A TOURIST who drowned while diving in Australia’s Great Barrier Reef went missing after her instructor strayed from the planned route and then looked away from the dive group, an inquest has heard.

Bethany Farrell was travelling with friends and was just several weeks into a gap year when she drowned in 2015.

She was on her first scuba dive, at Blue Pearl Bay, a popular diving spot off Hayman Island in Queensland.

An inquest into her death began in Queensland on Tuesday.

It was told diving instructor Fiona McTavish took an alternative route to make sure her group did not becoming entwined with a another tour.

During the dive, she looked away to gather her bearings and looked back, but Miss Farrell had disappeared.

Guidelines state during introductory dives instructors are supposed to remain within reach of divers.

Ms McTavish told the inquest: “I turned that corner away from the certified divers, so that’s when I did a roll to see where I was going, so I didn’t hit any of the coral.

“And that’s when I turned back and could no longer see Bethany.”

The instructor said she then took Miss Farrell’s pal, Melissa Clark, to the surface and then spent an hour searching before spotting the former Gilberd schoolgirl on the seafloor at a depth of 50 feet.

Investigators now know Miss Farrell had made it to the surface before drowning. At the time, local divers described the water conditions as “terrible” with a visibility if about six-feet.

Phillip Brown, a crew member of the other tour group, told the inquest he had spotted Miss Farrell at the surface, waving in distress.

He said she was “trying to grasp for air”.

Miss Farrell’s dive computer is said to have shown she may have been at the surface for up to 40 seconds before losing buoyancy.

The 23-year-old’s parents, Patrick and Caron Farrell, previously of Bergholt Road, Colchester, have had to fight for the inquest to be held.

They believe their daughter’s death was “completely avoidable” and told the Gazette “no stone will be left unturned in our fight for truth and justice for Bethany”.

After Bethany’s death, it emerged Wings Diving Adventures deleted photos of the 23-year-old which could have been used by police as evidence.

Central Queensland Coroner David O’Connell’s examination began on Tuesday and was expected to conclude before the end of the week.