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United States Court of Appeals 

FOR THE DISTRICT OF COLUMBIA CIRCUIT

Argued September 22, 2021 Decided December 28, 2021 

No. 20-1443 

CHARLES ERWIN, 

PETITIONER

v. 

FEDERAL AVIATION ADMINISTRATION, 

RESPONDENT

On Petition for Review of an Order 

of the Federal Aviation Administration 

Joshua D. Burns argued the cause for petitioner. On the 

briefs was D. Michael McBride III.

Casey E. Gardner, Attorney, Federal Aviation 

Administration, argued the cause and filed the brief for 

respondent. 

Before: HENDERSON, TATEL and WILKINS, Circuit Judges. 

Opinion for the Court filed by Circuit Judge HENDERSON. 
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KAREN LECRAFT HENDERSON, Circuit Judge:

1

 When 

Charles Erwin, a commercial airline pilot with a diagnosed 

alcohol dependence, tested positive for alcohol, the Federal 

Aviation Administration (FAA) withdrew his medical 

certification required for flight. Erwin, whose test came less 

than a day after consuming food prepared in beer, requested 

reconsideration of the FAA’s decision with documentation to 

demonstrate that the positive test was due to unknowing 

exposure to alcohol. Standing firm, the FAA issued a short 

order denying Erwin’s request but failing to explain adequately 

its denial. Accordingly, we remand to the FAA for a more 

complete explanation of its decision. See Friedman v. FAA, 841 

F.3d 537, 544–45 (D.C. Cir. 2016) (Friedman I). 

I. Background 

A. Statutory and Regulatory Background 

The Congress has directed the FAA to “promote safe flight 

of civil aircraft” by promulgating regulations, including those 

“necessary for safety in air commerce.” 49 U.S.C. § 44701(a), 

(a)(5). Overseeing pilot certification is an important part of the 

FAA’s safety mandate. See id. § 44702. The FAA fulfills its 

safety mandate by requiring that, in addition to a pilot 

certificate, see id. § 44703(a), a commercial pilot hold a 

medical certificate issued under 14 C.F.R. part 67, 14 C.F.R. 

§ 61.3(c)(1). The requirements for medical-certificate 

eligibility vary based on the class of certificate sought. 14 

C.F.R. §§ 61.23(a), 67.101–.115 (first-class certificate), 

67.201–.215 (second-class certificate), 67.301–.315 (thirdclass certificate). A commercial airline pilot may exercise 

1

 NOTE: Portions of this opinion contain sealed information, 

which has been redacted. 
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certain privileges—for example, pilot-in-command 

privileges—only if he holds a first-class medical certificate. Id. 

§ 61.23(a)(1). For a first-class certificate, a pilot must meet a 

host of medical standards, including, inter alia, vision, 

physical, mental and cardiovascular standards. See id. 

§§ 67.101–.115. If a pilot meets all of the medical standards, 

he “is entitled to” an unrestricted medical certificate. Id. § 67.3. 

To meet the mental standards for an unrestricted medical 

certificate, a commercial airline pilot must not have an 

“established medical history or clinical diagnosis of . . . 

[s]ubstance dependence.” Id. § 67.107(a)(4). A codified 

exception to this prohibition allows a pilot with a diagnosed 

substance dependence to be eligible for an unrestricted medical 

certificate if “there is established clinical evidence, satisfactory 

to the Federal Air Surgeon, of recovery, including sustained 

total abstinence from the substance(s) for not less than the 

preceding 2 years.”2 Id. 

If a pilot with a diagnosed substance dependence fails to 

meet the “clinical evidence” test, the pilot must operate under 

a “Special Issuance of a Medical Certificate” (special issuance 

authorization). Id. § 67.401(a). The Federal Air Surgeon has 

discretion to grant a special issuance authorization and may do 

so if the pilot shows “to the satisfaction of the Federal Air 

Surgeon” that he can perform his duties “without endangering 

2

 The FAA Administrator has delegated the authority to 

“[i]ssue, renew, and deny medical certificates” and special issuance 

authorizations to the Federal Air Surgeon. 14 C.F.R. § 67.407(a). 

