By Christopher Testa, ABC News
Flames coul be seen coming from the helicopter when it crashed. Photo: Twitter / Ghulam Abbas Shah
The wreckage of a helicopter that crashed into a Far North Queensland hotel roof while on an "unauthorised flight" has been removed overnight.
Investigators will return to the DoubleTree hotel on Cairns Esplanade on Tuesday as they probe what happened before the allegedly stolen craft crashed, killing the pilot and injuring two hotel guests.
Nearly 400 people were evacuated after the helicopter hit the hotel shortly before 2am on Monday.
Two hotel guests - a man in his 80s and a woman in her 70s - were taken to Cairns Hospital in a stable condition and have since been discharged.
Police are yet to identify the pilot but Nautilus Aviation, the charter company that owned the helicopter, said the flight was "unauthorised".
Investigators believe the helicopter, a Robinson 44, was taken from the general aviation wing at Cairns Airport, where Nautilus has a hangar, and flown to the CBD, which is a no-fly zone.
Witnesses reported seeing the helicopter fly at high speed and low to the ground along the foreshore before crashing into the building.
Nautilus Aviation CEO Aaron Finn was unavailable for an interview yesterday but told the ABC the helicopter was "stolen" and all his company's pilots were accounted for and safe.
Emergency services at the scene. Photo: Supplied / Queensland Ambulance Service
'No compromise' of airport security
Cairns Airport chief executive Richard Barker said the airport was helping authorities with their formal investigation.
"Cairns Airport operates under an approved multi-layered transport security program," Barker said.
"We have conducted a review this morning and initial findings show there has been no compromise of the airport security program or processes."
Doug Drury, head of aviation at CQUniversity, said it was likely the pilot gained access either by using a code to enter the company's hangar or by climbing over the fence.
Professor Drury said general aviation companies used keypads with codes to restrict access to the airside part of the airport.
"I've used them in airports all over the world but it's a common code and if you've ever worked at this location, then you would know where to go and how to get in," he said.
"They do change the codes and I imagine every facility at Cairns Airport now has a new code in their door and in their gate locks.
"I would say [the pilot] knew what they were doing, whoever it was, [and] they knew how to get in."
Professor Drury said the incident would force airports around the world to reconsider their airside security.
He said Cairns Airport security was "right up there with everybody else's" but it was "a given that the security presence will increase".
"They'll go through footage from all the security cameras to see how this person got in and how they were able to start the aircraft," he said.
The Australian Federal Police said it was assisting the Queensland Police Service with inquiries related to the events at the airport and its surrounds.
It did not confirm whether an aviation security identification card (ASIC) was used to access the airside area.
Photo: Supplied / Queensland Ambulance Service
Investigations continue
Australian Transport Safety Bureau (ATSB) chief commissioner Angus Mitchell said his organisation's investigation would focus on the sequence of events that led to the crash.
ATSB officers were at the scene yesterday, combing through the evidence.
They collected the helicopter's rotor blade, which had landed on the Cairns Esplanade opposite the hotel.
"We'll gather as much evidence over the coming days as we can and piece together the flight itself and anything that's pertinent about that around the helicopter itself, what it was equipped for, how it was accessed, the purpose of the flight," Mitchell said.
"If we can get a better understanding of that and of the actual impact, then that helps us in other investigations as well.
"But in terms of greater benefit, in terms of learning that we can get from this, well, it's a bit too early for us to make any determination."
However, Mitchell said airport security and airside access would be issues for police or the Department of Home Affairs to address.
- ABC