ID: nht76-3.42

DATE: 03/23/76

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Titan Trailer Corporation

TITLE: FMVSS INTERPRETATION

TEXT: This responds to Titan Trailer Corporation's March 2, 1976, question whether certain bulk grain and feed meal trailers manufactured by Titan qualify as bulk agricultural commodity trailers that are permitted until June 30, 1976, to meet emergency and parking brake requirements other than those specified in S5.6 and S5.8 of Standard No. 121, Air Brake Systems.

Sections S5.6 and S5.8 provide that a trailer manufactured before June 30, 1976, that is designed to transport bulk agricultural commodities in off-road harvesting sites and to a processing plant or storage location, as evidenced by skeletal construction that accommodates harvest containers, a maximum length of 28 feet, and an arrangement of air control lines and reservoirs that minimizes damage in field operations, is entitled to a specified option.

From the descriptive material enclosed, it appears that the Titan models 92 and 24 are designed for field use and conform to the criteria of skeletal construction that accomodates a harvest container, despite the fact that the container is permanently attached to the frame that surrounds it. It is not clear that the trailers are not more than 28 feet in length, or that the design positions air lines and reservoirs to minimize field-related damage. Assuming that the length, air lines, and reservoirs do meet these criteria, it appears that the trailers would qualify for the manufacturer option under S5.6 and S5.8.

YOURS TRULY,

Titan Trailer corp.

March 2, 1976

Frank Burndt Acting Chief Counsel

On December 5, 1975, the NHTSA published an amendment to FMVSS 121 on page 235 of volume 40 of the Federal Register. This amendment exempted certain bulk agricultural commodity trailers from the parking brake requirements which had heretofore necessitated the use of spring brakes.

We manufacture a hopper trailer designed exclusively to haul bulk agricultural products. These trailers are frequently drawn through fields at harvest time by farm tractors - the conditions upon which the spring brake exemption was granted.

Several of our competitors, manufacturing similar hopper trailers, have told potential customers that these trailers are included under the spring brake exemption.

We would like to receive an official communication from your office as to whether or not these hopper trailers are covered under the spring brake exemption granted to agricultural commodities. To assist you in making this decision, we have enclosed photographs and a sales brochure pertaining to our hopper trailers.

Since our material orders and our sales will be strongly influenced by your response, we would greatly appreciate a prompt reply to this letter. Please feel free to contact me at (916) 662-3941 should you have any questions.

Thomas M. Tucker Assistant Manager

ID: nht76-3.43

DATE: 02/18/76

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

TO: Oshkosh Truck Corporation

TITLE: FMVSS INTERPRETATION

TEXT: This responds to Oshkosh Truck Company's January 22, 1976, question whether a vehicle that complies with S5.1.1 of Standard No. 121, Air Brake System, when it is moving must also comply with the requirement when it is stationary. Section S5.1.1 specifies an air compressor of sufficient capacity to increase air pressure in the supply and service reservoirs from 85 p.s.i. to 100 p.s.i. within a limited period when the engine is operating at the vehicle manufacturer's maximum recommended rpm.

Section S5.1.1 does not specify whether or not the vehicle is moving as a test condition for the requirement. In view of the absence of this test condition, the NHTSA will resolve differences in this test condition in the manufacturer's favor if they affect the outcome of testing.

Yours truly,

ATTACH.

January 22, 1976

T. Herlihy -- National Highway Traffic Safety Administration

Dear Mr. Herlihy:

Based on discussions with Sid Williams it is my understanding that section 5.1.1 of FMVSS 121 does not require that compressor buildup time be tested when the vehicle is stationary. If the vehicle meets compressor buildup time when it is moving, but exceeds compressor buildup time when the vehicle is stationary, it is my understanding that the vehicle qualifies. Please confirm.

