M2/M4/M6 (railcar)

M2/M4/M6
An MTA-owned Budd M2 car at New Haven-Union Station in August 2006.
In service	M2: April 1973-December 2018 M4: late 1987-2015 M6: 1994-2015
Manufacturer	Budd Company/General Electric/Canadian Vickers/Avco (M2) Tokyu Car (M4) Morrison-Knudsen (M6)
Built at	Erie, Pennsylvania (GE Shops)
Family name	Budd Metropolitan
Replaced	Kawasaki Heavy Industries M Series rail car
Constructed	M2: 1973-1976[1] M4: 1987[1] M6: 1993-1995
Entered service	M2: April 1973 M4: late 1987 M6: 1994
Scrapped	2012-2018
Number built	M2: 244 M4: 54 M6: 48
Number preserved	M2: 2 M6: 4 (training only)
Number scrapped	M2: 242 M4: 54 M6: 44
Formation	M2: Married pair M4/M6: Triplet
Fleet numbers	M2: 8400-8471, 8500-8571, 8650-8669, 8700-8747, 8800-8851[1] M4: 8900-8935, 8950-8985[1] M6: 9000-9031, 9050-9081
Capacity	Seated passengers: M2: 120 (A car); 114 (B car)[1] M4: 118 (A car); 113 (B car); 120 (D car)[1] M6: 118 (A car); 106 (B car)[2]
Operators	Penn Central Conrail Metro-North Railroad
Lines served	New Haven Line
Specifications
Car body construction	Stainless steel[1]
Train length	170 ft (51.82 m) - 1,020 ft (310.90 m)
Car length	85 ft 1+1⁄2 in (25,946 mm)[1]
Width	10 ft 8 in (3,250 mm) (max)
Height	13 ft (3,962 mm) (rail to roof) 14 ft 9 in (4,500 mm) (rail to top of resistor grid shrouding)
Floor height	4 ft 3+1⁄16 in (1,297 mm)
Platform height	4 ft (1,219 mm)
Doors	Quarter point, double leaf automatic
Maximum speed	100 mph (161 km/h) (design) 80 mph (129 km/h) (service)
Weight	M2: 112,000 lb (50,802 kg)[1] M4: 133,000 lb (60,328 kg) (A car) 128,000 lb (58,060 kg) 132,000 lb (59,874 kg) (D car) (B car)[1]
Axle load	35,600 lb (16,148 kg)
Traction system	Transformed AC overhead line current fed through mercury arc Ignitron (M2-original) rectifiers to a camshaft resistance motor controller Transformed AC overhead line current fed through Silicon (M2-rebuilt/M4/M6) rectifiers to a camshaft resistance motor controller DC third rail current fed directly to resistance controller
Traction motors	M2: 4x 160 hp (119 kW) GE 1259A DC motors[1] M4: 4x 162 hp (121 kW) GE 1259 DC motors[1]
Power output	M2: 640 hp (477 kW)[1] @ 25 mph (40 km/h) M4: 648 hp (483 kW)[1] @ 25 mph (40 km/h)
Tractive effort	10,000 lbf (44.48 kN) @ 0 mph (0 km/h) 14,200 lbf (63.16 kN) @ 10 mph (16 km/h) 5,565 lbf (24.75 kN) @ 50 mph (80 km/h) 3,878 lbf (17.25 kN) @ 80 mph (129 km/h) 1,900 lbf (8.45 kN) @ 100 mph (161 km/h)[3]
Acceleration	1.5 mph/s (2.4 km/(h⋅s)) - 2 mph/s (3.2 km/(h⋅s)) (Starting)
Deceleration	3.2 mph/s (5.1 km/(h⋅s)) (Emergency)
HVAC	electric heat, air conditioning
Electric system(s)	Third rail: 750 V DC Overhead catenary: 11–13.5 kV 25/60 Hz AC
Current collector(s)	Third rail: Contact shoe Overhead catenary: Pantograph
UIC classification	Bo′Bo′+Bo′Bo′
AAR wheel arrangement	B-B+B-B
Bogies	GSI 70
Braking system(s)	Pneumatic, dynamic
Safety system(s)	ATC and Pulse code cab signaling
Coupling system	WABCO Model N-2A[1]
Multiple working	Yes
Track gauge	4 ft 8+1⁄2 in (1,435 mm) standard gauge

The M2, M4 and M6 were three similar series of electric multiple unit rail cars produced by the Budd Company (M2), Tokyu Car Corporation (M4), and Morrison-Knudsen (M6) for the Metropolitan Transportation Authority (MTA) and the Connecticut Department of Transportation (ConnDOT). Initially branded as the Cosmopolitans, the cars were later more popularly known under their model names. They ran on the New Haven Line (then part of Penn Central, now a part of Metro-North) for most of their service life.

The M4s and M6s were retired by Metro-North in 2015, followed by the last M2s in 2018. They have been largely replaced by new M8 railcars. One pair of M2s has been preserved at the Danbury Railway Museum in Connecticut.