M (New York City Subway service)
The M Queens Boulevard/Sixth Avenue Local is a rapid transit service in the B Division of the New York City Subway. Its route emblem, or "bullet", is colored orange since it uses the IND Sixth Avenue Line in Manhattan; the M operates at all times. Weekday service operates between 71st Avenue in Forest Hills and Metropolitan Avenue in Middle Village, via the IND Queens Boulevard Line and Sixth Avenue, the Williamsburg Bridge, the BMT Jamaica and Myrtle Avenue lines; this makes the M the only service that travels through the same borough via two different, unconnected lines. The M short turns at Essex Street in the Lower East Side of Manhattan on weekends, at Myrtle Avenue–Broadway in Brooklyn during nights; the M is the only non-shuttle service. Though the full route length between 71st Avenue and Metropolitan Avenue is about 18.2 miles, the stations are geographically located 2.47 miles apart, marking this as the shortest geographic distance between termini for any New York City Subway service, not a shuttle service.
An MJ service ran the entire BMT Myrtle Avenue Line until 1969, when the section west of Broadway in Brooklyn was demolished. Before 2010, the full-length M ran from Middle Village to southern Brooklyn via the BMT Nassau Street Line and Montague Street Tunnel; the M had run on the BMT Brighton Line to Coney Island–Stillwell Avenue until 1987. Afterward, it used the BMT Fourth Avenue Line, BMT West End Line in Brooklyn, terminating at Ninth Avenue or Bay Parkway. From July 2017 to April 2018, the full-length M terminated at Broadway Junction in Brooklyn, instead of Metropolitan Avenue due to construction on the Myrtle Avenue Line; until 1914, the only service on the Myrtle Avenue Line east of Grand Avenue was a local service between Park Row and Middle Village. The Myrtle Viaduct, a two-track ramp connecting the Myrtle Avenue Line with the BMT Broadway Elevated Line at the Myrtle Avenue–Broadway station was opened on July 29, 1914, allowing for a second service, the daytime Myrtle Avenue–Chambers Street Line.
These trains ran over the Williamsburg Bridge to Chambers Street station on the BMT Nassau Street Line in Lower Manhattan, ran over the express tracks on the Broadway Elevated during weekday and Saturday rush hours. The number 10 was assigned to the service in 1924. Sunday service was removed in June 1933. All Saturday trains began running local on June 28, 1952, on June 28, 1958, all Saturday and midday service was cut, leaving only weekday rush hour service, express in the peak direction. Marcy Avenue was a local stop, but beginning on February 23, 1960 all trains stopped there. M was assigned to the service in the early 1960s, with a single letter because it was an express service. Since the new cars using letter designations were not yet running on the Myrtle–Chambers service, it remained signed as 10; the line was designated "M" after the Chrystie Street changeover on November 27, 1967, but did not appear on the trains until the transition to rolling stock equipped with appropriate roll signs.
The second half of the Chrystie Street Connection opened on July 1, 1968, the JJ, which had run along Nassau Street to Broad Street, was relocated through the new connection to the IND Sixth Avenue Line. To augment QJ service to Broad Street, the M was extended two stations, from Chambers Street to Broad Street. Beginning Monday, October 6, 1969, to make up for the discontinuation of the MJ due to the closing of the Myrtle Avenue El south of Myrtle Avenue to Jay Street, the M was expanded to run middays and a new SS shuttle ran between Myrtle Avenue-Broadway and Metropolitan Avenue at other times. Effective January 2, 1973, the daytime QJ was truncated to Broad Street as the J, the M was extended beyond Broad Street during the day along the QJ's former route to Coney Island–Stillwell Avenue, via the Montague Street Tunnel and Brighton Line local tracks. By this time, the off-hour SS shuttle had been renamed as part of the M; the local K was eliminated on August 27, 1976, the M express service between Myrtle Avenue and Marcy Avenue ended in order to provide adequate service in Williamsburg, Brooklyn.
