Labour is pushing for the release of a Defence Force report into the Anzac Day Iroquois crash, which killed three airmen.
A court of inquiry into the 2010 crash at Pukerua Bay, north of Wellington, blamed a culture of rule-breaking and inadequately-trained Royal New Zealand Air Force squadrons.
An accident analysis report formed part of the inquiry but has not so far been made public, despite the New Zealand Herald publishing excerpts from it in recent weeks.
The latest claims allege the Defence Force made the early-morning flight to avoid paying hotel bills.
Defence Minister Jonathan Coleman says legal reasons prevent him releasing the report.
But Labour defence spokesperson Iain Lees-Galloway says it can't be withheld any longer in the interests of transparency.
The Labour Party has been trying to point the finger at Government cost-cutting as a factor in the crash on a hillside while en route to a dawn ceremony in the capital. A fourth airman was seriously injured.
In Parliament on Wednesday, Labour's defence spokesperson Iain Lees-Galloway asked Dr Coleman if the report indicated that the decision not to have the crew accommodated in Wellington the night before, - which he says is standard practice - was to avoid costs of about $600.
But Dr Coleman said the Court of Inquiry, which used the same report, did not identify budgetary considerations as a cause of the crash.