COLOGNE, Germany ― Sikorsky has teamed up with Rheinmetall Defence in an upcoming competition to replace Germany’s fleet of heavy-lift transport helicopters, the companies announced Tuesday.

Sikorsky, which is part of Lockheed Martin, is offering the CH-53K King Stallion to replace the German military’s aging fleet of CH-53G helicopters. The old helicopters are due to be retired in the mid-2020s.

Berlin wants to buy between 45 and 60 new aircraft in a deal expected to cost billions of dollars.

An industry day is set for Feb. 28 in Koblenz, where the government will release details of its acquisition plan. A formal solicitation to industry is expected later this year.

Besides Sikorsky’s offering, Boeing’s C-47 Chinook is a contender for the program, known in Germany as “Schwerer Transporthubschrauber.” The aerospace giant released a whitepaper last fall illustrating its German roots going back to Wilhelm Böing, the immigrant father of the company’s founder, William E. Boeing.

The two U.S. companies have an interest in giving their offerings a German face, following local industry concerns last year that the government would buy existing vehicles from across the Atlantic without considering domestic participation.

The German defense company will provide maintenance, support and training, while the Lockheed Martin subsidiary would supply the hardware.

Additional companies are expected to join the cooperation, according to a statement by Sikorsky.

A Defence Ministry spokesman said the government is still in the process of evaluating the pros and cons of each aircraft, such as external and internal cargo transport.

The CH-53K King Stallion, which had its maiden flight in October 2015, is expected to achieve initial operational capability for the U.S. Marine Corps in 2019.