Reconstruction of the Brighton Line began on April 26, 1986, the weekday daytime M was shifted to the Fourth Avenue Line's express tracks south of DeKalb Avenue and the BMT West End Line terminating at Ninth Avenue during middays, with an extension to Bay Parkway during rush hours. This service duplicated a pattern that had last been operated as the TT until late 1967. M service along Fourth Avenue was switched to the local tracks on May 31, 1994, switching with the N, which had run local since the M was moved in 1987; the midday M was temporarily truncated to Chambers Street on April 30, 1995 from Ninth Avenue in Brooklyn due to the closure of the Manhattan Bridge during weekday middays for structural repairs. The change was made permanent on November 12, 1995, after the six-month repair project was completed. From April 1997 to August 1997, during late nights and weekends, the M terminated at Essex Street due to reconstruction of Myrtle Avenue. From May 1 to September 1, 1999, the Williamsburg Bridge subway tracks were closed for reconstruction, splitting M service in two sections.
One service ran at all times between Middle Village–Metropoli
G (New York City Subway service)
The G Brooklyn-Queens Crosstown is an 11.4-mile-long rapid transit service in the B Division of the New York City Subway. Its route emblem, or "bullet", is colored light green; the G operates at all times between Court Square in Long Island City and Church Avenue in Kensington, making local stops along its entire route. The G is the only non-shuttle service in the system. Since the 2000s, several improvements have been made to the G, including a route extension in Brooklyn and a full-route audit that identified solutions for issues on the G service; the G serves two stations in Queens: Court Square and 21st Street, which are both in Long Island City. Prior to 2010, it served all stations on the IND Queens Boulevard Line between Court Square and 71st Avenue in Forest Hills. In 1939 and 1940, the then-designated GG used the now-demolished IND World's Fair Line to access the 1939 New York World's Fair. From 1976 to 2009, the GG, which became the G, had its southern terminal at Smith–Ninth Streets.
The original Brooklyn–Queens Crosstown Local service began on August 19, 1933, as a shuttle between Queens Plaza on the IND Queens Boulevard Line and Nassau Avenue. This service was designated GG. Starting on April 24, 1937, GG trains were extended to Forest Hills–71st Avenue during rush hours, serving as the Queens Boulevard local while E trains ran express west of Continental Avenue; the entire IND Crosstown Line was completed on July 1, 1937, including the connection to the IND Culver Line. GG service ran at all times between Forest Hills -- 71st Church Avenue. Soon after, it was cut back to Smith–Ninth Streets; the 1939 World's Fair was served by GG trains. The trains ran via the short-lived IND World's Fair Line to Horace Harding Boulevard. Trains were extended to the World's Fair Station at all times during the fair, supplemented by PM hour E trains; the fair closed on October 28, 1940, was demolished that year. As a result, GG service was truncated to Forest Hills–71st Avenue. On July 1, 1968, service was again extended to Church Avenue during rush hours.
During these times, the F train operated as an express on the IND Culver Line. This service pattern ended on August 30, 1976, due to budget cuts and because of complaints from many customers at local stations on the IND Culver Line who wanted direct access to Manhattan. Afterwards the GG was cut back to Smith–Ninth Streets. On August 27, 1977, GG service was cut back to Queens Plaza during late nights, local service along Queens Boulevard was provided by the F. Effective May 6, 1985, use of double letters to indicate local service was discontinued, so the GG was relabeled G. On May 24, 1987, the N and R services switched terminals in Queens; as part of the reroute plan, Queens Plaza became the northern terminal for the G train on evenings and late nights. Three years on September 30, 1990, G service was extended to 179th Street during late nights to replace the F, which terminated at 21st Street–Queensbridge. Beginning on March 23, 1997, due to construction on the connector between the IND 63rd Street Line and the IND Queens Boulevard Line, G trains terminated at Court Square on evenings and weekends.
On August 30, 1997, late night service was permanently cut back from 179th Street to Court Square with the F running local east of Queens Plaza replacing G service, meaning that the G only ran along the Queens Boulevard Line on weekdays. On December 16, 2001, the 63rd Street Connector opened and Court Square became the northern terminal for the G train during weekdays, while G service was extended to Forest Hills–71st Avenue at all other times, which represented the reverse of the previous pattern. Service along the IND Queens Boulevard Line was replaced by the new V train during weekdays; the G was to be truncated to Court Square at all times to make room for the V, but due to rider opposition, it was cut back only on weekdays until 8:30 pm. On July 5, 2009, the G was once again extended south at all times to Church Avenue; this was required for overhaul of the Culver Viaduct, which caused the express tracks at Smith–Ninth Streets and Fourth Avenue/Ninth Street—used to switch G trains between tracks after they terminated at Smith–Ninth Streets—to be temporarily taken out of service.
