Chicago ? The Boeing Co. executive whose affair with CEO Harry Stonecipher led to his ouster last week has voluntarily resigned, the company said Friday.

The woman’s resignation was effective Thursday, spokesman John Dern said. He declined further comment, and the aircraft manufacturer continued its refusal to identify her, citing privacy concerns.

Stonecipher resigned at the request of Boeing’s board of directors for what Chairman Lew Platt said was unprofessional conduct related to the affair. Company sources have said the ouster was necessary because of graphic e-mail exchanges between the CEO and the female executive at a time when Boeing’s ethical conduct was under heavy scrutiny.

The woman was identified last week by BusinessWeek Online, The Wall Street Journal and The New York Times as Debra Peabody, a 48-year-old divorcee who managed office operations for Boeing in Washington.