---
kind: "section"
citation: "49 C.F.R. § 238.409"
title: "49"
number: "238.409"
heading: "Forward end structures of power car cabs."
url: "https://uscodex.org/cfr/49/238.409"
---

# §238.409. Forward end structures of power car cabs.


This section contains requirements for the forward end structure of the cab of a power car. (A conceptual implementation of this end structure is provided in Figure 1 to this subpart.)

- (a) **Center collision post.** The forward end structure shall have a full-height center collision post, or its structural equivalent, capable of withstanding the following:
  - (1) A shear load of 500,000 pounds at its joint with the underframe without exceeding the ultimate strength of the joint;
  - (2) A shear load of 150,000 pounds at its joint with the roof without exceeding the ultimate strength of the joint; and
  - (3) A horizontal, longitudinal force of 300,000 pounds, applied at a point on level with the bottom of the windshield, without exceeding its ultimate strength.
- (b) **Side collision posts.** The forward end structure shall have two side collision posts, or their structural equivalent, located at approximately the one-third points laterally, each capable of withstanding the following:
  - (1) A shear load of 500,000 pounds at its joint with the underframe without exceeding the ultimate strength of the joint; and
  - (2) A horizontal, longitudinal force of 300,000 pounds, applied at a point on level with the bottom of the windshield, without exceeding its ultimate strength.
- (c) **Corner posts.** The forward end structure shall have two full-height corner posts, or their structural equivalent, each capable of withstanding the following:
  - (1) A horizontal, longitudinal or lateral shear load of 300,000 pounds at its joint with the underframe, without exceeding the ultimate strength of the joint;
  - (2) A horizontal, lateral force of 100,000 pounds applied at a point 30 inches up from the underframe attachment, without exceeding the yield or the critical buckling stress; and
  - (3) A horizontal, longitudinal or lateral shear load of 80,000 pounds at its joint with the roof, without exceeding the ultimate strength of the joint.
- (d) **Skin.** The skin covering the forward-facing end of each power car shall be:
  - (1) **Equivalent to a 1/2-inch steel plate with a 25,000 pounds-per-square-inch yield strength—** material of a higher yield strength may be used to decrease the required thickness of the material provided at least an equivalent level of strength is maintained;
  - (2) Securely attached to the end structure; and
  - (3) **Sealed to prevent the entry of fluids into the occupied cab area of the equipment.** As used in [paragraph (d)](#d), the term “skin” does not include forward-facing windows and doors.

## Notes

### Authority

Authority: 49 U.S.C. 20103, 20107, 20133, 20141, 20302-20303, 20306, 20701-20702, 21301-21302, 21304; 28 U.S.C. 2461 note; and 49 CFR 1.89.

### Source

Source: 64 FR 25660, May 12, 1999, unless otherwise noted.