Workers at Australian state-owned submarine builder ASC Ltd began a four-day strike on Wednesday, escalating a campaign for higher wages that threatens maintenance work on the aging submarine fleet Australia must rely on until its nuclear-powered AUKUS replacements arrive in the 2030s.
The 100-hour strike began at noon on Wednesday and includes all of the roughly 350 blue-collar workers at the Osborne Naval Shipyard in South Australia state, where Australia maintains its fleet of Collins-class submarines, according to the Australian Manufacturing Workers Union (AMWU).
The strikes, the latest in a series since May, are adding months of delays to maintenance work on two of Australia's six Collins submarines, according to the union.
ASC said in a statement it could not comment on submarine availability for national security reasons.
Workers are striking over what they say are discrepancies in pay between those employed by ASC Ltd in South Australia state and Western Australia state.
Unions say the workers in South Australia are paid 17.5% less on average and want ASC Ltd to equalize pay for their workers in the two states.
"Workers are frustrated with the company," said AMWU South Australia Assistant State Secretary Stuart Gordon, who flagged the possibility of more strikes next week.
"ASC has said it would address pay parity and come to the bargaining table. But clearly the company has refused to do either."
ASC said unions had rejected multiple offers and it will continue to negotiate in good faith.
The shipyard is vital part of Australia's naval infrastructure and is where ASC and British firm BAE Systems, will jointly build Australia's fleet of nuclear-powered submarines, the core component of the 2021 AUKUS pact between Australia, Britain and the United States.
Australia announced last month a $1.4 billion dollar, four-year contract with ASC to extend the life of the Collins class submarines until the AUKUS replacements are ready.