para amortiguadores hidráulicos además de

los requisitos siguientes: a. Verificación de Pesos para Pruebas. El peso requerido para la prueba al choque será exacto hasta más o menos uno (1) por ciento. - 90 - b. Guiding of Test Weight. The test weight shall be so guided as to insure that when dropped onto the buffer its travel shall be substantially vertical. c. Test Instruments: The instruments used to measure the test results shall conform to the following requirements: 1. They shall be of the recording type. 2. They shall provide data for the plotting of the buffer performance curves showing time intervals, travel of test weight, velocity of test weight and retardation of test weight during the buffer stroke which shall be accurate to within the following tolerances: a. The timing device shall record time in increments of not more than one-sixtieth (1/60) second during the entire buffer stroke. b. Time increments and total time shall be recorded with an error of less than plus or minus five-tenths (5/10) of one (1) per cent. c. The position of the test weight at each USAS,A17.1 time interval shall be recorded with an Ibid error of less than plus or minus onetenth (1/10) of one (1) per cent. d. Time and travel, velocity and retardation shall be determined by means of a device which will provide the accuracy specified. Ibid