Technical faults were discovered on an Air Force plane before it left New Zealand, and before it broke down in Australia last year, leaving John Key and dozens of dignitaries stranded overnight.
The then-Prime Minister and his planeload of guests were headed to India for a three-day trade mission, but the breakdown meant the trip was cut in half, with the New Delhi leg cancelled and a handful of important meetings scrapped.
Documents released to Newshub under the Official Information Act reveal Air Force officials were told about two faults before the Boeing 757 took off from Auckland's Whenuapai air base on October 24.
Just before taking to the skies at 7am, two problems called Limitations-Acceptable Deferred Rectifications (LADRs) were reported.
These are faults that require fixing but aren't considered serious enough to ground the aircraft. The faults were:
- One of two GPS receivers wasn't working because a circuit breaker kept popping and wouldn't reset. The receiver is an important navigational aid, and supplies accurate aircraft positioning data to the cockpit
- The plane's auto-speedbrake was faulty, meaning it could only be operated manually. Speedbrakes are flaps on top of the wings that open upwards to disrupt the airflow and slow the plane down. They are also called spoilers.
The flight was carrying then-Prime Minister John Key, his staff, business delegates, journalists and Air Force staff, and was headed to the Indian capital via Townsville, Australia and Jakarta, Indonesia.
But the plane was grounded in Townsville after a similar but unrelated speedbrake fault forced pilots to abort two take-offs.
The fault was:
- A takeoff configuration warning alarm caused by an open circuit fault. It was narrowed down to a broken microswitch incorrectly reading the position of the speedbrakes.
An Air Force spokesperson says the fault discovered in Townsville was unrelated to those discovered prior to departure from Whenuapai.
"Although the spoiler and speed brake systems do share common flight control surfaces on the wings, the control and indication systems for spoilers and speedbrakes are quite separate systems so the two faults were unrelated," the spokesperson told Newshub.
"Although the faulty microswitch was repaired in Townsville to rectify the spoiler fault, the auto speedbrake fault remained as no work was conducted on that system.
"This fault continued to be carried until the next scheduled 'A' Check which was two weeks later," the spokesperson says.
A replacement plane was sent in the following day so the trip could continue, albeit with a shortened itinerary.
The 757s are earmarked for retirement early next decade because of their age and their inability to fly to Antarctica and back without the need to refuel.
They are old aircraft, with one built in 1992 and the other in 1993. The Government purchased them secondhand from Dutch airline Transavia in 2003, modifying them in 2007 to make them fully convertible between freight and passenger configurations.
The OIA documents refer to the age of the plane becoming more problematic for its reliability.
"There are maintenance issues that are beginning to manifest themselves more and more. Examples are the recent unscheduled engine changes, wing tank corrosion repairs, hydraulic pipe issues, and passenger seat rectification issues," a briefing note to the Chief of Defence says.
"All of these are an indication that the aircraft is beginning to age."
Defence Minister Gerry Brownlee didn't want to comment on the revelations, with a spokesperson saying "the response to the OIA provides decent detail about the faults and actions taken, according to Boeing procedures".