The Federal Air Surgeon heads the FAA’s Office of Aerospace 

Medicine, whose mission is to “[e]nhance aerospace safety through 

aeromedical standards, certification, surveillance, education and 

research.” Office of Aerospace Medicine Organization, FAA Order 

1100.3K , ch. 1, ¶ 7 (Nov. 1, 2018); see also id. at 11 (Figure 2-1). 
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public safety during the period in which the [a]uthorization 

would be in force.” Id. The Federal Air Surgeon may 

“[c]ondition the granting of a new [a]uthorization on the results 

of subsequent medical tests, examinations, or evaluations,” id. 

§ 67.401(d)(2), and may “[l]imit the duration of an 

[a]uthorization,” id § 67.401(d)(1). When the authorization 

expires, the pilot must “again show to the satisfaction of the 

Federal Air Surgeon” that he can perform his duties “without 

endangering public safety during the period in which the 

[a]uthorization would be in force.” Id. § 67.401(a). 

While a pilot holds a special issuance authorization, the 

Federal Air Surgeon retains discretion to withdraw it, see id. 

§ 67.401(f), and may exercise that discretion if, inter alia, 

“[t]here is [an] adverse change in the holder’s medical 

condition,” or “[t]he holder fails to comply with a statement of 

functional limitations or operational limitations issued as a 

condition of certification,” id. § 67.401(f)(1), (2). Within sixty 

days after service of the withdrawal letter, the pilot may request 

reconsideration by the Federal Air Surgeon and may file 

“supporting medical evidence” with the request. Id. 

§ 67.401(i)(2). The Federal Air Surgeon’s decision on the 

reconsideration request is a final agency order and issues 

within 60 days of the request. Id. § 67.401(i)(3). 

The airlines and the FAA have developed a cooperative 

program, the Human Intervention and Motivation Study 

(HIMS) program, to “coordinate[] the identification, treatment 

and return to” the cockpit of a pilot with a substance 

dependence.3

 Participation in the HIMS program is often a 

condition of a special issuance authorization. A HIMS Aviation 

3

 About HIMS, Human Intervention Motivational Study, 

https://himsprogram.com/about-hims/. 
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Medical Examiner (HIMS AME) is trained to oversee pilots 

who operate under special issuance authorizations and follows 

strict FAA reporting requirements. See FAA, Guide for 

Aviation Medical Examiners 421–29 (2021) (AME Guide). In 

September 2020, the FAA accepted NTSB Safety 

Recommendation A-07-43 and created the HIMS Step Down 

Plan (Plan).4 Memorandum from Penny M. Giovanetti, D.O. 

Director, Med. Specialties Div., AAM-200 to AAM-200, 

AMCD, Reg’l Flight Surgeons 1 (Sept. 8, 2020) (hereinafter 

HIMS Step Down Plan Memorandum). The Plan creates tiers 

through which a pilot progresses based on his recovery, 

effective on the date the FAA issues the special issuance 

authorization. See AME Guide at 447. The FAA, not the pilot’s 

HIMS AME, retains the final authority on when a pilot 

progresses through the tiers. Id. at 448. As he progresses, the 

pilot is subject to less onerous monitoring requirements. Id.; 

infra at 10–11. For example, by moving from the “Advanced 

Phase-3” to the “Maintenance Phase-4,” the pilot no longer 

must attend a weekly peer addiction support group or undergo 

random alcohol or drug testing. AME Guide at 447. 

B. Factual and Procedural History 

Charles Erwin (Erwin) is a commercial airline pilot who 

began his flying career over a decade ago, operating under an 

unrestricted first-class medical certificate.

Upon 

completion of an inpatient treatment program, Erwin entered 

4

 Documents related to the HIMS Step Down Plan are located 

on the HIMS program website: 

https://himsprogram.com/documents/. 
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the HIMS program to obtain a special issuance authorization 

because his substance dependence diagnosis and insufficient 

clinical evidence of the required two-year abstinence 

disqualified him from operating under an unrestricted medical 

certificate. Based on

and 

the FAA granted Erwin 

his first special issuance authorization (Authorization) on May 

17, 2017. Unsealed Joint Appendix (J.A.) 68–71. The 

Authorization contained monitoring conditions, including 

random alcohol testing at least fourteen times per year, 

biannual evaluations by Erwin’s HIMS AME, annual 

psychiatric evaluations, aftercare counseling and reporting 

requirements. J.A. 70. Crucially, the Authorization was 

“contingent upon total abstinence from alcohol.” J.A. 69 

(emphasis omitted). It was scheduled to expire on May 31, 

2020. 