This had several benefits. First, five stations served by only the F train had more frequent service. Additionally, riders from northern Brooklyn and Long Island City had a direct route to Kensington. Since the Church Avenue terminal had four tracks to store terminating G trains, as opposed to only one storage track at Smith–9th Streets, this reduced delays on both services because terminating G trains could switch to the storage tracks without having to wait in the station for another train to leave, as had occurred at Smith–Ninth Street. On July 19, 2012, MTA officials made this extension permanent because it provided more direct connections between Kensington and north Brooklyn. Due to the MTA's financial crisis in the late 2000s, as well as continued capacity issues on the IND Queens Boulevard Line, the G was to be cut back from Forest Hills–71st Avenue to Court Square at all times beginning June 27, 2010. However, due to planned track repairs during the times the G ran on the Queens Boulevard Line, it ceased running on that line on April 19.
In addition, train headways were reduced, which inconvenienced about 201,000 weekly commuters since they had to wait longer for G trains. Flood waters from Hurricane Sandy caused significant damage to the Greenpoint Tubes under the Newtown Creek. Although the G was back in service days after the hurricane, the tube needed permanent repairs. To al
Independent Subway System
The Independent Subway System known as the Independent City-Owned Subway System or the Independent City-Owned Rapid Transit Railroad, was a rapid transit rail system in New York City, now part of the New York City Subway. It was first constructed as the Eighth Avenue Line in Manhattan in 1932. One of three rail networks that became part of the modern New York City subway, the IND was intended to be owned and operated by the municipal government, in contrast to the operated or jointly funded Interborough Rapid Transit Company and Brooklyn–Manhattan Transit Corporation companies, it was merged with these two networks in 1940. The original IND service lines are B, C, D, E, F and G services. In addition, the BMT's M, N, Q and R now run on IND trackage; the Rockaway Park Shuttle supplements the A service. For operational purposes, the IND and BMT lines and services are referred to jointly as the B Division; until 1940, it was known as the Independent City-Owned Subway System, Independent Subway System, or Independent City-Owned Rapid Transit Railroad.
It became known as the IND after unification of the subway lines in 1940. The first IND line was the Eighth Avenue Line in Manhattan, opened on September 10, 1932; the original IND system was underground in the four boroughs that it served, with the exception of a short section of the IND Culver Line containing two stations spanning the Gowanus Canal in the Gowanus section of Brooklyn. In the early 1920s, Mayor John Hylan proposed a complex series of city-owned and operated rapid transit lines to compete with the BMT and IRT their elevated lines; the New York City Transit Commission was formed in 1921 to develop a plan to reduce overcrowding on the subways. The original plans included: Two major trunk lines in midtown Manhattan, with one running under Eighth Avenue and one under Sixth Avenue, which had an elevated line A crosstown subway under 53rd Street running under the East River to Queens Plaza, meeting with a Brooklyn–Queens crosstown line, continuing under Queens Boulevard and Hillside Avenue to 179th Street, where bus service would converge A subway under the Grand Concourse in the Bronx, diverging from the Eighth Avenue Line in Manhattan at 145th Street and Saint Nicholas AvenueThese lines were built as planned.
All but a short portion of the Culver Line are underground. On March 14, 1925, the groundbreaking of the Eighth Avenue subway took place at 123rd Street and St. Nicholas Avenue. On July 8, 1931, the first train of R1s left Coney Island at 11:35am and ran via the BMT Sea Beach Line to Times Square; the trip took 42 minutes. On September 10, 1932, the Eighth Avenue Line opened from 207th Street to Chambers Street, inaugurating the IND. In February 1933 the Cranberry Street Tunnel opened, along with the Eighth Avenue Line from Chambers Street to Jay Street–Borough Hall. On the northern end of the construction, in the Bronx, the connecting Concourse Line opened on July 1, 1933 from 205th Street to 145th Street. On the IND's opening day, it had a small subway car fleet of 300 cars, while the IRT had 2,281 subway and 1,694 elevated cars, the BMT had 2,472 cars; the new IND Eighth Avenue Line was built using 1,000,000 cubic yards of concrete and 150,000 short tons of steel. The roadbed of the new subway was expected to last 30 years.
