The San Bernardino train disaster (sometimes known as the Duffy Street incident or the 1989 Cajon Pass Runaway) was a combination of two separate but related incidents that occurred in San Bernardino, California, United States: a runaway train derailment on May 12, 1989; and the subsequent failure on May 25, 1989, of the Calnev Pipeline, a petroleum pipeline adjacent to the tracks which was damaged by earth-moving equipment during the crash cleanup.

Train derailment On May 12, 1989, at 7:36 a.m., a 6-locomotive/69-car Southern Pacific freight train (SP 7551 East, computer symbol 1 MJLBP-11) transporting trona lost control while descending Cajon Pass, derailed on an elevated curve and plowed into a residential area on Duffy Street. The location is just northeast of where the 210 Foothill Freeway crosses the Lytle Creek wash.

The conductor, head-end brakeman, and two residents were killed in the wreck. Seven houses on the street immediately next to the tracks were demolished by the wreck, as were the lead locomotives and all of the freight cars. Clerks in Mojave had miscalculated the weight of the train, while the engineer and crew at the head end were unaware that one of the rear helper engines had inoperative dynamic brakes. Hence there was not enough dynamic braking force available to maintain control of train speed during the descent. When the helper engineer realized that the train speed was not being adequately controlled, he made an emergency brake application, which deactivated dynamic braking, resulting in a runaway condition. The train reached a speed of about before jumping the tracks on an elevated curve that had a posted speed limit of next to Duffy Street, sending the head-end locomotives and several cars off the high railroad bed and into houses on the street below, completely demolishing them.

Data from the locomotives' "black boxes" (event recorders) showed that the third head end locomotive's dynamic brakes were not functioning at all, although the sound of the cooling fans misled crews into believing dynamic braking was functional. It was also determined after the wreck that the engineer operating the helper locomotives knew of the faulty dynamic brakes on one of his units, but did not communicate that information to the head end crew. The combination of weight miscalculation, poor communication and faulty brake equipment resulted in a total train weight that was too great to adequately control speed on the downhill grade. Once dynamic braking had been defeated by the helper engineer's emergency brake application, the enormous weight of the heavily loaded cars caused rapid acceleration that could not be resisted solely by mechanical braking. The train catapulted from the 35 mph curve next to Duffy Street at 110 mph, scattering locomotives and cars, as well as lading. Leading the train was Southern Pacific SD40T-2 8278, Southern Pacific SD45Rs 7551 and 7549, and Southern Pacific SD45T-2 9340, which were on the head end, 69 hopper cars loaded with trona, and Southern Pacific SD40T-2 8317 and Southern Pacific SD45R 7443 on the helper end.

Train and helper crews of Southern Pacific 7551 East

The crew that was called for train 7551 East were as follows: Frank Holland, Engineer (age 33) Everett Crown,† Conductor (age 35) Allan Riess,† Brakeman on 3rd locomotive (age 43) Lawrence Hill, Engineer on helper unit 7443 (age 42) Robert Waterbury, Brakeman on helper unit 7443 (age 57) (†=Killed in the wreck.)

Killed in the wreck were Conductor Crown (fatally crushed in the nose of unit SP 8278) and Brakeman Riess (fatally crushed in the cab of unit SP 7549), along with two young boys, Jason Thompson (age 10 years) and Tyson White (age 7 years), who were crushed and asphyxiated when the train destroyed one of the houses on Duffy Street. One person, Chris Shaw, was trapped in one of the houses and was pulled out 13 hours after the accident, he had a broken leg.

Engineer Holland remained in his seat at the control stand in unit SP 8278 at the head of the train and suffered several cracked ribs along with a punctured lung. However, he was able to crawl out of his wrecked locomotive and was helped down by eyewitnesses on the scene. Engineer Hill and Brakeman Waterbury, who were in the helper locomotives, received minor injuries.

Pipeline rupture and fire

Buried six feet underground alongside the track is a 14-inch high-pressure petroleum pipeline operated by Calnev Pipeline. The pipeline was marked with stakes during cleanup to avoid the risk of it being accidentally damaged. Pipeline officials remained on site as safety observers during the cleanup of the rail cars, but not during the cleanup of the trona material. Service on the track where the derailment happened was restored four days after the crash. Thirteen days after the train wreck on May 25, 1989, at 8:05 a.m., shortly after eyewitnesses heard a train pass through the derailment site, the pipeline burst at a point on the curve where the derailment happened, showering the neighborhood with gasoline, which ignited into a large fire that burned for close to seven hours and emitted a plume of flames three hundred feet into the air. By the time the fire was out, it had fatally burned two people, and destroyed eleven more houses and 21 cars. Of the houses destroyed, five were directly across the street from houses that had been destroyed in the derailment, while another was the only house on the track side of Duffy Street to have been spared damage during the derailment. Four more houses received moderate smoke and fire damage, while three others had only smoke damage. The total property damage was US$14.3 million (equivalent to $ million in ), with more of this damage resulting from the fire than from the train derailment, although there were more fatalities from the derailment.

