After soaring into the wild blue yonder with its production of automobiles and electronic gadgetry in the 1970s, Japan is preparing to Launch itself into the upper echelons of the world aircraft industry in the 1990s.

With strong government backing, Japan's industrial giants are actively pooling their technological know-how and securing the massive financing needed for a takeoff into commercial aircraft production.

Recently, the Japanese have demonstrated their flair for manship and reliability in making major components for Boeing's new 767. Now moving toward a larger stake in the development of the Seattle-based company's next-generation commercial jetliner, the Japanese are eager to shed their role as a subcontractor to the world's major aircraft producers.

"We've got the technological ability and the resolve to boost the Japanese aircraft industry into the ranks of the world's most advanced aircraft makers," said Eitaro Murai, managing director of the Society of Japanese Aerospace Companies, an industry umbrella group.

Murai, like other industry analysts here, acknowledges that closing the technological gap, while possible, would be costly. But the biggest obstacle, he said, is the absence in Japan of a large enough domestic aircraft market to allow the country to build a strong export base as it did in the case of automobiles and shipbuilding.

In 1981, Japan's fledgling aircraft industry had $1.3 billion in sales -- less than 5 percent of global sales and a fraction of American sales. Its growth has been hampered by its heavy reliance on military contracts from Japan's Defense Agency, although the share of defense-related sales shrunk from 86 percent of total sales in 1979 to 78 percent last year.

If all goes according to plan -- and Murai and others admit it is still something of a big "if" -- the industry is expecting commercial aircraft sales to expand to as much as 50 percent of its business by the early 1990s and, measured at current prices, to top $5 billion.

For nw, Japanese ambitions are welded to plans to take part in what is called here the "YXX" project -- a fuel-saving, 150-seat, short-haul jetliner now on the drawing boards at Boeing, McDonnell Douglas and Airbus Industrie in Durope. All three competitors have courted the Japanese industry to help develop the next-generation aircraft and offset a sizable part of the estimated $2 billion to $3 billion it will take to get the project airborne.

According to industry analysts and government officials, the Japanese have now narrowed the field of potential foreign partners to Boeing and may reach a broad agreement in current talks with the U.S. company by the end of the year, if the powerful Ministry of International Trade and Industry has its way.

Miti, the watchdog of big business interests in Japan, virtually has elevated the YXX deal to the level of a nationalproject because of what officials view as its long-range implications for the development of new strategic industries that will provide the cutting edge for the country's technologically sophisticated economy in the years ahead.

"If Japan fails to realize this project," said Akira Yamazaki, assistant director to Miti's aircraft and weapons division, "we will have missed an opportunity to develop our technology in the field of large [commercial] aircraft for the next 20 to 30 years."

Typically, Miti is exerting strong influence behind the scenes to organize Japanese aircraft makers for the YXX project. Under its wing, Mitsubishi Heavy Industries, Kawasaki Heavy Industries and Fuji Heavy Industries, agreed to underwrite 15 percent of the costs in developing Boeing's 767. Under the terms of the agreement, the role of the Japanese companies, which now pursue aircraft production only as a sideline, is largely restricted to producing the fuselage and other components for the new jetliner.

Next time, however, the same Japanese companies are demanding an expanded role that would involve them in all phases of the YXX, including design, sales and after-sales servicing. MITI, which is of fering substantial government subsidies to participants in the project, also wants to get Japan's giant trading houses into the act by using their global business network to help develop the sales and marketing apparatus for aircraft that Japan now lacks.

Talks are now believed to be stuck on Boeing's demand for the Japanese to shoulder 30 percent of the cost of developing the new jetliner while the Japanese are insisting on a smaller financial stake of between 20 and 25 percent. U.S. industry observers in Tokyo also suggested that it may prove difficult to include the Japanese in aircraft sales and servicing because of Boeing's dominance in those areas.

In a bid to spread the financial risks more evenly among a large number of key companies, MITI has asked Nissan Motors, Japan's number two automaker, to participate in the venture. Nissan said last month that it had entered a broad agreement with Martin Marietta Corp. of the United States to obtain basic technology for the development of aerospace and defense-related equipment.

Following that announcement, Nissan's president, Takashi Ishihara, indicated that the company is now contemplating the leap into commercial aircraft production in line with efforts to diversify its business. Nissan officials, however, declined to elaborate on the company's plans.

Major U.S. aircraft makers are not worried yet about Japan emerging as a serious rival any time soon. Willard A. Hughes, managing director of Boeing's Japan-based operations, said, however, "If government and industry were to make the commitment, I see no reason why [the Japanese] couldn't develop a competitive industry in aircraft just as they have done in other fields."

Reflecting the widely accepted view in the industry here that participation with foreign partners is now the key step, a consortium of three Japanese companies launched a joint project three years ago with Rolls-Royce of Britain for the development of a fuel-saving, low-noise jet engine designed for use in a next-generation passenger jet of the YXX type.

In another international link, Kawasaki Heavy Industries is putting the finishing touches on a multipurpose helicopter in collaboration with Messerschmitt Boelkow Blohm of West Germany