Ministry of Defence officials seriously considered buying two of Air New Zealand's old 767-300ER aircraft as a replacement for the Air Force's current Boeing 757-200 fleet.
The idea was abandoned because they were too big, too old, and would have required extensive modifications and changes to ground handling procedures.
New Zealand First MP Ron Mark uncovered the details in an Official Information Act request, showing a briefing was given to Defence Minister Gerry Brownlee about the rejected purchase.
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.
The national carrier put two of its 767 planes on the market last year because it's replacing them with more fuel-efficient 787 Dreamliners.
Both planes are nearly two decades old, and operated on Air New Zealand's long-haul routes to Tokyo, Honolulu, and Perth.
The briefing to Mr Brownlee concluded the 767 would not be the right fit into the Air Force fleet because it didn't tick enough boxes.
"There are significant risks around operating costs and the overall reliability of the aircraft. These risks will increase over time," it says.
"Over time, significantly more capital would be required to refurbish the aircraft for extended service, modify infrastructure to properly accommodate larger aircraft, and fully exploit the performance potential."
One of the only benefits was its long range, meaning it could fly to Antarctica and back on one tank of fuel, which eliminated the risk associated with adverse weather events on the ice.
It could also fly non-stop to Asia and the United States, which is impossible in the current 757s due to a lack of range.
There would be challenges taking off and landing the 767 from most New Zealand airports, including Whenuapai Air Base and Wellington Airport.