---
kind: "section"
citation: "14 C.F.R. § 25.239"
title: "14"
number: "25.239"
heading: "Spray characteristics, control, and stability on water."
url: "https://uscodex.org/cfr/14/25.239"
---

# §25.239. Spray characteristics, control, and stability on water.

- (a) For seaplanes and amphibians, during takeoff, taxiing, and landing, and in the conditions set forth in [paragraph (b)](#b) of this section, there may be no—
  - (1) Spray characteristics that would impair the pilot's view, cause damage, or result in the taking in of an undue quantity of water;
  - (2) Dangerously uncontrollable porpoising, bounding, or swinging tendency; or
  - (3) Immersion of auxiliary floats or sponsons, wing tips, propeller blades, or other parts not designed to withstand the resulting water loads.
- (b) Compliance with the requirements of [paragraph (a)](#a) of this section must be shown—
  - (1) In water conditions, from smooth to the most adverse condition established in accordance with [§ 25.231](/cfr/14/25.231.md);
  - (2) In wind and cross-wind velocities, water currents, and associated waves and swells that may reasonably be expected in operation on water;
  - (3) At speeds that may reasonably be expected in operation on water;
  - (4) With sudden failure of the critical engine at any time while on water; and
  - (5) At each weight and center of gravity position, relevant to each operating condition, within the range of loading conditions for which certification is requested.
- (c) In the water conditions of [paragraph (b)](#b) of this section, and in the corresponding wind conditions, the seaplane or amphibian must be able to drift for five minutes with engines inoperative, aided, if necessary, by a sea anchor.

## Notes

### 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.