RAILWAY OCCURRENCE REPORT CN NORTH AMERICA RUNAWAY TRAIN MILE 175, GRANDE CACHE SUBDIVISION LATORNELL, ALBERTA 18 JANUARY 1994 REPORT NUMBER R94V0006 Transportation Safety Board Bureau de la sécurité des transports of Canada du Canada The Transportation Safety Board of Canada (TSB) investigated this occurrence for the purpose of advancing transportation safety. It is not the function of the Board to assign fault or determine civil or criminal liability. Railway Occurrence Report CN North America Runaway Train Mile 175, Grande Cache Subdivision Latornell, Alberta 18 January 1994 Report Number R94V0006 Synopsis CN North America (CN) freight train No. 459-GP-18, en route from Grande Prairie, Alberta, to Jasper, Alberta, was proceeding at approximately 11 mph when it crested a hill at Mile 174.8 of the Grande Cache Subdivision. The train began to accelerate as it moved over the descending grade towards a 10-mph permanent speed restriction in effect from Mile 173.2 to Mile 169.7. Several futile attempts were made by the locomotive engineer to control the acceleration using the service brake when, at 16 mph, an attempt was made to bring the train to a stop with an emergency brake application. This proved unsuccessful and, when the train reached a speed of approximately 28 mph, the train crew abandoned the train. The unmanned train negotiated the 10-mph speed-restricted area and eventually came to a stop at about Mile 167. No injuries or damage resulted from this occurrence. The Board determined that loss of control of the train occurred because the air brake system had not been periodically conditioned to nullify the effects of snow and ice build-up on the brake shoes, and because the dynamic braking system was inoperative. Contributing to the occurrence was the fact that at least part of such snow and ice and its effect, if any, on the brakes was not recorded by the inspector or revealed to the locomotive engineer prior to departure and the fact that the train departed without functioning dynamic brakes. Ce rapport est également disponible en français. TABLE OF CONTENTS Table of Contents Page 1.0 Factual Information ..................................................... 1 1.1 The Incident .......................................................... 1 1.2 Train Information...................................................... 1 1.3 Personnel Information .................................................. 2 1.4 Particulars of the Track.................................................. 2 1.5 Method of Train Control ................................................ 2 1.6 Weather .............................................................. 2 1.7 Event Recorder Information ............................................. 2 1.8 Tests and Research ..................................................... 2 1.9 Other Information...................................................... 3 1.9.1 Air Brake Requirements ................................................. 3 1.9.1.1 Inspection and Testing of Locomotives .................................... 3 1.9.1.2 Inspection and Testing of Train Consists ................................... 3 1.9.1.3 Other Requirements .................................................... 4 1.9.2 Dynamic Brake Operation ............................................... 4 1.9.3 Lead Locomotive CN5416 ............................................... 4 1.9.4 Train Brake Inspection.................................................. 5 1.9.5 Snow Removal......................................................... 5 2.0 Analysis ................................................................... 7 2.1 Introduction........................................................... 7 2.2 Consideration of the Facts............................................... 7 2.2.1 Initial Brake Inspection.................................................. 7 2.2.2 Running Brake Test..................................................... 7 2.2.3 Locomotive Brake Tests................................................. 7 2.2.4 Brake Performance Before Mile 174.5 ...................................... 8 2.2.5 Impact of No Dynamic Braking on Speed Control ........................... 8 3.0 Conclusions .............................................................. 9 3.1 Findings.............................................................. 9 3.2 Cause ................................................................ 9 TRANSPORTATION SAFETY BOARD iii TABLE OF CONTENTS 4.0 Safety Action ............................................................. 11 4.1 Action Taken.......................................................... 11 4.1.1 Dynamic Brake Testing.................................................. 