Country of origin:

United States of America

Description:

Long-range maritime patrol aircraft

Power Plant:

Four 3,663 kw (4,910 eshp) Allison T56-A-14 turboprops

Specifications:

Armament:

Two Mk 101 nuclear depth bombs and four Mk 43, 44 or 46 torpedoes; or eight Mk 54 bombs. All ten external pylons could carry torpedoes, mines or rockets. Max external stores load 6,220 kg (13,713 lb)

History:

Developed as a successor to the Lockheed P2V Neptune maritime patrol bomber from the Lockheed L-188 Electra commercial transport, the prototype YP3V-1 Orion (serial 148276), which had a fuselage 2.1 m (7 ft) shorter than the commercial aircraft, was flown for the first time on 25 November 1959. After an intensive development programme, it was named Orion (the ancient God of the Hunt), and entered production with deliveries to the US Armed Services beginning in 1961, an order for 157 examples, known as the P-3A, being placed initially on 25 October 1960. The Orion airframe was strengthened to absorb the repeated gust loads experienced in low-level flying over the open sea, and was stressed to 3G. Special attention was paid to prevent corrosion which is prevalent in the atmosphere where the aircraft was to operate. In 1965 production was transferred to the P-3B. This was fitted with more advanced detection equipment. Production of the P-3B totalled 145 aircraft.

In 1960 a programme was launched to develop a new integrated ASW avionics installation for the new model, the P-3C, a P-3B being converted as the prototype for this model, which first flew on 18 September 1968. This model had enhanced capability to deal with acoustic, radar, electronic surveillance etc. Management of weapons and stores was performed largely by a computer.

The Orion was chosen for the RAAFs No 11 Squadron as it could rapidly deploy to any part of the Australian coastline on maritime patrol duties, the Allison engines giving both a fast transit speed and a long range. It was able to perform the anti-submarine warfare and search and rescue roles, as well as coastal surveillance. Five P-3B-95-LOs (A9-291 to A9-296 – c/ns 5401 to 5405) and four P-3B-100-LOs (A9-297 to A9-300 – c/ns 5406 to 5410) were supplied to the RAAF and five P-3Bs to the RNZAF (NZ4201 to NZ4205).

The aircraft for the RAAF replaced Lockheed P2V-5 Neptunes with No 11 Squadron, which up to then had operated from Richmond, NSW the squadron then with the new equipment being transferred to Edinburgh, SA. One (A9-296) was lost in an accident at Moffett Field, California during acceptance trials in the USA on 11 April 1968, and a further aircraft, a P-3B-105-LO (A9-605 – c/n 5286), was obtained as a replacement. This aircraft, after retirement, was flown to the US where it was converted to Airborne Early Warning and Control Aircraft [AEW & C] configuration as N96LW, later becoming N146CS with the US Custom Service. One P-3B (A9-299) became N91LC and became the prototype for the Airborne Early Warning & Control Aircraft. Six (A9-292 to A9-295, and A9-297 and A9-298) went to the Portuguese Air Force, and one (A9-291) went to the RNZAF as NZ4206 (c/n 5401) in April 1985.

A9-292 also went to Burbank, California after retirement and became the prototype of the P-3P variant, being registered N4003X, later going to the Portuguese Air Force, with other ex-RAAF aircraft [noted above], as serial 4801. In January 1984 A9-300 was written-off after serious damage by fire at Edinburgh. The fuselage was used as an advanced avionics systems mock-up simulator. The first three aircraft of this batch arrived at Edinburgh on 11 May 1968.

The New Zealand aircraft were attached to No 5 Squadron at Whenuapai. In June 1980 a contract was let with Boeing Aerospace for the upgrading of the RNZAF P-3B aircraft by fitting new data-handling and display systems, radar, infra-red detection sensors and Omega and inertial navigation equipment. The first aircraft was completed in September 1983 and the programme concluded in 1985. At this stage these aircraft became known as the P-3K Orion. In May 1995 a contract was let to manufacture new wings and horizontal stabilisers for the RNZAF P-3K aircraft, this being expected to allow the aircraft to operate until 2015. However, a further upgrade in 2001 was cancelled by the New Zealand Government.

Further variants of the Orion continued to be developed to meet customer needs. These included the “Update II” and “Update III” versions, and the CP-140 Aurora for Canada. The Orion was also built under licence in Japan. The US Government cancelled the Stage IV upgrade programme.

Between 1979 and 1999 the Australian Government obtained four ex-US Navy P-3Bs for the RAAF. One P-3B-75 (c/n 5204 – ex BuAer 152760), which had 14,255 hours on the airframe, was converted to components on its arrival at Edinburgh in 1995, the cockpit section being used as Project Air 5276 Trainer and the fuselage used for Battle Damage Repair Training. The other three aircraft (TAP-3B-85 – A9-434 –  c/n 5231 – BuAer 153434; A9-438 – c/n 5235 – BuAer 153438; A9-439 – c/n 5236 – BuAer 153439) were stripped of surveillance and ASW equipment and were used for general flight training duties to conserve the main fleet’s airframe life in its design role. Operated by No 292 Squadron, they were known as the TAP-3 Orion and continued in service until 2004 when they were retired following the installation of a new advanced flight simulator at Edinburgh. They were put into storage pending a decision as to their fate [see separate article for TAP-3B].

The Orion in Australia has been operated by Nos 10 and 11 Squadrons as part of No 92 Wing, No 292 Squadron carried out type conversion. All Orion units were based at Edinburgh, SA, and continuous detachments have been maintained over the years at Butterworth in Malaysia. The Orion has seen extensive use in the maritime surveillance role, particularly during operations related to the influx of “boat people’, the problems in Timor etc. It continued in service with the RAAF to late 2016 when they were to be replaced, initially by four Boeing P-8 Poseidons.