the Turbotrain were very mechanically complex and the suspension arms were "telescopic arms which were in essence ball-bearing screw actuators; the suspension of the inside-bearing powered bogies was "especially complex" and attached to the turbines via "an intricate web of mechanical couplings and shafts". Production and use U.S. service Two Turbotrains (DOT1 and DOT2) were built at the Pullman Works in Chicago. High-speed testing of the trains was performed from a base at Fields Point in Providence, Rhode Island, using track between Route 128 near Boston and Westerly, Rhode Island (track segments along this section, to this day, are the only areas where Amtrak operates Acela revenue service at 150 mph). After its construction at the Pullman yards in Chicago, the Turbotrain was sent eastward on August 1, 1967, at regular speed and without passengers, to Providence, Rhode Island in order for UAC Aircraft Systems engineers to tear it down, study it for further development, and then eventual high-speed testing on the PRR's specially-rebuilt track between Trenton and New Brunswick, New Jersey. In a competition with a GE powered Metroliner on Penn Central's main-line between Trenton and New Brunswick, New Jersey on December 20, 1967, one of the TurboTrains reached . This remains the world speed record for gas turbine-powered rail vehicles. On January 1, 1968, the TurboTrain program was transferred from CSC to Sikorsky Aircraft Division (SA) of UAC. The United States Department of Transportation leased both trainsets and contracted with the New Haven Railroad to operate them. The New Haven had been in bankruptcy since July 2, 1961; on January 1, 1969, it was absorbed into the Penn Central Railroad, which inherited the contract. On April 8, 1969, Penn Central placed the equipment in service on the Northeast Corridor between Boston and New York City. The three-car sets carried 144 people and operated at a maximum speed of . The TurboTrains were equipped with third rail shoes for operation into Grand Central Terminal. In their first year of operation the trains' on-time performance approached 90 percent. They covered the in three hours and 39 minutes. After railroad bankruptcies and amid threats of more, the National Railroad Passenger Corporation (Amtrak) took over passenger service for most U.S. railroads, including the Penn Central, on May 1, 1971. Amtrak continued Turbotrain service between Boston and New York, switching to Pennsylvania Station as its New York terminal. It also briefly ran Turbotrains