Opinion for the Court filed by Circuit Judge HENDERSON.
Michael C. Gorman petitions for review of an opinion and order of the National Transportation Safety Board (NTSB or Board), which affirmed a Federal Aviation Administration (FAA) emergency order revoking Gorman’s commercial pilot certificate. The FAA found that Gorman deliberately violated Federal Aviation Regulations (FARs) by operating aircraft *582 carrying cargo for compensation or hire without obtaining the required operating certificate and operations specifications and without complying with competency and line check requirements set out in Subpart C of FAR Part 119, 14 C.F.R. §§ 119.31 et seq., and FAR Part 135, id. §§ 135.1 et seq., even after the FAA informed him he was required to do so under FAR section 119.23(b), 14 C.F.R. § 119.23(b). Gorman maintains, as he did below, that the regulation, which on its face applies only to aircraft “having a passenger-seat configuration of less than 20 seats,” id., does not apply to his two aircraft because they have no passenger seats and therefore no “passenger-seat configuration” whatsoever. Gorman also asserts that FAR section 119.23, as interpreted by the FAA, is ultra vires and that license revocation was too severe a sanction. For the reasons set out below, we conclude that the FAA reasonably construed its regulation to apply to aircraft with no passenger seats, that the regulation is not ultra vires and that Gorman has waived his objection to the severity of the penalty. Accordingly, we deny the petition for review.
I.
In 2003, Gorman obtained a Part 135 operating certificate to operate his business flying cargo in the form of bank checks for a single bank. In 2005, Gorman decided he did not need a Part 135 certificate to operate his business under the applicable FARs and obtained a written opinion from Robert Griscom, an “aviation attorney,” that as a “private carrier” Gor-man did not need such a certificate which, Griscom averred, is required only for “common carriers.” 1 See Hearing Ex. C-1, Sturgell v. Gorman, Docket No. SE-18094, at 2-3 (NTSB Sept. 25, 2007) (July 18, 2005 Letter from Robert Griscom to Mike Gorman). Gorman’s “private” carriage, Griscom opined, “may be conducted under the Rules of FAR Part 91,” id. at 3, which is titled “Air Traffic and General Operating Rules.” Griscom sent a copy of his opinion letter to Monroe P. Balton, FAA Regional Counsel for the Western Pacific Region, who responded that the opinion “accurately reflects the current state of the [FAA’s] regulations, Advisory Circular 120-12A and policy on the issue of private carriage.” Hearing Ex. C-2, Sturgell v. Gorman, at 1 (NTSB Sept. 25, 2007) (Aug. 19, 2005 Letter from Monroe P. Balton to Robert Griscom).
In March 2007, while on routine surveillance at the Long Beach, CA airport, two FAA aviation safety inspectors observed an airplane displaying “Charter advertising” on the side of the fuselage. When questioned by one of the inspectors, Gor-man, the airplane’s pilot, responded that he did not need an “Air Carrier Certificate” to operate his business. In a subsequent telephone conversation, the other inspector told Gorman that “he might be in violation of Pt. 119.23(b) if he was transporting bank checks for hire without an Air Carrier Certificate.” Hearing Ex. C-4, Sturgell v. Gorman, at 1 (NTSB Sept. 25, 2007) (Record of Apr. 10, 2007 telephone call from Mike Gorman to Gary Lackey). Gorman insisted that FAR section 119.23(b) did not apply to him because he was in “private carriage” and that he had legal opinions from Griscom and from FAA counsel Balton supporting his position. When contacted by the inspectors, Balton opined that “indeed Mr. Gorman *583 would need an Air Carrier Certifícate if he was transporting for hire in private carriage.” Id.