Sincerely,

Danny Lanzdorf -- Supervising Engineer

cc. J. Westphal; D. Thekkanath

ID: nht76-3.44

DATE: 01/22/76

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

TO: Wagner Electric Corporation

TITLE: FMVSS INTERPRETATION

TEXT: This responds to Wagner Electric Corporation's October 21, 1975, question whether a trailer would satisfy the requirements of S5.2.1.1 of Standard No. 121, Air Brake Systems, to provide a reservoir "that is unaffected by a loss of air pressure in the service brake system," if the reservoir provided is either of two service brake system reservoirs on the vehicle, equipped with a pressure protection valve directly adjacent to each reservoir. The drawings enclosed in your letter indicate that the "protected tank" that is normally provided, separate from the service brake system, would be eliminated and either of the service brake system reservoirs would be used to satisfy S5.2.1.1 in the event of a parking brake application.

Your interpretation of S5.2.1.1 is correct. That section calls for a reservoir of air as an energy source that is used to release the vehicle's parking brakes after an automatic or manual application. In requiring that this reservoir be "unaffected by a loss of air pressure in the service brake system," the NHTSA means that a single failure of the service brake system would not result in loss of this air supply. With the pressure protection valves located as described in your enclosures, it appears that the system would comply with Section S5.2.1.1.

This "single failure" requirement must be distinguished from the requirement of S5.6.3 that the energy source for application of the parking brake be "not affected by loss of air pressure or brake fluid pressure in the service brake system." The NHTSA has interpreted this requirement to require an uninterrupted energy source despite loss of all air pressure from the service brake system. We recognize that the language of the two passages is substantially identical, and should be changed for clarity.

In a recent proposal to revise the parking brake requirements of the standard (40 FR 56920, December 5, 1975), the NHTSA inadvertently failed to make this distinction clear in its newly-proposed definition of "parking brake system" and intends to publish a correction of the proposal in the near future.

Yours truly,

ATTACH.

WAGNER ELECTRIC CORPORATION

October 21, 1975

Chief Counsel -- National Highway Traffic Safety Administration

Re: 49 CFR 571.121

Dear Sir: The early or first generation systems for FMVSS 121 complying trailers have completed almost a year of evaluation. Serious consideration for more economical systems has naturally evolved in this period of time.

In comparing tractor air brake systems and trailer air brake systems it is apparent that a good level of safety is provided on two axle tractors which employ only service reservoirs, i.e., do not have an isolated reservoir for the parking brake system. This introduced the probability that a (Illegible Word) axle trailer could benefit from a similar system schematic.

Our review of FMVSS 121 indicates that the equipment requirements are minimal - in keeping with the NHTSA policy of issuing performance oriented requirements. The system to be discussed later in this document meets all of the equipment requirements and will satisfy the related performance criteria.

In addition, all of the benefits for commercial or non-regulated necessities are maintained.

For introductory purpose we have reproduced the section from FMVSS 121 that deals with trailer equipment requirements:

S5.2.1.1 A reservoir shall be provided that is unaffected by a loss of air pressure in the service brake system.

On single axle trailers utilizing one service reservoir, a separate reservoir or protected reservoir compartment for parking brake control is clearly required to meet S5.2.1.1.

Tandem axle trailers afford other opportunities for system considerations. The system shown on Figure 1 introduces a new set of operating parameters which will in fact eliminate the expense of adding a third (parking brake control) reservoir on tandem axle trailers. We interpret S5.2.1.1 to mean that a single loss of air pressure in the service brake system following pressurization of the reservoir system to 90 psi shall not prevent a single release of the parking brakes.

The system shown on Figure 1 provides a separate reservoir and anti-lock system for the service brakes on each axle. Failure of system A will not reduce the pressure in service reservoir B or vise versa. The presence of one service reservoir pressurized to 90 psi will permit a full release of the parking brakes when the supply line is pressurized to the maximum 45 to 48 psi. The supply line pressure will be limited to this value by the pressure protection valve [which has an integral check valve] in the supply line immediately adjacent to the failed service reservoir. The four parking chambers will then receive a pressure of approximately 66 psi as delivered by the amplifying relay valve which receives air from the intact service reservoir.

This evaluation is based on the venting of one trailer service reservoir to atmosphere after the system is charged to 90 psi. We consider this to be the most extreme service brake system failure which can occur on the trailer. Note that a pressure loss in both service reservoirs would require two service brake system failures. Functional requirements following multiple service system failures is not required in any other section of FMVSS 121 and is not required in S5.2.1.1. We, therefore, conclude that the system shown on Figure 1 meets the intended requirements of S5.2.1.1.

