Robert M. Haft, president of Crown Books Corp., which he founded in 1977, has been appointed president and chief operating officer of the firm's parent company, Dart Drug Corp.

Haft, 29, succeeds his father, Herbert H. Haft, 62, whom directors of the Landover-based corporation elected chairman and chief executive officer. The post of chairman is a newly created position.

In other appointments announced yesterday, Charles D. Shipe was named executive vice president and senior operating officer, and Benjamin S. Kovalsky was elected senior vice president of merchandising and president of the Trak Auto division.

A spokesman for Dart said that in his new position as president, Robert Haft will be involved in the total operations and planning of the company and that he will continue as president, for the time being at least, of Crown Books.

Neither of the Hafts could be reached for comment yesterday. A spokesman explained, however, that the elder Haft and directors of the company "felt that it was time for Robert to take on more corporate responsibility" after having worked for the company since 1977.

Robert Haft's appointment makes him one of the youngest executives to head a major national company. He is a graduate of the Wharton School of Finance and was simultaneously awarded an MBA from the Harvard Business School and a Masters degree from Harvard's School of Design.

Dart Drug Corp., which Herbert Haft founded in 1956, has expanded in recent years from a regional drug chain to a diversified national company with more than 200 discount specialty drug, home center, books and auto parts stores.

Crown Books, for example, operates about 100 stores nationwide. Trak Auto operates 36 auto parts stores in the Washington area and seven in Richmond. The company has announced plans to expand to the Los Angeles area next year.

Dart Drug recently reported that net income for the six months ended July 31 (before an extraordinary item) increased 29 percent to $1.54 million (92 cents a share) compared with $1.19 million (72 cents) for the comparable period last year.

Sales for the period were $138.5 million, compared with $131.5 million a year ago.