On December 13, 2017, Erwin ate a lunch of pulled pork 

at a Franklin, Tennessee restaurant. The menu did not note that 

the pork was prepared in beer. Erwin took some of the meal 

home and ate the leftovers that night. The next morning, Erwin 

submitted to a random alcohol test. 

On December 28, 2017, one day after learning of the 

positive test, Erwin voluntarily took additional tests, 

specifically tests for phosphatidyl ethanol (PEth) in his blood 

and EtG in his hair and nails. Those tests came back negative. 
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Once the FAA learned of the positive test, it withdrew 

Erwin’s Authorization on January 9, 2018. 

On March 9, 2018, pursuant to 14 C.F.R. § 67.401(i), 

Erwin requested the Federal Air Surgeon to review the 

withdrawal, maintaining that he had tested positive due only to 

inadvertently consuming food cooked in beer. With his 

reconsideration request, Erwin submitted numerous exhibits 

and a report from a forensic toxicologist, Dr. Thomas Kupiec, 

to support his claim. The exhibits included, inter alia, evidence 

that Erwin ordered pulled pork at the restaurant, J.A. 191–92; 

an email from the restaurant stating that Erwin’s dish was, “in 

fact, cooked with beer,” even though the menu did not mention 

the beer, J.A. 193–94; 

a 2012 Substance Abuse and Mental Health 

Services Administration (SAMHSA) Advisory on biomarkers, 

J.A. 202–09; a 2005 Memo from the Alabama State Board of 

Medical Examiners cautioning against using solely a positive 

urine EtG test to take disciplinary action against an employee, 

J.A. 220–21; and a study recommending use of PEth tests after 

a positive EtS or EtG test, J.A. 227–31. Kupiec’s report 

discussed the drawbacks of using EtS/EtG tests to differentiate 

inadvertent exposure to alcohol and intentional alcohol use, 

concluding “within a reasonable degree of scientific certainty[] 

that the result of Mr. Erwin’s urine analysis does not represent 

conclusive evidence of intentional alcohol consumption.” The 

FAA requested additional documentation, which Erwin 

provided. In addition to the original documentation, Erwin 
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provided 

The FAA did not take action on his reconsideration request 

within the sixty-day time frame, 14 C.F.R. § 67.401(i)(3); 

instead, it reviewed Erwin’s documentation. It forwarded 

Erwin’s records to 

. On January 31, 

2019, the FAA issued Erwin a new special issuance 

authorization (Second Authorization), accepting Sager’s 

recommendations. Erwin is currently operating under the 

Second Authorization, which expires on January 31, 2024. 

Although the FAA believed it had resolved Erwin’s 

request, Erwin petitioned for a writ of mandamus in the U.S. 

District Court for the Western District of Oklahoma to compel 

the FAA to decide his reconsideration request. See Erwin v. 

FAA, et al., Case No. CIV-20-661-D (W.D. Okla. Oct. 14, 

2020). That action was dismissed after the Federal Air Surgeon 

issued a decision (Final Order). J.A. 303–04. The two-page 

Final Order explained that the Federal Air Surgeon “ha[d] 

reviewed [Erwin’s] agency medical file and the additional 

documentation [he] ha[d] submitted in support of [his] request 

for review of the withdrawal of [the] Authorization” and 

concluded that “the additional information and documentation 

is not sufficient to reverse” the withdrawal and “affirm[ed] the 

withdrawal of [the] Authorization.” J.A. 303. The Federal Air 

Surgeon noted that the positive alcohol test was an “adverse 

change” in Erwin’s medical condition, demonstrated that 
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Erwin did not maintain “total[] abstinen[ce]” and necessitated 

“a new evaluation of [his] current medical condition” in the 

interest of “public safety.” Id. (citing 14 C.F.R. § 67.401(f)). 

Erwin timely petitioned for review, claiming the Final Order 

was arbitrary and capricious under § 706(2)(A) of the 

Administrative Procedure Act (APA). 5 U.S.C. § 706(2)(A). 

