About 4:38 p.m., on December 12, 1978, the sixth and seventh cars of a New York City Transit Authority subway train designated "CC" 4:06 p.m. derailed within moments after departing 59th Street station. Twenty-two persons were injured, and property damage was estimated to be $667,500. While the Safety Board was investigating this accident, three other trains derailed from what appeared to be similar causes. Therefore, the investigation was expanded to include all four accidents. The National Transportation Safety Board determines that the probable cause of each of the four accidents was a cracked wheel which had resulted from extensive overheating. Contributing to the cause of the overheating of the wheels was the partial application of a handbrake. Because of a lack of adequate inspection procedures, the New York City Transit Authority employees failed to detect the partially applied handbrake and the thermally damaged wheels before they cracked. About 4:38 p.m., on December 12, 1978, the sixth and seventh cars of a New York City Transit Authority subway train designated "CC" 4:06 p.m. derailed within moments after departing 59th Street station. Twenty-two persons were injured, and property damage was estimated to be $667,500. While the Safety Board was investigating this accident, three other trains derailed from what appeared to be similar causes. Therefore, the investigation was expanded to include all four accidents. The other derailments were: (1) At 8:08 a.m. on January 15, 1979, when the fourth car of an "A" train derailed north of Rockaway Avenue; (2) at 7:23 p.m. on February 14, 1979, when the seventh car of an "E" train derailed at 53rd Street; and (3) at 7:04 a.m. on March 21, 1979, when the first car of a "CC" train derailed at 14th Street. The National Transportation Safety Board determines that the probable cause of each of the four accidents was a cracked wheel which had resulted from extensive overheating. Contributing to the cause of the overheating of the wheels was the partial application of a handbrake. Because of a lack of adequate inspection procedures, the New York City Transit Authority employees failed to detect the partially applied handbrake and the thermally damaged wheels before they cracked. INVESTIGATION The Accidents On December 12, 1978, New York City Transit Authority (NYCTA) subway train designated "CC" 4:06 p.m. departed southbound from Bedford Park on time. The train, consisting of eight cars, continued southward making its scheduled station stops. At 170th Street, 2.7 miles south of Bedford Park, passengers in the sixth car became concerned because of the car's bumping and the presence of smoke inside the car. Because of their concern, they began to move from the sixth car to other cars in the train. One woman who had boarded the eighth car of the train at 145th Street stated that the train was going up and down as if it were riding on a bumpy road. She said she smelled an odor like that of tar or oil. Two passengers who boarded the sixth car of the train at 72d Street said that the train bounced them around. One of these passengers said it felt like a wheel was coming off. A passenger who boarded the sixth car at 96th Street noticed smoke coming from under the car. Because of the bumpy ride, he moved forward one car at 86th Street, to the car from which the conductor was operating the doors. He did not tell the conductor about the conditions in the sixth car. A passenger who boarded the sixth car of the train at 59th Street said the car was filled with a gray haze, and there was was an odor like that created by an electrical short circuit. Furthermore, she said she heard hissing and popping sounds like an electrical short circuit coming from between the cars. She said the ride was rough as the train left the station, and it seemed as though the wheels were flat. She said she saw sparks between the sixth and seventh cars. Earlier, as the train was leaving the 125th Street station, 6 miles south of Bedford Park, the platform conductor had seen smoke coming from under the sixth car. This conductor notified the dispatcher at 125th Street who, in turn, arranged for a road car inspector to meet the train at the 59th Street station. Both the motorman of the train and the dispatcher had operating radios; however, the dispatcher did not notify the motorman about the smoke issuing from his train. As the train arrived at the 59th Street station, the road car inspector was waiting on the platform. When the train stopped he indicated to the conductor to hold the doors open so that the train would not move. The road car inspector then looked down along the side of the sixth car between the car and the platform. He then stepped onto the end of the car, crossed over, and looked down along the other side of the car and the tunnel wall. He later said that he did not