Security staff at Dundee Airport began a 48-hour walkout, forcing it to close its doors.
Flybe Dundee to London Stansted flights will not resume until the industrial action ends at noon on Thursday.
Private aviation and the flight school, as well as air traffic control and emergency services remain operational.
Security staff at Highlands and Islands Airports Limited premises across Scotland have gone on strike over pay and conditions.
On Tuesday, 120 AMSL staff walked out.
Colin Browne of the Prospect union said 14 security staff at Dundee have walked out.
He said: “We don’t want to be on strike, we’re losing pay and especially in this climate that can be difficult to sustain.
“We want Dundee to be busy, we want the airport to succeed and for a lot of us it took some soul searching to come to the decision to take strike action.”