At the time of the line's opening, other portions of the Independent Subway System were under construction, including five underwater tunnels: Cranberry Street Tunnel, 8,487 feet long Rutgers Street Tunnel, 5,479 feet long 53rd Street Tunnel, 5,589 feet long Concourse Tunnel, 5,397 feet long Greenpoint Tube, 4,790 feet longThere was some vandalism on the IND Eighth Avenue Line's opening day, as some of the uptown stations were broken into by people who clogged turnstile slots with gum and other objects. Two months after the IND opened for business, three exits from the 96th Street and 103rd Street stations – at 95th and 97th Streets and at 105th Street – were closed due to theft; the Queens Boulevard Line referred to as the Long Island City−Jamaica Line, Fifty-third Street−Jamaica Line, Queens Boulevard−Jamaica Line prior to opening, was of the original lines of the city-owned Independent Subway System, planned to stretch between the IND Eighth Avenue Line in Manhattan and 178th Street and Hillside Avenue in Jamaica, Queens.
The first section of the line, west from Roosevelt Avenue to 50th Street, opened on August 19, 1933. E trains ran local to Hudson Terminal in Manhattan, while the GG ran as a shuttle service between Queens Plaza and Nassau Avenue on the IND Crosstown Line, which opened on the same day; the Cranberry Street Tunnel, extending the Eighth Avenue express tracks east under Fulton Street to Jay Street–Borough Hall in Brooklyn, was opened for the morning rush hour on February 1, 1933. Until June 24, 1933, High Street was skipped; the first short section of the IND Culver Line opened on March 20, 1933, taking Eighth Avenue Express A trains south from Jay Street to Bergen Street. The rest of the line opened on October 7, 1933 to the "temporary" terminal at Church Avenue, three blocks away from the Culver elevated at Ditmas Avenue. In 1936, the A was rerouted to the IND Fulton Street Line and E trains from the Queens Boulevard Line replaced them. The
Minimum railway curve radius
The minimum railway curve radius is the shortest allowable design radius for the center line of railway tracks under a particular set of conditions. It has an important bearing on constructions costs and operating costs and, in combination with superelevation in the case of train tracks, determines the maximum safe speed of a curve. Minimum radius of curve is one parameter in the design of railway vehicles as well as trams. Monorails and guideways are subject to minimum radii; the first proper railway was the Liverpool and Manchester Railway, which opened in 1830. Like the tram roads that had preceded it over a hundred years, the L&M had gentle curves and gradients. Among other reasons for the gentle curves were the lack of strength of the track, which might have overturned if the curves were too sharp causing derailments. There was no signalling at this time, so drivers had to be able to see ahead to avoid collisions with other trains on the line; the gentler the curves, the longer the visibility.
The earliest rails were made in short lengths of wrought iron, which does not bend like steel rails introduced in the 1850s. Minimum curve radii for railroads are governed by the speed operated and by the mechanical ability of the rolling stock to adjust to the curvature. In North America, equipment for unlimited interchange between railroad companies are built to accommodate 288-foot radius, but 410-foot radius is used as a minimum, as some freight cars are handled by special agreement between railroads that cannot take the sharper curvature. For handling of long freight trains, a minimum 574-foot radius is preferred; the sharpest curves tend to be on the narrowest of narrow gauge railways, where everything is proportionately smaller. As the need for more powerful locomotives grew, the need for more driving wheels on a longer, fixed wheelbase grew too, but long wheel bases are unfriendly to sharp curves. Various types of articulated locomotives were devised to avoid having to operate multiple locomotives with multiple crews.
