81-720/721

81-720/721
In service10 June 1998-2 August 2019
ManufacturerMetrovagonmash
Built atMetrovagonmash
Family name81-720 series
Replaced81-717 series
Constructed1991-2004
Entered service1998
Refurbished2013
Scrapped2018–2019
Number built91 (cars)
Number in serviceNot in use
Predecessor81-717 series
Successor81-740 series
Formation2 to 8 cars
Capacity330/350 passengers
OperatorMoskovsky Metropoliten
Specifications
Car body constructionAluminium
Train length155 meters (in 8 wagons version)
Car length20 m (65 ft 7+38 in)/19.21 m (63 ft 14 in)
Width2.7 m (8 ft 10+14 in)
Height3.644 m (11 ft 11+12 in)
Doors8
Maximum speed100 km/h (62 mph)
Weight34.5 t (34.0 long tons; 38.0 short tons)/33 t (32 long tons; 36 short tons)
Power output660 kW (890 hp)
Acceleration1.3 m/s2 (4.3 ft/s2)
Deceleration1.3 m/s2 (4.3 ft/s2)
Safety systemsSKIF (СКИФ), ALS-ARS (АЛС-АРС)
Track gauge1,520 mm (4 ft 11+2732 in) Russian gauge

81-720/721 (Yauza, alternatively spelled as Jauza, Russian: Яуза), is a subway car model used by the Moscow Metro. The origins of the design go back to 1987, and the first train was built in 1990–1991. Production of "Yauza" was discontinued in 2002 due to ongoing reliability issues. Now «Yauza» is not in use cause of many problems with braking and ALS-ARS systems (Automatic Train Signalization with Automatic Speed Control)