Prime Minister Robert Mugabe departed tonight for an official visit to the United States, leaving unresolved the issue of six white Air Force officers imprisoned despite their recent acquittals on charges that they helped sabotage Zimbabwean airplanes.

His departure caps a week of intense efforts by western diplomats to free the airmen, whose redetention has resulted in bitterness and antagonism between blacks and the white minority. He is to arrive in the United States Saturday.

According to knowledgeable sources, British High Commissioner Martin Ewans met privately with Mugabe Friday seeking the release of the officers, four of whom hold dual citizenship. He also delivered a message from British Prime Minister Margaret Thatcher. American diplomats have also had several sessions with Zimbabwean officials.

But reactions of both nations, which are Zimbabwe's main suppliers of foreign aid, have been muted. Sources said there has been no direct reference to an aid cutoff or reduction in the talks for fear such a threat would only trigger a negative response from the Zimbabweans.

"People here are very sensitive on issues of national sovereignty," said a diplomat, who predicted less understanding in London and Washington if accord is not reached soon.

The Financial Gazette, a white-operated business weekly, said the redetentions "will seriously tarnish Zimbabwe's reputation throughout the world" and "cast a shadow" over Mugabe's visit. It blamed "personal vindictiveness" on the part of Home Affairs Minister Herbert Ushewokunze, who signed the orders redetaining the officers immediately after their acquittal last Wednesday.

Said a white independent lawmaker who requested anonymity, "For those of us who say we agree with much of what the government is doing and who try to be constructive, this will have a devastating effect."

But many blacks are upset with what they see as white hypocrisy on the redetentions, which were often used by the government of former prime minister Ian Smith during the days of white rule. "I find it nauseating when whites who never opened their mouths when thousands of Africans were detained without trial suddenly are so concerned about justice," said Willy D. Musarurwa, editor of the Sunday Mail newspaper, who was detained for nearly 11 years under Smith. Zimbabwe Leader en Route to U.S.; 6 Remain in Jail Despite Acquittals By Glenn Frankel Washington Post Foreign Service

HARARE, Zimbabwe, Sept 7--Prime Minister Robert Mugabe departed tonight for an official visit to the United States, leaving unresolved the issue of six white Air Force officers imprisoned despite their recent acquittals on charges that they helped sabotage Zimbabwean airplanes.

His departure caps a week of intense efforts by western diplomats to free the airmen, whose redetention has resulted in bitterness and antagonism between blacks and the white minority. He is to arrive in the United States Saturday.

According to knowledgeable sources, British High Commissioner Martin Ewans met privately with Mugabe Friday seeking the release of the officers, four of whom hold dual citizenship. He also delivered a message from British Prime Minister Margaret Thatcher. American diplomats have also had several sessions with Zimbabwean officials.

But reactions of both nations, which are Zimbabwe's main suppliers of foreign aid, have been muted. Sources said there has been no direct reference to an aid cutoff or reduction in the talks for fear such a threat would only trigger a negative response from the Zimbabweans.

"People here are very sensitive on issues of national sovereignty," said a diplomat, who predicted less understanding in London and Washington if accord is not reached soon.

The Financial Gazette, a white-operated business weekly, said the redetentions "will seriously tarnish Zimbabwe's reputation throughout the world" and "cast a shadow" over Mugabe's visit. It blamed "personal vindictiveness" on the part of Home Affairs Minister Herbert Ushewokunze, who signed the orders redetaining the officers immediately after their acquittal last Wednesday.

Said a white independent lawmaker who requested anonymity, "For those of us who say we agree with much of what the government is doing and who try to be constructive, this will have a devastating effect."

But many blacks are upset with what they see as white hypocrisy on the redetentions, which were often used by the government of former prime minister Ian Smith during the days of white rule. "I find it nauseating when whites who never opened their mouths when thousands of Africans were detained without trial suddenly are so concerned about justice," said Willy D. Musarurwa, editor of the Sunday Mail newspaper, who was detained for nearly 11 years under Smith.