circuits were found free of defect and they functioned as designed with the signals displaying proper aspects. Circuiting for the locomotive cab signals was also tested and found to be operating in accordance with the wayside signals.

ANALYSIS

After passing a clear signal more than 10 miles east of the accident location, the engineer of Extra 3449 West was in a position to observe signal 6299-1, which would have displayed an "advance approach" aspect. While this signal may have changed to a "clear" aspect before Extra 3449 West reached it, the next signal (6319-1) would have continuously displayed an "advance approach." An alert and experienced engineer should have realized that the succession of "advance approach" aspects meant that another westbound train was moving through the signal blocks ahead. The radio transmission which the engineer of Extra 3449 West said he had heard before his train passed signal 6299-1 was also an indication that a train was ahead.

By the time Extra 3449 West reached signal 6345-1, the engineer was required to have reduced his train's speed to 40 mph. Yet the locomotive speed recorder tape indicated that the train passed the signal at 62 mph. The "approach" aspect displayed by signal 6345-1 required immediate reduction to 30 mph and the ability to stop short of signal 6367-1, yet the train passed this signal, which would have displayed a "stop and proceed" aspect, at 52 mph. The red marker light on the rear of Extra 3055 West should have been plainly visible to the engineer and head brakeman of Extra 3449 West when it was still more than 2,000 feet away. Yet Extra 3449 West struck the rear of the slowly moving coal train at a speed of 48 mph. At no time did the engineer take action to reduce from full throttle operation or to initiate any braking action. The gradual deceleration of his train was due entirely to the effect of the long ascending grade approaching Ramsey.

As the head end of Extra 3449 West passed each of the progressively more restrictive signal aspects, they would have been repeated by the locomotive cab signals. Failure to acknowledge these changes of the cab signals would have caused the cab signal warning whistle to sound continuously. But neither the engineer nor the head brakeman could have heard the whistle because it had been muted with a rag before they boarded the train at Cheyenne. The conspicuous location of the whistle on the forward cab wall and the large rag tied around it, as well as the fact that the whistle emitted no discernible sound, make it unlikely that the engineer and brakeman did not know that the whistle had been muted from the time they left Cheyenne. It is unfortunate that because these men had failed to correct the muted whistle, they also deprived themselves of the protection the device was intended to provide.

The engineer contended that all of the signals approaching the accident location displayed "clear" aspects. Even if this were so, his train was moving too fast to have slowed in time to observe the 40-mph slow order beginning 3,020 feet beyond the point of impact. The engineer stated he and the head brakeman saw the caboose of Extra 3055 West when it was still about 1,400 feet ahead. If this were

so and had he immediately applied the brakes in emergency with his train on a 0.70 percent ascending grade, and with Extra 3055 West moving at about 10 mph, such prompt action could have substantially reduced the speed of his train and greatly decreased the effect of the collision. With reduction of speed and an attempt to alert the crew of Extra 3055 West by radio, blowing of the whistle, or on-off manipulation of the headlight switch, both men on the rear of Extra 3055 West might have had time to successfully escape from the caboose. It is inconceivable that an alert and experienced engineer would take no action under the circumstances. Yet the last known action on the part of the engineer of Extra 3449 West was the dimming of his locomotive's headlight for an opposing train 17 minutes before the accident occurred.

The only evidence to support the contention of the engineer of Extra 3449 West that the signals approaching the accident location were "clear" was the inconsistent testimony of the conductor and rear brakeman of his train. Due to the length of Extra 3449 West, the two crewmembers on the caboose could only have seen signals 6299-1 and 6319-1 before their locomotive units passed them. Three days after the accident, the conductor said he didn't see any of the signals. Later, he recalled seeing signal 6319-1 display a "clear" aspect. The rear brakeman originally claimed to have seen a "clear" aspect on signal 6319-1. Ultimately, he admitted he didn't see the signal.

The wayside signals approaching Ramsey displayed the proper aspects for the intended routing and movement of Extra 3055 West, and these were properly repeated by that train's locomotive cab signals. Signals 6319-1, 6345-1, and 6367-1 also operated properly after the accident when the locomotive units of the Supervan train were operated over No. 1 track to the accident location. Postaccident tests conducted in the presence of FRA inspectors failed to reveal any defects in the relays and circuitry that might have caused any signal to display an improper indication. No defects were found in the locomotive cab signal circuitry. Therefore, the Safety Board concludes that the signals were operating properly and were displaying progressively more restrictive aspects which the engineer of Extra 3449 West did not obey.

The insistence of the three surviving crewmembers of Extra 3449 West that they passed the last eastbound train 4 or 5 miles east of Ramsey instead of east of Medicine Bow was not supported by the CTC recording graph, statements of the crewmembers of other trains, and the registered times the eastbound trains passed the open station at Hanna.