II. Analysis 

A. Standing 

“Because Article III limits the constitutional role of the 

federal judiciary to resolving cases and controversies, a 

showing of standing ‘is an essential and unchanging’ predicate 

to any exercise of our jurisdiction.” Fla. Audubon Soc’y v. 

Bentsen, 94 F.3d 658, 663 (1996) (en banc) (internal citation 

omitted) (quoting Lujan v. Defs. of Wildlife, 504 U.S. 555, 560 

(1992)). To demonstrate the “irreducible constitutional 

minimum of standing,” Lujan, 504 U.S. at 560, the petitioner 

must show “(1) a personal injury-in-fact that is (2) fairly 

traceable to the defendant’s conduct and (3) redressable by the 

relief requested,” Int'l Bhd. of Teamsters v. TSA, 429 F.3d 

1130, 1134 (D.C. Cir. 2005) (quoting Rainbow/PUSH Coal. v. 

FCC, 396 F.3d 1235, 1240 (D.C. Cir. 2005)). The petitioner's 

standing burden is “the same as that of a plaintiff moving for 

summary judgment in the district court: it must support each 

element of its claim to standing ‘by affidavit or other 

evidence.’” Sierra Club v. EPA, 292 F.3d 895, 899 (D.C. Cir. 

2002) (quoting Lujan, 504 U.S. at 561). The alleged injury-infact must be “concrete and particularized,” and “actual or 

imminent, not conjectural or hypothetical,” Lujan, 504 U.S. at 

560 (internal quotation marks omitted), and “it must be likely, 

as opposed to merely speculative, that the injury will be 
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redressed by a favorable decision,” id. at 561 (internal 

quotation marks and citations omitted). 

Erwin’s case is unusual because his original Authorization 

would have expired on May 31, 2020, and he is currently 

operating under a Second Authorization that, on its face, 

imposes the same monitoring requirements as the original, 

albeit with a longer duration. Compare J.A. 68 (establishing 

duration of Authorization as thirty-six months), with J.A. 276 

(establishing duration of Second Authorization as sixty 

months). Accordingly, the FAA argues that even if we vacate 

its Final Order, Erwin cannot demonstrate an injury because he 

will “continue to be subject to an [a]uthorization with 

monitoring requirements—regardless of the expiration date 

stated on his Authorization—unless and until he meets the 

medical standards for an unrestricted certificate in [14 C.F.R.] 

part 67.” Resp’t Br. 40–41 (emphasis in original). 

To support his standing, Erwin asserts several injuries: 

additional monitoring requirements based on the Second 

Authorization, the lost opportunity to obtain an unrestricted 

medical certificate, damage to his reputation and

Because the first asserted injury is sufficient to establish 

standing, we “need not address” the final three. See Sierra Club 

v. EPA, 755 F.3d 968, 976 n.2 (D.C. Cir. 2014). 

Erwin has a cognizable injury arising from his poorer 

position in the HIMS Step Down Plan, and the accompanying 

extended monitoring, which we can likely redress by 

remanding the Final Order. See Lujan, 504 U.S. at 560–61. 

Erwin alludes to the Plan by referencing its genesis: NTSB 

Safety Recommendation A-07-43. Although neither Erwin nor 

the FAA elaborates on the Plan, the FAA has apparently begun 
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applying the Plan through guidance to pilots with special 

issuance authorizations. See AME Guide at 446–48. Under the 

Plan, pilots progress through tiers based on the number of years 

they have flown under a given special issuance authorization. 

See HIMS Step Down Plan Memorandum at 1. As they 

progress, the pilots “step down” in tiers and receive less 

monitoring as a result. See AME Guide at 447. The tiers are 

based on an “uncomplicated progression of recovery,” which 

includes compliance with the special issuance authorization, 

the pilot’s individual evaluation by HIMS professionals and 

FAA review. Id.

