---
kind: "section"
citation: "14 C.F.R. § 34.9"
title: "14"
number: "34.9"
heading: "Exceptions."
url: "https://uscodex.org/cfr/14/34.9"
---

# §34.9. Exceptions.

- (a) **Spare engines.** Certain engines that meet the following description are excepted:
  - (1) **This exception allows production of an engine for installation on an in-service aircraft.** A spare engine may not be installed on a new aircraft.
  - (2) Each spare engine must be identical to a sub-model previously certificated to meet all applicable requirements.
  - (3) A spare engine may be used only when the emissions of the spare do not exceed the certification requirements of the original engine, for all regulated pollutants.
  - (4) **No separate approval is required to produce spare engines.**
  - (5) The record for each engine excepted under this paragraph (c) must indicate that the engine was produced as an excepted spare engine.
  - (6) Engines produced under this exception must be labeled “EXCEPTED SPARE” in accordance with [§ 45.13](/cfr/14/45.13.md) of this chapter.
- (b) On and after July 18, 2012, and before August 31, 2013, a manufacturer may produce up to six Tier 4 compliant engines that meet the NOX standards of paragraph (d)(1)(vi) of this section rather than [§ 34.23(a)(2)](/cfr/14/34.23.md?p=a-2). No separate approval is required to produce these engines. Engines produced under this exception are to be labeled “COMPLY” in accordance with [§ 45.13](/cfr/14/45.13.md) of this chapter.

## Notes

### Amendments

[Doc. No. FAA-2012-1333, 77 FR 76850, Dec. 31, 2012]

### Authority

Authority: 42 U.S.C. 4321 et seq., 7572; 49 U.S.C. 106(g), 40113, 44701-44702, 44704, 44714.

### Source

Source: Docket No. 25613, 55 FR 32861, Aug. 10, 1990, unless otherwise noted.

### Amendments

[Doc. No. FAA-2012-1333, 77 FR 76850, Dec. 31, 2012]