Tasmanian Government 4-6-2 Locomotives in Australia

Class M (Locobase 8580)

Data from [], and [], all accessed 14 July 2007.

Pipe-festooned Pacific based on the Indian Government Railway's YB class that fulfilled all the requirements for this twisting, hilly narrow-gauge line. Like the Vulcan Foundry H-class 4-8-2s described on Locobase 8579, these Pacifics (works #7421-7430) had cast-steel SCOA-P drivers and roller bearings on every axle including the 4 under the tender, the main (connecting) rod, and the side (coupling) rods. Unlike the Hs, however, these engines had Belpaire fireboxes.

The Hobart-Launceston passenger service needed light but powerful engines, notes OS Nock (RWC VI, pl. 106), so this design used welded construction for such components as the inner steel liner to the Belpaire firebox, ashpan, and parts of the tender's tank. Line curvature is as tight as 330 ft radius, "and personal observation from the footplate has confirmed that they do ride these severe curves both smoothly and comfortably."

Four were rebuilt as MAs for freight work; see Locobase 2872.

Retirements came in the early 1960s, although M5 remained in service until 1971 as a suburban-traffic, special-service engine.

---

Class MA (Locobase 2872)

Data from [], and [], accessed 14 July 2007.

In 1957-58, four of the M-class Pacific engines were retrofitted with 48" drivers taken from Garratt locomotives and smaller pony-truck wheels. A change in weight distribution added a little more than 1 long ton to the adhesion weight. Tractive effort went up, but they were had a significantly lower factor of adhesion.

These were designated MA 1-4 and were the ex-M8, M1, M6, and M2, respectively. They tackled the more challenging North East line.