Four Navy sailors court-martialled for alleged rape with a rubber chicken

Four sailors are on trial for raping a colleague with a rubber chicken during a brutal bastardisation ritual aboard a naval ship.

Able seamen Rohan Angre, Mitchell Summers, Michael Thompson and Jonathan Walter are accused of holding the man down, smearing him with the liniment Deep Heat and Vegemite before assaulting him with the object.

The court heard the attack is alleged to have happened in August 2011 on board the HMAS Newcastle, off the coast of Western Australia.

It is alleged after sexually assaulting the man with what's believed to be a rubber chicken, Able Seaman Thompson tried to push the object into the man's mouth.

"It was at this point he was released for the time being," Prosecuting officer Lieutenant Colonel David Jordan said in Sydney's General Court Martial on Tuesday.

"He was lifted by his arms and legs to the shower station ... He'll tell you his eyes were watering," he said.

"I anticipate he will tell you he saw AB Walter, Angre and Thompson."

The court martial heard he was then placed on his knees and doused with a dark liquid that caused his eyes to blister.

He was then doused with water and left at the bottom of the shower, with burns from the Deep Heat on his neck, shoulders and genitals.

He washed and cleaned himself to go on watch later that night.

The four men face six charges between them, including indecent and sexual assault.

Able seaman Angre has already pleaded guilty to assault occasioning bodily harm.

The court martial continues.