---
kind: "section"
citation: "14 C.F.R. § 38.1"
title: "14"
number: "38.1"
heading: "Applicability."
url: "https://uscodex.org/cfr/14/38.1"
---

# §38.1. Applicability.

- (a) Except as provided in [paragraph (c)](#c) of this section, an airplane that is subject to the requirements of [40 CFR part 1030](/cfr/40/part1030.md) may not exceed the fuel efficiency limits of this part when original type certification under this title is sought. This part applies to the following airplanes:
  - (1) **A subsonic jet airplane that has—**
    - (i) **Either—**
      - (A) A type-certificated maximum passenger seating capacity of 20 seats or more;
      - (B) A maximum takeoff mass (MTOM) greater than 5,700 kg; and
      - (C) An application for original type certification that is submitted on or after January 11, 2021;
    - (ii) **Or—**
      - (A) A type-certificated maximum passenger seating capacity of 19 seats or fewer;
      - (B) A MTOM greater than 60,000 kg; and
      - (C) **An application for original type certification that is submitted on or after January 11, 2021.**
  - (2) **A subsonic jet airplane that has—**
    - (i) A type-certificated maximum passenger seating capacity of 19 seats or fewer;
    - (ii) A MTOM greater than 5,700 kg, but not greater than 60,000 kg; and
    - (iii) **An application for original type certification that is submitted on or after January 1, 2023.**
  - (3) **A propeller-driven airplane that has—**
    - (i) A MTOM greater than 8,618 kg; and
    - (ii) **An application for original type certification that is submitted on or after January 11, 2021.**
  - (4) **A subsonic jet airplane—**
    - (i) That is a modified version of an airplane whose type design was not certificated under this part;
    - (ii) That has a MTOM greater than 5,700 kg;
    - (iii) For which an application by the type certificate holder for a type design change is submitted on or after January 1, 2023; and
    - (iv) **For which the first certificate of airworthiness is issued with the modified type design.**
  - (5) **A propeller-driven airplane—**
    - (i) That is a modified version of an airplane whose type design was not certificated under this part;
    - (ii) That has a MTOM greater than 8,618 kg;
    - (iii) For which an application by the type certificate holder for a type design change is submitted on or after January 1, 2023; and
    - (iv) **For which the first certificate of airworthiness is issued with the modified type design.**
  - (6) **A subsonic jet airplane that has—**
    - (i) A MTOM greater than 5,700 kg; and
    - (ii) **Its first certificate of airworthiness issued on or after January 1, 2028.**
  - (7) **A propeller-driven airplane that has—**
    - (i) A MTOM greater than 8,618 kg; and
    - (ii) **Its first certificate of airworthiness issued on or after January 1, 2028.**
- (b) The requirements of this part apply to an airplane for which an application for a change in type design is submitted that includes a modification that meets the change criteria of [§ 38.19](/cfr/14/38.19.md). A modified airplane may not exceed the applicable fuel efficiency limit of this part when certification under this chapter is sought. A modified airplane is subject to the same fuel efficiency limit of [§ 38.17](/cfr/14/38.17.md) as the airplane was certificated to prior to modification.
- (c) **The requirements of this part do not apply to—**
  - (1) **Subsonic jet airplanes having a MTOM at or below 5,700 kg.**
  - (2) **Propeller-driven airplanes having a MTOM at or below 8,618 kg.**
  - (3) **Amphibious airplanes.**
  - (4) **Airplanes initially designed, or modified and used, for specialized operations.** These airplane designs may include characteristics or configurations necessary to conduct specialized operations that the FAA and the United States Environmental Protection Agency (EPA) have determined may cause a significant increase in the fuel efficiency metric value.
  - (5) **Airplanes designed with a reference geometric factor of zero.**
  - (6) **Airplanes designed for, or modified and used for, firefighting.**
  - (7) **Airplanes powered by reciprocating engines.**

## Notes

### Authority

Authority: 42 U.S.C. 4321 et seq., 7572; 49 U.S.C. 106(g), 40113, 44701-44702, 44704; 49 CFR 1.83(c)

### Source

Source: Docket No. FAA-2022-0241, Amdt. No. 21-107, 89 FR 12654, Feb. 16, 2024, unless otherwise noted.