The windscreen damage was too severe to risk trying to continue on to Bristol Airport
The plane, which took off from Las Palmas in Gran Canaria on Monday evening, was forced to plunge from 30,000ft to 10,000ft after the pilot noticed damage to the windscreen.
The Thomson flight landed at Porto Airport, where passengers were held while they waited for another flight.
Nobody we've spoken to knows what is going on and that includes the airport staff
One passenger told the Bristol Post: “Our plane from Gran Canaria has made an emergency landing in Portugal.
“The cockpit windscreen was cracked so had to descend from 30,000ft to 10,000ft before making an emergency landing.
“We've been here about two hours now. Everyone is OK but a bit fed up as we are not really being told very much about what is going on other than being shunted from one part of the airport to the other.”
This picture on social media shows the extent of the damage
She added: "Nobody we've spoken to knows what is going on and that includes the airport staff."
Passengers were allegedly only told that the aircraft had suffered a ‘technical fault’ during the flight, and only learned about the windscreen damage once they had landed.
Electronic devices BANNED on flights Fri, March 24, 2017
Britain and America have implemented an electronic device ban on certain flights bound for the US, and Britain. British Airways, EasyJet, Jet2.com, Monarch, Thomas Cook, Thomson are all affected by the ban. Here are the devises currently banned.
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She said: "There were some very nervous looking people but on the whole most people stayed calm. We had realised something was wrong before they announced it due to the sudden descent mid-flight. There was a big clap on landing.
“It was the flight stewards that told us to look at the windscreen when we disembarked.
“Everyone is remarkably upbeat considering.”
The passengers were forced to wait in Porto Airport while arrangements were made to fly them home
The news comes after a plane crashed into a supermarket car park close to the Portuguese capital Lisbon earlier on Monday, leaving five people dead.
The light aircraft, which was carrying four people, is said to have exploded in mid-air and come down near a Lidl supermarket in Tires, landing on a lorry that was unloading.
All four people on board are said to have died, alongside the lorry driver on the ground.