Boeing has won a contract worth $1.49 billion to build 13 more P-8A maritime surveillance aircraft, and buy titanium and other materials needed for work on 20 further planes in coming years, the Pentagon announced on Thursday.

The contract covers production of nine P-8A aircraft to be built for the U.S. Navy, and four aircraft for the Royal Australian Air Force, the Defense Department said in its daily digest of major weapons contracts.

It also includes funding for titanium and other parts needed for the manufacture of 16 additional P-8A aircraft for the U.S. Navy and four more Australian planes, the department said

“By working together since the early stages of P-8A development, the U.S. and Australia have created one airplane configuration that serves the needs of both countries,” said Capt. Scott Dillon, U.S. Navy P-8 programme manager. “The U.S. and Australian P-8As will be able to operate with each other effectively and affordably for decades to come.”

This latest award puts Boeing on contract to build the Navy’s second lot of full-rate production aircraft, bringing the U.S. Navy’s fleet total to 62 P-8As. Boeing has delivered 28 Poseidons to date.

“Delivering premier aircraft on schedule and on cost has become a hallmark of the P-8 program,” said James Dodd, Boeing vice president and general manager of Mobility, Surveillance and Engagement. “We look forward to building on Boeing’s long-standing relationship with Australia by providing the quality, value and capability of the P-8A.”

The US Navy has deployed the first two P-8A patrol squadrons since operations started in 2013.

Australia’s participation in the P-8 programme began in 2009 when the government signed the first in a series of memorandums of understanding to work with the U.S. Navy on system design and development. The U.S. Navy and the RAAF also established a joint program office that operates at Naval Air Station Patuxent River, Md.

Production of the first Australian P-8A will begin later this year, with delivery to the RAAF scheduled for 2016. Boeing will also provide the RAAF with a complete training system for the P-8A, using simulators to train pilots and mission crews to operate the aircraft, its sensors, communications and weapons systems without relying on costly live flights.