In Active Service – Maritime

Number 11 Squadron was formed at Port Moresby in New Guinea in September 1939 operating Short Empire flying boats. In 1942 the squadron began operating from Cairns with Catalina aircraft. Disbanded after the war in 1946, 11 Squadron was reformed in 1948 at Rathmines, NSW, only to be again disbanded in 1950. Later that year 11 Squadron was again reformed at Pearce, Western Australia, with Lincoln aircraft which were replaced with Neptunes in early 1951. In 1968, 11 Squadron took delivery of 10 P-3B Orions and began operations at Edinburgh.

Number 492 Maintenance Squadron was formed in mid-1977 to provide maintenance support to both 1 0 and 11 Squadrons. The Maritime Analysis and Training Squadrons (MATS) was formed from the training flights of both 10 and 11

Squadrons on January 1, 1977, and is responsible for conversion training of all aircrew to the Orion aircraft. MATS is also responsible for the detailed analysis of inflight records, particularly acoustic records, and the investigation and formulation of new tactics.

Lockheed P-3 Orion

The Lockheed Orion was originally based on the successful Electra civil passenger airliner which first entered commercial service in 1959. Worldwide, 157 P-3A and 145 P-3B Orions have been manufactured, and the latest P-3C version is in current production. The RAAF Orions are powered by tour Allison T-56 turboprops, one or two of which are usually shut down on patrol to conserve fuel, enabling it to stay on patrol for up to 1 7 hours covering a quarter of a million square miles of ocean. It can fly at speeds greater than 400 knots, but usually patrols at around 200 knots.

From Edinburgh, the Orion is capable of reaching any point in Australia within tour hours. The secret of the Orion’s success, however, is not due so much to its aerodynamic performance but its advanced electronic equipment. For example, the P-3C carries a digital computer with a 458,000 word memory. The P-3B carries less sophisticated equipment than the “C” model but is still an extremely potent sub-hunter. The RAAF P-3Cs are now being fitted with the Australian designed Barra sonobuoy [built by Amalgamated Wireless A/Asia (AWA) and Commonwealth Aircraft Corporation] and its Marconi-Elliott AQS-901 sonics processor. The “B” version will shortly be updated with new electronics to increase its effectiveness.

Internally the Orion is filled with a mass of pushbutton navigational and electronic equipment, and the flight deck is spacious and well-equipped. The P-3 is pressurised and air-conditioned, and has, of course, a comprehensive galley and toilet. The Orion normally carries a crew of 11 consisting of two pilots, two flight engineers, and depending on task, up to eight navigators and air electronics officers (AEOs). The navigators are responsible for guiding and tracking the aircraft over its patrol pattern, while the AEOs maintain a vigilant watch for shipping or submarines, and would also be responsible for locating enemy vessels in the event of war. One of the navigators acts as a tactical coordinator (TACCO) who, as the name suggests, coordinates the efforts of individual crew members to follow one prescribed tactic. All shipping spotted by the Orions is photographed and identified, and information gathered may be passed on to other government departments such as Customs and Immigration. On average, 14 search and rescue missions are carried out each year, and at least one Orion crew is required to be on standby around the clock each year.

Equipment

The most striking feature of the Orion, and indeed most anti-submarine aircraft, is the long tail boom, which is a magnetic anomaly detector (MAD) boom, a device that aims to pinpoint a submarine, after it has been localised by sonobuoys, by detecting the effect of the submarine on the magnetic field of the earth. Radar is another detection medium, and the Orion is equipped with a search radar system and Doppler.

The search radar has a 200nm range. Another system of detection, and the most effective, is the sonobuoy of which there are two groups: active and passive. Passive sonobuoys are basically buoys that receive acoustic signals through a hydrophone from a target submarine and transmit the data back to the aircraft. The acoustic data is then interpreted through a sonics processor which sorts out the information to give a bearing as a visual display and aura signal to the operator. By dropping a number of buoys and using triangulation, the position of the submarine can be accurately pinpointed. Active, sonobuoys actually transmit in the water to receive a reflected signal from the target submarine and transmit the information back to the aircraft. However, active sonar has the disadvantage of giving away the presence of the search aircraft (passive sonar can not be detected), but has the advantage of giving both bearing and range. The P-38 is equipped with Julie and Jezebel sonobuoys and the P-3C has Jezebel and Barra, but up to 84 buoys of various types can be carried. Omega navigation system is also carried.

The Orion’s offensive weapons include conventional high explosive bombs, torpedoes, and mines, which are carried in the weapons bay and on underwing hardpoints. The P-38 has a 70 million candle power searchlight for identifying ships at night, but the P-3C has the added advantage of carrying an infrared detection device that presents a clear picture of the ship on a TV screen. Flares are also carried.

On return to base, the aircraft pass through the “birdbath”, a giant shower that washes the sea salt from the Orion to retard corrosion.

The 92 Wing Orions, flying their long and lonely patrols, provide an invaluable detection system. and anti-submarine facility vital for Australia’s continued security – the guardians of our sea lanes.