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D-type Triplex (New York City Subway car)

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Title: D-type Triplex (New York City Subway car)  
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Subject: R32 (New York City Subway car), New York City Subway nomenclature, New York City Subway rolling stock, 1925 introductions, New York City Subway passenger equipment
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D-type Triplex (New York City Subway car)

D-type "Triplex"
A two-unit train of D-types approaching the Avenue H station on the BMT Brighton Line, October 23, 2004.
D-type interior
In service 1925–1965
Manufacturer Pressed Steel Car Company
Constructed 1925, 1927–1928
Number built 121
Number preserved 3
Number scrapped 118
Formation Three-section articulated units
Fleet numbers 6000–6120 A-B-C
Capacity 555: 160 (seated), 395 (standing)
Operator(s) Brooklyn–Manhattan Transit Corporation
New York City Transit Authority
Car body construction Steel
Car length A and C units: 45 ft 4 12 in (13.83 m)
B units: 38 ft 11 34 in (11.88 m)
Total: 137 ft 3 in (41.83 m)
Width 9 ft 10 1516 in (3,021 mm)
Height 12 ft 1 34 in (3,702 mm)
Floor height 3 ft 1 18 in (0.94 m)
Doors 12
Articulated sections 3
Maximum speed 45 mi (72 km) per hour
Weight 207,600–213,600 lb (94,166–96,887 kg)
Traction system Westinghouse 143 or GE PC-15 propulsion system, using GE 282D motors or Westinghouse 584 motors (200hp each). 4 motors per car (1 per truck).
Power output 200 hp (149 kW) per traction motor
Electric system(s) 600 V DC Third rail
Current collection method Top running Contact shoe
Coupling system WABCO H2A
Track gauge 4 ft 8 12 in (1,435 mm)

The D-Type,[1] commonly known as the Triplex, is a retired New York City Subway car with four units built as a prototype in 1925[2] and the production units built during 1927 and 1928.


  • History 1
  • Technical notes 2
    • Individual car notes 2.1
  • References 3
  • External links 4


The "D"s were purchased by the Brooklyn–Manhattan Transit Corporation specifically to augment the service provided by the BMT/BRT A/B Standards. They were used over the years in Southern Division lines based at Coney Island. This permitted several of the A/B units used in these services to be transferred to East New York, and in turn permitted the removal of the last BU wooden el cars from service in the BMT Nassau Street Line Other service improvements included the extension of various lines — the BMT Fourth Avenue Line one station from 86th Street to Bay Ridge – 95th Street and the BMT Canarsie Line from Montrose Avenue to a connection at East New York with the other lines operating out of that point. In addition, most stations along the Southern Division lines were being extended to permit operation of maximum length trains – 8 car "A/B"s or 4 unit "D"s.

They were originally placed in service on the Fourth Avenue Local running from 95th Street to Queensboro Plaza, with some additional units used on the Brighton Local. This was undoubtedly done to provide maximum exposure for these cars; however, in September 1928, before the entire fleet of 121 units had been delivered, the units serving in Fourth Avenue Local service were transferred to the Sea Beach Express, where, as heavyweight cars with a slow acceleration but very fast overall speed, it was felt that they could provide better service. In 1932, full length trains of these units began operating with only one conductor aside from the motorman.

The first major change of assignment for these cars came on April 27, 1950, when the units on the Brighton Local were transferred to Brighton Express service. The BMT Astoria Line's platforms were still under construction, and parts of the platforms were still closed to passengers, requiring trains to use two conductors when travelling on that line. As the A/B trains still used two conductors until September 1958, this move served to save on crews, although "D"s continued to be used on certain fixed intervals on the Brighton Local until December 1, 1955, and sporadically after that date.

On May 27–28, 1959, the Brighton Express now became virtually all D-Type (except once again for certain fixed intervals which used A/B's), with the Sea Beach Express for the first time in nearly 31 years seeing the usage of A/B-Types along with the D-Types that were still used. With the drastic reduction in West End service that took place at this time, it was decided to run all Sea Beach trains at maximum length 8 cars. The Brighton Express, in the meantime, continued to run a fluctuating 6 or 8 car service during the course of the day, which required much coupling and cutting of trains. As the D-Types were better suited for this purpose, having a much more advanced type of coupler, it was decided to keep these cars for that purpose on the Brighton Express, where they served virtually until the end of their lives.