11 4.1.2 Alberta District Winter Operating Plan..................................... 11 iv TRANSPORTATION SAFETY BOARD FACTUAL INFORMATION 1.0 Factual Information the train, initiated an emergency broadcast on a portable radio, advising the rail traffic controller (RTC) in Edmonton, Alberta, of the abandoned 1.1 The Incident runaway train. On 18 January 1994, CN North America (CN) The train travelled approximately train No. 459-GP-18, designated 6.2 miles, reaching speeds of approximately Extra 4516 South (the train), departed Grande 44 mph, before it came to a stop at about Prairie, Alberta, Mile 231 of the Grande Cache Mile 167. Subdivision at approximately 1215 mountain standard time (MST) destined for Jasper, The crew members were rescued by Alberta. Grande Prairie had been the helicopter around 1700 MST, approximately originating station. four miles southward from the point where they had jumped from the train. They were not At Mile 193.0, the train was brought injured and the train had come to a stop to a stop and a roll-by inspection was without damage. performed by the train crew, as required for trains handling dangerous goods on 1.2 Train Information subdivisions without Hot Box and Dragging Equipment Detectors. A heavy build-up of The train, powered by three diesel locomotives, snow and ice on the brake rigging was noticed was hauling 63 loads, four empties, and was during this inspection. From this point and for operated cabooseless. It weighed approximately 51 minutes, the train traversed approximately 7,899 tons and was about an ascending grade to Mile 175.6 while 4,066 feet in length. ploughing several inches of snow. As the train approached Mile 174.8, the locomotive engineer reduced the throttle and applied a minimum service brake application. At Mile 175.6, the grade changed to a descending grade. The train crested the top of the ascending grade at approximately 11 mph, 1.3 Personnel Information approaching a 10-mph speed restriction from Mile 173.2 to Mile 169.7. The train began to The crew included a conductor and a accelerate and the locomotive engineer locomotive engineer. attempted to maintain the speed of 10 mph through throttle modulation and a minimum Both crew members were familiar service brake application. As the train speed with the subdivision, were qualified for the continued to increase, an additional service requirements of their respective positions and brake application was made in an attempt to met fitness and rest standards established to arrest the acceleration. ensure the safe operation of trains. The locomotive engineer, realizing that the service brake applications were 1.4 Particulars of the Track unsuccessful, made an emergency brake application; however, the train continued to The authorized speed on the Grande Cache accelerate. When the train speed reached Subdivision is 30 mph. From Mile 189.0 to 28 mph, in the vicinity of Mile 173.4 at Mile 175.6, the grade is ascending at approximately 1504 MST, the crew members approximately 1.0 per cent. At Mile 175.6, the abandoned the train as they feared that it would grade crests and begins descending at 1.52 per not safely negotiate the 10-mph speed- cent for approximately 7.4 miles. Between restricted area. The crew, after jumping from Mile 173.2 and Mile 169.7, a permanent slow TRANSPORTATION SAFETY BOARD 1 FACTUAL INFORMATION order of 10 mph is in effect because of the 100 per cent effective brakes (and no dynamic descending grade and numerous curves. braking), train speed on the descending grade could have theoretically been maintained at 1.5 Method of Train Control 10 mph with the service brake. When the occurrence was recreated with no brakes, the Train movements on the Grande Cache train reached theoretical speeds in excess of Subdivision are governed by the Occupancy 90 mph. Once the recreation was adjusted to Control System authorized by the Canadian simulate actual speeds and conditions, the Rail Operating Rules and supervised by the recreation indicated that the train was operating RTC located in Edmonton. with approximately 32 per cent of its theoretical braking capability. The computer analysis also indicated that, had a service brake application 1.6 Weather and varying amounts of dynamic braking been made, even with a 32 per cent train braking The temperature was minus 29 degrees Celsius, capability, train speed could have been and there were moderate winds. A heavy snow controlled on the descending grade. storm had just passed through the area depositing 11 to 15 cm of fresh snow. 1.9 Other Information 1.7 Event Recorder Information 1.9.1 Air Brake Requirements The event recorder transcript from the lead Before departing an originating terminal, a locomotive revealed that the No. 1 traction number of safety-related inspections and tests motor was cut out (disabled) before
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