The walkout later this month will affect six airports – Inverness, Sumburgh, Kirkwall, Stornoway, Benbecula and Dundee. The Prospect union said the strike was an escalation in its industrial action, which dates back to January, over plans to "centralise air traffic control in Inverness".
Prospect members working for HIAL voted for action at the end of last year, with Prospect accusing HIAL of "removing high-value skilled jobs from economies that can ill-afford to lose them".
HIAL branded the 24-hour walkout "extremely disappointing" and said it came at a crucial time for aviation as it seeks to emerge from the Covid crisis. It called on the union to work with the group on its "modernisation project".
Loganair customers booked to travel on affected flights will be able to transfer their booking without incurring a change fee or having to pay a fare difference to another Loganair flight. This extends to alternative routes, if they wish. They can otherwise request a full refund.
Affected customers will be notified of their options by email on Thursday (15 July) and details on how to manage their booking.
Loganair will put on extra services before and after the proposed industrial action to help people complete their journeys.
There will be extra services on the evening of Wednesday 28 July departing Kirkwall at 7pm, arriving into Aberdeen at 7.50pm, and from Aberdeen to Kirkwall on Friday 30 July departing at 6.10am, arriving into Kirkwall at 7am.
Loganair also plans to operate larger aircraft on several other services on 28 July and 30 July to provide additional seats.
Flights to and from Islay, Barra, Tiree and Campbeltown will be unaffected as the flight information service officers who oversee arrivals and departures at these airports are not part of the dispute, said Loganair.
The airline is also looking into whether it can offer inter-isle services within the Orkneys on 29 July. An update on this will follow.
Jonathan Hinkles, Loganair chief executive, said: “We are hugely disappointed by this strike action by the union representing air traffic controllers at HIAL airports, and can only ask for our customers’ understanding that we are unable to avoid the inconvenience these flight cancellations will inevitably cause to travel plans, hospital appointments and island deliveries."
