A man who was captain of a ship that struck an oil tanker more than five years ago has admitted pretending to be a teenager online to have sexual conversations with girls.
Jacob Taverner was sentenced in the Brisbane Supreme Court on Thursday after earlier pleading guilty to a raft of charges committed over nearly a year, including 19 counts of using a carriage service to transmit indecent communication to children under 16.
The court heard the 57-year-old - who had no criminal history - had sexualised conversations with 20 girls aged between 11 and 15 over three months.
He connected with them using a pseudonym on Instagram, adopting the identity of a teenage boy.
Taverner also shared and discussed videos showing child exploitation to nine "presumably like-minded" people in a private chat group, Justice Susan Brown said.
In addition he admitted accessing and storing on his phone nearly 600 examples of child exploitation material, including images of children as young as two being abused by a man.
Taverner's offending was calculated and persistent, with him taking steps - like storing images under a business name - to avoid being detected by his wife of 24 years.
Justice Brown found that his behaviour was "more than an idle curiosity".
The court was told Taverner has had nightmares since the 2015 accident at sea while another man was at the helm of a vessel he was captaining.
The noise of the ship hitting an oil tanker woke Taverner.
No lives were lost but crew members were arrested for going ashore without following proper channels after the vessel - which sustained three holes - was towed to Singapore, the court heard.
Taverner was exonerated "but not really the same afterwards", barrister Rachael Taylor said.
During a downturn in the industry that followed Taverner, then in his mid-50s, was laid off.
Justice Brown said Taverner had offended during a low point in his life after suffering trauma.
But he had no explanation and could not recall a significant part of offending presumably because he was drinking heavily.
"You may not recall some of the offending, Mr Taverner, but you need to own it," Justice Brown told him.
She handed Taverner - who has spent 55 days in custody - an effective sentence of three years and four months behind bars.
Taverner will be eligible to apply for parole on September 12 next year.