AS SPEC. SHARON COOLEY was going back in time, traveling to a continent where her ancestors had been sold into slavery. ''My first half is American and I know all about the United States; but my second half is African and I hadn't experienced Africa," said Cooley, 27, a preventive medicine specialist with the 71st Medical Det in Grafenwöhr, West Germany.

Traveling to Botswana gave her the chance "to experience the other half of my heritage that I had heard about but never seen."

Other black Americans who were part of the crisis-response team also said the trip to Africa was a once-in-a-lifetime opportunity to gain a better understanding of their African heritage.

''I wanted to come see what the culture was like; to find out exactly where my roots came from," said Spec. Steven Copney, a licensed practical nurse at the Landstuhl medical center.

Both Copney and Cooley learned as much as they could about the country by talking to the people of Botswana, called Batswana. Many of the Batswana spoke English, the official language of the country, as well as their native Setswana.

"I felt at home," Copney said. "it was just a wonderful feeling all through me. I talked to a lot of people about the history, culture, ancestry, and they taught me their language as best they could in a short time."

Cooley found the Batswana to be friendly and "different from the stereotypes I had been fed as a kid. They are into educating themselves; they're very intelligent, progressive people."

Cooley talked to people about the slave trade in Africa and learned that warring African tribes made slaves of the people they conquered, selling them to other tribes or to Arab nations.

Europeans who eventually arrived on the continent bought slaves from Africans as well. But people were not determined slaves by the color of their skin until Americans entered the slave trade, Cooley was told.

Most of the Africans who were sent to the United States as slaves were from the west coast of central Africa. Cooley's father had told her their ancestors were from Nigeria. Copney said he has only been able to trace his ancestors back to Britain, from where they were shipped to the United States as slaves.

Cooley and Copney said they would share their experiences with other people when they returned to West Germany and to the United States.

"I would really like to come back here," Copney said. "I'd like to see all of Africa."

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