The proposed system provides an opportunity to reduce the cost of the brake system required on tandem axle trailers. A comparison of the proposed system, which is Figure 1, with the existing system as shown on Figure 2 will show that the modification entails the addition of two check valves, one tee and three short lines to the amplifying relay valve and permits the elimination of the large parking brake reservoir, reservoir drain cock, supply line to the reservoir, and the cost of installing the reservoir on the vehicle. All of the parts shown on the schematics are currently being supplied for production FMVSS 121 trailer systems. The cost reduction can not be accurately defined by Wagner, but we estimate that the saving could range from $ 20.00 to $ 30.00 per vehicle depending on variable labor costs, reservoir cost, and vehicle configuration.

We encourage any NHTSA comments or questions regarding the system shown on Figure 1 and the requirements of S5.2.1.1 of FMVSS 121. It has been customary for requests for interpretation to the Chief Counsel's office which seek system or product "endorsement" to be answered by stating that the requesting party should be able to make that determination themselves.

In the instant case, we have made the determination that the dual service - two reservoir brake system for tandem axle trailers (Figure 1) is functionally acceptable and in compliance, and are therefore reporting it as such.

The dual service - two reservoir brake system for tandem axle trailers will be entering production in the immediate future. We would appreciate an acknowledgement of receipt of this letter and are anxious to answer any questions or supply additional information.

If you have any concern for the performance of the dual service - two reservoir brake system for tandem axle trailers or its compliance with respect to FMVSS 121 an early response from you will avoid the possibility of economic loss to the depressed trailer industry if, for some reason, they would have to reconvert this more economical system to earlier configurations.

Very truly yours,

John W. Kourik -- Chief Engineer, Automotive Products

Attachment

(Graphics omitted)

FIGURE 1

DUAL SERVICE - TWO RESERVOIR BRAKE SYSTEM FOR TANDEM AXLE TRAILER

(Graphics omitted)

FIGURE 1

DUAL SERVICE - TWO RESERVOIR BRAKE SYSTEM FOR TANDEM AXLE TRAILER

(Graphics omitted) FIGURE 2

DUAL SERVICE - THREE RESERVOIR BRAKE SYSTEM FOR TANDEM AXLE TRAILER

ID: nht76-3.45

DATE: 03/12/76

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

TO: Rockwell International

TITLE: FMVSS INTERPRETATION

TEXT: This responds to Rockwell International's February 17, 1976, question whether the addition by a manufacturer of a computer power relay unit (CPR) to an antilock system already installed on a vehicle in satisfaction of Standard No. 121, Air Brake Systems, is prohibited by @ 108(a)(2) of the National Traffic and Motor Vehicle Safety Act (15 U.S.C. @ 1397(a)(2)). Section 108(a)(2) provides that, with one exception, no manufacturer, distributor, dealer, or repair business shall knowingly render inoperative, in whole or part, any device or element of design installed on or in a motor vehicle in compliance with an applicable Federal motor vehicle safety standard. As you describe the CPR function, it is added to a functioning antilock system to sense improper electrical signals and to prevent them from causing the antilock system to release the brakes when they should remain applied. The CPR acts by discontinuing power to the antilock system and warning the driver.

Section 108(a)(2) has been construed by the NHTSA to apply to situations where a system installed in compliance with a safety standard is defeated so that it no longer possesses the performance capabilities considered necessary by the agency and set forth in its standards. The agency has determined that some modifications can be made (e.g., substitution of a bumper that meets current requirements in place of a bumper that meets earlier requirements) as long as the performance required by the standard is met. In the case of your CPR, the issue is whether the addition of a device that shuts off the antilock function under some malfunction circumstances would be considered "knowingly [rendering] inoperative" an element of Standard No. 121.