detect any defects on the sixth car. Both the motorman and the train conductor said that they did not talk with the road car inspector and that he did not notify them of the smoke emission report. The road car inspector then gave an "okay" to the conductor, by hand signal, for the train to proceed, and he boarded the sixth car to continue to check for the problem. He said that he did not see any smoke coming from under the sixth car during his inspection while the train was at the 59th Street station, so he did not descend to the track level during his inspection. At 4:38 p.m., approximately 75 feet south of the station, the sixth and seventh cars derailed to the east. As the train continued south, the two derailed cars moved away from the track structure, and at a point approximately 225 feet beyond the point of derailment, the sixth car struck a concrete and steel curtain wall, which is used to separate two tracks. The car was forced back toward the track structure, permitting the leading end of the seventh car to strike the end of the curtain wall. The side of the car was torn off. At 8:08 a.m. on January 15, 1979, the emergency train brakes applied on a 10-car subway train designated "A" while it was moving northbound at a point 300 feet south of Ralph Avenue. Inspection by the motorman revealed that the Nos. 3 and 4 wheels in the No. 1 truck of the fourth car had derailed. On February 14, 1979, at 7:23 p.m., a 10-car subway train designated "E" was southbound on the 53d Street line when the train's emergency brakes applied. An air leak was found between the seventh and eighth cars. The motorman had the air brakes isolated on these two cars; the train's brakes were then released and the train continued southward. About 120 feet into the Lexington Avenue station the train brakes again applied in emergency. The No. 1 truck on the seventh car had derailed. On March 21, 1979, a northbound eight-car subway train designated "CC" departed from Rockaway Park at 7:04 a.m. The motor man felt that his train was running slow and requested that a road car inspector meet the train. At the Euclid Avenue station a road car inspector boarded the train. The train speed seemed slow to him also. He had the motorman operate the controller on and off several times, and each time the train would pick up speed and then drop back to the slower rate. The road car inspector did not make any additional checks of the train's equipment; he said that the slow speed was caused by the the heavy load of people the train was carrying. He told the motorman that it was all right to proceed, and the road car inspector left the train. The train continued northward making regular station stops. As the train approached the 14th Street station at a speed estimated to be 20 to 25 mph, the motor man saw arcing accompanied by a loud noise, and he immediately stopped the train with the first four cars in the station. Both pairs of wheels of the No. 1 truck of the first car had derailed. Location of the Derailments The derailment of December 12, 1978, occurred at a crossover switch 120 feet south of the 59th Street station platform. The train was operating on the track designated as A1, which is the most westward track of six tracks which are numbered from west to east A1, B3, A3, A4, B2 and A2. (See figure 1.) There is also a series of crossovers that connect the six tracks. An opening in the curtain wall between tracks A3 and B3 is provided to permit the tracks to converge. Beyond the crossovers the curtain wall is used to separate tracks and to protect a line of columns that support 8th Avenue and 57th Street. The curtain wall was constructed of fabricated H-beams using 3-inch by 3-inch by 1/4-inch angle iron and 1/4-inch flat plate riveted together and secured to a concrete base at the bottom. Six-inch-thick concrete was used between the H-beams to form the wall. The derailment of January 15, 1979, occurred north of Rockaway Avenue on track A4, an express track. There are four tracks at this location numbered from east to west A2, A4, A3, and A1. The two outside tracks A2 and A1 are for local trains and tracks A4 and A3 are for express trains. The derailment of February 14, 1979, occurred in the 53d Street tube on track D3. There are two tracks at this location numbered east to west as D4 and D3. The derailed car traveled a distance of 1,300 feet before the train stopped. The derailment of March 21, 1979, occurred approximately 3,600 feet south of the 14th Street station on track A2. The train traveled 4,050 feet after it derailed, and came to a stop with the four north cars inside the 14th Street station, next to the island platform. There are four tracks at this location numbered from east to west A2, A4, A3, and A1. Tracks A2 and A4 are separated by an island platform, and tracks A3 and A1 are separated by an island platform. |