More recent diesel and electric locomotives do not have a wheelbase problem and can be operated in multiple with a single crew. The Tasmanian Government Railways K class was 610 mm gauge 99 ft radius curves Example Garratt 1,000 mm gauge 25 kg/m rails Main line radius - 175 m Siding radius - 84 m 0-4-0 GER Class 209 1,435 mm Not all couplers can handle sharp curves; this is true of the European buffer and chain couplers, where the buffers extend the profile of the railcar body. For a line with maximum speed 60 km/h, buffer-and-chain couplings increase the minimum radius to around 150 m; as narrow gauge railways and metros do not interchange with mainline railroads, instances of these types of railroad in Europe use bufferless central couplers and build to a tighter standard. A long heavy freight train those with wagons of mixed loading, may struggle on sharp curves, as the drawgear forces may pull intermediate wagons off the rails. Common solutions include: marshalling light and empty wagons at rear of train intermediate locomotives, including remotely controlled ones.
Easing curves reduced. More, shorter trains. Equalizing wagon loading better driver training driving controls, and c2013 Electronically Controlled Pneumatic brakes. A similar problem occurs with harsh changes in gradients; as a heavy train goes round a bend at speed, the reactive centrifugal force can cause negative effects: passengers and cargo may feel unpleasant forces, the inside and outside rails will wear unequally, insufficiently anchored track may move. To counter this, a cant is used. Ideally the train should be tilted such that resultant force acts straight "down" through the bottom of the train, so the wheels, track and passengers feel little or no sideways force; some trains are capable of tilting to enhance this effect for passenger comfort. Because freight and passenger trains tend to move at different speeds, a cant cannot be ideal for both types of rail traffic; the relationship between speed and tilt can be calculated mathematically. We start with the formula for a balancing centripetal force: θ is the angle by which the train is tilted due to the cant, r is the curve radius in meters, v is the speed in meters per second, g is the standard gravity equal to 9.80665 m/s²: tan θ = v 2 g r Rearranging for r gives: r = v 2 g tan θ Geometrically, tan θ can be expressed in terms of the track gauge G, the cant ha and cant deficiency hb, all in millimeters: tan θ ≈ sin θ = h a + h b G This approximation for tan θ gives: r = v 2 g h a + h b G
Brooklyn–Manhattan Transit Corporation
The Brooklyn–Manhattan Transit Corporation was an urban transit holding company, based in Brooklyn, New York City, United States, incorporated in 1923. The system was sold to the city in 1940. Today, together with the IND subway system, it forms the B Division of the modern New York City Subway; the original BMT routes form the J/Z, L, M, N, Q, R and W trains, as well as the Franklin Avenue Shuttle, with the IND B, D, F using BMT trackage in Brooklyn, as does a short section of the A in Queens. The M train enters the IND via the Chrystie Street Connection after crossing the Williamsburg Bridge, the Q, along with some rush-hour N trains enter the IND from the BMT 63rd Street Line and the R train enters the IND via the 60th Street Tunnel Connection; the Z train supplements the J in the peak direction during rush hours only. The Brooklyn–Manhattan Transit Corporation took over the assets of the Brooklyn Rapid Transit Company in 1923 following the previous company's bankruptcy. Like its predecessor it controlled subsidiaries which operated the great majority of the rapid transit and streetcar lines in Brooklyn with extensions into Queens and Manhattan.
One of these, New York Rapid Transit Corporation operated the elevated and subway lines. In 1923, their president, Gerhard Melvin Dahl, published a document called "Transit Truths" to explain the issues the company faced. In it he complained that the company had "met with the bitter and unfair opposition of Mayor Hylan." In a separate letter to Hylan he said: "For seven years, you have been misleading and fooling the people in this community… For seven years, you have blocked every effort at transit relief. You, only you, are to blame for the present…deplorable condition of the whole transit situation. You have used the transit situation as a political escalator". In the late 1930s, the BMT was pressed by the City administration of Mayor Fiorello H. La Guardia to sell its operations to the City, which wanted to have all subway and elevated lines municipally owned and operated; the City had two powerful incentives to coerce the sale: the BMT was forced by provisions of the Dual Contracts to charge no more than a five-cent fare, an amount set in 1913, before the inflation of World War I. the City had the right of “recapture” of those lines, built or improved with City participation under those Dual Contracts.
