 751 F.3d at 653 (internal quotation marks and 

citation omitted). Our review turns, more specifically, on 

whether the agency “adequately explained the facts and policy 

concerns it relied on and [whether] * * * those facts have 

some basis in the record.” Id. (alterations in original; citation 

omitted). 

III

Flyers Rights challenges two aspects of the 

Administration’s denial of its petition for rulemaking: (1) its 

conclusion that current seat pitch and width, as well as 

passenger size, do not negatively impact emergency egress, 

and (2) its denial of authority to consider matters related to 

passenger health and comfort. 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. But we disagree with Flyers Rights’ 

challenge to the Administration’s declination to regulate 

matters of physical comfort and routine health. 
9

Emergency egress

Flyers Rights’ petition for rulemaking 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. The 

petition explained why such seating constrictions could make 

it more difficult for passengers to quickly leave their seats and 

escape an aircraft in the event of an emergency. Specifically, 

the petition asserted that, in an emergency, decreased seat 

spacing would increase panic, delay access to the center aisle, 

and impede the escape of injured passengers. The petition 

also included multiple comments from airline passengers

expressing safety concerns. One commenter stated that 

current seat spacing made it “necessary to climb onto [her] 

seat to get out.” J.A. 167. Another commenter asserted that, 

given current seat spacing, “[i]n an emergency, there is no

way we would have been able to get to an exit row in less 

than three or four minutes[.]” J.A. 169.

The Administration has a broad mandate to protect and 

promote passenger safety. Ensuring that all passengers can 

rapidly evacuate an airplane is of central importance to that 

safety mission. See 14 C.F.R. § 25.803(c) (requiring that

aircraft with a capacity of more than forty-four passengers be 

capable of evacuation within ninety seconds, and that actual 

egress demonstrations be undertaken to ensure compliance 

with Administration regulations). The Administration does 

not dispute that. 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 Administration failed that task here. In asserting that 

decreasing seat size and pitch had no effect on emergency 
10

egress, the Administration pointed to certain studies and 

demonstration tests. But the cited studies 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. 

The Administration argues that the omission of 

information about seat dimensions from the tests means that 

seat dimensions are categorically unimportant to emergency 

egress. That makes no sense. Tests generally require a 

limited number of variables to be workable and verifiable. 

The omission of other variables says nothing about such 

variables’ relevance to what is being tested; it says only that 

they were not recorded, measured, or altered for that 

particular test. Take, for example, a study on tooth decay that 

only recorded 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.

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. 

Indeed, an Administration study that addressed passenger 

size in a slightly different context actually corroborates Flyers 

Rights’ point. The study considered, among other things, the 

ability of wider passengers to pass through the emergency exit 

row and door. Importantly, this test found that increased 
11

passenger width had the greatest effect on exit speed of all the 

variables tested. See J.A. 89 (chart indicating “[w]aist [s]ize” 

had the largest “[r]elative [m]agnitude of [e]ffect[]” of the ten 

variables tested). Yet nowhere did the Administration explain 

why passenger size would impede progress through the 

relatively wide emergency exit rows, yet have no impact on 

passenger movement through the far more cramped (seatpitch-decreased) seating rows.2

The Administration also overlooks that its studies are 

outdated. They were conducted in the 2000s when, according 

to the petition, seat dimensions were larger. Agency 

reasoning, however, must adapt as the critical facts change. 

See American Horse Prot. Ass’n v. Lyng, 812 F.2d 1, 5 (D.C. 

Cir. 1987) (“[A] refusal to initiate a rulemaking naturally sets 

off a special alert when a petition has sought modification of a 

rule on the basis of a radical change in its factual premises.”).

The Administration points out that evacuation tests must

be run with the maximum allowable passenger occupancy for 

any given aircraft model. See 14 C.F.R. § 25.807(g) 

(regulating the number of passengers allowed in each 

specified aircraft model to promote emergency egress); id. 

