Project Kestrel

By the early 1990s the Orions had been in service for a quarter of a century, and were amongst some of the most intensively used aircraft of their type in the world. The fleet now consisted of six aircraft, a further aircraft having been purchased second-hand from the Royal Australian Air Force (RAAF) in 1985, at a cost NZ$19 million. In 1993 a fatigue analysis was undertaken, which showed that the aircraft had been used to such an extent that their fatigue life index was 135 against a baseline index of 100. This was quite a remarkable figure compared with the US Navy Orions, most of which were retired at fatigue life indices between 60 and 80.[14]

By this stage it was clear that, in most circumstances, the most favoured replacement for an old Orion was a new one, and amongst the options reviewed was that of purchasing new aircraft. But, at a cost of NZ$1 billion, that was unlikely.[15] Other options then explored included the possible purchase of new airframes and then transferring engines and sensors from current aircraft, at an estimated cost of NZ$600 million; refurbishing second-hand aircraft purchased from the United States; or undertaking significant structural refurbishment of the current aircraft by replacing major structural panels.[16] Engineering studies were undertaken by Lockheed Martin, and these confirmed that it was possible to replace significant structural portions of the aircraft with a low engineering risk associated with the project. Completion of the project would extend the life of the aircraft by 20 years.[17]

Project Kestrel was to be a world first, and was truly an international project. Wings, horizontal stabilisers, and engine nacelles were all to be replaced. The outer-wing panels were to be manufactured in South Korea; the horizontal stabilisers were built by British Aerosystems in the United Kingdom; and the centre wing section lower skin came from Lockheed Martin in Georgia in the United States.[18] Engine nacelles were refurbished by Celsius Hawker Pacific in Australia, and the installation of components and completion of the refurbished aircraft was undertaken by Hawker Pacific in Sydney.[19]

Project Kestrel was, like Project Rigel a two-phase project. Unlike Project Rigel, Kestrel was completed on time and on budget, with a total cost of less than NZ$100 million—one tenth of the cost of new aircraft. Work had begun on the re-integration phase on the first aircraft in November 1997, and the final aircraft returned to RNZAF service on 21 August 2001. The Air Component Commander at the time, Air Commodore John Hamilton, commented:

The concept is complex but has been built on the knowledge, innovation, skills and abilities of Air Force engineering personnel—engineering and design skills that were not readily available offshore except in the aircraft’s original design office. It exemplifies what can be done by New Zealanders with the right background and opportunities.

No-one, not even Lockheed Martin, had ever re-winged a P-5B Orion with P-5C wings, the only ones now available new. The RNZAF project team worked with Lockheed Martin to develop the interface design and the reassembly protocol, and the project was a complete success. Air Commodore John Hamilton added:

It has given the Air Force a significant extension in the life of the Orion fleet at a reasonable cost. The Orion is now well placed to take on upgraded sensors and equipment which will allow them to serve New Zealand’s interests for another 20 years.[20]

Updating sensors and avionics equipment had never been completed under Project Rigel. This deficit was intended to be rectified by the implementation of Project Sirius.




[14] ‘What’s the Latest with Project Kestrel’, p. 6.

[15] Martyn Gosling, ‘New Wings for a Watchdog’, New Zealand Defence Quarterly, no. 18, Spring 1997, p. 19.

[16] Colin James, ‘Rewinging an Old Warrior’, New Zealand Defence Quarterly, no. 23, Summer 1998, p. 18.

[17] What’s the Latest with Project Kestrel’, p. 6.

[18] ‘Contract signed for Kestrel integration’, RNZAF News, July 1997, vol. I, p. 16.

[19] ‘Project Kestrel Completed’, Air Force News, no. 19, September 2001, p. 7.

[20] ‘Project Kestrel Completed’, pp. 7–8.