---
kind: "section"
citation: "14 C.F.R. § 121.303"
title: "14"
number: "121.303"
heading: "Airplane instruments and equipment."
url: "https://uscodex.org/cfr/14/121.303"
---

# §121.303. Airplane instruments and equipment.

- (a) Unless otherwise specified, the instrument and equipment requirements of this subpart apply to all operations under this part.
- (b) Instruments and equipment required by §§ [121.305 through 121.359](/cfr/14/121.305..121.359.md) and [121.803](/cfr/14/121.803.md) must be approved and installed in accordance with the airworthiness requirements applicable to them.
- (c) Each airspeed indicator must be calibrated in knots, and each airspeed limitation and item of related information in the Airplane Flight Manual and pertinent placards must be expressed in knots.
- (d) Except as provided in §§ [121.627(b)](/cfr/14/121.627.md?p=b) and [121.628](/cfr/14/121.628.md), no person may take off any airplane unless the following instruments and equipment are in operable condition:
  - (1) Instruments and equipment required to comply with airworthiness requirements under which the airplane is type certificated and as required by §§ [121.213 through 121.283](/cfr/14/121.213..121.283.md) and [121.289](/cfr/14/121.289.md).
  - (2) Instruments and equipment specified in §§ [121.305 through 121.321](/cfr/14/121.305..121.321.md), [121.359](/cfr/14/121.359.md), [121.360](/cfr/14/121.360.md), and [121.803](/cfr/14/121.803.md) for all operations, and the instruments and equipment specified in [§§ 121.323 through 121.351](/cfr/14/121.323..121.351.md) for the kind of operation indicated, wherever these items are not already required by [paragraph (d)(1)](#d-1) of this section.

## Notes

### Amendments

[Docket 6258, 29 FR 19202, Dec. 31, 1964, as amended by Amdt. 121-44, 33 FR 14406, Sept. 25, 1968; Amdt. 121-65, 35 FR 12709, Aug. 11, 1970; Amdt. 121-114, 39 FR 44440, Dec. 24, 1974; Amdt. 121-126, 40 FR 55314, Nov. 28, 1975; Amdt. 121-222, 56 FR 12310, Mar. 22, 1991; Amdt. 121-253, 61 FR 2611, Jan. 26, 1996; Amdt. 121-281, 66 FR 19043, Apr. 12, 2001]

### Source

Source: Docket 6258, 29 FR 19205, Dec. 31, 1964, unless otherwise noted.

### Authority

Authority: 49 U.S.C. 106(f), 40103, 40113, 40119, 41706, 42301 preceding note added by Pub. L. 112-95, sec. 412, 126 Stat. 89, 44101, 44701-44702, 44705, 44709-44711, 44713, 44716-44717, 44722, 44729, 44732; 46105; Pub. L. 111-216, 124 Stat. 2348 (49 U.S.C. 44701 note); Pub. L. 112-95, 126 Stat. 62 (49 U.S.C. 44732 note); Pub. L. 115-254, 132 Stat. 3186 (49 U.S.C. 44701 note).

### Amendments

[Docket 6258, 29 FR 19202, Dec. 31, 1964, as amended by Amdt. 121-44, 33 FR 14406, Sept. 25, 1968; Amdt. 121-65, 35 FR 12709, Aug. 11, 1970; Amdt. 121-114, 39 FR 44440, Dec. 24, 1974; Amdt. 121-126, 40 FR 55314, Nov. 28, 1975; Amdt. 121-222, 56 FR 12310, Mar. 22, 1991; Amdt. 121-253, 61 FR 2611, Jan. 26, 1996; Amdt. 121-281, 66 FR 19043, Apr. 12, 2001]