The chief executive of troubled Scottish airline Loganair is to step down.

Stewart Adams said he was leaving for "personal reasons" and will remain in the job until April.

The regional airline has faced criticism in recent months over the punctuality and safety of its flights.

Mr Adams said: "It has been a great privilege to lead such an important organisation and its fantastic staff for the past three years.

"The widespread improvement initiatives we launched last year are already having a positive impact and our strong financial performance in recent years has also made possible the largest investment programme in the company's history.

"For personal reasons the time is now right for me to step down and I am confident that the strong foundations which have been laid will help enable the new chief executive to continue the company's expansion and growth."

The British Airline Pilots Association made a series of claims relating to the safety of Loganair's aircraft last year, including allegations some were "unserviceable" and planes had "defects that clearly affect flight safety".

Within days, two Loganair aircraft bound for Scottish airports were forced to make emergency landings and a third was found to have a cracked propeller moments before take-off.

The company recently announced a £15m investment programme, which includes £4m for the purchase of two new planes and a £6m investment in a new facility in Glasgow to improve the speed repairs can be made to its fleet.

Loganair operates on 31 routes across the UK, including lifeline routes to the Highlands and Islands.

The airline recently reported that 77% of its flights depart within 15 minutes of their scheduled time - above the UK average.