In April 2007, according to Gorman, FAA inspector Gary Lackey informed him by telephone that he was “grounded,” that he had “received bad advice from [his] attorney” and that he was “operating illegally.” Admin. Hearing Transcript, Sturgell v. Gorman, at 66 (Sept. 25, 2007 NTSB) (testimony of Gorman) (Hearing Tr.). After being advised by Griscom and other private counsel that Lackey lacked authority to ground him, Gorman called FAA Operations Unit Supervisor Robert W. Kemp. Kemp clarified that Gorman was not “grounded” but Kemp advised Gorman that “operations defined as ‘private carriage’ require the issuance of an operator’s certificate” and that Gorman’s operation “appears to meet this definition” and warned him that if Gorman was “engaged in this type of activity, [he] m[ight] be in violation of Title 14 of the Code of Federal Aviation Regulations (Title 14 CFR) and subject to civil penalties.” Hearing Ex. C-5, Sturgell v. Gorman (NTSB Sept. 25, 2007) (April 20, 2007 Letter from Robert W. Kemp to Mike Gorman).
On May 21, 2007, Balton drafted a memorandum addressing certification requirements for private carriage by a small airplane operator. Hearing Ex. C-6, Sturgell v. Gorman, (NTSB Sept. 25, 2007) (May 21, 2007 Memorandum from M. Balton to Long Beach Flight Standards District Offices) (Balton Memo). In it Balton stated that Advisory Circular 120-12A, which he had cited in his earlier opinion, had not been revised since 1986 and therefore did not take into account FAR Part 119, which “was issued and became effective later in time” and therefore “better represents the FAA’s position with respect to private carriage.” Id. at 1. Balton then set out the text of FAR section 119.23(b):
Each person who conducts noncommon carriage (except as provided in § 91.501(b) of this chapter) or private carriage operations for compensation or hire with airplanes having a passenger-seat configuration of less than 20 seats, excluding each crewmember seat, and a payload capacity of less than 6,000 pounds shall—
(1) Comply with the certification and operations specifications requirements in subpart C of this part;
(2) Conduct those operations in accordance with the requirements of part 135 of this chapter, except for those requirements applicable only to commuter operations;
14 C.F.R. § 119.23(b), quoted in Balton Memo at 2 (emphasis added). FAR section 119.23(b), Balton noted, “is regulatory in nature and must be complied with,” while Advisory Circular 120-12A “is ... advisory only — a suggested means of complying with the regulations” and “is not regulatory and is not enforced by the FAA.” Balton Memo at 2. Under FAR section 119.23, he explained, “large aircraft operators engaged in private carriage must have at least a certificate and operations specifications issued under Part 125, and small aircraft operators must hold a certificate and operations specifications issued under Part 119 and conduct operations in accordance with FAR Part 135.” Id. He therefore advised that Griscom’s opinion, “to the extent it fails to recognize this fact, ... is in error” and his earlier “concurrence” in Griscom’s opinion was “completely in error,” admitting that he had “failed to review the requirements of FAR Part 119” and had “only reread the advisory circular.” Id. at 3.
On June 1, 2001, Lackey drafted a letter to Gorman, with a copy of Balton’s memo attached, in which Lackey indicated that “cargo operations of this nature are indeed *584 subject to Title 14 Code of Federal Regulations 119.23(b) and require an air carrier certifícate.” Hearing Ex. C-7, Sturgell v. Gorman, at 1 (NTSB Sept. 25, 2007) (June 1, 2007 Letter from Gary W. Lackey to Mike Gorman). Thus, Lackey advised, “[cjontinued operations by you without an air carrier certificate [are] contrary to 14 CFR Part 119 and Part 135 and would be subject to enforcement action.” Id. Gor-man responded in a letter dated June 6, 2007, expressing his disagreement with Balton’s revised opinion. Exhibit C-8, Sturgell v. Gorman, at 1 (NTSB Sept. 25, 2007) (June 6, 2007 Letter from Mike Gor-man to FAA). Following this exchange, Gorman continued to operate his private carriage business as before, without regard to FAR section 119.23(b)’s directives to “[cjomply with the certification and operations specifications requirements in subpart C of [Part 119]” — requiring a covered person to obtain an “operating certificate” and “operations specifications that prescribe the authorizations, limitations, and procedures under which each kind of operation must be conducted,” 14 C.F.R. § 119.33(b) — and to “[c]onduct [his] operations in accordance with the requirements of part 135.”
