Dynalectron Corp., the McLean-based diversified technological services conglomerate, last week announced the appointment of Daniel R. Bannister as chief executive officer.

Bannister, a 32-year veteran of the company and its president since last November, replaces Merlon F. Richards, who has reached the company's mandatory retirement age of 65.

In announcing Richards' retirement, which is effective June 1, Jorge Carnicero, Dynalectron's chairman of the board since 1955, praised him for the role he has played "in making Dynalectron a financially sound, growing company with a great future."

Richards, an accountant, joined the company in 1952 as a financial officer of a key subsidiary, Land-Air Inc., becoming its executive vice president in 1957. Since his appointment to the parent company in 1959, he has played major roles in the firm's development, including chief financial officer, chief operating officer and, most recently, vice chairman and chief executive officer. He will continue as a member of the board of directors.

For at least the last three years, Bannister, 54, has been groomed for the company's top management position. Before his appointment as president in November, he was responsible for the company's Technical Services segment -- the fastest-growing of Dynalectron's two major segments -- as well as corporate finance, administration and strategic planning. Bannister also was elected to the board of directors for a two-year term.

Bannister will be supported in his new role by a top management team that includes, among others, G. Walther Ewalt, a former executive vice president who has been appointed to the post of chief operating officer.

Dynalectron, the 15th-largest public company in the Washington area last year, reported annual revenue of $638.2 million and profits of $12 million. PROFESSIONAL SERVICES

Dewberry & Davis, a Fairfax-based engineering and architecture firm, recently announced appointments: Robert T. Skunda, currently its director of marketing and a recently elected director of the Fairfax County Chamber of Commerce, has been named a principal in the firm. R. Wayne Keeler, formerly a section head with the Washington Suburban Sanitary Commission, has joined the firm as an associate and assistant branch manager of the firm's Gaithersburg office. And Barbara Sowell Cromer, who has been an interior designer and space planner for the past 13 years, has joined the firm as director of interior design in its Fairfax headquarters. COMMUNICATIONS

Jack Clements, executive vice president and general manager of Mutual Broadcasting System, has been named president of the Arlington-based communications company. Clements will have overall responsibility for the company and its two divisions -- Mutual Radio Network and Mutual Satellite Services. Mutual is a division of the Amway Corp. RETAIL, WHOLESALE TRADE

Joseph H. Santarlasci Jr., the Smith Barney, Harris Upham vice president who managed the leveraged buyout of Dart Drug Stores Inc., has been appointed vice chairman of the regional retail chain. Dart Drug Stores was formed last June through a leveraged buyout of the drug-store chain from Dart Group by two senior executives, Alvin F. Towle and Stephen J. Hansbrough. Santarlasci, a director of the company since its inception, joins them as a principal and a member of the management team. In addition, Dart Drug promoted three longtime employes and participants in the buyout, completing the six-member management team: Darryl Bryant to senior vice president for finance, Robert Goldstein to senior vice president for operations and Allen Nehman to senior vice president for merchandising. Dart Drug Stores also promoted Ronald Sanford to the new position of vice president of pharmacy administration and named Robert Berry and Harland S. Stockwell assistant vice presidents at the Landover-based company.

MBI/Math Box has tapped Kenneth Cleeland for the job of chief financial officer and vice president of finance and administration for the East Coast computer retail chain. Cleeland, a graduate of George Washington University, has been with Price Waterhouse, Head Sportswear, and most recently, J. G. Hook, a mid-Atlantic retail and wholesale firm, as chief financial officer.

Mark M. Murphy, director of public affairs for Figgie International Inc., will leave the diversified Richmond firm in June to become vice president for corporate communications at Best Products Inc., a Richmond retailer and catalogue showroom operator with annual revenue about three times that of Figgie. Murphy fills a vacancy created by the resignation of Edwin J. Slipek Jr. in January. TRANSPORTATION

Hanne Merriman, president of Garfinckel's, was elected a director of USAir Group Inc. and USAir Inc. at the airline company's recent annual shareholders meeting. INDUSTRIAL, MANUFACTURING

Martin Marietta's Robert G. Morra, a veteran aerospace engineering executive, will leave the company's Denver Aerospace operations for the post of corporate vice president in charge of technical operations in its Bethesda headquarters. Succeeding Morra in Denver will be Warren G. Beery, currently director of technical operations for space launch systems. GOVERNMENT

Virginia's Center for Innovative Technology has named Auzville Jackson an executive consultant to advise on questions of intellectual property, such as patent and copyright law. CIT President Robert H. Pry said clarifying patent and copyright questions is a "crucial element" in developing CIT's research institutes and called Jackson an "ideal candidate" for the job. Jackson is president of AJ Associates Inc., a high-tech consulting firm, and was formerly vice president for technology and patents at Robertshaw Controls Co. He also has taught at the University of Richmond and the College of William and Mary and founded the Virginia State Bar Association's Patent, Trademark and Copyright Section.

The Overseas Private Investment Corp. has named Bruce N. Hatton and C. Dale Duvall vice presidents of the government agency. Hatton, who joined the agency as director of legislative affairs, will head the newly formed market development and communications department. Duvall, an accountant, has been treasurer of OPIC since 1981. In addition, Katherine Camalier, an assistant to former White House Chief of Staff James A. Baker III for four years, will supervise information resources within the new communications department. BANKING AND FINANCIAL SERVICES

Wenifred O. Pearce, executive director of the Virginia Bankers Association from 1971 to 1983 and president of Banking Consultants of America since then, has been named president of the Hampton Roads region of First American Banks of Virginia, which operates 27 offices in the area.

Heritage International Bank, a two-year-old Bethesda bank, has named William A. Delphos, president of Health Communications Inc. and founder of Venture Marketing Corp., to its board of directors. Delphos was senior vice president of the Overseas Private Investment Corp. from 1981 to 1985.

Washington Federal Savings & Loan Association has elected Gerald E. Hansen president and chief executive officer of its Silver Spring subsidiary, Washington Permanent Insurance Agency. He was formerly with Allstate Insurance Co.

Century National Bank President Joseph S. Bracewell has been elected to the additional post of chairman of the board, succeeding Charles Emmet Lucey. Bracewell, a former president of the Solar Energy and Energy Conservation Bank under the Carter administration, has been president of Century National since its inception in 1982. The bank's board also elected John R. Cope, a partner in the firm Bracewell & Patterson, as vice chairman; William H. Isaac, an independent real estate developer, as secretary to the board, and Rosemary M. DeMark as recording secretary.