Interpretation ID: nht74-2.10

DATE: 11/07/74

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: Columbia Body & Equipment Co.

TITLE: FMVSS INTERPRETATION

TEXT: This responds to CBE's October 24, 1974, question whether a trailer equipped with a telescoping drawbar that varies the distance between axles to conform to various State regulations would qualify as a "Heavy hauler trailer" as that term is defined in Standard No. 121, Air brake systems:

"Heavy hauler trailer" means a trailer with one or more of the following characteristics:

(1) Its brake lines are designed to adapt to separation or extension of the vehicle frame; or

(2) Its body consists only of a platform whose primary cargo-carrying surface is not more than 40 inches above the ground in an unloaded condition, except that it may include sides that are designed to be easily removable and a permanent "front-end structure" as that term is used in @ 393.106 of this title.

The answer to your question is no. The extension of the drawbar is not an "extension of the vehicle frame." This characteristic is intended only to describe trailers whose function necessitates a highly specialized configuration that significantly interferes with brake design. In contrast, the telescoping drawbar is not related to the trailer's function, but simply permits the vehicle to conform to State highway regulations.

Yours truly,

ATTACH.

October 24, 1974

Acting Chief Consel -- U.S. Dept. of Transportation

Attn: Richard Dyson

Dear Mr. Dyson;

Does the Pony Trailor on our drawing number T65-497 (enclosed) qualify as a heavy hauler trailer and exempt from the S121 or any other antiskid requirement until Sept. 1, 1976 as Mr. Tadd Herllhy defined in our phone conversation Oct. 23, 1974. Please reply as soon as possible.

Sincerely yours,

COLUMBIA BODY & EQUIPMENT COMPANY

John C. Hansen -- Sales Manager