Killer hovercraft's failure 'inevitable'

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A home-made hovercraft that killed its creator earlier this year was "structurally on the light side" and structural failure was "inevitable".

Waitakere man Alastair Senior died instantly after the spinning propeller of his homemade hovercraft struck his head during a test run on Muriwai Beach, west of Auckland, on July 31 this year.

Coroner JP Ryan said an inspection by a marine engineer and ship surveyor who has experience with hovercraft found the hovercraft was "structural on the light side, and that structural failures were inevitable".

The engineer's report found the "overall condition of the craft creates an impression of urgency by the owner to make the hovercraft functional, well before it was viable or safe to do so", Coroner Ryan wrote.

"This is indicated by a significant number of aspects of the construction which had not been completed prior to the test run, such as a mechanism for steering the craft, a seat and seatbelt for the pilot, and a safety grill for the lift fan."

The engineer said there should have been a static or tethered trial to ensure the viability of Mr Senior's craft.

"If such a trial had been performed, then the structural failure which occurred may not have had serious, let alone fatal, consequences."

In his findings, Coroner Ryan said the death was avoidable.

"This death was accident only in the sense that it was not intended. It was not an accident in the sense of being an event that happened by chance or that is without deliberate cause. This death could have been avoided."