As you describe the CPR function, it would not. As in other standards, Standard No. 121 contemplates failure of the regulated system and provides for the safest operation of the system under such circumstances. For example, the standard calls for low-air and antilock-failure warning signals (S5.1) and for uninterrupted operation of the air brake system in the event of electrical failure in the antilock system (S5.5). Antilock manufacturers have also provided logic circuits in their systems to sense certain malfunctions and take corrective action. The fact that the Rockwell CPR is additional protection against malfunction that is being added to systems already installed is not a significant distinction. From your description, the CPR does not defeat the designed performance called for by Standard No. 121, and its installation by a manufacturer would not constitute a violation of @ 108(a)(2).

YOURS TRULY,

February 17, 1976

National Highway Traffic Safety Administration

Attention: Office of Defects Investigation

Subject: Rockwell SKID-TROL(R) Request for Interpretation

Under the date of July 10, 1975, Rockwell International wrote to NHTSA advising of a safety related anti-lock problem that existed on some units. Also included in that letter (copy attached) was a reference to a Rockwell developed in-vehicle diagnostic aid that would enhance the operation and safety of the wheel anti-lock device.

This unit is known as the Computer Power Relay (CPR Unit) and its function is to detect unwanted intermittent signals that may be encountered due to mechanical problems, such as loose wheel bearings or misadjusted wheel end parts.

A more detailed description of its function is as follows:

* The CPR unit has been designed to operate in conjunction with Rockwell's SKID-TROL(R) wheel anti-lock system and detects improper sensor-to-rotor gap as soon as it occurs without the brakes being applied. Further, it gives the operator warning of the condition and returns the vehicle to the manual braking mode. A return to manual braking occurs when the unit detects an abnormal solenoid switching that occurs before the brake pedal is depressed. If such a condition should occur, the CPR removes the power to all wheel anti-lock units on the vehicle until the unit is purposely reset and the condition causing the abnormal switching is corrected.

Since July 1975, the unit has been regularly installed with Rockwell SKID-TROL(R) systems with successful results. We have, however, been asked by a customer as to conflict with Sec. 103 (2) (A) of the Safety Act, Public Law 93-492, which reads in part "No manufacturer, distributor, dealer, or motor vehicle repair business shall knowingly render inoperative, in whole or part, any device or element of design installed on or in a motor vehicle or item of motor vehicle equipment in compliance with an applicable Federal motor vehicle safety standard."

The effect of the CPR unit is the same as that of the normal fail-safe portion of an anti-lock device, except that it has the added advantages of detecting unwanted intermittent signals and is resetable.

In any event, Rockwell International would appreciate NHTSA's interpretation that the unit does not conflict with Sec. 103, paragraph (2) (A) of the Safety Act.

ROCKWELL INTERNATIONAL CORPORATION AUTOMOTIVE OPERATIONS

G. J. Flannery Director - Government Relations

ATTACH.

July 10, 1975

National Highway Traffic Safety Administration

Attention: Office of Defects Investigation

Attached is a copy of our letter to vehicle manufacturers in connection with a safety related wheel anti-lock problem that exists on some units in use and could exist in the future as the result of misassembly in maintenance. Also attached is a listing of vehicle manufacturers to whom this notice has been sent.

The wheel anti-lock system is performing as designed and the malfunction results from mechanical causes rather than electrical. It is expected that the individual vehicle manufacturers receiving this notice will advise NHTSA of the actual number of units released to the field. Rockwell International estimates that the major number of suspect units were assembled during the first few weeks of production of FMVSS #121 type units. A cutoff date of July 1, 1975 has been established to insure that all suspect units are corrected. Rockwell International will advise NHTSA of the total units shipped to vehicle manufacturers as soon as it is available.

Included in the attached notification is a recommendation that wheel bearings should be properly adjusted and wheel ends checked with a Service Aid Tester after maintenance.

Rockwell International has also developed in-vehicle diagnostic equipment that will be available in the near future that detects mechanical problems affecting the wheel anti-lock system.

Rockwell International will, in the interest of highway safety, provide this diagnostic equipment without charge to operators for use in conjunction with Rockwell International wheel anti-lock systems unitl they can be incorporated into new production vehicles.

Rockwell International will continue to make an all out effort to assist vehicle manufacturers in remedying the problem contained in the attached notification.

