---
kind: "section"
citation: "14 C.F.R. § 25.231"
title: "14"
number: "25.231"
heading: "Longitudinal stability and control."
url: "https://uscodex.org/cfr/14/25.231"
---

# §25.231. Longitudinal stability and control.

- (a) Landplanes may have no uncontrollable tendency to nose over in any reasonably expected operating condition or when rebound occurs during landing or takeoff. In addition—
  - (1) Wheel brakes must operate smoothly and may not cause any undue tendency to nose over; and
  - (2) If a tail-wheel landing gear is used, it must be possible, during the takeoff ground run on concrete, to maintain any attitude up to thrust line level, at 75 percent of VSR1.
- (b) For seaplanes and amphibians, the most adverse water conditions safe for takeoff, taxiing, and landing, must be established.

## Notes

### Amendments

[Doc. No. 5066, 29 FR 18291, Dec. 24, 1964, as amended by Amdt. 25-108, 67 FR 70828, Nov. 26, 2002]

### Authority

Authority: 49 U.S.C. 106(f), 106(g), 40113, 44701, 44702 and 44704; Pub. L. 115-254, 132 Stat 3281 (49 U.S.C. 44903 note).

### Source

Source: Docket No. 5066, 29 FR 18291, Dec. 24, 1964, unless otherwise noted.

### Amendments

[Doc. No. 5066, 29 FR 18291, Dec. 24, 1964, as amended by Amdt. 25-108, 67 FR 70828, Nov. 26, 2002]