Paul Chapman in Wellington Published: 6:04PM BST 09 Sep 2010
British born Stephen Wilce also said that he had combat experience with Britain's Royal Marines and designed guidance systems for Britain's Polaris missile.
As chief military scientist for the past five years, leading a team of 80 in the secretive Defence Technology Agency, Mr Wilce had access to sensitive classified material at the highest level.
The agency provides important advice to the military on technology and scientific matters, such as surveillance and defence systems, as well as to the government on threats to air force aircraft in Afghanistan.
The disclosure of Mr Wilce's "Walter Mitty" past were made on New Zealand's current affairs programme, 60 Minutes.
It reported that Mr Wilce had claimed to be a member of the British bobsleigh team at the 1988 Calgary Olympics and that he was in the team which competed against Jamaica during the contest that inspired the 1993 film Cool Runnings.
It screened footage in which he told an undercover reporter: "I know all the Jamaican guys ... mad, absolute nutters."
However, on further research, no one in the 1988 British bobsleigh team had heard of him. There are no records of Mr Wilce serving in the Royal Marines or having combat experience.
Steven Saunders, a business consultant, told the programme that while interviewing Mr Wilce for a top position with his company in the early 1990s he realised he was being misled "from the outset".
"I found this fellow was telling me massive porkies," he said.
The programme also reported that at one previous workplace Mr Wilce was known as "Walter Mitty", a reference to US author James Thurber's fictional character who lives in a fantasy world.
The disclosure have been an embarrassing episode for New Zealand's government.
Wayne Mapp, the Defence Minister, has ordered a full report on Mr Wilce's employment and what background checks were carried out on him.
"I absolutely want to see that this sort of thing would never happen again," Mr Mapp said. "It is not acceptable."
Concerns about Mr Wilce's past are understood to have been first raised with defence officials by a whistle-blower in July, and he continued to work while an investigation was under way.
Keith Locke, a member of the opposition Green Party, said: "If there can be such a failure in this case we have to wonder how many other times the system failed, and we're talking here about someone who should have had the most rigorous of checks."