ROCKWELL INTERNATIONAL CORPORATION AUTOMOTIVE OPERATIONS

G. J. Flannery Director - Government Relations

ID: nht76-3.46

DATE: 01/08/76

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

TO: B. F. Goodrich Engineered Systems Company

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your August 28, 1975, question whether use of compressed air from a trailer air brake system to supply non-brake equipment such as an air suspension would violate the requirements of Standard No. 121, Air Brake Systems.

The answer to your question is no. Standard No. 121 does not contain a prohibition on the use of air pressure from the air brake system for powering auxiliary devices. The vehicle must of course conform to Standard No. 121 following installation of the device, if the installation occurs prior to the first purchase in good faith for purposes other than resale. For example, the brake actuation timing would still be required to meet S5.3.3 of the standard.

Although not a requirement of the standard, the NHTSA does consider it appropriate that a pressure protective valve be placed in the line to the auxiliary device so that a rupture of an auxiliary line does not cause depletion of air pressure in the brake system.

With respect to your request for approval of four installations of auxiliary equipment, the NHTSA does not issue approvals of specific designs, and therefore cannot state that vehicles modified in the described fashion would or would not be capable of meeting all requirements of the standard.

YOURS TRULY,

B. F. Goodrich Engineered Systems Company

August 28, 1975

R. L. Carter Acting Administrator National Highway Traffic Safety Administration U.S. Department of Transportation

The B.F. Goodrich Company has received numerous requests from our trailer customers asking for our approval to obtain air for auxiliary items, such as air suspension bags from the anti-skid air system.

Attached is one copy each of four drawings, Nos. 1998-42-43-44-45 which shows four different places in the anti-skid air system that air could be obtained for auxiliary items. Drawing -45 shows taking air from the Sealco Ratio Relay Valve. To assist you in evaluating this drawing, we are attaching a Sealco pamphlet describing the operation of the Ratio Relay Valve. We would appreciate your review and interpretation as to whether any or all of these methods would violate the requirements of MVSS-121. We would appreciate an early review of these proposed methods of obtaining air for auxiliary systems so that we will be in a position to properly advise our customers.

If you have any questions concerning information on the attached drawings please do not hesitate to contact me. I will look forward to a response from you and thank you for your consideration.

D. L. Haines Divisional Manager, Quality Assurance

B.F. Goodrich Engineered Systems Company

December 1, 1975

R. L. Carter Acting Administrator National Highway Traffic Safety Administration U.S. Department of Transportation

Subject: Anti-Skid - Containment of Air for Auxiliary Items

Ref: My letter of August 28, 1975

Dear Mr. Carter:

Attached to referenced letter I sent one copy each of four drawings, Nos. 1998-42,43,44,45, showing four different areas in the anti-skid air system that air could be obtained for auxiliary items, such as air suspension bags.

As of this date, we have not received a response on your review and interpretation as to whether any or all of these proposed methods would violate the requirements of MVSS-121.

As I pointed out, B.F. Goodrich has received numerous requests from our trailer customers asking for our approval to obtain air for auxiliary items. Therefore, your prompt response to my August 28 letter will be greatly appreciated.

If you have any questions concerning this matter, please do not hesitate to contact me.

D. L. Haines Divisional Manager, Quality Assurance

ID: nht76-3.47

DATE: 03/30/76

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Great Dane Trailers, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This responds to Great Dane Trailers' February 23, 1976, letter asking if a trailer equipped with one or more axles that have a gross axle weight rating (GAWR) of 24,000 pounds or more is excluded from the requirements of Standard No. 121, Air Brake Systems.

Section S3. of Standard No. 121 provides in part that any vehicle manufactured before September 1, 1977, that has a GAWR for any axle of 24,000 pounds or more is excluded from the standard. The determination of GAWR is made by the vehicle manufacturer (49 CFR 571.3) and must be based on the capabilities of the axle system at 60 mph. Because the determination is made by the vehicle manufacturer, the NHTSA is unable to say that the components you mention in your letter would necessarily constitute an axle system with a GAWR of 24,000 pounds.

