A police mechanic found no mechanical faults with the braking system of a bus which crashed and killed an 11-year-old girl on Mt Ruapehu two years ago, he says.
The inquest into the death of Hannah Francis is now in its sixth day, analysing a post-crash inspection of the bus. She died when a mountain shuttle bus, operated by Ruapehu Alpine Lifts, lost control and hit a bank at speed with 30 other passengers on board.
The driver said the brakes stopped working and he could not slow down, nor get the bus in gear to slow down using the engine.
Police mechanic Brenton Wallace assessed the bus in the days after the crash. He found there was air in the tanks for the air-over-hydraulic brakes to operate, and enough brake lining for their effective use.
"The brakes had been hot, obviously, going up and down the mountain - [there] was nothing untoward... that wouldn't have been normal," Wallace said.
"I found no faults with the braking system mechanically, no," Wallace said.
Olivia Lund, the lawyer for the driver, who cannot be named, said there may have been faults with the clutch which made it hard for the driver to depress and get into gear.
"Do you accept that a faulty or leaking clutch servo would make it more difficult to operate, and pose a hindrance to that clutch actuation, and then prevent gear change?" Lund asked.
"With no air in the system, it would make the gear shifting harder, but it still makes it possible," Wallace replied.
She asked if there was a fluid leak from the servo and there was a loss of air pressure, if that would have made it more difficult for the driver to change gears, to which Wallace agreed was possible.
"Is it possible, Mr Wallace, that you only viewed the clutch servo from underneath the bus, and you didn't actually see the fluid leak?" Lund asked.
"I saw the leak - well, I don't see it as a hydraulic fluid leak," Wallace replied.
Wallace also said the handbrake was found engaged fully in his assessment.
Lawyers earlier said passengers had smelled burning brakes before the crash. Lund asked Wallace if the 'burning brake' smell could have been caused by the handbrake being engaged while it was moving, to which Wallace agreed it was possible.