This meant that, if the City forced the issue, the BMT could have been left with a fragmented system and City competition in many of its market areas. The BMT sold all of its transit operations to the City on June 1, 1940. After World War II the city-built IND subway took over parts of the former BMT, starting in 1954 with the extension of the D train from its terminal at Church Avenue via a new connection with the former BMT Culver line at Ditmas Avenue. From 1954 the three remaining Culver stations between Ninth Avenue and Ditmas Avenue were used by the Culver Shuttle; the service was discontinued in 1975 because of budget cuts and was demolished. The 60th Street Tunnel Connection between the IND Queens Boulevard Line and BMT Broadway Line opened in December 1955; this new route was used by the BMT Brighton local, which ran to Astoria, for service to Forest Hills along with the IND GG local. The next year saw the new extension of the IND Fulton Street Line in Brooklyn connected to the rebuilt section of the former BMT Fulton Street elevated at 80th Street in Queens in April,1956.
The portion of the BMT Fulton Street El running west of 80th Street to Rockaway Avenue was demolished. The late 1950s and early 1960s saw the biggest project of that era with the building of the Chrystie Street Connection, the IND Sixth Ave express tracks; this project connected the IND Sixth Avenue services to the BMT services that ran over the Manhattan and Williamsburg Bridges. Express services were directly connected to the Manhattan Bridge, local services could use either the Williamsburg Bridge or the existing Rutgers Street Tunnel. Both connections opened in November 1967 and created the largest re-routing of train services in the history of the NYCTA; the BMT West End and Brighton Lines became served by IND services as a result. Between 1967 and 1976, some IND Sixth Avenue trains called KK and K, used the Chrystie Street Connection to the BMT Jamaica Line over the Williamsburg Bridge; that connection was discontinued due to budget cuts in 1976. In 1988, the BMT Archer Avenue Line was opened, connecting to what was the east end of the BMT Jamaica Line.
Two stations—Sutphin Boulevard–Archer Avenue–JFK Airport and Jamaica Center–Parsons/Archer—were added. In 1989, the BMT 63rd Street Line opened as an extension of the express tracks of the BMT Broadway Line, connecting to the IND 63rd Street Line at Lexington Avenue–63rd Street station. A connection from the Broadway/63rd Street Lines to the IND Second Avenue Line opened in 2017. In June 2010, as a result of more budget cuts, the Chrystie Street Connection was put back into revenue service use for M service; the BMT operated rapid transit through the New York Rapid Transit Corporation and surface transit through the Brooklyn and Queens Transit Corporation. The BMT was a national leader in the transit industry, was a proponent of advanced urban railways, participating in development of advanced streetcar designs, including the PCC car, whose design and advanced components influenced railcar design worldwide for decades; the company sought to extend the art of rapid transit car design with such innovations as articulated cars, lightweight equipment, advanced control systems, shared components with streetcar fleets.
Unlike the Interborough Rapid Transit Company, the other private operator of subways in New York City, the
J/Z (New York City Subway service)
The J Nassau Street Local and Z Nassau Street Express are two rapid transit services in the B Division of the New York City Subway. Their route emblems, or "bullets", are colored brown since they use the BMT Nassau Street Line in Lower Manhattan; the J operates at all times while the Z, operating internally as its rush-hour variant, runs with six trips in each peak direction on weekdays. When the Z operates, the two services form a skip-stop pair between Sutphin Boulevard–Archer Avenue–JFK Airport and Marcy Avenue. On weekdays during midday and rush hours, J/Z trains run express in each peak direction in Brooklyn between Myrtle Avenue and Marcy Avenue, bypassing three stations. At all other times, only the J operates; the current J/Z descends from several routes, including the JJ/15 between Lower Manhattan and 168th Street in Queens. The current skip-stop pattern was implemented in 1988; the Jamaica Line – known as the Broadway Elevated – was one of the original elevated lines in Brooklyn, completed in 1893 from Cypress Hills west to Broadway Ferry in Williamsburg.
