On
the 3rd of July 1987 Eagle Air withdrew their air service through Wanganui. Eagle
Air has been operating the service to Hamilton since the mid-1970s with the
extension to Auckland added in 1980 with the purchase of its first Embraer
Bandeirante.
Within
five days Noel Oxnam, the owner of Foxpine Air Charter, announced that a new,
unnamed airline, would use a leased Eagle Air 10-seater Piper Chieftain to make
two return flights between Auckland and Wanganui on Mondays, Wednesdays and
Fridays with flights departing Wanganui at 7.30am and 4.00pm and Auckland at
9.00am and 5.30pm. The airline also planned to operate two return trips between
Wanganui and Hamilton on Tuesdays and Thursdays with flights departing Wanganui
at 7.30am and 4.00pm and Hamilton at 8.40am and 5.15pm.
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| Air River City timetable, effective 3 August 1987 The timetable features a Cessna 402 which the company had initially thought it would use before selecting a Piper Chieftain |
The
new Wanganui commuter-based air service was subsequently called Air River City.
Noel Oxnam told the Wanganui Chronicle that the chosen name clearly advertised
Wanganui. The airline was acquiring its own Piper Chieftain which "is
being refurbished and painted,” he said, but this never eventuated.
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| Waikato Times, 10 October 1987 |
Services started on the 3rd of August 1987 with the first flight being by Graeme Atchinson and owner and co-pilot Noel Oxnam in Piper Chieftain ZK-FIA. The passengers included Wanganui Mayor Chas Poynter, City council transport committee chairman Barry Pull and Hospitality Wanganui promotional officer Evert van Reenan. Graeme Atchinson recounts, I flew Piper Pa31-350 Chieftain ZK-FIA from Wanganui to Auckland and returning directly to Wanganui. There was no Hamilton service that morning. On the same day in the afternoon I delivered ZK-FIA back to Hamilton and Eagle Air transported me to Auckland. Noel Oxnam flew ZK-EQA from Wanganui to Auckland that same afternoon and I returned to Wanganui as a passenger. On the 5th August 1987, I flew the full published route Wanganui-Auckland-Hamilton-Wanganui.
The company’s initial plans to use a Piper Chieftain ran into problems as this required a Category B air transport licence while Foxpine Air Charter only had a Category C licence and so the Chieftain was substituted with Piper Seneca ZK-EQA.
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| The inaugural Air River City service was flown in Eagle Air's Piper Chieftain ZK-FIA. It is seen here at Palmerston North on 24 February 1985. |
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| Foxpine Air Charter's Piper Seneca ZK-EQA was the mainstay of the Air River City service. It was photographed at Wanganui on 28 November 1987. |
The
air services from Wanganui did not prove profitable and by early May 1988 the
decision had been made to withdraw from the routes and negotiations had been
held with another operator to “buy the licence.” The formal scheduled services ended on the
6th of May 1988.
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| Foxpine Air Charter's Piper Twin Comanche ZK-ECS at Matamata on 14 February 1987 |
On
the evening of the 12th of May 1988 the Seneca ZK-EQA was being used to operate
some of the last flights for pre-booked passengers. Having completed an Auckland to Hamilton sector it
left just on dark, in fine weather, from Hamilton bound for Wanganui. On board
were the pilot, Noel Oxnam, and eight passengers. However, on the flightpath
ahead a line of thunderstorms was rolling over Wanganui, bringing strong winds and
turbulence across inland ridges. As the plane headed south air traffic
controllers at Ohakea warned the pilot that he was wandering off course.
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| Piper Seneca ZK-EQA at Hamilton on an Air River City service on 29 September 1987 |
The
plane never arrived in Wanganui. The aircraft was found in the Ahu Ahu Valley the
following day with its undercarriage down, and with one "notch" of
flaps deployed. There were no survivors.
The
accident investigation, drawing on eye and ear witness accounts, developed a
theory that the plane was on a flight path almost identical to the NDB approach
into Wanganui. Due to the winds the plane was over the valley at the time it
should have been over Wanganui. The theory suggested that the pilot may have
received a false signal from the Wanganui NDB, some 40 kilometres south
disorientating the pilot. The Wanganui NDB was weak towards the north, its
prescribed range was only 15 miles. Radar coverage at the altitude flown in the
area faded around the valley as the signal was blocked by higher terrain. The
pilot had been told he was fading from the air traffic controllers' radar.
This
initial conclusion raised many questions and so a Commission of Inquiry was
established. This brought out new conclusions. No fault was found with the
Wanganui NDB and the report stated that it was safe and reliable provided the published warnings
and limitations were observed. It was clear that some maintenance work on the
Seneca had been done by non-approved engineers. The Air Transport Division was
found to have failed to monitor the airline to the necessary standards and
serious systematic problems within the Division. The pilot’s licence,
instrument rating and medical had all expired and his logbook showed his last
night flight was five months before the crash. The aircraft’s instrument check
was overdue and its automatic pilot was not fully functioning its maintenance
release was only for VFR flights.
Evidence
was presented that the plane had impacted in a very steep right hand spiral
dive. It was at least 136 kilograms over its maximum permissible weight and its
centre of gravity would have been several centimetres behind its maximum limit.
It was reported at the time of departure the pilot was forcing baggage into
the lockers and there were nine people in a six seater. It was concluded that that
the plane would have become increasingly unstable as fuel was used, and given
the turbulence it became uncontrollable The aircraft manufacturer was reported
as saying a stall and spin were probable if the centre of gravity was behind
the limit.
The
court of inquiry reported back within two weeks of hearing the final
submissions. It said it could not conclude the exact cause of the accident. But
it said it was highly probable the tragedy was a combination of the plane being
over-laden and with its load too far to the rear, resulting in a loss of
stability. This was worsened by severe turbulence that could have disoriented
Oxnam and resulted in distress and confusion in the crowded cabin that would
have placed him under considerable stress. The Seneca may have gone out of
control but upon recovery in the valley, the plane stalled and spiralled into
the hillside as Oxnam tried to climb away. The landing gear was down and the
flaps deployed in a vain attempt to control its rapidly fluctuating speed,
caused by its instability.
