Search Interpretations

08-007276as smidler

Mr. Francis S. Smidler

Director of Project Engineering

Wabash National Corp.

P.O. Box 6129

Lafayette, IN 47903

Dear Mr. Smidler:

This responds to your letter concerning a trailer you are developing for the transport of long items, such as windmill blades. You ask whether your telescoping trailer design would be considered by NHTSA to be a pole trailer, and thus excluded from the requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 224, Rear Impact Protection. Based on our understanding of the information you provided in your letter, our answer is yes.

By way of background, the National Highway Traffic Safety Administration (NHTSA) is authorized to issue FMVSSs that set performance requirements for new motor vehicles and items of motor vehicle equipment (see 49 U.S.C. Chapter 301). NHTSA does not provide approvals of motor vehicles or motor vehicle equipment.  Instead, manufacturers are required to self-certify that their products conform to all applicable safety standards that are in effect on the date of manufacture. NHTSA selects a sampling of new vehicles and equipment each year to determine their compliance with applicable FMVSSs.  If our testing or examination reveals an apparent noncompliance, we may require the manufacturer to remedy the noncompliance, and may initiate an enforcement proceeding if necessary to ensure that the manufacturer takes appropriate action.

The definition of a pole trailer, set forth in 49 CFR 571.3, reads as follows:

Pole trailer means a motor vehicle without motive power designed to be drawn by another motor vehicle and attached to the towing vehicle by means of a reach or pole, or being boomed or otherwise secured to the towing vehicle, for transporting long or irregularly shaped loads such as poles, pipes, or structural members capable generally of sustaining themselves as beams between the supporting connections.


In describing your vehicle, you state that:

The trailer has three main frame sections that telescope out from each other. From a closed length of 53 feet it can be extended to 128 feet or more. In addition, the bolster and rear frame can also be extended out further aft to accommodate payloads that may extend beyond the length of the main frame.

We note that the definition of pole trailer has two parts. The first is that the vehicle must be a vehicle without motive power, and must be attached to the towing vehicle by means of a reach or pole, or being boomed or otherwise secured to the towing vehicle. We assume for the purposes of this letter that your trailer is unpowered, and that it would be otherwise secured to the towing vehicle. Thus, it meets this first part of the definition.

The second part concerns the use for which the trailer was designed (for transporting long or irregularly shaped loads such as poles, pipes, or structural members capable generally of sustaining themselves as beams between the supporting connections). This means that the items pole trailers are designed to transport must be capable of being laid or secured across any gulf or gap between supporting connections. They have to be capable generally of sustaining themselves as beams. Windmill blades, like poles and pipes, are contiguous structural members that are capable of supporting themselves as beams. Thus, the second part of the definition appears to be met.

Given what you have described in your letter, we have determined that your trailer meets the definition of a pole trailer. However, we note that you did not provide a picture or description of the telescoping frame sections that attach the rear part of the trailer to the tractor. If further information led us to believe that the trailer was capable of, and in fact used for, carrying loads other than those for which a pole trailer is designed, that could provide cause to change our determination.

If you have any further questions, please contact Ari Scott of my staff at (202) 366-2992.

Sincerely yours,

Stephen P. Wood

Acting Chief Counsel

ref:224

d.2/26/09