§ 25.803(c) (tests must be run with maximum allowable 

occupancy). The problem for the Administration is that 

maximum occupancy is not an adequate proxy for cabin-seat 

or passenger dimensions. Because planes commonly include 

different seating classes like first class, business class, and 

 2 A second study in part examined the impact of passenger 

size on injuries sustained when traveling through the emergency 

exit door. Notably, that study observed that “physical 

characteristics (gender, age, waist size, height) [were] previously 

shown to significantly affect emergency egress[.]” J.A. 39.
12

economy plus, limiting the number of seats in an aircraft does 

not limit seat pitch and width in all of the seats, and especially 

in the ordinary economy-class seats. That means that 

economy-seating pitch could decrease to levels that could 

impede emergency egress, while the pitch and width in the 

first class and business class seats would not. 

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. The problem is that not one of those tests is in the 

record. So they provide no evident support for the 

Administration’s conclusion. 

The Administration says they were omitted because the 

tests are “proprietary.” Administration’s Br. 13. Of course, 

an agency may decline to include confidential business 

information in the public administrative record in certain 

narrow situations, as long as it discloses as much information 

publicly as it can. See MD Pharm., Inc. v. Drug Enforcement 

Admin., 133 F.3d 8, 13 (D.C. Cir. 1998) (upholding an 

agency’s decision not to include confidential business 

information in the public record of a licensing hearing); cf. 

Mead Data Central, Inc. v. United States Dep’t of the Air 

Force, 566 F.2d 242, 260 (D.C. Cir. 1977) (Under the 

Freedom of Information Act, “[i]t has long been a rule in this 

Circuit that non-exempt portions of a document must be 

disclosed unless they are inextricably intertwined with exempt 

portions.”).

The problem here is that the Administration has given no 

reasoned explanation for withholding the tests in their 

entirety, and it has declined to file them under seal or in 

redacted form. Yet the Administration explicitly relied on

those missing studies in reaching its decision to deny the 
13

petition for rulemaking. See Denial of Pet. for Rulemaking 2

(“Full scale evacuation tests on widely used airplanes have 

been successfully conducted at 28- and 29-inch pitch[.]”);

J.A. 178. And the Administration asks the court to trust those 

studies in reviewing the Administration’s decision. See Oral 

Arg. Tr. 29–33; Administration’s Br. 11–13.

But that is not how judicial review works. We cannot 

affirm the sufficiency of what we cannot see. “[A]n agency 

decision based on ‘reliable data reposing in the [agency’s] 

files’” but hidden from judicial view “simply cannot 

withstand scrutiny.” United States Lines, Inc. v. Federal 

Maritime Comm’n, 584 F.2d 519, 535 (D.C. Cir. 1978).

Indeed, we have long held that, when “the data relied on 

by [an agency] in reaching its decision is not included in the 

administrative record and is not disclosed to the court[,]” we 

cannot “determine whether the final agency decision reflects 

the rational outcome of the agency’s consideration of all 

relevant factors[.]” United States Lines, 584 F.2d at 533

(footnote omitted). Whatever deference we generally accord 

to administrative agencies, “we will not defer to a declaration 

of fact that is ‘capable of exact proof’ but is unsupported by 

any evidence.” McDonnell Douglas Corp. v. United States

Dep’t of the Air Force, 375 F.3d 1182, 1190 n.4 (D.C. Cir. 

2004) (citation omitted).

3

 

 3

 See also Safe Extensions, 509 F.3d at 605 (“[A]n agency’s 

‘declaration of fact that is capable of exact proof but is unsupported 

by any evidence’ is insufficient to make the agency’s decision nonarbitrary.”) (citation omitted); cf. Chamber of Commerce of U.S. v. 

