In the early 1960s, the Department of Government Transport (DGT) bodied two buses, one Leyland Leopard and one AEC Reliance, at their workshops in Chullora with prototype light-weight designs. 

 

Aluminium framed, and making use of new materials such as fibreglass, the design featured airbag suspension, jet-air ventilation and vandal-proof moulded plastic seats, although the seats were soon replaced by more conventional vinyl ones. 

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3520, the Leyland prototype, was completed in August, 1964. It entered service with a Leyland 0.600 engine, and spent time at Burwood, Kingsgrove, Willougby and Brookvale Depots to enable staff and passengers to evaluate the design features. Staff soon named both the prototype buses 'Mr Whippy' after the similar looking ice cream vans.

 

It was later allocated to Burwood Depot, where it saw out the rest of its service. In 1980 the engine was replaced with a more powerful Leyland 0.680. The AEC prototype, 3521, was withdrawn and sold into private service in 1977.

 

3520 however, continued in passenger service from Burwood until 1982, when it was withdrawn and used as a staff bus at Chullora Workshops. It was the only 'old' bus to be painted in the Mercedes-Benz Mark II livery.

 

In 1986, the bus was placed on permanent loan to the Museum by the Urban Transit Authority (UTA). Restoration was complete in 1988 to original green and cream livery, and the vehicle was made to be fully operational. 

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Specifications: 

Engine: 11.6 litre six cylinder Leyland 0.680 diesel engine developing 150 B.H.P. at 2000 RPM.

Transmission: Four speed air operate pneumocyclic gearbox to a crown wheel and pinion differential.

 

Brakes: Air foot brake and a mechanical park brake.