RAAF 210 Radar Station, Toorbul
- Radar/signal station
1295 Pumicestone Road, Toorbul 4510
RAAF 210 at Toorbul became operational in early 1944, and was one of five British-designed Advanced Chain Overseas (ACO) radar stations constructed in Queensland during World War II: four being completed (Benowa, Toorbul, Bones Knob and Charlie’s Hill) with a fifth not completed (Paluma). Two large concrete igloos are visible about 100m to the east of Volz Road, about half a kilometre south of Pumicestone Road.
The igloos, which are about 55m apart, measure about 10m long by 7m wide, Each has a large doorway at the west end, and a tower to the east. About 10m to the north of the northern igloo, and 10 metres to the south of the southern igloo, are the concrete footings for the timber receiving and transmitting towers, which were over 40m high. The footings are approximately 1.5 m x 1.5 m with remnant steel supports. There is a circular concrete feature within the northern tower footings, and there are several square concrete holes around the site.
Two smaller concrete igloos, orientated north-south and measuring about 5m long by 4m wide, are located about 15m into the trees west of Volz road. These contained the diesel-powered generators for the station. The southern generator igloo is level with a line about half way between the two large radar igloos.
In order to protect Brisbane from enemy aircraft the Royal Australian Air Force (RAAF) constructed RAAF 210 Radar Station at Toorbul, north of Brisbane, in late 1943. Its sister radar station, RAAF 209, was located south of Brisbane at Benowa, near Southport.
The delays that Australia experienced in acquiring British radar equipment spurred an innovative period of radar development by Australian scientists from late 1941. By the time the British Advanced Chain Overseas (ACO) radar system was installed at Toorbul, features of its design, especially its two conspicuous tall timber towers, had already been superseded by the Australian designed Light Weight Air Warning (LW/AW) radar.
One tower in ACO stations was for transmitting and the other was for receiving radar signals. The towers were spaced about 100 metres apart to ensure that radio pulses were received as echoes and not confused with transmissions. The towers did not rotate like those commonly used in other radar models. The ACO radar installation consisted of 14 switches on the receiver tower and more on the transmitter. These had to be constantly relayed from on to off, lower to higher, and between different directions. At Toorbul the two timber towers, which were assembled in kit form, were over 40m high.
The igloos, built of reinforced concrete with 300mm thick walls, were constructed to house the radar electronics and two tonne consoles for the transmitter and receiver. At Toorbul the northern igloo housed the receiving equipment whilst the southern igloo housed the transmitting equipment. The igloos could be covered with earth, and were designed with a small tower at one end which was equipped with a ladder and served as a ventilator and escape passage. However, the ACO igloos used in Australia were not buried. Entrance doorways at the other end were large enough to accommodate the radar consoles. Steel rods sticking out of the igloos were meant to secure camouflage netting, but were never used.
The ACO electronics were the second generation of the British CH (Chain Home) type of radar, a 'floodlit' system operating on the VHF band. The transmitter was a British MB3 model which put out 250 kW of power at 42.5 MHz. The transmitter aerial system was in two parts set at different heights to enable height finding using the floodlit system. Each part had four elements to cover four sectors of 120 degrees.
The receiver was a British RF7 (receiver fixed location) built in four vertical racks held in a frame of 2 x 2 x 0.6 metres. The receiver detected radio echoes from all directions simultaneously, and compared the strength of an echo from within a radius to identify the direction from which the signal was originating. The receiver had two parts on the tower plus crossed dipoles used for the height finding of an aircraft by comparing the echoes from the higher and lower sections on the tower.
It took several months to construct and calibrate an ACO radar system and the sheer size of the transmitter and receiver towers made them difficult to camouflage. The Toorbul Station was constructed by men from the Civil Constructional Corps (a division of the Allied Works Council). Specialist RAAF and British RAF personnel installed and calibrated electrical and radar equipment.
Nine British ACO radar stations were completed in Australia by the end of 1943 (while others were built but were never made operational). Four were completed in Queensland. As well as RAAF 210 at Toorbul, there was RAAF 209 at Benowa (since demolished); RAAF 211 at Charlie’s Hill; and RAAF 220 at Bones Knob, Tolga. An ACO station was started at Paluma, and concrete igloos were built that still exist on Lennox Crescent, but the towers were never built as the ACO program was cancelled in late 1943.
The Toorbul unit was formed at Sandgate on 20 September 1943 and moved to its radar site at Toorbul on 27 October 1943. RAAF 210’s towers and igloos were sited on flat cleared farmland adjacent to a swamp. The campsite was located west of Volz Road, across from the radar station amongst the trees.
The property owner was World War I serviceman Captain Uvedale Edward Parry-Okeden MC, MID, a Gallipoli veteran who greatly enjoyed the 'intrusion'. Servicemen, both Australian and later American, would be invited to the Parry-Okeden house for afternoon tea and sometimes dinner. Eggs were a rarity in a serviceman’s diet so Mrs “May” Parry-Okeden’s curried eggs were a particular favourite. Parry-Okeden’s house (Ningi) was about 190 metres south of the campsite, and its site is today marked by a large mango tree.
The radar equipment had arrived at the site on 7 October 1943 and on the 18th of that month the 1RIMU installation party arrived. By November 1943 Toorbul Radar Station No. 210 was still incomplete and heavy rain which rendered both camp and the radar station very boggy. In November 1943 it was planned to have 9 RAAF men and 22 Women’s Auxiliary Australian Air Force (WAAAF) women but this never came to pass, as WAAAF staffing was conditional on suitable accommodation being provided. Installation of equipment was complete by 15 January 1944 and the Station became operational at 1100 hours on 4 March 1944 with a staff of 1 officer and 31 other ranks (ORs).
ACO radar units were usually small, numbering around 35 personnel. The station was operated for 24-hours a day. Each shift comprised three-four people - one operator calling out the bearing and distance of the aircraft, one recording the plots, one working on the plotting table, and a fourth person to communicate by telephone to the local Fighter Sector (later Fighter Control Unit) headquarters. The average daily number of aircraft plots at Toorbul 210 Radar Station was 433 for the busy month of September 1944 with one heavy day reaching 540 plots.
RAAF 210 was off air from 4 to 11 February 1945 for maintenance. The unit’s strength had been reduced to 1 officer and 16 ORs by June 1945, and operations ceased on 31 August 1945 on a care and maintenance basis. The unit closed on 13 February 1946 and was disbanded on 21 February 1946. The timber towers were demolished that year.
Radar Station, Charlie’s Hill. Queensland Heritage Register 601716
WWII RAAF 220 Radar Station. Queensland Heritage Register 602741
Smith, N and Simmonds, E, (eds), 2007. Radar Yarns. Radar Returns, Hampton, Victoria.
National Archives of Australia, 231/9/1636 PART 1. Establishment, No 210 Radar Station, 1943-1945.
National Archives of Australia, 231/9/1636 PART 1 ATTACHMENT. Establishment, No 210 Radar Station, 1943-1945.
Walding, R. Defences of Moreton Bay—Toorbul Radar Station Unit 210RS
Dunn, P. Toorbul Radar Bunkers No 210 Radar Station RAAF
Australian War Memorial Photographic Collection.