A further change came over the days April 13–15, 1963, when the units used on the Sea Beach Express were transferred to the West End Express as well as the various Nassau Sreet. services as needed. As these cars were approaching their last days, and were now seen as oddball types, it was decided to cut their mileage as much as possible to simplify maintenance procedures; moveover, by June of that year, they began to reappear on the Sea Beach Express once again along with the above. This was undoubtedly to dissipate the mileage on them even further. The oft stated concern of their being too heavy for the Manhattan Bridge was apparently not a factor, as they could be seen in service on the Bridge to the very end of their lives.

Over their entire lifetime, they had appeared in all Southern Division services at one time or other, including all Nassau Street services, weekend Franklin Avenue Local service to Brighton Beach, Culver Shuttle, and also to Astoria and via the 60th Street Tunnel Connection and over the IND Queens Boulevard Line to Forest Hills (during the 1957 motorman's strike, some units ran over this line to 179th Street).

The units had a reputation with the BMT and subsequent operating agencies for being especially reliable, requiring minimal maintaining and experiencing fewer breakdowns than other New York subway equipment. The last units were retired from service on July 23, 1965, the last train in service having operated as a West End Local in the A.M. rush on that date..

Technical notes

The units had a reputation with the BMT and subsequent operating agencies for being especially reliable, requiring minimal maintaining and experiencing fewer breakdowns than other New York subway equipment. The last units were retired from service on July 23, 1965, the last train in service having operated as a West End Local in the A.M. rush on that date.. Among the innovations of the "D's" were the first New York rolling stock to include front destination signs with a route designation. These signs introduced the route numbering to the BMT system. The numbers started to be replaced in 1960 with the current letters on all subsequent equipment to be delivered. They also featured inside the cars a sign box which included large dual destination signs which could be keyed by the train operator to light up in the direction the train was traveling. There were also lighted signs to indicate whether a train was traveling via the Montague Street Tunnel or the Manhattan Bridge.

The D-type is articulated, consisting of three car body sections, sequentially labeled A, B and C, carried on four trucks.[3] All four trucks are powered by one 200 horsepower (150 kW) motor each. Two trucks are placed on kingpins near the ends of the A and C sections and don't have contact shoes. The other two trucks are placed beneath each of the articulation drums that attach the center B section to the A and C sections. These trucks have contact shoes. The wheel diameter varies with the type of axle: the motor axle wheels are 34 inches (860 mm) in diameter while the trailer axle wheels are just 31 inches (790 mm) in diameter. The D-types were the first articulated rapid transit rolling stock used in the United States.

After the D-types entered service, all subsequent rapid transit equipment ordered by the BMT, both production and experimental, were articulated units. Since the City of New York acquired the BMT in June 1940, no more articulated cars have ever been purchased for the New York City Subway.

Individual car notes

Brass window sashes were used on all units except for 6002 and 6003 which still had the older variety wooden sashes.

Car heating equipment was as follows: 1927 series – 6004-6038AB had P. Smith heaters and 6038C-6070 had Gold Car Heating Co. heaters. 1928 series – 6071–6095 had Gold Car Heating Co. heaters and 6096–6120 had P. Smith heaters.

D-type sets 6019, 6095, and 6112 were preserved and operated on various fan trips until 2004, when, in the 2004 "Parade of Trains," wheelslip heavily damaged the motors of one set. Unable to operate on its own power, the train was towed to Coney Island Yard. Set 6095 resided in the New York Transit Museum, while sets 6019 and 6112 were stored at Coney Island Yard and were transferred to Pitkin Yard when it was discovered that the cars had severe corrosion damage. However, recently, sets 6095 and 6112 received mechanical and cosmetic work at the 207th Street Yard and have been operational on fan trips since late June 2015.


  1. ^ Gene Sansome (2004). New York Subways: An Illustrated History of New York City's Transit Cars. The Johns Hopkins University Press.  
  2. ^ Cadahy, Brian (1995). Under the sidewalks of New York: the story of the greatest subway system in the world. Fordham University Press. p. 89.  
  3. ^ "BMT D-Type Triplex". Retrieved August 31, 2009. 

External links

  • The cab of D-type Triplex 6112
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