Word of the accident, which occurred at 4:30 in the afternoon, shattered the jubilant mood in Eagle's crisp, modern headquarters on University Avenue and throughout the area's sprawling computer plants. The concentration of such companies in the area has won it the nickname Silicon Valley, a reference to the silicon chips used in computers.

Mr. Barnhart, a bearded electrical engineer who frequently expressed pride in the management team he had assembled, scored a solid success with the company's first offering of stock to the public. Details of Stock Offering

The 2.75 million shares were offered Wednesday on the over-thecounter market at $13 each. They were snapped up within hours, rising in value to $17 and closing at $15.50. The company would have raised $37 million by issuing the stock, and the value of Mr. Barnhart's 592,000 shares on the market would have been $9 million. Trading in the stock was halted yesterday after news of the crash. With the withdrawal of the stock offering, the company will not realize any money from Wednesday's sales.

Initial public offerings are occasionally rescinded because of poor market conditions, but Eagle's move is unusual in that it was a popular offering that was withdrawn because of a crisis within the company.

Andrew Seybold, who edits a report on computers, said of Mr. Barnhart: ''The organization he built is very solid from a management point of view. His loss will be tremendous, but his company will survive.''

Other sources said Mr. Barnhart had given his executives leeway to make decisions. ''He delegated authority very effectively,'' said John K. Jerrehian, a management consultant in Menlo Park, Calif.

The company's statement said that it ''strongly believes the strength and depth of the management team, which was built under the guidance of Mr. Kappenman and Mr. Barnhart, will enable it to realize the full potential of its position in the rapidly expanding microcomputer market.'' Named President in May 1982