As a pilot currently under special issuance authorization,

Erwin is subject to the Plan. His Authorization issued on May 

31, 2017, but the FAA withdrew the Authorization and 

required Erwin to obtain the Second Authorization, which he 

has operated under since January 31, 2019. Erwin therefore is 

about two years further behind in his progression through the 

Plan than he would be but for the Final Order. Translated into 

tiers, the two-year gap puts Erwin in “Early Phase-2” rather 

than “Advanced Phase-3” and he will now not progress to 

Advanced Phase-3 until 2024. See AME Guide at 447. In Early 

Phase-2, he must undergo monthly peer-pilot and chief-pilot 

assessments that he would not have faced under the 

Authorization. See id. (demonstrating progression through 

tiers); J.A. 278 (detailing that Erwin must provide reports from 

his chief pilot and a peer pilot). 

By remanding the Final Order for “further proceedings,”5

it is “likely, as opposed to merely speculative,” see Lujan, 504 

5

 Under 49 U.S.C. § 46110(c), this court may only “affirm, 

amend, modify, or set aside any part of the order” but we may also 

“order the . . . [FAA Administrator] to conduct further proceedings.” 
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U.S. at 561, that we can redress Erwin’s lack of progression 

because his FAA medical file would include the remand, thus 

suggesting an “uncomplicated progression of recovery,” AME 

Guide at 447.

6

 The FAA suggests that Erwin will “continue to 

be subject to an [a]uthorization with monitoring requirements.” 

Resp’t Br. 40. But even if the FAA is correct—and it may not 

be—its position ignores the effects of the Plan. Erwin “need 

not prove that granting the requested relief is certain to redress 

[his] injury, especially where some uncertainty is inevitable.” 

Competitive Enter. Inst. v. NHTSA, 901 F.2d 107, 117–18 

(D.C. Cir. 1990). Having provided evidence of his continued 

“uncomplicated progression of recovery,” see supra at 7–8, 

with only the positive test to the contrary, Erwin has provided 

sufficient evidence for us to conclude that remand for further 

proceedings would likely redress his stunted Plan progress. 

B. Merits 

Having determined that Erwin has standing, we turn to the 

merits. Our review of the FAA Final Order is deferential: “We 

may overturn nonfactual aspects of the FAA’s decision only if 

they are ‘arbitrary, capricious, an abuse of discretion, or 

otherwise not in accordance with law.’” Boca Airport, Inc. v. 

FAA, 389 F.3d 185, 189 (D.C. Cir. 2004) (quoting 5 U.S.C. 

§ 706(2)(A)). “The FAA's factual determinations are 

conclusive if they are supported by substantial evidence.” City 

of Santa Monica v. FAA, 631 F.3d 550, 554 (D.C. Cir. 2011) 

(citing 49 U.S.C. § 46110(c)). We may not “substitute [our] 

judgment for that of the agency.” Motor Vehicle Mfrs. Ass’n of 

6

 At oral argument, FAA counsel indicated that a pilot’s FAA 

medical file includes “the entirety of his history with the FAA.” Tr. 

Oral Arg. 22. Our remand would therefore be part of Erwin’s medical 

file. 
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the United States, Inc. v. State Farm Mutual Auto. Ins. Co., 463 

U.S. 29, 43 (1983). Our role is to determine whether the FAA 

has “examine[d] the relevant data and articulate[d] a 

satisfactory explanation for its action” that does not “fail[] to 

consider an important aspect of the problem,” “run[] counter to 

the evidence” or is “so implausible that it could not be ascribed 

to a difference in view or the product of agency expertise.” Id.

We may not, however, “supply a reasoned basis for the 

agency’s action that the agency itself has not given.” Id. 

(internal quotation marks and citation omitted). 

Erwin argues that we should set aside the Final Order as 

arbitrary and capricious because the FAA failed to explain 

adequately its action. Erwin points to the FAA’s failure to 

explain “how a single positive test overcame all other 

documentation that supported [his] contention that he had an 

accidental, extraneous ethanol exposure” and highlights that 

the FAA did not mention “what documentation was reviewed, 

weighed, or assigned credibility” or why it “ignored” 

Pet’r 

Br. 23–24 . In response, the FAA argues that 

“quite frankly, there [was] not much more the Federal Air 

Surgeon needed to say” beyond linking the positive test and the 

violation of the conditions of his discretionary authorization. 

