---
kind: "section"
citation: "14 C.F.R. § 27.549"
title: "14"
number: "27.549"
heading: "Fuselage, landing gear, and rotor pylon structures."
url: "https://uscodex.org/cfr/14/27.549"
---

# §27.549. Fuselage, landing gear, and rotor pylon structures.

- (a) Each fuselage, landing gear, and rotor pylon structure must be designed as prescribed in this section. Resultant rotor forces may be represented as a single force applied at the rotor hub attachment point.
- (b) Each structure must be designed to withstand—
  - (1) The critical loads prescribed in [§§ 27.337 through 27.341](/cfr/14/27.337..27.341.md);
  - (2) The applicable ground loads prescribed in §§ [27.235](/cfr/14/27.235.md), [27.471 through 27.485](/cfr/14/27.471..27.485.md), [27.493](/cfr/14/27.493.md), [27.497](/cfr/14/27.497.md), [27.501](/cfr/14/27.501.md), [27.505](/cfr/14/27.505.md), and [27.521](/cfr/14/27.521.md); and
  - (3) The loads prescribed in § [27.547 (d)(2)](/cfr/14/27.547.md?p=d-2) and [(e)](/cfr/14/27.547.md?p=d-e).
- (c) Auxiliary rotor thrust, and the balancing air and inertia loads occurring under accelerated flight conditions, must be considered.
- (d) Each engine mount and adjacent fuselage structure must be designed to withstand the loads occurring under accelerated flight and landing conditions, including engine torque.

## Notes

### Amendments

[Doc. No. 5074, 29 FR 15695, Nov. 24, 1964, as amended by Amdt. 27-3, 33 FR 14105, Sept. 18, 1968]

### Authority

Authority: 49 U.S.C. 106(f), 106(g), 40113, 44701-44702, 44704.

### Source

Source: Docket No. 5074, 29 FR 15695, Nov. 24, 1964, unless otherwise noted.

### Amendments

[Doc. No. 5074, 29 FR 15695, Nov. 24, 1964, as amended by Amdt. 27-3, 33 FR 14105, Sept. 18, 1968]