KEY POINTS:
Police have named the two men who died after a home-made plane stalled in midair and nosedived into an Air Force base late yesterday afternoon.
They were Wayne Matthews, 62, of Greenhithe and Brent Baldwin, 46, of West Harbour.
The Thorp S-18 was built and owned by Matthews, a record-breaking airman, retired air force navigator and vice-president of the Sport Aircraft Association.
Witness Phil O'Kell was watching planes fly over the Royal New Zealand Air Force base at Whenuapai, West Auckland, with his wife and son when the light aircraft flew over at about 4.30pm.
He said the two-seater had a tailwind when it flew over the base before making a sharp right-hand turn and stalling.
"He went into a nosedive on a very steep angle. I thought, 'gee, he's not going to pull out of that in a hurry'," said O'Kell.
"He ploughed into the ground, there was quite a plume of smoke, then an explosion - a big flash."
Base personnel sent medical attention and a fire rescue team. About a dozen fire trucks and ambulances were sent to the scene as the base was sealed off to the public.
RNZAF spokesman Squadron Leader Glenn Davis said the base would remain secured overnight before the Civil Aviation Authority (CAA) started its investigation this morning.
The plane crashed in a small space between the headquarters of 40 Squadron - who fly Hercules and Boeing aircraft - and the base administration block, about 200m left of Whenuapai's main runway.
A few mechanics were working in the 40 Squadron building and Davis said it was "bloody lucky" the aircraft didn't plunge into the base barracks.
He said the Air Force was not investigating because it was a civilian aircraft.
CAA spokesman Bill Sommer said two investigators would be at the base by noon today and carry out the "standard accident investigation".
"We don't have the details at the moment and couldn't possibly speculate on the cause."
Matthews, a married father-of-three, built the plane - nicknamed Rosie - from scratch in the garage of his Greenhithe home over five years.
Neighbours last night told the Herald on Sunday he refused to let anyone else fly it.
The high-performance aircraft can reach speeds of 320km/h but is small enough to be stored in a garage.
Matthews flew the craft on a solo, non-stop circumnavigation of New Zealand earlier this year, a 3374km journey he completed in a world record 15 hours and 53 minutes.
"It was a beautiful moonlit night. I flew over the Southern Alps at sunset and could see the city lights of Christchurch, Wellington and Napier," he told a local newspaper.
Five years ago, Matthews publicly defended the safety of custom-built planes after seven people died in three accidents in the space of a month.
He said their negative image was due to the names they were given, such as homemade, amateur or experimental class.
"It makes people think the planes have been cobbled together with a bit of string," Matthews told the New Zealand Herald in 2003.
"I go the extra mile because I know I will be the one flying it."
The experienced aviator, who learned to fly during his retirement, had flown to Australia and back and clocked up 500 flying hours in different planes.
Sport Aircraft Association of New Zealand vice-president Alistair McLachlan said he had known Matthews for many years and he was a "careful and meticulous pilot".
"He was a Wing Commander in the Air Force. He was pretty cagey - pretty cautious. He's a confident pilot and a sensible character."
McLachlan was involved in the inspection of Matthews' homemade aircraft and said the Thorp was reliable and "generally better quality than commercial planes".
"It's made of aluminium, standard aircraft materials, with a normal aircraft engine, 160 horsepower."
While the identity of the two men killed in the crash had not been confirmed as the Herald on Sunday went to press, McLachlan said it was hard to believe a plane piloted by an aviator as competent as Matthews could crash.
"It sounds pretty unusual... it seems strange."
Even if the engine had failed, an experienced pilot should have been able to complete an emergency landing, said McLachlan.
An unnamed source said if he ever wanted anyone to fix his aeroplane engine it would have been Matthews.
"He's a very experienced engine mechanic."
Matthews led a Saturday group from the base's Aviation Sports Club on pleasure flights to other airfields.
He joined the Air Force in 1965 as a trainee engine fitter, before qualifying as a navigator in 1972.
He had extended postings in Australia, Singapore and Washington, where he spent four years at the Pentagon, part of which was during the first Gulf War in 1990-1991.
On his return to New Zealand, he made the Air Staff's director of operational requirements before retiring aged 47.
He learned to fly after restoring a 33ft kauri keeler and sailing it single-handed along New Zealand's north-east coast.
Whenuapai Aviation Club captain Dave Cogan said both men had been very involved in the club for the past 10 years and they were exceptional people.
The Civil Aviation Authority says it could take several days for investigators to determine the cause of the crash.
PREVIOUS CRASHES INVOLVING WHENUAPAI
July 3, 1963: National Airways Corporation DC3, ZK-AYZ crashed in the Kaimai Ranges, killing all 23 people on board, en route to Tauranga from Whenuapai.
July 28, 2005: Firefighters and ambulances turned out in numbers to the Air Force's Whenuapai base after an engine compressor stalled on a Boeing 757 about 600m above North Shore City. The 12-year-old Boeing flew out to sea to burn off excess fuel, before landing safely back at Whenuapai.
Nov 4, 2006: Five parachutists bailed out of a smoking plane 3000ft over Auckland when their Cessna's engine failed after taking off from Whenuapai. Pilot Marc Saad flipped on a power line and landed upside down in a Kumeu vineyard but escaped with minor injuries.
- with NZPA, NEWSTALK ZB