Resp’t Br. 37–38. The FAA further maintains that it need not 

“author an essay for the disposition of each application” and 

that “[i]t suffices, in the usual case, that [the court] can discern 

the why and wherefore.” Resp’t Br. 38 (second alteration in 

original) (quoting BellSouth Corp. v. FCC, 162 F.3d 1215, 

1224 (D.C. Cir. 1999)). 
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Here, however, the FAA asks us to “discern the why and 

wherefore” for its decision based on one statement in the 

Federal Air Surgeon’s Final Order: 

I have reviewed your agency medical file and 

the additional documentation you have 

submitted in support of your request for review 

of the withdrawal of your Authorization. I have 

determined, however, that the additional 

information and documentation is not sufficient 

to reverse the [withdrawal], and I must affirm 

the withdrawal of your Authorization. 

J.A. 303. Granted, an exegesis may not be necessary but the 

FAA has not provided even one sentence demonstrating a 

“rational connection between the facts found and the choice 

made.” State Farm, 463 U.S. at 43 (quoting Burlington Truck 

Lines v. United States, 371 U.S. 156, 168 (1962)). It argues that 

it may rely solely on the positive test and Erwin’s history of 

alcohol dependence but ignores Erwin’s evidence scientifically 

attacking the positive test, notwithstanding the withdrawal 

regulations explicitly provide that a request for review “may be 

accompanied by supporting medical evidence.” 14 C.F.R. 

§ 67.401(i)(2). In our view, Erwin’s reconsideration request 

and accompanying evidence, set out supra at 7–8, merits the 

FAA’s explicit consideration. Its Final Order does not do so. 

And the FAA is a repeat offender. As we have previously told 

the agency, it “cannot simply declare its ‘expertise’; it must 

exercise that expertise and demonstrate sufficiently that it has 

done so else we have nothing to review much less defer to.” 
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Village of Bensenville v. FAA, 376 F.3d 1114, 1122 (D.C. Cir. 

2004) (internal footnote omitted).7

The FAA acted arbitrarily and capriciously by failing to 

weigh the evidence provided with Erwin’s reconsideration 

request. See Pub. Citizen, Inc. v. FAA, 988 F.2d 186, 197 (D.C. 

Cir. 1993) (“The requirement that agency action not be 

arbitrary or capricious includes a requirement that the agency 

adequately explain its result.”). Given the lack of explanation, 

“any analysis of the FAA’s denial would be imprudent.” See 

Friedman I, 841 F.3d at 545; see also Fla. Power & Light Co. 

v. Lorion, 470 U.S. 729, 743–44 (1985) (“If the record before 

the agency does not support the agency action [or] if the agency 

7

 The FAA’s handling of an earlier medical certification 

decision speaks volumes. See Friedman v. FAA, 841 F.3d 537, 544–

45 (D.C. Cir. 2016) (Friedman I). In Friedman I, we rebuked the 

FAA for failing to provide “any rationale” to require specific 

diabetes data from a pilot candidate for a first-class special issuance 

authorization. See id. at 544–45. There, the FAA first attempted—

unsuccessfully—to provide a rationale for requiring the data in its 

briefs to this court. Id. at 544. Here, during oral argument, the FAA 

again tried to provide a post hoc explanation for its denial by arguing 

that Erwin’s “own forensic toxicology report that he submitted for 

[the FAA] to consider says that [his positive test] could be indicative 

of previous heavy drinking one to three days before the test” while 

at the same time conceding that explanation was absent from the 

Final Order. Tr. Oral Arg. 19–20. Granted, the FAA may on remand 

reach the same result after considering the non-record evidence cited 

in its brief, as it did successfully in Friedman II. See Friedman v. 

FAA, 890 F.3d 1092, 1097–98 (D.C. Cir. 2018) (Friedman II) (after 

remand, FAA adequately explained its data requirement by 

providing “its own, unequivocal medical explanation for requiring” 

specific data from diabetic pilot). Nonetheless, it will have then met 

its burden. 
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has not considered all relevant factors[,] . . . the proper course, 

except in rare circumstances, is to remand to the agency for 

additional investigation or explanation.”). Instead, we remand 

to the FAA for it to consider the evidence Erwin provided and 

to make explicit the “why and wherefore” of its action. 

BellSouth Corp., 162 F.3d at 1224. 

So ordered.