On August 27, 2007, the FAA served an emergency order revoking Gorman’s commercial pilot certificate because, notwithstanding he was “advised by the FAA that [his] cargo operations were in violation of the FAR’s,” “on at least 20 occasions” he “continued said operations” from San Diego to Long Beach as “pilot in command,” “in deliberate disregard of FAA notification ... that such operation was in violation of the FAR’s,” in particular, FAR section 119.23(b). Emergency Order of Revocation, Michael Charles Gorman, Case No.2007WP050040, at 1-2 (FAA Aug. 27, 2007). The emergency order stated that each of the two aircraft Gorman was operating had “a passenger-seat configuration of less than 20 seats” and a “payload capacity of less than 6,000 pounds” and his operation of the flights “constituted non-common carriage or private carriage operations, for compensation or hire,” thereby triggering the certification and operations specifications requirements of FAR section 119.23 as well as the competency and line check requirements of FAR Part 135. Id. at 2. The order set out a list of provisions in FAR Parts 119 and 135 that Gorman’s operations violated. 2 Id. at 2-3. Based on the foregoing, the order concluded:
As a result of your operation in deliberate disregard of the FAA’s notification to you that such operations are in violation of the FAR’s, the Administrator finds that you lack the qualification necessary to hold a commercial pilot certificate, or an airman pilot certificate of any kind. She therefore has determined that safety in air commerce or air transportation and the public interest require the revocation of any and all airman pilot certificates you hold. The Administrator further finds that an emergency requiring immediate action exists with respect to safety in air commerce or air transportation.
Id. at 4. Accordingly, the emergency order directed that any certificate Gorman held be immediately revoked and surrendered to FAA Regional Counsel and that for one year thereafter, no application for a new airman certificate be accepted from him nor an airman certificate issued to him. Id.
Gorman appealed and a hearing was conducted by an NTSB administrative law judge (ALJ) on September 25, 2007. At *585 the hearing, Gorman argued that “Part 119.23(b) absolutely does not apply to all cargo operations, noncommon carriage in aircraft of [his] class.” Hearing Tr. at 71. He reasoned that FAR section 119.23(b) “only applies to aircraft having a passenger seat configuration” and his aircraft “d[id] not have a passenger seat configuration” because it did not have any passenger seats. Id. The FAA disagreed, maintaining that FAR section 119.23 applied to Gorman’s aircraft because “[zjero is less than 20.” Id. at 14.
At the conclusion of the hearing, the ALJ issued an oral ruling affirming the emergency order with respect to all but one of the alleged regulatory violations as well as the revocation of Gorman’s pilot’s certificate. 3 Id. at 120-21, 124. The ALJ concluded that, contrary to Gorman’s contention, the FAA reasonably interpreted FAR section 119.23(b)(l)-(2), which applies to “airplanes having a passenger-seat configuration of less than 20 seats,” to apply to aircraft such as Gorman’s which have no passenger seats:
If you have zero seats, you do have less than 20, in my view.
I, therefore find on the reasonable interpretation of this regulation, ... that Respondent did, in fact, change the passenger seat configuration in his aircraft by removing all of the passenger seats to zero seats, and zero seats is less than 20.
Hearing Tr. at 117-18. Based on his interpretation of FAR section 119.23(b), the ALJ found that Gorman violated not only FAR section 119.23(b) but also FAR sections 119.5(g), 119.33(b)(2), 119.33(b)(3), 135.293(a), 135.293(b) and 135.299(a), the requirements of which were triggered by FAR section 19.23(b). The ALJ also found that revocation was the appropriate sanction because:
[G]iven the fact that [Gorman] was advised in June, whether or not he agreed with it, he was advised that his operations were in probable violation of the appropriate regulation, he intentionally continued to operate upon his own determination that the FAA was wrong and he was right....
This was deliberate choice by [Gor-man] to disregard the advice and caution issued to him on his belief that his interpretation was correct and nobody in the [FAA] that he had dealt with knew what they were talking about.... That is inappropriate. If pilots simply disregard some portion of the regulations, operational, medical, whatever, maintenance, and say whatever they require or your interpretation that I’ve got to use this tool or this condition does not prohibit safe performance or I don’t have to comply, that would be chaos.
Id. at 122-23.
