A Wellington engineer has been censured and fined after an unsafe crane on the back of a truck broke part of the truck chassis.
Dick Joyce has been suspended from Engineering New Zealand and ordered to pay $15,000 after its disciplinary committee upheld a complaint against him.
He had certified the crane after it had failed load testing but another engineer questioned if the truck deck was rigid enough for the crane's size and position.
The crane had been operating for two years under a load rating of 1.3 tonnes that an inspection company estimated was three times higher than was safe, a report shows.
The committee found Mr Joyce's work did not meet the standards expected of a chartered professional engineer.
"The public places significant trust in engineers to self-regulate," the decision said.
"As a professional, an engineer must take responsibility for being competent and acting ethically."
Mr Joyce was earlier suspended as a heavy vehicle certifier by the Transport Agency, which last year revoked some of his certifications of towing connections.
The Engineering NZ investigation report shows Mr Joyce's Seaview company Dick Joyce Consultants did the original calculations to fit the crane to the truck in 2012. It was then certified by another engineer.
But two years later, during testing, at least two wheels lost contact with the ground at a load well below the full crane rating.
"During its load testing the torsion applied to the chassis of the truck broke a cross-member between the chassis rails."
An inspection company told the owner the crane would only be safe if it operated at 29 percent of its load rating.
But a month later, Mr Joyce re-inspected and passed the truck and crane, though the report notes he did not contact the owner or the inspection company.
He had not been able to provide the stability diagram he said he drew up, the ENZ report said.
The owner sought a second opinion, and that engineer found the truck's frame was "grossly inadequate" for the crane.
"The level of calculated twist in the chassis, sub-frame and deck combination suggests that this whole aspect of design was not considered and therefore was not carried out by the design engineer," the second opinion said.
Mr Joyce told the disciplinary committee that the truck had worked faultlessly for two years and that he did not accept the complainant's expert conclusion that the subframe was too small; he suggested it failed the test "due to operator abuse".
An expert he brought in said the truck-crane design was not at fault.
The committee found Mr Joyce breached his professional obligations when he certified the truck in 2014.
Additionally, his record keeping and referencing was of a "very poor standard, or there has been deliberate effort to conceal the lack of engineering consideration taken in July 2014", it said.