The Kazakhstani Air Astana Embraer E190 had taken off a short while earlier, from the OGMA technical centre in Alverca, near Lisbon, where it had been undergoing “heavy maintenance”, according to tweets from the airline’s President and CEO Peter Foster.
Shortly after the incident, Foster tweeted: “The flight, carrying our technical personnel on its return from heavy maintenance at OGMA, developed serious control problems and was escorted to Beja. Thankfully our technical personnel now safe”.
The OGMA in Alveca is an authorised maintenance centre for Embraer.
The aircraft was positioning as a ferry flight, meaning there were no passengers onboard, en-route to Minsk in Belarus, manned by a crew of six, made up of pilots and engineers.
The plane lost its instruments while in Lisbon’s congested airspace, declared an emergency, and diverted to Beja where it made a safe landing after pilots had battled for two hours to regain some control.
The pilots had discussed the possibility of ditching in the Tagus River or in the sea, but that option was reportedly scrapped due to weather conditions.
A source told Lusa News Agency that, with time, some of the instruments that had been lost were regained, allowing the crew to divert to Beja.
Flight KZR 1388 was escorted for much of the drama by two F-16 fighter jets belonging to the Portuguese Air Force, which guided the plane to the seldom-used Alentejo airport.
The Air Force later published a 50-second video of the aircraft finally landing in Beja, on its third attempt.
Fighter jets are generally only scrambled to aid civilian aircraft in extreme circumstances, like when a plane is in severe difficulties. In circumstances involving instrument failure, which prevents pilots from obtaining accurate readings regarding such as altitude and speed, the fighter jets flying alongside can provide that vital information.
A statement from Air Astana, issued on Monday, confirmed early indications are that problems with the control axes caused the emergency landing, explaining the “aircraft had deviations of stability of the roll-axis”.
Aircraft monitoring site Flightradar shows how the Embraer erratically flew over Lisbon and vicinity while attempting to burn off fuel, before heading towards the Alentejo former air base.
Two crew members involved in the incident required hospital treatment, reportedly for stress-related ailments.
Twenty-four hours later, fighter jets were again dispatched to assist another plane in difficulties, making the rare event of being scrambled twice in as many days.
A Transavia plane was forced to make an emergency landing at Faro Airport on Monday lunchtime, after experiencing pressurisation problems over the Atlantic.
The flight was en-route from Funchal, Madeira, to Amsterdam, with 149 passengers onboard when the issues occurred.
It later emerged this was due to a tail-strike on take-off from Funchal’s Cristiano Ronaldo airport.
A pair of Portuguese F-16 fighter jets were scrambled to escort the passenger jet into Faro, after it declared an emergency shortly after taking off from Funchal, on Madeira island, the air force announced.
The plane, a 737 Boeing flying under the flag of Netherlands airline Transavia, reported pressurisation problems en-route to Amsterdam, the Portuguese Air Force confirmed in a statement.
The aircraft “diverted and landed safely at Faro airport”, at 12.51pm, said the air force, which added that on receiving the alert, it activated “its entire primary search and rescue system” as the situation unfolded.
The F-16 jets are on permanent standby at No.5 air base at Monte Real, near Lisbon, to escort civilian aircraft in difficulties.