British Rail Class 483

British Rail Class 483
Island Line Class 483 No. 008 at Shanklin
The refurbished interior of an Island Line Class 483
In service	1938-1989 on London Underground 1989-present on Island Line
Manufacturer	Metro Cammell
Family name	Tube stock
Formation	2 cars per trainset
Capacity	84 seats (2 car set)
Operator(s)	Island Line Trains
Depot(s)	Ryde depot
Specifications
Maximum speed	45 mph (72 km/h)
Weight	55 t (54 long tons; 61 short tons) each 2 car set.
Power output	500 kW (670 hp) total power per 2 car set.
Electric system(s)	630 V DC 3rd rail
Current collection method	Contact shoe
Track gauge	4 ft 8 1⁄2 in (1,435 mm) standard gauge

The British Rail Class 483 electrical multiple units were originally built as units for London Underground. They were extensively refurbished between 1989 and 1992 by Eastleigh Works, for use on services on the Isle of Wight's Island Line. This was despite having already worked for nearly 50 years on the London Underground. The units replaced the even older and life-expired Class 485 and Class 486 units, which were introduced in 1967, but were originally built as units for the London Electric Railway in 1923. The stock is around 80 years old, making it the oldest type in Great Britain to remain in regular service and South West Trains currently has no plans to replace them.

The trains were originally built by Metro-Cammell as 1938 tube stock for London Underground. An initial batch was withdrawn from service in 1973, and they were considered for use on the Island Line (which would not bear that name for another 16 years). However, the under-floor equipment was thought to be a problem, as extensive adaptations would be needed to Ryde Works to allow fitters to access it. It was also felt that the under-floor equipment would be vulnerable to salt water damage on Ryde Pier, especially in bad weather.

The last batch of 1938 stock was withdrawn in 1985, except for five trains required on the Northern line between 1986 and May 1988 due to increasing passenger numbers. In 1987 Network SouthEast managers realised that the existing 1923-built Class 485 trains would not be economically serviceable beyond around 1990 and thoughts turned to the future of the line. After closure of the route was discounted, it was decided to purchase and refurbish 1938 stock.