SEC, 443 F.3d 890, 899 (D.C. Cir. 2006) (for an informal 

rulemaking, “[a]mong the information that must be revealed for 
14

The problems with the Administration’s position do not

stop there. Even with respect to its unseen tests, the agency 

cannot say whether those tests accounted for increased 

passenger size, which is a critical component of the egress 

problem raised by Flyers Rights’ petition. When questioned 

at oral argument, counsel for the Administration was unaware 

whether such tests take into account larger passengers. See

Oral Arg. Tr. 29, 33–34.

To be sure, the record needed to support an agency’s 

decision not to engage in rulemaking can be sparser than that 

needed to support rulemaking. Normally, it “need only 

include the petition for rulemaking, comments pro and con 

where deemed appropriate, and the agency’s explanation of 

its decision to reject the petition.” WWHT, Inc. v. FCC, 656 

F.2d 807, 818 (D.C. Cir. 1981). 

But this case is different because the Administration 

admits it relied materially on information it has not disclosed, 

and the Administration has pointed this court to that 

information as a basis for affirmance. Having invited the 

court into its record, the Administration cannot hide the 

evidentiary ball. Cf. CTS Corp. v. EPA, 759 F.3d 52, 64 

(D.C. Cir. 2014) (“It is black-letter administrative law that in 

an [Administrative Procedure Act] case, a reviewing court 

should have before it neither more nor less information than 

did the agency when it made its decision.”) (alteration in 

 

public evaluation are the technical studies and data upon which the 

agency relies”) (internal quotation marks and citation omitted).
15

original; internal quotation marks and citation omitted). To 

do otherwise would reduce judicial review to a rubber stamp.

4

In short, when an agency denies a petition for 

rulemaking, the record can be slim, but it cannot be vacuous. 

Especially so when, as here, the petition identifies an 

important issue that falls smack-dab within the agency’s 

regulatory ambit. While we do not require much of the 

agency at this juncture, we do require something. And 

information critically relied upon by the agency that no one 

can see does not count. We accordingly remand to the 

Administration to adequately address the petition and the 

emergency egress concerns it raises. If the petition for 

rulemaking is again denied, the Administration must provide 

appropriate record support for its decision.

5

 

 4 See WildEarth Guardians, 751 F.3d at 653 (a reviewing 

court must determine “whether the agency adequately explained the 

facts and policy concerns it relied on and [whether] * * * those 

facts have some basis in the record”) (alterations in original; 

emphasis added; internal quotation marks and citation omitted); 

American Radio Relay League, Inc. v. FCC, 524 F.3d 227, 238 

(D.C. Cir. 2008) (“Allowing such omissions in data and 

methodology may ma[ke] it impossible to reproduce an agency’s 

results or assess its reliance upon them.”) (alteration in original; 

internal quotation marks and citation omitted); Air Prods. & 

Chems., Inc. v. FERC, 650 F.2d 687, 699 (5th Cir. 1981) (noting 

that “official notice of unspecified information in the files of an 

agency precludes effective judicial review”).

5

 See generally Florida Power & Light Co. v. Lorion, 470 

U.S. 729, 744 (1985) (“If the record before the agency does not 

support the agency action, if the agency has not considered all 

relevant factors, or if the reviewing court simply cannot evaluate 

the challenged agency action on the basis of the record before it, the 
16

Flyers Rights asks the court to go further and order the 

Administration to institute rulemaking. That we will not do. 

“Our cases make clear * * * that such a remedy is appropriate 

only ‘in the rarest and most compelling of circumstances.’” 

American Horse Prot., 812 F.2d at 7 (quoting WWHT, 656 

F.2d at 818). Rather, remand is the presumptive remedy

when the agency record is insufficient “to permit [the court] 

to engage in meaningful review.” See id. (internal quotation 

marks and citation omitted). Because the Administration 

claims to have access to the information that would fully 

justify its denial of the petition for rulemaking, an order to 

engage in rulemaking is unwarranted at this point. 

