The Civil Aviation Authority has confirmed it will carry out an inquiry into the emergency landing of a passenger aircraft in Blenheim this month.
A spokesman for the authority said on last week it would be "actively assisting the operator in their investigation into the incident".
The Sounds Air flight from Wellington was bound for Koromiko on December 18 when it diverted to Marlborough Airport after a loud bang that was heard in the cockpit about 10 minutes into the flight.
The company said that after landing, it was discovered a heat shield between the engine exhaust and the cargo pod of the plane had come loose during the flight. It then fell off as the plane landed.
Alan Riwaka, one of six passengers on the flight, said he hoped there would be a full investigation because "those things don't just fall off".
The incident prompted him to ask how secure the rest of the aircraft was, he said.
The Civil Aviation Authority spokesman said its role in the investigation would be "desk-based", which included using all known facts and reports leading up to the incident.
It was not known how long the investigation would take, although the authority's communications manager, Mike Richards said last week they were still gathering the necessary information.
"So far we have learnt that the aeroplane did not have an engine problem. It [the loose heat shield] was causing vibration [and] it seems the pilot thought the vibration was an engine issue, so as a precaution he diverted into Blenheim, where he declared an emergency."
After realising the engine was performing normally, the pilot made a safe landing, Mr Richards said.
Sounds Air managing director Andrew Crawford said last week the incident had been "very minor".
He had spoken to the passengers following the flight, and had further apologised that night.
The Transport Accident Investigation Commission said it would not be investigating the incident.
- The Marlborough Express