seated in the cab across from the engineer; the brakeman was seated in the cab of the third unit, SP 7549. According to the engineer, the brakeman was seated in the third unit to keep warm because the second unit, SP 7551, was not operating. The engineer stated that the dynamic brakes on SP 8278 were "working," and that when he asked the brakeman about the condition of the dynamic brakes on SP 7549, the brakeman replied, "It's revving." The engineer further stated that he did not conduct a visual observation of SP 7549 to determine if its dynamic brakes were operative. Extra 7551 East proceeded to Oban, and the dispatcher instructed the crew to move into the siding at that location to await a westbound train that was being assisted by a helper unit; the helper unit would be cut off and used to assist Extra 7551 East over the Cajon Pass.
Activities of Helper Unit.—At 1:30 a.m., on May 12, 1989, an SP crew, consisting of a locomotive engineer and brakeman, reported for duty at West Colton yard. The crew was transported in a company van from West Colton yard to Dike (MP 481) (see figure 1), arriving at that location at about 2:30 a.m. The crew took charge of a two-unit locomotive consist, SP 7443 (facing west) and SP 8317 (facing east), that was to be used in helper service (assisting trains traversing Cajon Pass). The crew (hereinafter referred to as the helper engineer and the helper brakeman) was instructed by the train dispatcher to operate from Dike to Palmdale Two (MP 417.3) and then to assist a westbound train, Extra 8240 West, between Palmdale Two and Oban (MP 399.9). The helper engineer had been informed by the engineer whom he had relieved that the dynamic brakes on unit SP 8317 were inoperative. The movement from Palmdale Two to Oban was uneventful, and the crewmembers had no concern about the operation of the train. At about 5:06 a.m., the dispatcher instructed the helper engineer to couple the helper locomotive onto the rear of an eastbound train, Extra 7551 East, that was waiting in a siding at that location for helper service through the Cajon Pass.
The helper engineer testified that he did not receive any information from either the head-end engineer or the dispatcher regarding the tonnage of Extra 7551 East nor did he request that information. There was no SP requirement that he be furnished that information. He stated that he did not normally operate over this territory and, therefore, did not know if it was customary to receive that information. He stated further that for the territory over which he normally operated, he usually received that information, and that if he did not, he would request it.
Movement of Extra 7551 East From Oban to Hiland.—After the helper engineer radioed the head-end engineer and informed him that the helper locomotive was coupled onto the rear of Extra 7551 East, an airbrake test was performed; neither engineer noted any deficiencies in the operation of the brakes during the test. Upon receiving a clear signal, Extra 7551 East departed the siding at Oban. At about 5:30 a.m., the helper engineer
- The method for positively determining if dynamic brakes are operating is by observing the amperage reading in each locomotive unit. See Mechanical Information for additional discussion.