Document ID: chunk:federal_register_of_legislation:F2021C00482:body:0:p15
Version: federal_register_of_legislation:F2021C00482
Segment Type: other
Provision Reference: 
Character Range: 41599–44595

> 7,500
for vehicles in categories MB, MC, MD and NA ; and
(V12 - V22 ) > 2,700
for vehicles in categories ME, NB AND NC
where: V1 is the initial speed in km/h and V2 is the final speed in km/h at the end of the deceleration mode.

         35.5.9.1.1.2.1 The variables in the foregoing expression are not related to those specified in the formulae of clause 35.4.8.

35.5.9.1.1.3.       If the vehicle is not capable of attaining the initial speed required by clause 35.5.9.1.1.1 or clause 35.5.9.1.1.2, then the speed employed in each mode for the initial speed shall be not less than 80 per cent of the 'Maximum Laden Vehicle Speed' and the final speed shall not be greater than half the initial speed.
35.5.9.1.2.              During all deceleration modes the lowest numerical overall drive ratios as specified in clause 35.4.7 shall be continuously engaged. Deceleration modes shall be conducted from the initial speed to the final speed. During acceleration periods the drive train shall be employed to regain the initial speed in the shortest possible time. Notwithstanding the foregoing requirements, changes of vehicle direction essential to testing and negotiation of curved sections of track may be undertaken at constant vehicle speed. If the vehicle's performance characteristics are such as to preclude it from maintaining the specified maximum interval between successive brake applications, the time interval may be increased to the minimum time required by the vehicle to achieve the specified initial speed and to maintain it for 10 seconds before each successive deceleration mode.
35.5.9.1.3.              Vehicles shall attain a sustained deceleration of not less than 3 m/s2 during the first deceleration mode. Subsequent deceleration shall be conducted employing a 'Control' force not less than that established during the first deceleration mode without regard to the actual deceleration achieved.
35.5.9.1.4.              The Service Brake Fade Test shall be followed immediately by the Service Brake Fade Effectiveness Check.
35.5.9.2.                    Dynamometer Service Brake Fade Test
This test may be applied to brake systems using air at positive pressure and is based on the relevant conditions and procedures of Federal Motor Vehicle Safety Standard 121 - 36 F.R. 3817, February 27, 1971 "Air Brake Systems" issued by the National Highway Traffic Safety Administration of the United States Department of Transportation up to and including amendments shown in Federal Register Vol. 42 No. 126 of 30 June 1977.
35.5.9.2.1.              Testing shall be carried out in accordance with the conditions and requirements specified in Section 35.6
35.5.10.                      Service Brake Fade Effectiveness Check
35.5.10.1.                This procedure is not applicable to vehicles with brake assemblies which have been tested in accordance with the requirements of clause 35.5.9.2.
35.5.10.2.                The vehicle shall be accelerated over a distance not