Lockheed Martin has dangled the possibility of final assembly of the F-35 Joint Strike Fighter in front of Japan as part of its plan to win the country's F-X fighter competition.
The US airframer confirmed that final assembly and check out, component manufacture, and F-35 maintenance, repair and overhaul have been included in its response to Tokyo's request for proposals.
"These key fifth-generation production technologies are state-of-the art for the aerospace industry, and will provide Japan with a cornerstone for building long-term industrial leadership," said Lockheed.
Industrial participation is an important component of the requirement, which is to replace the Japan Air Self-Defense Force's fleet of McDonnell Douglas/Mitsubishi Heavy Industries F-4 Phantoms.
Flightglobal's MiliCAS database lists Japan as having an active fleet of 90 F-4s, including 14 reconnaissance-configured examples.
Japan's first preference was to buy the Lockheed F-22 Raptor, but that has not been possible because of restrictions imposed by the US Congress on exports of the fifth-generation fighter's stealth technology.
Industry sources believe this has pushed the F-35 slightly ahead, even though programme delays have some in Tokyo worried.
That would open the competition up to the other contenders - Boeing's F/A-18E/F Super Hornet Block II and Eurofighter's Typhoon.
Boeing sees Japan as the second possible export customer for the Block II Super Hornet after Australia, which itself purchased the F/A-18 as a stop-gap because of concerns over delays to the F-35.
Boeing is touting the F/A-18's multi-role capabilities as a potential discriminator in the contest, citing the Super Hornet's "proven operational capability to seamlessly conduct air dominance or precision strike missions across the combined air, ground, maritime and electronic battlespace".
The rivals, it adds, specialise in "either air-to-air or air-to-ground operations".
Taking a thinly-veiled swipe at the F-35, Boeing Japan president Mike Denton said that when its proposal was submitted, the company provided Tokyo with "guaranteed pricing and a guaranteed delivery timeline".
BAE Systems, which is leading the Eurofighter consortium's campaign, said its aircraft was a "cost-effective" solution and "the most capable deterrent to regional threats". It is also offering Tokyo licensed production, maintenance and technology transfer. The last issue is important to some officials in Japan, who worry about the US willingness to give full access to the F-35's source codes.
"Japan can have sovereign control of manufacture, support and upgrade of Typhoon aircraft in Japan by Japanese industry," BAE said.
"We are also able to offer software source codes and other data, giving Japan the ability to develop the aircraft itself to meet its own unique needs, now and in the future."