It was a two-track line, with a single local service between the two ends, a second east of Gates Avenue, where the Lexington Avenue Elevated merged. This second service became the 12, was eliminated on October 13, 1950 with the abandonment of the Lexington Avenue Elevated; the second major service on the Broadway Elevated ran between Canarsie and Williamsburg via the BMT Canarsie Line, started on July 30, 1906, when the Broadway and Canarsie tracks were connected at East New York. As part of the Dual Contracts, an extension from Cypress Hills east to Jamaica was completed on July 3, 1918, a third track was added west of East New York, express trains began running on it in 1922; the Brooklyn–Manhattan Transit Corporation numbered its services in 1924, the Canarsie and Jamaica services became 14 and 15. Both ran express during rush hours in the peak direction west of East New York. Express trains would only stop at Myrtle Avenue, Essex Street and Canal Street, before making local stops afterwards.
Additional 14 trains, between Eastern Parkway or Atlantic Avenue on the Canarsie Line and Manhattan provided rush-hour local service on Broadway. When the 14th Street–Eastern Line and Canarsie Line were connected on July 14, 1928, the old Canarsie Line service was renamed the Broadway Line, providing only weekday local service over the Broadway Elevated west of Eastern Parkway; the Atlantic Avenue trips remained, rush-hour trains continued to serve Rockaway Parkway, though they did not use the Broadway express tracks. The 14 was cut back to only rush-hour service. On the Manhattan end, the first extension was made on September 16, 1908, when the Williamsburg Bridge subway tracks opened. Broadway and Canarsie trains were extended to the new Essex Street terminal, further to Chambers Street when the line was extended on August 4, 1913; when the BMT Nassau Street Line was completed on May 30, 1931, the 15 was extended to Broad Street, the 14 was truncated to Canal Street. Some 14 trains began terminating at Crescent Street on the Jamaica Line in 1956.
Manhattan–bound rush hour skip-stop service between Jamaica and East New York was implemented on June 18, 1959, with trains leaving 168th Street on weekdays between 7 AM and 8:30 AM. Express 15 trains served "A" stations, while the morning 14 became the Jamaica Local, running between Jamaica and Canal Street, stopped at stations marked "B". Express 15 trains continued to run express between Eastern Parkway and Canal Street, making only stops at Myrtle Avenue, Essex Street, Canal Street; these stations were as follows: All trains: 168th Street • Sutphin Boulevard • 75th Street–Elderts Lane • Eastern Parkway • Myrtle Avenue • Essex Street • Canal Street "A" stations: 168th Street • Sutphin Boulevard • 121st Street • 111th Street • Woodhaven Boulevard • 85th Street–Forest Parkway • Elderts Lane • Crescent Street • Cleveland Street • Eastern Parkway "B" stations: 168th Street • 160th Street • Sutphin Boulevard • Queens Boulevard • Metropolitan Avenue • 104th Street • Elderts Lane • Cypress Hills • Norwood Avenue • Van Siclen Avenue • Alabama Avenue • Eastern ParkwayLetters were assigned to most BMT services in the early 1960s.
The BMT Jamaica services retained their numbers until November 1967. The 15 became the QJ, the 14 became the JJ; when the Chrystie Street Connection opened on November 26, 1967, many services were changed. The two local services - the JJ and KK - were combined as the JJ, but without any major routing changes, thus non-rush hour JJ trains ran between Jamaica and Broad Street, while morning rush hour JJ trains ran to Canal Street, afternoon rush hour JJ trains ran between Canal Street and Atlantic Avenue or Crescent Street. The rush-hour express J was combined with the weekday QT Brighton Local via tunnel to form the weekday QJ, running between Jamaica and Brighton Beach via the Jamaica Line, BMT Nassau Street Line, Montague Street Tunnel, BMT Brighton Line; the RJ was a special peak-direction rush-hour service, running local on the Jamaica Line, Nassau Street Line, Montague Street Tunnel, BMT Fourth Avenue Line to 95th Street in Fort Hamilton. This was an extension of a former rush-hou
New York City Subway chaining
New York City Subway chaining is a method to specify locations along the New York City Subway lines. It measures distances from a fixed point, called chaining zero, following the twists and turns of the railroad line, so that the distance described is understood to be the "railroad distance," not the distance by the most direct route; the New York City Subway system differs from other railroad chaining systems in that it uses the engineer's chain of 100 feet rather than the surveyor's chain of 66 feet. Chaining zero, is a fixed point from which the chaining is measured on a particular chaining line. A chaining number of, for example, 243 at a specific line location identifies that the location is the length of 243 100-foot chains from chaining zero measured along the center line of the railroad. Once chaining is established, it is rare but not unheard of to change the location of chaining zero or the route along which it is measured on a given line. There are several examples of chaining numbers that refer to a chaining zero location that no longer exists or along a physical line that no longer exists, because of abandonment or demolition.
