D-type Triplex (New York City Subway car)

A D-Type Triplex car on display at the New York Transit Museum

The inside of a D-Type Triplex car

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

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 Centre St. Subway. Other service improvements included the extension of various lines - the Fourth Ave. Line one station from 86th St. to 95th St. and the 14th St.-Canarsie Line from Montrose Ave. 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 Ave. Local running from 95th St. Brooklyn 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 Ave. 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 Astoria Line 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 (and continued to do so 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 here. 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 6/8 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 St. 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.

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

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.

Following the information as provided for the BMT Standards, the following may be noted:

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-6070had Gold Star Heating Co. heaters. 1928 series - 6071-6095 had Gold Star Heating Co. heaters and 6096-6120 had P. Smith heaters. (Information obtained from blueprints.) No information presently available on original 1925 units 6000-6003.

3 Sets of D-Types; Nos. 6019, 6095, and 6112, were preserved and operated on fan trips. During the "Parade of Trains" in 2004, wheelslip heavily damaged the motors of one set. Unable to operate on its own power, the train was towed to Coney Island Yard. 2 Sets were in storage in Coney Island Yard and have heavy rust and corrosion damage caused by salty air and require extensive mechanical and cosmetic work. These have now been transferred to Pitkin Yard where presumably they reside in an environment more protected from the elements than hitherto, until the proper rehabilitation work on these cars can get underway.. The 3rd Set resides in the New York Transit Museum and is in slightly better shape. It is hoped that the D-Types will be eventually returned to operational status.

Technical Notes

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 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 been ever been purchased for the New York City Subway.

D-Type Specifications

• Car Builder: Pressed Steel Car Company
• Car Body: steel
• Unit Numbers: 6000-6120 A-B-C
• Fleet: 121 three car articulated sets
• Car Length: 45 feet, 4½ inches - A and C, 38 feet, 11¾ inches - B (137 feet total)
• Car Width: 9 feet, 10 15/16 inches
• Car Height: 12 feet, 1¾ inches
• Track Gauge: Standard
• Propulsion System: GE PC-15 or WH 143
• Motors (one per truck): 4 x GE 282D or WH 584
• Power: 200 hp (150 kW) each
• Total Seating: - 50 - B , 55 - A and C
• Total Weight: 207,600-213,600 lb^[3]

Links

• The cab of D-type Triplex 6112

References

1. ^ Gene Sansome (2004). New York Subways: An Illustrated History of New York City's Transit Cars. The Johns Hopkins University Press. ISBN 0801879221. 
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. ISBN 0823216187. 
3. ^ ^{a b} "BMT D-Type Triplex". http://www.nycsubway.org/cars/bmt-d.html. Retrieved 2009-08-31.