On May 12, 1989, one of the most devastating accidents in the history of the Southern Pacific Railroad occurred in a northwest suburb of San Bernardino, California along the relatively new (opened in 1967) Palmdale-Colton "Cut-Off" line at the foot of the Cajon Pass grade.  Southern Pacific train 01-MJLBP-12 (Mojave, CA to Long Beach, CA Unit Potash train), with 69 hopper cars loaded with potash south of Mojave at Rosamond, CA lost control while descending the 2.2% grade on the south slope of Cajon Pass.   All 69 cars and six locomotives derailed when the train reached a curve next to the suburban San Bernardino neighborhood along Duffy street near Highland Avenue.  The runaway train reached speeds in excess of 90 MPH (the maximum recordable speed on the onboard "black box" speed recorder) in the descent of the 23 mile grade.   Killed in the accident were SP Conductor Everett S. Crown and Brakeman Allan R. Riess.  Also killed in trackside homes were two children ages 7 and 9, with eleven additional people injured.  Seven homes were destroyed outright by the accident, and four more were damaged and eventually torn down.  In response to the accident, Southern Pacific agreed to pay all moving, storage and temporary housing costs for displaced residents as well as purchase the eleven homes damaged or destroyed in the accident.  In addition, Southern Pacific agreed to reimburse the City of San Bernardino for all expenses incurred in response to the accident, as well as any judgements against the city resulting from the accident.  Southern Pacific also agreed to pay for inspection and necessary repair to a 14-inch petroleum pipeline buried fourteen feet beneath the accident site.

A Second catastrophe struck the accident ravaged neighborhood two weeks later on May 25th, when the petroleum pipeline that parallelled the rail line ruptured and exploded, destroying eleven more homes and killing two more residents.  Investigation after the pipeline explosion found that CalNev Pipelines did not adequately inspect the pipeline after the accident.

The cause of the accident was complex.  The train weight was estimated (no car scales exist in Rosamond) to be 6,151 tons, which is the information the train's crew had.   Later computations made by weighing similarly loaded cars estimated the actual train weight to be near 8,970 tons.  In addition, the train's headend and helper power each had at least one unit with inoperable dynamic brakes.  This left the train with sufficient braking power for the reported weight, but not enough for the actual weight.

In response to the loss of two of their co-workers, Southern Pacific and its employees erected a large white cross at the peak of the hill in the middle of the Tehachapi Loop.   In addition, a memorial plaque and marble bench were placed trackside on the loop with the bench facing the hill and cross.  If you visit the location, please remember to pause and reflect.  Not only on the lives of the two railroaders that were lost in this accident, but on those that live on and work their trade every day on the nation's railroads.