Health and comfort concerns

Flyers Rights also objects to the Administration’s failure 

to address its concerns regarding passenger health and 

comfort. More specifically, Flyers Rights’ petition worried 

that cramped seat conditions cause deep vein thrombosis, 

“soreness, stiffness, [and] other joint and muscle problems[.]” 

Pet. for Rulemaking at 6. The Administration rejected such 

concerns partly on the ground that they “relate to passenger 

health and comfort, and do not raise an immediate safety or 

security concern.” Denial of Pet. for Rulemaking 2.

Flyers Rights argues that the Administration’s failure to 

consider matters of passenger health and comfort is a 

misinterpretation of its statutory authority, pointing to 

assorted statutory provisions that purportedly require

consideration of “the availability of a variety of adequate, 

 

proper course, except in rare circumstances, is to remand to the 

agency for additional investigation or explanation.”).
17

economic, efficient[,] and low-priced services” and the

“develop[ment] and maint[enance of] a sound regulatory 

system that is responsive to the needs of the public.” Flyers 

Rights’ Opening Br. 26 (emphasis omitted) (quoting 49 

U.S.C. § 40101(a)(4), (7)). The problem for Flyers Rights is 

that the cited statutory provisions apply only to the Secretary 

of Transportation, not to the Administration. See 49 U.S.C. 

§ 40101(a). 

Flyers Rights also points out that “health” is a component 

of “safety”—a criterion the Administration without a doubt 

must consider under applicable statutory provisions. Flyers 

Rights’ Reply Br. 7–9; see Flyers Rights’ Opening Br. 26–27. 

See also 49 U.S.C. §§ 44701, 40101(d). We agree. We have

held that the Administration’s statutory authority “embod[ies] 

a comprehensive scheme for the regulation of the safety 

aspect[s] of aviation[.]” Bargmann, 715 F.2d at 642 (internal 

quotation marks and citation omitted). That includes 

protecting passengers’ physical health in flight, even from 

harms that are not occasioned by the flight. Indeed, in

Bargmann, we rejected the Administration’s position that its 

authority was confined to addressing only those health issues 

that were “caused or induced by flight.” Id. at 640 (emphasis 

and internal quotation marks omitted). We held instead that 

the Administration has the authority to regulate first aid kits 

for treating conditions that occur during the flight, whether or 

not those conditions are caused by flight conditions or 

operations. Id. at 642; see also Wallaesa, 824 F.3d at 1080 

(reaffirming the Administration’s power to regulate “care for 

ill passengers”). 

So there is no question that the Administration has the 

statutory authority to address at least some passenger health

issues. See Wallaesa, 824 F.3d at 1079–1080 (Administration 

may regulate medical equipment to ensure “‘the personal 
18

safety of the stricken passengers’ and crew”) (citation 

omitted); Bargmann, 715 F.2d at 642–643 (“Not only are 

inflight medical emergencies of immediate concern to the 

personal safety of the stricken passengers, but they may also 

be of concern to the safety of others.”) (citation omitted); 14 

C.F.R. § 121, App. A (Administration regulation requiring 

“automated external [heart] defibrillator[s]” on passenger 

aircraft).

6

The problem for Flyers Rights is that, in this case, the 

Administration acknowledged its authority to protect the 

health of passengers, stating that it would “continue to 

monitor seat designs and effects on safety and health.” J.A. 

175 (emphasis added). The Administration thus did not 

 6 The concurring opinion would hold that Flyers Rights 

waived reliance on the Bargmann line of cases. Concurring Op. 1–

3. We respectfully disagree. Flyers Rights pressed the argument 

that passenger health can be regulated in conjunction with safety in 

its opening brief. See Flyers Rights’ Opening Br. 26–27; Flyers 

Rights’ Reply Br. 7–9; Pet. for Rulemaking 3. To be sure, the 

manner in which Flyers Rights substantiated that argument evolved 

from its opening to reply brief. But that is not an uncommon 

occurrence. What matters is that the core of Flyers Rights’ 

argument—that passenger health can be regulated in conjunction 

with safety—remained the same. And once an argument is before 

us, it is our job to get the relevant case law right. Cf. Elder v. 

