Brake Tests

96 Car Nos 1 2 3 456 7 8 9 10 11 12 Equipment— PM PM UC UC PM PM UC UC PM PM UC UC 206. Fig. 58 shows separate indicator cards for the brake cylinder pressure on the locomotive and each car in the train, also the rate of reduction in brake pipe pressure on car six during the application. 207. The characteristic emergency action of the PM and the UC equipments is clearly shown. In the first half of the train the PM equip- ments appear to have a slight advantage in the time of starting the brake application, but by the time that any effective brake cylinder pressure is reached all the brakes are applying practically uniformly throughout the train. The more rapid application of the new equip- ment results in its maximum pressure being obtained before the maxi- mum (but lower) pressure is obtained on the PM equipment cars. This stop was somewhat rough but the shocks were not sufficient to be called severe nor objectionable enough to indicate that such a combi- nation would give rise to any trouble in general road operation. Emergency Stop AT 45 M.P.H. 208. High braking power on locomotive and mixed equipment on cars as follows:—_ Car Nos ... 1 2 3 45 6 7 8 9 10 11 12 Equipment PM PM PM PM PM PM PM PM PM UC UC UC 209. This arrangement of equipments was made to find out if there would be a different action on the train with the UC and PM equipments grouped together instead of mixed as for Fig. 58. 210. Fig. 59 shows the separate indicator cards for brake cylinder pressure on locomotive and each car, also the reduction in brake pipe pressure on car six. 211. During this test little shock was experienced, the stopping of the train being smoother than that of Fig. 58 just described. Several short, jerky movements were noticed soon after the brake application commenced and at the end of the stop there was a strong but gradual running out of slack. Emergency Stop at 30 M.P.H. 212. High braking power on locomotive and mixed equipment on cars as follows:— Car Nos 1 2 3 4 5 6 7 8 9 10 11 12 Equipment PM PM PM PM UC UC UC UC PM PM PM PM 213. Fig. 60 shows indicator cards similar to those of Fig. 58 and Fig. 59, but for a different arrangement of equipments as indicated above. W hile the slack action with this make-up of train was somewhat rougher than was experienced with all PM equipments, the shocks were not