Gorman appealed the ALJ’s decision to the NTSB, which issued an order on November 1, 2007, denying the appeal and affirming the ALJ’s decision upholding the FAA’s emergency order (except as to FAR section 119.23(b)(3)). Opinion and Order, Sturgell v. Gorman, Docket SE-18094 (NTSB Nov. 1, 2007). The Board concluded that (1) it is “bound by all validly adopted interpretations of laws and regulations that the Administrator carries out, unless [it] find[s] that an interpretation is arbitrary, capricious, or otherwise not in accordance with law,” id. at 6, and (2) that section 119.23(b) is “clear on its face” and the FAA’s interpretation of it was therefore “not arbitrary, capricious or contrary to law and precedent,” id. at 8.
*586 Gorman filed a petition for review with this court on December 31, 2007. On January 28, 2008, Gorman filed a petition for rehearing with the NTSB, which the Board denied in an order issued May 13, 2008 for the following reason:
Respondent filed a petition for review of his case in the United States Court of Appeals for the District of Columbia Circuit on December 31, 2007, and that court has so notified the Board; therefore, the Board no longer has jurisdiction and the petition is subject to dismissal.
Sturgell v. Gorman, Docket SE-18094 at 1-2 (NTSB May 13, 2008) (NTSB Rehearing Order) (footnotes omitted) (citing 49 U.S.C. § 1153(b)(3)). Alternatively, the Board noted that, even if the filing of the petition for judicial review did not deprive it of jurisdiction, Gorman’s petition for rehearing “would have been untimely, and therefore subject to dismissal.” Id. at 2 n. 3.
On July 11, 2008, we ordered ma sponte “that the parties address in their briefs whether petitioner’s filing of a petition for agency rehearing after filing this petition for review renders the petition for review incurably premature.” Order, Gorman v. NTSB, No. 07-1532, at 1 (July 11, 2008).
II.
We first address the jurisdictional issue and then move on to the merits.
A. Jurisdiction
As recited
supra,
the NTSB issued its final decision on the merits on November 1, 2007 and Gorman filed a petition for review with the court on December 31, 2007. Gorman subsequently filed a rehearing petition with the NTSB on January 28, 2008—outside the prescribed 30-day window,
see
49 C.F.R. § 821.50(a)-(b) (petition “for rehearing, reargument, reconsideration or modification of a Board order on appeal from a law judge’s initial decision or order ... must be filed with the Board, and simultaneously served on the other parties, within 30 days after the date of service of the Board’s order on appeal from the law judge’s initial decision or order”)—and on May 13, 2008, the NTSB issued the order dismissing the rehearing petition. Pursuant to the court’s July 11, 2008 order, the parties have briefed the issue whether Gorman’s petition here is “incurably premature.” Order,
Gorman v. NTSB,
No. 07-1532, at 1 (citing
Collins v. NTSB,
Our caselaw “treat[s] a petition for review filed during the pendency of a request for administrative reconsideration as ‘incurably premature,’ and in effect a nullity.”
Collins,
In
United Transportation Union v. ICC,
“Where a motion for rehearing is in fact filed there is no final action until the action is denied * * *. [W]hen the party elects to seek a rehearing there is always a possibility that the order complained of will be modified in a way which renders judicial review unnecessary. Practical considerations!,] therefore, dictate that when a petition for rehearing is filed, review may properly be deferred until this has been acted upon.”
B. The Merits
Gorman offers three challenges to the NTSB’s affirmance of the FAA’s emergency order. We address each challenge seri-atim.
1. FAR section 119.23(b)
Gorman argues that the NTSB erred in two respects when it concluded that the language of FAR section 119.23(b) requires Gorman to obtain an operating certificate and operations specifications *588 and to comply with Part 135. We find neither argument persuasive.
First, Gorman contends the regulation’s language unambiguously excludes Gor-man’s two aircraft from its requirements for the reason he argued before the NTSB, namely, that, because all of the seats have been removed from each aircraft, neither can be described as “having a passenger-seat configuration of less than 20 seats.” Instead, he maintains that his airplanes now have no seating configuration whatsoever. We conclude that the regulation is ambiguous regarding its applicability to aircraft like Gorman’s and that the FAA reasonably determined that it does apply.
