FLORENCE (AFP) - Disgraced skipper Francesco Schettino on Thursday (April 28) began his battle to avoid prison for the 2012 cruise ship disaster off Italy in which 32 people died, his lawyers arguing that others should shoulder the blame.

Schettino was sentenced in February 2015 to 16 years and one month in jail after a judge ruled his recklessness caused the accident that ensued after the giant Costa Concordia struck underwater rocks off the Tuscan island of Giglio.

The 55-year-old career seaman, who has not yet begun his sentence, says he has been made the solitary scapegoat for the disaster and will seek to overturn his manslaughter conviction in an appeal which opened on Thursday and will run through May at least.

The prosecution is simultaneously appealing last year's sentence, maintaining that Schettino should have been given 26 years.

"We believe there are serious responsibilities not ascribable to Schettino and we hope to be able to show that," lawyer Saverio Senese told journalists outside the court in the Tuscan city.

"The investigation must be deepened. We believe certain probes into technical evidence have been omitted or gave unsatisfactory results (at the first trial). We need to look more deeply... to find what really caused the accident."

During his first, 19-month, trial, Schettino was accused of showing off when he steered the ship too close to the island and of being distracted because he was entertaining a nightclub dancer.

He was convicted of multiple manslaughter, causing a maritime accident and of leaving his boat before all passengers and crew had been evacuated, in breach of centuries-old sailors' code.

He was dubbed "Captain Coward" by the international media while prosecutors branded him "an idiot".

Schettino was given 10 years for manslaughter, five for causing a disaster that led to the biggest salvage operation in maritime history, and one for abandoning ship before all the passengers and crew had been evacuated.

His lawyers insist the accident and its deadly impact had been primarily due to a failure of organisation for which Costa Crociere, its Indonesian helmsman and the Italian coastguard should share the blame.

"We cannot say the blame lies with others. It also lies with others, but that does not clear Schettino," prosecutor Alessandro Leopizzi told the court.

But lawyers for survivors insisted the ship's owner, Costa Crociere, had escaped lightly to date.

"Justice has begun to be served, but there is something important missing from the dock; the society behind Schettino's acts," lawyer Massimiliano Gabrielli said as he arrived in court.

The judges in Schettino's first trial ruled that the company must share civil responsibility for the disaster with the disgraced skipper.

Their compensation awards, totalling just over seven million euros ($8 million), were limited.

The company sidestepped potential criminal charges in 2013 by accepting partial responsibility and agreeing to pay a 1 million euro fine.

Five of its employees received non-custodial sentences after concluding plea bargains early in the investigation.

They included the ship's Indonesian helmsman, who could have averted the disaster but did not understand an order given by Schettino to change course just before the collision.

Awards of 300,000 euros each for the region of Tuscany and the island of Giglio were a tiny fraction of what they were seeking for damage done to the sea bed and tourism.

Survivors of the disaster who had rejected Costa's initial compensation offer and become civil parties in the Schettino case were awarded an average of 30,000 euros.

Civil parties lawyer Massimiliano Gabrielli said they would "of course ask for more money, and continue to ask for justice. We also want the question of responsibility to be widened, notably concerning Costa Crociere".

Among those awarded a payout were Ms Domnica Cemortan, the blonde Moldovan dancer with whom Schettino had dinner just before the ship hit the rocks.

On top of the prison term, Schettino was banned from public office from life and from working as a ship captain for five years.