Holloway, 510 U.S. 510, 516 (1994) (when deciding a “question of 

law,” a court “should * * * use its full knowledge of its own [and 

other relevant] precedents”) (second alteration in original; internal 

quotation marks and citation omitted); United States v. Rapone, 131 

F.3d 188, 196–197 (D.C. Cir. 1997). Indeed, a party cannot forfeit 

or waive recourse to a relevant case just by failing to cite it. See 

Elder, 510 U.S. at 514–516; Metavante Corp. v. Emigrant Sav. 

Bank, 619 F.3d 748, 773 n.20 (7th Cir. 2010). 
19

decline to regulate the types of circulatory harms identified by 

Flyers Rights because it thought it could not address such 

matters. Rather, the Administration decided that it should not 

address those issues at this time, making the very type of 

regulatory-effort and resource-allocation judgments that fall 

squarely within the agency’s province. 

Specifically, with respect to the risk of deep vein 

thrombosis, the Administration cited evidence showing that it 

rarely occurs and, regardless, is not caused by seat size or 

spacing. See Denial of Pet. for Rulemaking 2; J.A. 176

(citing a study noting that guidelines issued by the American 

College of Physicians indicate that deep vein thrombosis is 

“extremely rare” and that risk of deep vein thrombosis is not 

any higher in economy class than business class) (citation 

omitted). Thus, the Administration reasonably declined to 

initiate rulemaking to assess Flyers Rights’ concerns about 

deep vein thrombosis.

Flyers Rights also noted passenger problems with 

“soreness, stiffness, [and] other joint and muscle problems” in 

its petition for rulemaking. Pet. for Rulemaking 6. Given that 

those conditions are commonplace, temporary, and non-lifethreatening discomforts, Flyers Rights’ petition failed to 

demonstrate that the Administration erred in declining to 

undertake immediate rulemaking.7

 7 Flyers Rights appears to have abandoned its argument that 

the Administration must consider passenger comfort when issuing 

regulations. In any event, the Administration reasonably concluded 

that matters pertaining exclusively to passenger “comfort” are not

within its regulatory wheelhouse. See 49 U.S.C. §§ 44701(a), 

40101(d). 
20 

* * * * *

We grant Flyers Rights’ petition for review in part, and

remand to the Administration for 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. We otherwise deny the 

petition for review. 

So ordered. 
ROGERS, Circuit Judge, concurring in part and concurring

in the judgment: I join the court in remanding this matter to the

Federal Aviation Administration (“FAA”) to address adequately

the petition for rulemaking filed by Paul Hudson and the Flyers

Rights Education Fund (“petitioners”) with respect to concerns

about emergency egress from airplanes in light of decreases in

seat size and pitch. See Op. 9–16. I also join the court in

rejecting petitioners’ argument that 49 U.S.C. § 40101(a)

required the FAA to consider matters of passenger health and

comfort. See Op. 16–17. Unlike the court, however, I would

decline to reach petitioners’ additional argument, first raised in

their reply brief, that the concept of “safety” in 49 U.S.C.

§ 44701(a), a term that is not statutorily defined, “inherently

includes and is intertwined with the health of passengers.” 

Reply Br. 8. But see Op. 17–19. 

The court does not usually address arguments first raised in

a reply brief, treating them as “waived,” in order to “prevent

sandbagging of appellees and respondents.” CTS Corp. v. EPA,

759 F.3d 52, 60 (D.C. Cir. 2014) (quoting Novak v. Capital

Mgmt. & Dev. Corp., 570 F.3d 305, 316 n.5 (D.C. Cir. 2009));

see United States v. Van Smith, 530 F.3d 967, 973– 74 (D.C. Cir.

