By Savannah Meacham in Brisbane

The pilot who died in a helicopter crash on a hotel roof wasn’t a novice and had knowledge of the aircraft’s hangar security, an expert says.

Authorities are yet to identify the pilot of the unauthorised flight after the fatal crash in far north Queensland on Monday.

Hundreds of guests were evacuated and two people hospitalised after the “massive explosion” at DoubleTree by Hilton in Cairns.

Investigators are yet to shed light on the circumstances after the helicopter’s wreckage was removed from the hotel late on Monday.

Aviation expert Peter Carter said the pilot would have needed basic helicopter flying skills and may have been a former employee of the chopper’s owners Nautilus Aviation.

Authorities have declined to say if the pilot had a licence or how the helicopter was flown out of Cairns airport without authorisation.

“It could have been a student pilot or a licensed pilot … a former employee, perhaps,” aviation lawyer Mr Carter told AAP.

Police would not confirm if the chopper was stolen but on Monday said it had been “moved” from Cairns airport’s general aviation hanger without authorisation.

Nautilus Aviation confirmed it owned the four-seater Robinson 44 helicopter and it had been an “unauthorised” flight.

Mr Carter said the pilot would have needed to know security information to access the aircraft hangar.

“One of the focuses of the inquiry …(is) how sufficient that method of security is,” the Carter Capner Law director said.

The crash probe is expected to involve the Department of Home Affairs, which oversees airport security.

Cairns Airport said a review indicated site access had not been compromised.

“Our thoughts are with all affected by the distressing incident at Cairns Esplanade yesterday,” Cairns Airport CEO Richard Barker said.

“Cairns Airport operates under a federally approved, multi-layered transport security program.

“To reassure our community, we wish to confirm a review has been conducted, showing no compromise of our airport fence or access points.”

The helicopter was seen flying for at least five minutes in the Cairns CBD before it crashed into the hotel roof, smashing the windows of nearby rooms with one occupied by a sleeping elderly couple.

The hotel guests, a man in his 80s and a woman in her 70s, were taken to hospital for smoke inhalation and have since been released.

Mr Carter said night flying required more concentration and could have contributed to the crash.

“If it was an accident, it probably was a factor that it was in darkness,” he said.

Investigators hope to learn more from the recorded data from the helicopter that has been sent for analysis.

“Flying a helicopter, getting it up off the ground isn’t something that anyone could do,” Australian Transport Safety Bureau Chief Commissioner Angus Mitchell told ABC radio on Tuesday.

“You do need to have someone that has quite a detailed knowledge of the helicopter itself and how to fly it.”