JetBlue Chairman Joel Peterson said McChrystal added "a new dimension to an already strong corps of advisors" at the New York-based airline.
"His reputation for critical thinking and strength in strategy will bring true value to JetBlue," Peterson added.
CEO Dave Barger said McChrystal, 56, would offer "fresh perspectives."
Obama fired McChrystal in July after comments that the general and his aides made about civilian leaders in a profile in Rolling Stone. The magazine dubbed McChrystal "The Runaway General" and quoted him and his aides mocking Vice President Joe Biden and other top administration officials.
Defense Secretary Robert Gates lauded the general during a going-away ceremony at the end of his 3-decade military career, saying it was possible that no American had generated more fear among the nation's violent enemies than McChrystal.
The White House allowed McChrystal to keep his four stars in retirement, although Army rules would have required him to serve another two years at that rank to merit the honor.