Mr Adams was managing director of Aberdeen-based BMI Regional before leaving two years ago to head up Tiger Airways in Singapore. Chief operating officer Phil Preston, who arrived from Calmac Ferries in May 2012, joins Mr Adams on the Loganair board alongside David Harrison, who takes over Mr Grier's role as executive chairman.
Mr Harrison said: "We wanted to find someone who had experience in this sort of small aircraft regional environment and market, but Stewart is someone who has also had some experience elsewhere in the world. For some reason, he wanted to swap the sun of Singapore for the snow of Glasgow."
Mr Grier, 71, announced his retirement last September after 36 years with the business, which celebrated its 50th anniversary last year. He led the 1997 management buy-out which secured the future of Loganair, and sold his majority stake last year to Stephen and Peter Bond, who built up helicopter business Bond. Stephen Bond, who backed the original buy-out and already held just under 50% of the shares in Loganair, is the airline's chairman.
Mr Harrison said Mr Grier would now have "no day-to-day involvement whatsoever" but a purely advisory role. "We needed to bring some more strength into the senior management team."
He said of Loganair, which last year reported a 25% rise in pre-tax profits: "We are a little bit in our own market and not caught up in some of the bigger battles, business continues to be quite good."
Loganair expanded into Norwich last year by taking on a contract from Flybe, and Mr Harrison said they were "always hopeful there might be one or two other opportunities" though nothing was on the horizon.
He said although the Scottish market was seen as subsidised, 90% of Loganair's business was purely commercial.