---
kind: "section"
citation: "49 C.F.R. § 238.717"
title: "49"
number: "238.717"
heading: "Truck-to-carbody attachment."
url: "https://uscodex.org/cfr/49/238.717"
---

# §238.717. Truck-to-carbody attachment.


To demonstrate the integrity of truck-to-carbody attachments, each unit in a Tier III trainset shall:

- (a) Comply with the requirements in [§ 238.219](/cfr/49/238.219.md); or
- (b) Have a truck-to-carbody attachment with strength sufficient to resist, without yielding, the following individually applied, quasi-static loads on the mass of the truck at its CG:
  - (1) 3g vertically downward;
  - (2) 1g laterally, along with the resulting vertical reaction to this load; and
  - (3) Except as provided in [paragraph (c)](#c) of this section, 5g longitudinally, along with the resulting vertical reaction to this load, provided that for the conditions in the dynamic collision scenario described in [§ 238.705(a)](/cfr/49/238.705.md?p=a):
    - (i) The average longitudinal deceleration at the CG of the equipment during the impact does not exceed 5g; and
    - (ii) **The peak longitudinal deceleration of the truck during the impact does not exceed 10g.**
- (c) As an alternative to demonstrating compliance with [paragraph (b)(3)](#b-3) of this section, the truck shall be shown to remain attached after a dynamic impact under the conditions in the collision scenario described in [§ 238.705(a)](/cfr/49/238.705.md?p=a).
- (d) For purposes of [paragraph (b)](#b) of this section, the mass of the truck includes axles, wheels, bearings, truck-mounted brake system, suspension system components, and any other component attached to the truck by design.
- (e) Truck attachment shall be demonstrated using a validated model.

## Notes

### Source

Source: 83 FR 59219, Nov. 21, 2018, unless otherwise noted.

### 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.