Ex-military helicopters face civilian restraints

The use of ex-military helicopters for civilian work will be restricted after a review found they had 10 times the fatality rate of all other civilian helicopters.

The review by the Civil Aviation Authority revealed that some of the former military helicopters were operating significantly outside their design limits and without necessary maintenance.

The authority began the review about a year ago after accidents involving three former military helicopters resulted in five deaths, including a Bell Iroquois which crashed on Mt Victoria in Wellington in January last year, killing its pilot.

The review also found that ex-military helicopters had an incident rate of two to five times that of all other helicopters and sometimes the only formal training civilian pilots received was a type rating to fly the aircraft.

The authority's general manager of general aviation, John Lanham, said 15 ex-military helicopters were operating in New Zealand, all of them imported.

"The critical problem with these aircraft is that they were designed as utility aircraft for the military to use."

They were designed to fly around a battlefield carrying about a dozen troops with the occasional lift of a piece of heavy equipment such as artillery.

However, most civilian owners were using them for logging and other heavy lifting work, Mr Lanham said.

In the case of logging, this might involve up to 25 deadweight lifts an hour, all at maximum engine power.

"That is just completely out of the design parameters that they were intended to be used for."

As a result, the fatigue life of the helicopters could be used up 2000 times faster than anticipated by the manufacturer, Mr Lanham said.

Military helicopters were also almost always flown by two pilots and maintained by specialist engineers, supported by a wealth of knowledge built up over years of experience in operating large fleets.

In civil operations, the helicopters could be flown by one pilot who was often isolated from any support or peers.

The review recommends that former military helicopters in New Zealand be "ring fenced" and some restrictions might be placed on their use.

Mr Lanham said the authority would work with the helicopter operators over the next two years to improve the maintenance and airworthiness standards for the machines and introduce operating limitations where needed.

Ex-military helicopters would have to meet higher standards in future to gain certification to fly here.

The machines were attractive to operators because they could be bought for as little as US$100,000 ($210,000) or 10 per cent of the cost of equivalent civilian helicopters.

Mr Lanham said the issue had become more urgent because the United States armed forces were expected to sell a large number of helicopters into the world market over the next few years, which would exacerbate the problem.

- NZPA