2008) (citing cases and FED. R. APP. P. 28(c)). This, of course,

is not to say that the court should disregard refinements made in

a reply brief to an argument properly raised in an opening brief. 

Here, however, petitioners have offered two distinct theories,

based on different statutory provisions, for how the FAA

misconstrued the scope of its statutory authority in dismissing

passenger health and comfort concerns in responding to the

petition for rulemaking — one in their opening brief and the

other in their reply brief.

Petitioners contend in their opening brief that the FAA

misconstrued its authority by refusing to consider passenger

comfort and safety “because it interpreted its own statutory

mandate to be limited to safety concerns.” Pet’r Br. 26. 

Although they acknowledge the FAA’s safety responsibilities
2

under Section 44701(a), petitioners do not rely on this provision

for their argument and instead maintain that the FAA has

statutory duties distinct from its safety responsibilities that

require it to consider passenger health and comfort, citing

Sections 40101(a)(4) & (7). See id. at 26–27. Specifically,

petitioners state in their opening brief: “To be sure, the FAA

has a statutory responsibility to ‘promote safe flight of civil

aircraft in air commerce.’ 49 U.S.C. § 44701(a). But it also has

a responsibility, in regulating the industry, to consider a number

of other factors . . . .” Pet’r Br. 26 (emphasis added). 

Petitioners then cite various obligations under Section 40101(a)

that require consideration of the needs and interests of the

public, and contend that these provisions create a “clear

statutory command” to consider passenger health and comfort

concerns. Id. at 26–27 (quoting Massachusetts v. EPA, 549 U.S.

497, 533 (2007)). In petitioners’ view, “the FAA believed,

incorrectly, that it was not legally obligated even to consider the

‘needs of the public’ with respect to passenger health and

safety,” id. at 27, quoting Section 40101(a)(7).

Thus, it is evident that in their opening brief petitioners

conceived of health and safety as distinct factors, with the

FAA’s corresponding health obligations arising under different

statutory provisions than its safety responsibilities under Section

44701(a). Only after the FAA pointed out in its responsive brief

that Section 40101(a), on which petitioners relied in their

opening brief, applies to the Secretary of Transportation rather

than the FAA, see Resp’t Br. 19, did petitioners raise in their

reply brief the additional argument that “health” is a component

of “safety” under Section 44701(a), Reply Br. 8. As presented

by petitioners in their briefs to this court, one statutory theory is

not “baked into” the other. The FAA responded in its brief to

the only theory presented in petitioners’ opening brief and had

no opportunity to respond in its brief to petitioners’ second

theory presented for the first time in their reply brief. Stepping
3

in, the court offers its own view on how the FAA construes its

own authority under Section 44701(a), without the benefit of

briefing from the FAA on this question. See Op. 18–19. 

Petitioners offer no explanation for their failure to raise both

arguments in their opening brief, none is apparent from the

record, and no extraordinary circumstances excuse their failure

to do so. The court seeks to avoid our precedent by suggesting

that petitioners’ statutory argument simply “evolved” in their

reply brief, Op. 18 n.6, but references to arguments presented in

the rulemaking petition to the FAA, see id., that petitioners did

not, in fact, raise in their opening brief does not eliminate the

“sandbagging” of the FAA that has occurred on appeal. After

all, litigants may have several reasons to think an agency has

erred, but they make choices about which arguments to present

on appeal; opposing parties in filing a responsive brief

legitimately confine their response to the arguments presented

in the opening brief. It is hardly common practice to ignore

whether the opposing party has notice of the other party’s

position, but see id., and this court has tended to take a strict

view of the obligation on appealing parties to set forth their

arguments in their opening briefs, see, e.g., Am. Wildlands v.

Kempthorne, 530 F.3d 991, 1001 (D.C. Cir. 2008); Van Smith,

530 F.3d at 973–74 (citing cases). Consequently, in accordance

with the court’s precedent, I would not reach the new statutory

theory presented only in petitioners’ reply brief.