Notable among these are several existing chaining lines that originated near New York City Hall via the Brooklyn Bridge, discontinued since 1944. It is possible for a reroute to alter the accuracy of chaining numbers slightly. Exceptions exist to the principle that chaining numbers represent a railroad distance to the zero point. On the original IND chaining zero for the original system is a political rather than physical location, there is no railroad at or near the zero point. Sometimes trackage is chained backwards from a tie point with another line; the three divisions each had one separate Mileage zero before the 1958 opening of the Far Rockaway–Mott Avenue station. The zeros were changed after the Far Rockaway station's opening, are now at the railroad southernmost points of each division; the IND division-wide zero is at the Far Rockaway station's bumper blocks, the IRT zero is a northbound home signal at the north end of New Lots Avenue station, the BMT zero is in the center of Coney Island–Stillwell Avenue station.
Since the IRT Flushing Line is operationally separate from the rest of the system, it uses a different zero from the rest of the IRT. The IRT Flushing Line's Mileage zero is at 34th Street–Hudson Yards, before the 7 Subway Extension opened in 2015, the zero was at Times Square. Chaining lines are routes on physical railroad lines that are described by one or two letters for the purpose of identifying locations on those lines. Chaining lines are not the same as the physical lines they run on. One physical line may have several chaining letters, one chaining line may cover several physical lines; the letters assigned to a chaining line have nothing to do with the letters displayed on trains and public maps and timetables. These latter are subway service letters. See: New York City Subway nomenclature and List of New York City Subway services. For example, the BMT A chaining line begins at BMT South chaining zero north of 57th Street–Seventh Avenue on the BMT Broadway Line, but is interrupted north of the Canal Street stations, where the express tracks becomes BMT H for the trip over the Manhattan Bridge south side tracks and the local tracks become BMT B for Lower Manhattan and the Montague Street Tunnel.
The BMT A line begins again in the middle of the Manhattan Bridge span on the north side tracks, passes through DeKalb Avenue and becomes the BMT Brighton Line for that line's entire distance to Stillwell Avenue. BMT A traversed the entire north side of the bridge, connecting Canal to DeKalb, while H ran towards Chambers St. instead of Canal, but this was reconfigured as part of the Chrystie Street Connection. The IND B designation was extended past the portal of the new connection, to meet the BMT A in the middle, yet retained the BMT chaining numbers on the bridge itself; the tracks leading to Chambers St. were severed from the bridge and were re-designated as part of BMT J. In a few cases, the chaining lines and service letters are coincident, such as the IND A chaining line following the A service from 207th Street to Euclid Avenue, while the IND C was the IND Concourse Line, served by the C service. However, that service was moved off of the Concourse line, while the chaining code remains.
Each specific location along a line is known as a chaining station, is identified by a number unique to that chaining line. The precision of the location depends on its usage. On engineering maps, the location of such features as curves, crossings and platforms are ordinarily specified to a precision of 1 foot; this is expressed as. For greater precision, or where style or protocol requires it, unit of less than a foot may be described; the Brooklyn Rapid Transit Company used without trailing zeros: thus a map location designated as P. S. 14+70.25 would indicate that the Point of a Switch at that location is 1,470 and one quarter feet from chaining zero. Signals are identified by the chaining line and track number, by the nearest 100-foot chaining station. In this usage only the number of 100-foot chains from chaining zero are displayed. Thus, a signal on the BMT with a designation of A2 / 102 would be on the BMT chaining line A, track 2, within 50 feet of the chaining station at 10,200 feet from chaining zero.
Each track on a chaining line is give