YOURS TRULY,

Great Dane Trailers, Inc.

February 23, 1976

James C. Schultz Chief Counsel National Highway Traffic Safety Administration D.O.T.

Re: FMVSS-121 49 CFR 571.121

In accordance with Part 571 Docket No. 74-10; Notice 16 issued May 12, 1975, Section S3. Application, it is stated that FMVSS-121 does not apply to any vehicle manufactured before September 1, 1976, that has a gross axle weight rating (GAWR) for any axle of 24,000 pounds or more.

If we produced a structurally sound semi-trailer with dual tires having a capacity of 6000 pounds each, mounted on an axle with 24,000 pound rating with two springs per axle having a rating of 12,000 pounds each (therefore a 24,000 pound GAWR), is this vehicle exempt from the FMVSS-12 regulations?

I will be looking forward to receiving your legal opinion on this matter.

Dudley E. DeWitt Manager/R & D

ID: nht76-3.48

DATE: 03/30/76

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Pullman Trailmobile

TITLE: FMVSS INTERPRETATION

TEXT: This responds to Trailmobile's March 4, 1976, letter asking if a trailer equipped with one or more axles that have a gross axle weight rating (GAWR) of 24,000 pounds or more is excluded from the requirements of Standard No. 121, Air Brake Systems.

Section S3. of Standard No. 121 provides in part that any vehicle manufactured before September 1, 1977, that has a GAWR for any axle of 24,000 pounds or more is excluded from the standard. The determination of GAWR is made by the vehicle manufacturer (49 CFR 571.3) and must be based on the capabilities of the axle system at 60 mph. Because the determination is made by the vehicle manufacturer, the NHTSA is unable to say that the components you mention in your letter would necessarily constitute an axle system with a GAWR of 24,000 pounds.

YOURS TRULY,

Pullman Trailmobile

March 4, 1976

Mr. Sidney F. Williams, Jr. National Highway Traffic Safety Administration Department of Transportation

Regarding our telephone conversation of March 3rd, would you confirm our discussion that a van trailer, having an axle rated at 24,000 pounds GAWR, based on adequate springs, axle beam, bearings, etc. and tires per Tire and Rim Association 60 MPH Rating would indeed be exempt from the Standard No. 121 "Air Brake Systems".

John R. Pratte Manager Materials Engineering

ID: nht76-3.49

DATE: 03/15/76

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Bock Products, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your February 11, 1976, question whether two trailer designs you describe would qualify as "Heavy Hauler Trailer[s]" as defined in Standard No. 121, Air Brake Systems. A copy of that definition is enclosed for your information.

Both of your trailer designs include a primary cargo-carrying surface that inclines from a height of 24 inches in the rear to a height of 47 inches in the front of the trailer. In one case, part of the inclined portion is removable, leaving a 6-foot length of the surface that is flat and 40 inches above the ground in the unloaded condition. In both cases somewhat more than one-half of the primary cargo-carrying surface is 40 inches or less in height.

The exclusion from Standard No. 121 for heavy hauler trailers applies (in relevant part) only to trailers "whose primary cargo-carrying surface is not more than 40 inches above the ground in an unloaded condition." The trailer designs you describe would not qualify for the exclusion, because only a portion of the surface qualifies as "not more than 40 inches above the ground."

SINCERELY,

BOCK PRODUCTS, INC.

Feb. 11, 1976

Office of the Chief Council NHTSA

Att: M.J. Herlihy

Mr. Sydney Williams of NHTSA suggested we write for a ruling on the enclosed designs to see if they would be exempt from the FMVSS #121.

They appear to fall within the description of the "Heavy Hauler Trailer", in that the bed height is below 40" over the primary cargo carrying length of the trailer.

However, to be sure of our position we are in need of a ruling by your office.

These designs would be used in the recreational vehicle industry as transporters for manufacturers of travel trailers and mini-motor homes.

Design #2 describes a 6'-0" section of removable ramp which would be left in position when transporting their product. It would install by pins at both ends.

We require your immediate attention on this matter as a rush order is pending.

