Defence Minister Wayne Mapp says the Prime Minister's use of an Air Force Iroquois helicopter on Saturday was appropriate and perfectly reasonable.
Mr Key was flown from Auckland to Hamilton and back, so he could attend both the V8s racing and a golf club dinner.
The Labour and Green parties have labelled the trip extravagant and disgraceful.
Dr Mapp says when Mr Key has accepted an invitation it is important he show up and he disagrees with criticism of the use of the Iroquois.
He told Morning Report the Prime Minister often has to be in different places within a short time and it is perfectly reasonable that he would use an Iroquois, as have previous Prime Ministers.
Labour's associate finance spokesperson, Trevor Mallard, says using a helicopter was slower than using a car in this instance, and even if there was extra time involved it was an expensive exercise and one which should not be happening.
The Air Force has confirmed Mr Key has used the helicopters four times since 31 March.
Radio New Zealand : News : Political : Minister defends PM's use of Iroquois
Kiwi's should be pleased that there is no legislation requiring their PM to be transported in a twin with two pilots as that would cost them even more!
Sav