The Defense Ministry has formally announced the selection of the U.S.-made F-35B cutting-edge stealth fighter jet as part of its plan to acquire short take-off and vertical landing (STOVL) aircraft.

The ministry, which made the decision Friday, plans to renovate the Maritime Self-Defense Force’s Izumo-class helicopter carriers into de facto aircraft carriers to host the F-35Bs.

The government decided last December to procure 42 STOVL aircraft to strengthen the country’s air defense capabilities on its southern islands, where the number of air bases with long runways is limited.

The procurement plan comes amid China’s military buildup and was included in the government’s new defense policy guidelines and medium-term defense program, both compiled late last year.

Selection work started in March, and the F-35B, recommended by the U.S. government, was the only model proposed in the process, according to the ministry.

The F-35B met the required standards in terms of flight capability and stealth performance, a ministry official said.

An F-35A stealth fighter, which does not have vertical take-off capabilities, crashed during a combat exercise on April 9 about 135 kilometers east of Misawa Air Base in Aomori Prefecture. The Defense Ministry said the “spatial disorientation” of the pilot was the cause of the crash.