Tasmanian Government Railways Y class

Tasmanian Government Railways Y class

Preserved Y3 at the Queen Victoria Museum and Art Gallery, Launceston in June 2013

Type and origin Power type Diesel-electric Builder Tasmanian Government Railways Inveresk Build date 1961-1971 Total produced 8

Specifications UIC class Bo-Bo Gauge 1,067 mm (3 ft 6 in) Wheel diameter 3 ft 0 1⁄2 in (0.927 m) Wheelbase 23 ft 10 in (7.264 m) Length 44 ft 9 in (13.640 m) Height 12 ft 2 1⁄2 in (3.721 m) Axle load 14.5 tons Loco weight 58 tons Fuel type Diesel Prime mover English Electric 6SRKT Mk II (Y1-Y6) English Electric 6SRKT Mk III (Y7-Y8) Cylinders Inline 6 Cylinder size 10 in × 12 in (254 mm × 305 mm) Train brakes Vacuum (Y1 & Y5 later converted to air)

Performance figures Maximum speed 45 miles per hour (72 km/h) Power output 800 hp (600 kW) Tractive effort 34,000 lbf (151.2 kN)

Career Operators Tasmanian Government Railways Number in class 8 Numbers Y1-Y8 First run 1961 Current owner TasRail Disposition 2 in service, 5 preserved, 1 converted to driving van

The Y class was a class of diesel locomotives built by the Tasmanian Government Railways between 1961 and 1971.

The Y class were designed by English Electric and constructed by the Tasmanian Government Railways' Inveresk Workshops. Eight were built as mainline freight and passenger locomotives between 1961 and 1971.

Following the success of the X class, the Tasmanian Government Railways decided to order additional diesel locomotives.

English Electric submitted plans that were quite similar to the South Australian Railways 800 class and Midland Railways of Western Australia F class. They were slightly larger and more powerful than the X class. They had a similar layout to the X class, a long hood unit with the cab at one end.

Construction began at the TGR's Inveresk Workshops in 1961, and three of the planned eight were completed relatively quickly. However, construction of the other five was slow, with the last not being delivered until 1971, by which time the design had become dated.

The Y class were fitted with an English Electric 6SRKT Mark II (Mark III on last two) in-line six turbocharged diesel engine. They have a Bo-Bo wheel arrangement and end-platforms, making them visually different from the X class.

In line with standard TGR practice of the time, they were fitted with hook-and-link couplers and vacuum train brakes (air on locomotive). With a light tractive weight of only 58 tonnes, a reasonably powerful engine of 825 horsepower (615 kW) and a fairly basic bogie design, gaining traction on long uphill grades was found to be difficult. They were noted to have a tendency to wheel-slip badly. Nevertheless, they were considered successful.