British Rail Class 421
| British Rail Class 421 (4-CIG) | |
|---|---|
 Class 421/7 no. 1498 at North Weald in 2012 | |
 The interior of a standard class carriage | |
| In service | 1964-2005 (Main line) 1964-2010 (Lymington branch) |
| Manufacturers | Holgate Road carriage works, York |
| Number built | 166 |
| Formation | Driving trailer + Motor coach + Trailer/Buffet + Driving trailer |
| Design code | 4-CIG |
| Operators | |
| Specifications | |
| Train length | 265 feet 8+1⁄2 inches (80.988 m) |
| Width | 9 feet 3 inches (2.82 m) |
| Height | 12 ft 9+1⁄4 in (3.893 m) |
| Maximum speed | 90 mph (145 km/h) |
| Weight | 150 long tons (152 tonnes; 168 short tons) |
| Traction motors | Four |
| Power output | 4x 250 hp (190 kW) Total: 1,000 hp (750 kW) |
| Electric systems | 750 V DC third rail |
| Current collection | Contact shoe |
| Coupling system | Drop-head buckeye |
| Track gauge | 4 ft 8+1⁄2 in (1,435 mm) standard gauge |
The British Rail Class 421 (4-CIG) electric multiple units were built at BR's Holgate Road carriage works in York, England, between 1964 and 1972. These were built in two batches and were initially introduced on services on the Brighton Main Line; later, they were introduced on services to Portsmouth. They replaced older Southern Railway-designed trains, such as the 5-BEL Brighton Belle and 4-COR. The fleet's lifespan was 46 years.