Robert Fisher Sales Engineer/Coordinator

PROPOSED DESIGN PROFILE #2

DATE: 2-10-76

BOCK PRODUCTS 1901 W.HIVELY AVE. ELKHART, IND. 46514

NOTE! GROUND HEIGHT DIMENSIONS SHOWN ARE UNLOADED HEIGHTS

(Graphics omitted)

PROPOSED DESIGN PROFILE #1

DATE: 2-10-76

BOCK PRODUCTS

1901 W. HIVELY AVE. ELKHART, IND. 46514

NOTE! GROUND HEIGHT DIMENSIONS SHOWN ARE UNLOADED HEIGHT

(Graphics omitted)

ID: nht76-3.5

DATE: 04/13/76

FROM: STEPHEN P. WOOD FOR FRANK A. BERNDT -- NHTSA

COPYEE: BUREAU OF MOTOR CARRIER SAFETY

TITLE: FMVSS INTERPRETATION

TEXT: I am writing in response to your March 22, 1976, telephone conversation with Mark Schwimmer of this office concerning the treatment of plastic fuel tanks under Federal Motor Vehicle Safety Standard No. 301-75, Fuel System Integrity.

As Mr. Schwimmer explained, the National Highway Traffic Safety Administration has issued no safety standards that apply directly to fuel tanks. Standard No. 301-75, which applies to entire vehicles, specifies fuel spillage requirements for barrier crash and rollover tests, but does not include a flame envelopment test. In addition to passenger cars and school buses, the vehicles that are subject to the standard are multipurpose passenger vehicles, trucks, and buses with a Gross Vehicle Weight Rating of 10,000 pounds or less.

Standard No. 301-75 applies to new vehicles. In addition, the Federal Highway Administration's Bureau of Motor Carrier Safety has established requirements for certain vehicles in use in interstate commerce. I understand that a fuel tank flame envelopment test is among these. For information concerning such a test, you should communicate with that agency.

For your convenience, a copy of Standard No. 301-75 is enclosed.

ID: nht76-3.50

DATE: 03/11/76

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Lufkin Industries, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your February 6, 1976, questions whether Lufkin Industries may, as an incomplete vehicle manufacturer, build "incomplete chassis trailers" that do not have brakes installed that comply with Standard No. 121, Air Brake Systems, and whether Lufkin may tow the "incomplete chassis trailers" over the highway to the final-stage manufacturer without brakes that conform to Standard No. 121.

Lufkin's activities are regulated by Part 568 of Title 49 of the Code of Federal Regulations, if the "incomplete chassis trailers" qualify as "incomplete vehicles." A copy is enclosed for your information. Part 568 does not require the incomplete vehicle to meet all applicable safety standards, but @ 568.4 does require a statement of the status of an incomplete vehicle's conformity with all applicable standards.

In answer to your second question, the NHTSA permits the use of an incomplete vehicle on the public highways for the purpose of transit between the incomplete vehicle manufacturer and subsequent manufacturers, but for no other purpose, until such time as the vehicle complies with all Federal motor vehicle safety standards applicable to it as completed. This ruling by the NHTSA does not relieve the manufacturer or shipper from any applicable requirement imposed on the incomplete vehicle by other Federal, State, or local authority.

SINCERELY,

February 6, 1976

Administrator National Highway Traffic Safety Administration U. S. Department of Transportation

We would like to have your legal opinion on the following two questions:

1. We, as an original equipment manufacturer, have an order to build incomplete chassis trailers for another manufacturer who is qualified to complete and certify. He has requested we do not install the air brake system to meet S121 regulations. We would not certify these vehicles but would furnish the necessary documents prescribed for an incomplete vehicle.

Our question is: Can we legally build these incomplete vehicles with brakes that do not meet S121 regulation?

2. Provided we can legally build these vehicles, we would like to have your opinion on the following question:

Can the final stage manufacturer transport these incomplete vehicles over public highways pulling one vehicle with two like vehicles loaded on top? The supporting documents will accompany these vehicles.

Thank you for an early reply.

LUFKIN INDUSTRIES, INC. Trailer Division

A. G. Colburn Director of Trailer Design