Large and In Charge - The Dennis "Big 6"

Dennis Bros. Pty. Ltd. was founded in 1895 with the company first entering the market producing bicycles. Six years later Dennis Bros. would continue to grow and branch out into the production of cars by 1901. It would not be for another seven years until Dennis Bros. would further develop the business and diversify into the production of fire engines. Their first fire engine would be produced in 1908, using a White and Poppe petrol engine and a Gwynne turbine pump. From then on they became one of the most dominant suppliers of fire appliances to the United Kingdom, the British Commonwealth and other worldwide markets for almost a century.

The early Dennis fire engines were identified by their engine power or pumping capacities, however, from the mid 1930’s, they used the relative size of the engine to identify specific models. The “Light 4” was the smallest in the range; followed by the “Light 6”, “Big 4”, and finally the “Big 6” as the largest.

Dennis Big 6 at Pyrmont Fire Station [Museum of Fire Collection]

Motor Engine (ME) 132 was the only “Big 6” of its kind ever purchased by the New South Wales Fire Brigades (NSWFB; now Fire and Rescue NSW, FRNSW). Although the Brigade began negotiations to purchase a second unit shortly after World War Two, Dennis advised that this model was to be superseded by a new Rolls-Royce eight-cylinder powered pumper, so the decision was made to wait for one of these chassis. Thus, ME 132 remained an orphan in the fleet, and in fact, Australia. The engine arrived at No. 1 Station Sydney Headquarters (now City of Sydney) in 1939, where the bodywork was designed and built by the Brigade, and was entered into service in April of 1940. Being designed by the Brigade allowed them to customise it to suit local conditions.

The “Big 6” is a Meadows designed 6-cylinder OHV (overhead valve) petrol engine of 9.5 litres capacity, developing about 120bhp. Drive is through a four-speed crash gearbox and worm-drive differential. Four-wheel servo assisted hydraulic brakes are fitted. The Dennis-Tamini centrifugal turbine pump fitted at the rear is rated at 800gpm (3600L/min), driven by a power-take-off on the gearbox.

Beginning service at No. 1 Station in 1940, the “Big 6” was used at all major fires, gaining further notoriety for the fact that it was always boarded by a Senior Officer, and/or higher ranks, up to and including the Deputy Chief Officer. During this time the engine became one of, if not the first, fire engines in NSW to be fitted with two-way radio communication. In 1951 the “Big 6” was transferred to No. 3 Station The Rocks. During its time here it was modified with the mudguards being shortened so as to prevent any damage being caused by contact to the kerb near the station. The “Big 6” was briefly returned to No. 1 Station in 1954 until it was again transferred to No. 38 Station Pyrmont later that same year where it served until 1967.

Dennis Big 6 in funeral procession, c. 1971 [Museum of Fire Collection]

In 1967, the Dennis “Big 6” was pensioned off to the Brigade’s Training College at Paddington, NSW, where it was used to train firefighter recruits in the use of pumps and hoses. The engine’s placement here also ensured that it was properly maintained during this time. On occasion it was even brought out for fire duties during some major fires in Sydney during this time and was also used as a coffin carrier during official Fire Brigade funeral processions. The appliance was modified for funerals with removable fittings that would ensure that the coffin was secure during processions, and that it would also be of use to the Training College and at major fires if need be.

Restoration of the Big 6 at Ted Pike's Workshop, May 2003 [Museum of Fire Collection]

The Dennis “Big 6” was withdrawn from service in August of 1973 as a result of a mechanical failure leading to the vehicle to be set aside for preservation purposes. The “Big 6” was eventually brought into the care of the Museum of Fire at Penrith in 1985. After some years in storage, an extensive restoration project began in 2002, with work undertaken by the passionate Museum volunteers, with the project being led by Ted Pike. The restoration work on the "Big 6" would not go unnoticed for its unique circumstances as a one-of-a-kind fire engine, pivotal to firefighting in Sydney, would achieve recognition on the NSW State Heritage Register in 2004. This hard work, along with the continual maintenance, is evidence of the significance of the appliance and the regard in which it is held.

The Dennis Big 6 on display at the Museum of Fire, June 2023

-Story by the Museum of Fire Heritage Team