It is possible that the last signals the engineer and head brakeman actually observed were the clear signals passed at and immediately west of Medicine Bow. For the last 15 miles of its run, Extra 3449 West was laboring in full throttle. The cab windows and doors were closed and the cab heater was on. The engineer had only napped briefly during the 18 hours preceding the accident and may have dozed off. The mere weight of the engineer's foot on the deadman pedal was sufficient to keep it depressed. The one safety device the cab signal whistle - that could have alerted the men had been effectively muted so that it could no longer serve its intended purpose.

This accident demonstrates that the purpose of the cab signal warning whistle can be easily and effectively eliminated, and that the device, by itself, is an inadequate means of assuring the engineer's compliance with restrictive signal indications. Had the UP's locomotive cab signal system included a provision for automatic penalty application of the automatic brake system when the engineer fails to acknowledge a restrictive cab signal indication, Extra 3449 West would have been stopped long before it reached Ramsey, and the collision would not have occurred.

The engineer and head brakeman of Extra 3055 West did not know what had caused their train to go into emergency and had heard nothing from Extra 3449 West. Yet, the engineer used his radio to warn an oncoming eastbound train while the brakeman alighted and put out fusees as required. The timely action of these men could have been critical in preventing an even greater catastrophe. Had the derailed cars that obstructed the No. 2 track not shunted the signal circuit, the eastbound train would have collided with the wreckage. The head brakeman was new to the UP and the territory, yet he instinctively acted to protect the adjacent tracks. The brakeman's performance was in contrast to that of the experienced crewmembers of Extra 3449 West. Although these men clearly understood that a fast-moving train was not far behind them and could very well have been routed to overtake them, they failed to protect the No. 2 track and maintained absolute radio silence for 27 minutes after the accident.

Although the UP says it requires its engineers and conductors to attend instruction and reexamination classes in the operating rules once every 2 years, the engineer of Extra 3449 West had not received such training since 1973 -prior to his qualification on the Cheyenne-Rawlins territory. The rear brakeman on the same crew, a promoted conductor, had not attended a rules class since 1975.

The speed recorder was very helpful in determining the actual speed of the train as it approached the point of the collision. This in turn provided information of the activities of the crewmembers in the locomotive. However, an events recorder would have been more beneficial in providing this information.

CONCLUSIONS

Findings

1.

2.

The wayside block signals and the circuitry for the locomotive cab signal system which governed the movement of Extra 3449 West approaching the accident location functioned as intended.

The engineer of Extra 3449 West failed to operate his train in compliance with restrictive aspects displayed by wayside signals 6319-1, 6345-1, and 6367-1, which were repeated by his locomotive cab signals.

3.

4.

5.

6.

The engineer of Extra 3449 West failed to take any action to stop his train after he was in a position to see the train ahead, or to use his radio or whistle to warn the crew of Extra 3055 West.

The cab signal warning whistle had been muted before Extra 3449 West arrived at Cheyenne, a condition which the crew that boarded the train at Cheyenne failed to correct.

The muting of the cab signal warning whistle made it impossible for the engineer and head brakeman to hear it, rendering ineffective the intended purpose of this safety device.

Had the UP's locomotive cab signal system included a provision for the automatic penalty application of the automatic airbrake system in the event of the engineer's failure to acknowledge a restrictive cab signal indication, Extra 3449 West would have been stopped short of the preceding train and the accident would not have occurred.

Probable Cause

The National Transportation Safety Board determines that the probable cause of the accident was the failure of the engineer of Extra 3449 West to comply with a series of restrictive wayside signals, repeated by locomotive cab signals, including a "stop-and-proceed" aspect 6,303 feet from the point of collision. Contributing to the accident was the unauthorized muting of the cab signal warning whistle so that it could not alert the engineer when a more restrictive signal was passed.

RECOMMENDATIONS

During its investigation of this accident, the National Transportation Safety Board made the following recommendation to the Union Pacific Railroad on July 5, 1979.

"Modify its locomotive cab signal apparatus to provide for an automatic penalty application of the automatic airbrake system whenever the engineer fails to acknowledge a more restrictive signal indication within the specified time. (Class II, Priority Action) (R-79-41)"

On January 25, 1976, as a result of its investigation of an accident in Meeker, Louisiana, on May 30, 1975, 6/ the Safety Board recommended that the Federal Railroad Administration:

6/ "Railroad Accident Report - Rear-End Collision of two Texas and Pacific Railway Company Freight Trains, Meeker, Louisiana, May 30, 1975" (NTSB-RAR75-9).

"Promulgate regulations to require an adequate backup system for mainline freight trains that will insure that a train is controlled as required on the signal system in the event that the engineer fails to do so. (R-76-3) (Long-Term Followup)

The FRA has not acted on recommendation R-76-3, and no regulations have been promulgated. The Union Pacific's compliance with recommendation R-79-41 above would accomplish the intent of recommendation R-76-3 for at least that railroad's operations.