UNC Resources Inc., a diversified minerals and manufacturing conglomerate, announced yesterday that it has appointed a former Pan American World Airways Inc. executive as its new president.

Dan A. Colussy, a 53-year-old former airline, engineering and marketing executive, takes over as UNC president on Jan. 1. Colussy replaces former chief executive Keith A. Cunningham, who retired in July after guiding the company out of serious financial difficulties.

Colussy, a director of UNC since 1981, had been the president of Canadian Pacific Airlines Ltd. since 1982. Prior to that, he worked for Pan American World Airways in various executive posts for 10 years, including three years as president.

UNC faces an array of options stemming from its recent financial turnaround. According to analysts, the company's choices include repurchasing its own stock, buying new businesses, developing or shedding existing operations, or merging with another company.

Colussy said yesterday that it is too early to be specific about changes at UNC.

Colussy said he regards the company, which has headquarters in Falls Church, "as an unusual opportunity and challenge."

Financially troubled only eight months ago, UNC recently has shed some of its weaker operations.

In addition, a $300 million out-of-court settlement capped a nine-year legal battle for control of the company. Under the agreement, Gulf Oil Corp. and its subsidiary, General Atomic Co., paid UNC $130 million in cash and assumed a $71 million obligation to repay about 2.3 million pounds of uranium to Pacific Gas & Electric Co.