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
Specifications
Car body construction	Steel
Car length	A and C units: 45 ft 4 1⁄2 in (13.83 m) B units: 38 ft 11 3⁄4 in (11.88 m) Total: 137 ft 3 in (41.83 m)
Width	9 ft 10 15⁄16 in (3,021 mm)
Height	12 ft 1 3⁄4 in (3,702 mm)
Floor height	3 ft 1 1⁄8 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 1⁄2 in (1,435 mm)

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

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.