Aftermath

Attempts to have the Calnev pipeline kept shut off after its failure were unsuccessful.

Many residents received settlements from Southern Pacific and/or Calnev and moved after this disaster. The plots on the south side of Duffy Street closest to the rail line were rezoned as open space by the city so they would not be rebuilt. Other nearby plots which could be redeveloped sat empty for years, though as of 2016, at least three houses had been rebuilt there.

Southern Pacific also changed its cargo weight procedures, which required that the clerks assume that every freight car on every train was carrying the maximum load it was designed to carry if the submitted paperwork did not indicate a weight. By assuming the maximum weight of the train, that would guarantee that the dispatcher would assign at least the minimum number of locomotives needed to ensure that the train would have enough braking capacity needed to keep the train under control on steep grades.

Seven years after the accident, Southern Pacific was bought up by Union Pacific, which still runs trains over the rails where the derailment happened.

Disposal of the train's equipment

SP #8278, SP #7551, SP #7549 and SP #9340 were damaged beyond repair. They were sold for parts to Precision National and scrapped at the crash site.

Both helper units derailed, but were still operable. SP 8317 was sold to Precision National, repaired, then resold to Helm Leasing for continued service. It was scrapped in 2013. SP #7443 was repaired and repainted by SP and returned to service. It was finally retired on March 17, 2000 and sold to National Railway Equipment Company, who rebuilt it with 5′6″ gauge trucks for MRS Logística (in Brazil) #5313-1.

All 69 hopper cars were destroyed and scrapped at the crash site.

As a result of this and other runaway incidents involving locomotives with dynamic braking, the Federal Railroad Administration reversed its mandate that dynamic braking be disabled when train brakes are placed in emergency. The mandate now is that they must all remain functional.

Investigation

Part 1: Train derailment

Much of the NTSB's investigation into the two disasters was focused on the activities surrounding the derailment.

SP MJLBP1-11 was carrying trona that had been mined and loaded onto the freight cars for shipment to a buyer. The shipment would move by rail to the Port of Los Angeles, then by ship to Colombia, South America. This would be the second such shipment. The buyer had purchased 6,900 tons of trona; thus the mining company, Lake Minerals, contracted for 69 100-ton coal hopper cars (which had a combination of D&RGW and SP reporting marks), which were to be loaded by an outside contractor at Rosamond. When the mining company turned in the final contract to the clerk (Thomas Blair) for the bill of lading, they had not filled in any weight, under the assumption that the railroad would know that they had filled the 100-ton cars to capacity. The clerk filled in the bill of lading as 60 tons per hopper car, going by a visual comparison of 100 tons of coal. As a result, the train was listed as weighing about 6,151 tons total (2,011 tons from the freight cars themselves, 4,140 tons of cargo), significantly lighter than its actual weight (Warren, 3).

At 9:00 p.m. on May 11, a three-man crew consisting of Frank Holland, an engineer; Everett Crown, a conductor; and Allan Riess, a brakeman, were brought on duty at SP's Bakersfield yard. They were transported by company van to Mojave to take charge of a three-unit set of locomotives, consisting of SP 7551, SP 7549 (both EMD SD45R units) and SP 9340 (an EMD SD45T-2). While at Mojave, the crew obtained the necessary paperwork for their train, including a Car and Tonnage Profile (a printout generated by SP's TOPS computer system that showed, among other things, the assumed train weight of 6,151 tons). Upon boarding the locomotives, it was discovered that the head unit, #7551, was dead and could not be started. The crew was then instructed to take unit SP 8278 (an EMD SD40T-2 "Tunnel Motor") from another consist and add it to theirs, ahead of the dead 7551.

The crew departed Mojave at 12:15 a.m. on May 12, and headed south (railroad direction east) approximately three miles to Fleta, where they were to pick up the 69 freight cars. Due to maintenance equipment being parked on the track at the south end of the Fleta siding, it was necessary for the train crew to pick up the cars from the north end, take them back to Mojave and run around them, before heading south to Palmdale, where it was originally intended to pick up an additional helper that would be placed on the rear of the train to aid in braking after cresting Cajon Pass.

After a shift change in the train dispatcher's office, the new dispatcher correctly recalculated the tonnage of the train to be approximately 8,900 tons, based on his previous experience with these types of moves. Braking ability diminishes exponentially for every degree of grade – at a 2.2% grade, the dynamic brakes of one fully operational locomotive was capable of maintaining the speed of 1,700 to 1,800 tons of weight (either in freight cars or freight) at a speed of . Dynamic braking ability is most effective near a speed of and diminishes if the train travels slower or faster than this optimal speed, so engineers try to maintain speeds between on steep grades. The dispatcher determined that they would need the dynamic brakes of 5.23 functional engines (6 total) to maintain this optimal speed between , so picking up only the one additional helper locomotive at Palmdale, as originally planned, would not provide sufficient dynamic braking effort for the 2.2% grade on the west side of Cajon Pass where the derailment happened, so instead of adding the single unit at Palmdale, the dispatcher ordered a two-unit helper set dispatched from the helper pool in West Colton, California.