The horizon can hoodwink observers peering through the slightly convex portholes set into the side of a P3K Orion. At first it appears horizontal then switches to a vertical line as the big plane pivots around a wing tip in a gut-wrenching turn.

Watching the broad wings carve through the air it’s easy to wonder how many 52-year old rivets are holding it together and what sort of shape they’re in. From 2023 the throaty roar of the turbo-prop engines will be replaced by the whoosh of jet units when four, new P8-A Boeing Poseidon’s take over the watch.

The first hint of the impending aerobatics crackled over the head-phones as the captain worked through the checklist for an anti-submarine warfare (ASW) exercise east of Auckland.

“Oh – and could someone give the passenger a sick bag please?” he added.

I had just munched my way through a big plate of steaming curry. “I hope you’re not prone to seasickness?” a crew member asked as he collected my empty plate a few minutes earlier. “Even if you’ve never been seasick – these things will do it to you.”

The 11-person crew went about its work while the plane pirouetted across the sky. Two pilots, one either side of the cockpit, operated the 36m-long aircraft with a flight engineer seated between them, monitoring its systems. The next seat aft is taken by a radio operator, head-phoned to a bank of radios that include HF (single sideband), marine VHF and other links to air traffic control and shoreside search coordinators.

Next aft, in the small dinette area, I sat watching the porthole view change from sea to sky and back again, bracing against a bulkhead while I struggled to keep my curry down. Finally the big aircraft flattened off and I swallowed great gulps of air as I regained gastric composure.
“Well done,” a rating patted my shoulder, while some of the four “sensor operators” – hunched over radar screens arrayed on the port side of the darkened fuselage – smiled and waved. Among them were two navigators, using inertial navigations system (INS) and GPS to provide the data that keeps the plane on course or aiming at a target.

Pre-flight checks can take up to an hour before the 58-tonne aircraft lifts off her Whenuapai runway and heads at 750kph (405 knots) for the search area. “We get all the information about the target vessel from the National Rescue Coordination Centre (NRCC),” Flight Lieutenant Donaldton explained. “Vessel name, number of people aboard, size, type, colour and rig.”

The Orion crews also take photographs of vessels they see in the course of their regular patrols and keep them in an archive to give them an idea what they’re looking for.

“Why do yachties paint their boats white?” he queried. “They should get the chance to do our job and see how hard it is to see a white boat in rough seas.”

On search and rescue missions the Orion crew is supplemented by up to four observers to help out with the eye work. They are exchanged at 30-minute intervals to prevent eye strain.

After several minutes of aerobatic ballet – or perhaps because the passenger hadn’t used the sick bag – the Orion’s engine tone relaxed and settled into cruise mode. Minimum speed is about 259kph (140 knots) but most search and rescue work is carried out at 370kph (200 knots).
The plane’s maximum range is 7,100km (3,850nm) but, once it arrives at the search area, endurance can be extended to 15 hours by closing down two of the four 4,600bhp Allison T6 engines. An onboard gas turbine generator provides power for the plane’s systems and compressed air for engine starting.

A safety margin of about five percent is kept in her 34,000-litre wing fuel tanks. The navigators also keep a running track of landing options at one of the country’s 16 approved airports.

Although human eyes are a big component in search and rescue work, radar systems (retrofitted in the early 1980s) are also used. The system works on four, eight, 16, 32, 64 and 150nm range scales but it’s effectiveness depends on the plane’s altitude.

“One time we did two day’s flying looking for a missing yacht,” radar observer Sergeant John Fitch recalled. “We didn’t see a thing – not a skerrick. As we were flying home we picked up a faint contact on the radar about 50 miles out. We got all buoyed up – whooping and slapping each other on the back, thinking we’d found it. But it was just a power pole – floating vertically in the water, with about one metre above the surface. We were gutted.”

Yachts stand a much better chance of being found if they use a radar reflector,” he added. “We easily pick up a fibreglass yacht with a metal mast at 15nm. A yacht still carrying a mast is three times easier to pick up than a dismasted one because an aluminium mast gives a much better radar signal. A wooden boat with wooden mast is hardest to pick up.”

The Infrared Detection System (IRDS) can detect a yacht from three to four miles – or a person in the water – by focussing on body heat. Part of the plane’s operational brief is surveillance flights over Antarctica where the IRDS can locate individual penguins by their body heat.

RNZAF 5 Squadron’s Orion brief is wide-ranging. The planes have flown disaster relief missions to cyclone- or tsunami-battered Pacific Islands and sharp-eyed crew members have picked up lost local fishermen, drifting miles from home in small wooden or fibreglass boats. I once met a big, smiling Samoan man named ‘Orion’ who presumably was born about nine months after his father’s rescue.

In 2017, 5 Squadron spent 116 flying hours on nine search and rescue missions and the latest available statistics, from January – June last year, show 127 flying hours taken to carry out seven missions.

But the acme of their search and rescue work was June, 1994, when a fleet of Tonga-bound yachts was hammered by heavy weather. In one of the largest maritime rescue missions ever, the Orion crews flew hundreds of hours in often challenging conditions. Many sailors were saved due to their efforts, but three lives and seven yachts were lost.

The operational altitude range for the Orions is listed as between sea level and 9,150m but crew don lifejackets as soon as they start operating below 305m. “We only have 15 seconds if we’re forced to ditch at that altitude,” Donaldton said. Salt water is washed off the fuselage after extended low-level search and rescue operations.

The RNZAF bought Orion 4201 and four others (4202 – 4205) new in 1966 and another one from the Royal Australian Air Force in 1985. They received a partial electronics upgrade in the 1980s and new wings, stabilisers and engine nacelles during Operation Kestrel in 1997. Further electronic updates were planned for Operation Irius a few years later.

But like a shovel which has had a dozen handles but is still the same shovel, the operational life of the Orions ends in 2025 and the distinctive roar of their huge engines will be gone from our skies.

The four Boeing P8-A Poseidon patrol aircraft that will replace them, come at a price of $2.3billion – including training systems, infrastructure and commissioning costs.

Whenuapai-based Number 5 Squadron has operated the ageing Orions over the millions of square kilometres of ocean that make up our EEZ – fourth largest in the world and the largest search and rescue territory. The squadron is relocating to Ohakea near Bulls where the new planes will have more runway to take off on and space to handle their heavy-duty weaponry.

The Poseidon is no newbie when it comes to surveillance work and it is already operated by the Indian Air Force, RAAF, RAF, USAF, the Royal Norwegian Air Force and Canada.

When they take to our skies in 2023, any seafarers who’ve triggered a Mayday call may not recognise the fuselage but the black kiwi centred in red, white and blue rondels will remain the same.

Lockheed P3K Orion
Wing span 30m
Length 36m
Weight 57.8 tonnes
Payload 9,000kg
Speed 750 km/h
Ceiling 9,150m
Range 7,100km
Crew 11

 Boeing P-8A Poseidon
Wing span 37.64m
Length 39.47m
Weight 62 tonnes
Payload 26,400kg
Speed 902 km/h
Ceiling 12,496m
Range 22,200km (with four hours on station)
Crew 9