Photos: Munitions explosion on Tucson-bound train in 1973
50 years ago, nearly 2,600 500-pound U.S. Navy bombs on a train detonated in three massive explosions near Dragoon, Ariz.
The National Transportation Safety Board determined that sparking brakes ignited wood and sodium nitrate residue in a boxcar.
All photos © Arizona Daily Star or Tucson Citizen
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Torn open by exploding 500-pound bombs, a Southern Pacific boxcar sends a shower of sparks from its blazing interior. Railroad officials said 12 cars were demolished in the munitions blast. The shipment included 2,600 bombs and was minutes away from the town of Benson. May 24, 1973. Lew Elliott / Tucson Citizen
Exploding 500-pound bombs tore a 115-foot wide crater in the Cochise County countryside, stopping a Southern Pacific freight in its tracks southeast of Benson. May 24, 1973. Explosions continued until 1:15am on May 25. Lew Elliott / Tucson Citizen.
A mushroom cloud created as hundreds of 500-pound bombs detonate during a series of explosions. An Air Force pilot flying nearby estimated the main smoke cloud to be 3,000 feet high. Scene of a munitions explosion on a Southern Pacific RR train near Benson on May 24-25, 1973. Benjie Sanders / Arizona Daily Star
Exposed in the light of flames from that ripped a 107-car Southern Pacific freight train, a 500-pound bomb lies in the desert southeast of Benson. Of the 2,600 bombs on the train, 500 were recovered unexploded. The NTSB determined that sparking brakes created a smoldering fire in the floorboards of the boxcar, which ignited the bombs. May 25, 1973. Lew Elliott / Tucson Citizen.
One of nearly 500 unexploded Mk-82 500-pound bombs that lie alongside the Southern Pacific Railroad tracks east of Benson where they were retrieved from the wreckage of a 107-car freight train. Bombs were found as far as one mile from the main crater area. Thursday. May 26, 1973. Douglas Kreutz / Tucson Citizen.
Southern Pacific Railroad track-repair crews quickly restored a 460-foot stretch of track destroyed by bomb explosions east of Benson. Bomb craters were filled, new rails were laid, and the line was opened to train traffic by 8:45pm on May 26, 1973. About 24 trains had passed over the new track the following morning, according to railroad officials. Douglas Kreutz / Tucson Citizen.
Bombs tore a 115-feet wide crater near Dragoon. May 25, 1973. The blast registered as high as 1.6 on the Richter scale in Tucson. Bruce Hopkins / Tucson Citizen.
Hundreds of unexploded Navy bombs lie alongside the Southern Pacific Railroad tracks east of Benson where they were retrieved from the wreckage of a 107-car freight train. Most of the train's cargo of some 1 1/2 million pounds of bombs went up in smoke in a explosion on May 24, 1973. Douglas Kreutz / Tucson Citizen.
Scene of a munitions explosion on a Southern Pacific RR train near Benson on May 24-25, 1973. The main blast created a crater 115 feet long and 25 feet deep. Art Grasberger / Arizona Daily Star
Scene of a munitions explosion on a Southern Pacific RR train near Benson on May 24-25, 1973, as an Explosive Ordinance Detail from Ft. Huachuca enters the scene. Art Grasberger / Arizona Daily Star
Scene of a munitions explosion on a Southern Pacific RR train near Benson on May 24-25, 1973. The main explosion scorched the desert for 1/4 mile in all directions. Art Grasberger / Arizona Daily Star
Thirteen Southern Pacific Railroad freight cars- 12 of them loaded with 500-pound bombs bound for California- literally were blown to bits during a two-hour series of explosions 15 miles south of Benson. Windows in a home five miles away were shattered by the main blast. May 25, 1973. Bruce Hopkins / Tucson Citizen.
The main explosion created a 115-feet wide by 25-feet deep crater the desert, stopping this Southern Pacific freight in its tracks southeast of Benson. May 25, 1973. There were three massive explosions. Bruce Hopkins / Tucson Citizen
About 500 of the 2,600 Mk-82 500-pound bombs were recovered unexploded after a series of explosions on a Southern Pacific RR train near Benson on May 24-25, 1973. The bombs consisted of 80-percent TNT and 20-percent aluminum. Art Grasberger / Arizona Daily Star
A series of explosions destroyed 12 munitions cars and 460 feet of railroad roadbed after a series of explosions on an SP train on May 24, 1973 near Dragoon, Ariz. The blast scattered train parts up to 3/4 mile. Art Grasberger / Arizona Daily Star
Southern Pacific Railroad track-repair crews quickly restored a 460-foot stretch of track destroyed by bomb explosions east of Benson. The train was minutes away from Benson when crews pulled the emergency brakes upon seeing the first explosions on May 24, 1973. Douglas Kreutz / Tucson Citizen.
Rick Wiley
Photo editor
Arizona bill seeks shorter trains to cut railroad crossing waitFor Star subscribers: HB 2531 would limit the length of trains going through the state to 8,500 feet. That's about 1.6 miles long.
Architect Josias Joesler established a style that became emblematic of Tucson in the early 20th century.