In common parlance, the phrase “airplanes having a passenger-seat configuration of less than 20 seats” may be reasonably understood to include aircraft having no passenger seats at all, as the FAA interpreted it. As the ALJ explained: “Zero is, in fact, a number” and “[i]f you have zero seats, you do have less than 20.” Hearing Tr. at 117. Any doubt that this is a permissible interpretation is dispelled by the language of the regulation’s heading which reads: “Operators engaged in passenger-carrying operations, cargo operations, or both with airplanes when common carriage is not involved,” 14 C.F.R. § 119.23 (emphasis added). This language plainly includes an aircraft that carries cargo only — and therefore has zero passenger seats — as well as one that carries passengers only or a combination of passengers and cargo, both of which, by contrast, would necessarily have at least one passenger seat. 5
Second, Gorman contends that even if the regulation is ambiguous, the NTSB erred in deferring to the FAA’s interpretation for two reasons: (1) “the NTSB itself acted arbitrarily and capriciously by failing to consider and address the arguments that Mr. Gorman raised against such deference” and (2) “the NTSB erred in failing to recognize that the FAA’s interpretation of its regulations was arbitrary, capricious, and otherwise not entitled to any deference.” Pet’r Br. at 28.
Both arguments misapprehend— and limit — the nature of our review. With regard to the meaning of the FAA’s regulation, our review does not, as Gorman suggests, involve “two distinct levels of deference” — ours to the NTSB and the NTSB’s to the FAA. The NTSB does indeed owe deference to the FAA’s interpretation of the regulation: “When conducting a hearing under [49 U.S.C. § 449(d) ], the Board ... is bound by all validly adopted interpretations of laws and regulations the Administrator carries out and of written agency policy guidance available to the
*589
public related to sanctions to be imposed under this section unless the Board finds an interpretation is arbitrary, capricious, or otherwise not according to law.” 49 U.S.C. § 44709(d). Nonetheless, while we review the NTSB’s decision to determine whether it is “ ‘arbitrary, capricious, an abuse of discretion, or otherwise not in accordance with law,’ ” when we construe the regulation, “like the NTSB, we must defer to the FAA’s interpretations of its own aviation regulations.”
Garvey v. NTSB,
Gorman also challenges the FAA’s interpretation on three grounds: (1) the regulation unambiguously excludes Gorman’s aircraft from its scope, Pet’r Br. at 32; (2) the FAA changed course without “reasoned analysis” when Balton revised his opinion,
id.
at 34 (citing
N. Mun. Distribs. Group v. FERC,
2. The FAA’s Statutory Authority
Next, Gorman asserts that if (contrary to his view) FAR section 119.23 requires that he obtain a Part 135 certificate, the regulation exceeds the FAA’s authority in two respects. We reject this argument as well.
First, Gorman contends that FAR section 119.23 is ultra vires because the FAA’s authority to issue operating certificates is statutorily limited by 49 U.S.C. § 44702 to issuing operating certificates to “air carriers” and “airports” — and Gorman is neither one. Section 44702(a) provides in relevant part: “The Administrator of the Federal Aviation Administration may *590 issue airman certificates, type certificates, production certificates, airworthiness certificates, air carrier operating certificates, airport operating certificates, air agency certificates, and air navigation facility certificates under this chapter.” 49 U.S.C. § 44702 (emphasis added). It is true that this provision does not specifically authorize the FAA to issue an operating certificate to Gorman as he operates neither as an “airport” nor as an “air carrier,” the latter being defined as “a citizen of the United States undertaking ... to provide ... foreign air transportation, interstate air transportation, or the transportation of mail by aircraft,” none of which is a part of Gorman’s operations. Id. § 40102(a)(2)(5). Nor, however, does it prohibit the FAA from issuing operating certificates in other circumstances under the authority of a different statute. 6 In this case, as the NTSB asserts, such certification authority is found in 49 U.S.C. § 44701.
Section 44701 provides in relevant part: The Administrator of the Federal Aviation Administration shall promote safe flight of civil aircraft in air commerce by prescribing—
(5) regulations and minimum standards for other practices, methods, and procedure the Administrator finds necessary for safety in air commerce and national security.
