With a bad odor hanging over the ruling Liberal Democrats, Japan's latest aircraft bribery scandal, involving a key former defense official and $1.4 million, is coming to a noisy end with no major trials likely.

Months of investigations and political accusation shed new patches of light on the cozy relationship between big business and politics here. For a time, this latest episode seemed destined to become another Lockheed scandal, which led to the indictment of fomer prime minister Kakuei Tanaka in 1976. Once again, a leading member of the Liberal Democratic Party seemed to have been caught taking money covertly in exchange for political clout.

But prosecutors acknowledged this week they could not invoke the bribery law, and opposition leaders in the parliament were having difficulty forcing a vote on a perjury charge against the principal politican allegedly involved.

The key figure in the case is Raizo Matsuno, a prominent Liberal leader and former director-general of the Japanese Defense Agency. He was Japan's top civilian defense minister in the late 1960s and was in a position to influence the choice of a new fighter aircraft, which ultimately became McDonnell-Douglas' F4E Phantom jet.

Prosecutors determined that Nissho-Iwai Co., a principal trading company here, secretly funneled about $1.4 million to Matsuno between 1967, and 1971.

At the time Nissho-Iwai was McDonnell-Douglas' agent in Japan, charged with promoting sales of the Phantom.

Matsuno acknowledged in testimony before a parliamentary committee that he received the money from two high officials of Nissho-Iwai, who asked him not to make any written records of the transactions. He claimed it had been a "political donation" that did not violate any law since Japan at the time had no statue requiring such donations to be publicly disclosed. He did not accept it as a payoff for favors to Nissho-Iwai, he insisted.

His version was partly contradicted by Shigeki Ito, director of the Justice Ministry's criminal affairs bureau, who said the money had been given Matsuno to faciliatate the sale of the Phantoms.

"In view of the overall picture we obtained, we recognize the money as having been given [to Matsuno] for his maneuvers and for his success concerning the F4E," Ito testified. But he said he had no concrete evidence the company asked Matsuno to take specific actions to promote the Phantom.

On other details, Matsuno's memory was vague. He could not remember exactly how many payments he received or exactly what he did with them. He recalled using the money for "election and political campaigns." asked if he had spread the money around to political allies, he replied, "I don't remember."

Opposition parties scoffed at Matsuno's story.

"It is impossible to think that a trading company devoted so much money to this without expecting to get something back," a Socialist member, Makoto Tanabe, said in an interview. "There was a prior promise, between Matsuno and Nissho-Iwai, that the money would be paid in part if he was successful" in promoting the Phantom.

The Socialists and other opposition parties agreed yesterday to demand a full committee meeting to vote on placing perjury charge against Matsuno, using as a basis the conflict between his and Ito's testimony on why the money changed hands.

The Liberal Democrats shows no inclination to go along with a perjury charge. A vice secretary-general of the party, Kabun Muto, observed in an interview that even Ito, the prosecutor, did not believe there was evidence of criminal perjury.

"If the prosecutor cannot indict him we should not accuse him," said Munto.

He said he believed Matsuno accepted the money as recognition of a "long relationship" with Nissho-Iwai, not as a bribe to support the Phantom. There was no political fund reporting law in the late 1960s, he said. Muto acknowledged that it was "difficult" to believe Matsuno could have used such a large amount of money for his own political purposes. He suggested Matsuno may have passed it out to political friends over the course of three elections - a point Matsuno has not acknowledged.

The case, although apparently closed, leaves a cloud of suspicion hanging over the Liberal Democrats, partly because Matsuno was such a prominent party member. His father had been a party chief, and he had been one of five leaders of a faction loyal to former prime minister Eisaku Sato. He also was a leader of the party reform movement that erupted after the Lockheed scandal.

The public reaction has been stern. Newspaper editorials criticized the majority party for failing to pursue the questioning and called for a perjury indictment.

"The party failed to take a stand and, to all appearances, would simply like to hush the matter," said the Yomiuri newspaper in an editorial.

Prime Minister Masayoshi Ohira reacted by establishing a private advisory council to study ways of preventing a repetition of the aircraft scandals, but it has not been greeted with applause.

"We don't think anything will come of this unless the Liberal Democratic Party reflects on its past faults," declared the Yomiuri editorials.