Two wheels rolled along the road beside a Ritchies' school bus on Wednesday after coming off near Wainihinihi, east of Kumara.
The incident comes only two weeks after two students had to grab the steering wheel and work the gears of another Ritchies' bus, when the 82-year-old driver became ill while driving near Dobson.
Retired farmer Patrick Fitzgerald witnessed the latest incident, in which two rear wheels bounced off the bus as it was travelling along State highway 73.
"I was entering a farm track off the state highway when I saw the school bus coming down the road.
"I noticed the tyres bouncing along the road - one of them hit the top of a deer fence and the other went through the open gateway I'd just passed through.''
Mr Fitzgerald said the axle the wheels had come off had fallen on to the road and the bus driver stopped immediately.
He took the only remaining student to her drop-off point at nearby Aickens.
A Ritchies' mechanic was sent out from Greymouth and an Aratuna Freighters' truck driver stopped to provide a jack to raise the bus.
Ritchies' director Andrew Ritchie, of Auckland, said this morning Friday he had been told only one wheel came off the axle, not two.
There was no danger to the driver or the student passenger, as the other rear axle was still holding the bus up, he said.
"It's a three-axle bus, and one wheel came loose. It didn't fly past the bus.
"You could drive it all around the country like that, not that we want that kind of thing to happen. It's the first time an incident like this has occurred on the Coast.''
Mr Ritchie said there was never any danger of an accident occurring because of the wheel mishap.
"That would 100% never have happened. It was not an acceptable thing that happened, but there was no danger.''
He said all his buses were checked regularly, and this incident was probably the result of an error by one of the tyre fitters.
"Things have been tightened up around the workshop as a result.''
- Matt Kersten, Greymouth Star