49 U.S.C. § 44701(a)(5). This statute grants the FAA “broad authority to regulate civil aviation.”
Ass’n of Flight Attendants—CWA v. Chao,
Second, Gorman argues the FAA lacked statutory authority to require Gorman to hold an operating certificate because the FAA has itself limited its certificating authority under Part 119 to operations in “air commerce.”
See
14 C.F.R. § 119.1(a)(1) (“This part applies to each person operating or intending to operate civil aircraft—(1) As an air carrier or commercial operator, or both, in air commerce;.... ”). In particular, Gor-man contends he does not operate aircraft as a “commercial operator” which
*591
involves “air commerce”—defined by regulation to include
“interstate, overseas, or foreign air commerce,”
14 C.F.R. § 1.1 (emphasis added)
8
—because Ms flights are “wholly intrastate, involving transportation of cargo between Long Beach, California and Montgomery Field in San Diego.” Pet’r Br. at 40. Gorman acknowledges, however, that “air commerce” includes not only “interstate, overseas, or foreign air commerce” but also
“any
operation or navigation of aircraft ... which may endanger safety in, interstate, overseas, or foreign air commerce,” 14 C.F.R. § 1.1 (emphasis added), and he does not deny that operations such as his could pose such a danger so as to require certification and the consequent regulatory compliance.
See Hill v. NTSB,
3. Appropriateness of Sanction
Finally, Gorman contends that the sanction the FAA imposed—revocation of his commercial pilot certificate—is excessive and arbitrary and capricious. Because Gorman failed to raise this objection before the NTSB, and offers no reasonable ground for this failure, we conclude that he has waived the objection. See 49 U.S.C. § 1153(b)(4) (“In reviewing an order under this subsection, the court may consider an objection to an order of the Board only if the objection was made in the proceeding conducted by the Board or if there was a reasonable ground for not making the objection in the proceeding.”).
For the foregoing reasons, the petition for review is denied.
So ordered.
Notes
. A. “common” carrier is a carrier "that holds itself out to the public, or to a particular class or segment, as willing to furnish transportation for hire.” 14 C.F.R. § 375.40(b). “Noncommon” or "private” carriage is "an aircraft operation for compensation or hire that does not involve a holding out to others.” 14 C.F.R. § 119.3; see, e.g., 14 C.F.R. § 119.5(h) (contrasting "common carriage” with "noncommon or private carriage”).
. These sections are 14 C.F.R. §§ 119.5(g), 119.23(b)(l)-(2), 119.33(b)(2)-(3), 135.295(a), 135.299(a)-(b). Hearing Tr. at 120-21.
. The ALJ found that Gorman did not violate FAR section 119.23(b)(3) as set forth in the emergency order.
. Our holding does not necessarily bar the agency from entertaining a late filed petition for rehearing or the court from remanding to the agency if it deems the agency likely to reconsider its decision.
See
49 C.F.R. § 821.11(b) (“Extensions of time to file petitions for reconsideration shall ... be granted ... only in extraordinary circumstances.”);
cf. Williston Basin Interstate Pipeline Co. v. FERC,
. Gorman asserts that “longstanding legal principles” prohibit considering the regulation's heading to elicit the meaning of its text. Reply Br. at 13-14 (citing
Bhd. of R.R. Trainmen
v.
Balt. & Ohio R.R.,
. The Congress has itself recognized that the list of certificates has proved incomplete and has therefore, as Gorman notes, inserted additional kinds of certificates over the years. See, e.g., Vision 100—Century of Aviation Reauthorization Act, Pub.L. No. 108-176, § 227, 117 Stat. 2490, 2531 (2003) (authorizing "design organization certificates").
. Gorman contends that section 44711(a)(5) should be read to mean that only regulations may be prescribed pursuant to section 44701 and that certificates must be issued pursuant to sections 44702-44716. See Pet'r Supp. Br. (filed Jan. 15, 2009). We find this cramped reading less natural and therefore less likely than the meaning we ascribe in the text.
. The definition reads in its entirety:
Air commerce means interstate, overseas, or foreign air commerce or the transportation of mail by aircraft or any operation or navigation of aircraft within the limits of any Federal airway or any operation or navigation of aircraft which directly affects, or which may endanger safety in, interstate, overseas, or foreign air commerce.
14 C.F.R. § 1.1.