Flybe passengers dependent on the airline to get around the UK and Europe have warned of the impact on their lives if the regional carrier collapses.

At Exeter airport, where Flybe is based, customers expressed concern on Monday that a collapse would leave holes in flight schedules. The airline carries more than 8 million passengers a year and is a key operator at regional airports around the UK, with a network covering 56 airports across Britain and Europe.

Gary Whitham, who uses Flybe to commute to Exeter for work from his home in the Netherlands, said: “I am on a project in Exeter until April and have been since October. I have heard nothing at all about Flybe’s problems. If they do go, then I would have to fly to Bristol, which is much more inconvenient for me.”

On the arrivals board, nine of the 10 flights displayed were operated by Flybe, from destinations including Belfast, Newcastle, Amsterdam and Dublin. Flybe flies to 14 destinations from Exeter.

A man waiting to pick up his daughter-in-law and grandchildren from the airport said: “My son travels every week to Luxembourg from Cornwall for work. But Cornwall is becoming more and more isolated. People in the south-west are fed up with the poor transport links. Billions of pounds are being spent on Crossrail and improving rail links to major cities by a few minutes from London, but down here we have poor rail, road and air routes.”

Malcolm Bell, head of tourism at Visit Cornwall, said air links to the west country, where Flybe also runs services to Newquay, were vital for the region. “It would be terrible if we lost that air link.”

The British Chambers of Commerce (BCC), which represents 75,000 businesses, said Flybe’s domestic network and its links with continental destinations was key for companies around the UK. Adam Marshall, the director general of the BCC, said that maintaining routes was a key demand for businesses across the country.

“Airports are economic engines for many regions of the UK,” he said. “First and foremost they help connect our communities to trading partners in the UK and throughout the world.”

John Strickland, an aviation consultant, said Flybe’s collapse would have “a significant impact in certain communities”. He added: “At a market level, it doesn’t look like very much. But if you look at the regions [Flybe serves], it’s dramatic.”

At Manchester airport, Marcia Pita, 38, said Flybe’s European network was vital for her job. Travelling home to Porto in Portugal, Pita said she was “extremely disappointed” to hear of the airline’s woes. She works remotely for a British oil services company but flies to Aberdeen for meetings and to see friends monthly, using Flybe to get from Portugal to Manchester and then Scotland’s oil capital.

“There’s not really any other way I could feasibly get to work without it that wouldn’t take so many more hours or cost so much more,” said Pita.

George Fildes, 64, an accountant who travels from Manchester to Düsseldorf regularly, said despite the inconvenience it would cause him, the government should not be pressed to prop up the company. “It’s got to stand up on its own two feet. Clearly the model’s wrong,” said the Derbyshire resident. “It’s convenient and cheap, but perhaps that’s part of the problem – maybe it’s a bit too cheap for its own good.”

There were also concerns in Northern Ireland, where on Monday Flybe was running all but five of 37 flights scheduled from George Best Belfast City airport. Business between regions could be particularly affected by any collapse, according to Alan Lowry, the managing director of Environmental Street Furniture, a company based near Belfast that sells items such as park benches and cycle racks and has clients across the UK.

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“It would be exceptionally difficult for us,” he said. “One of the biggest problems in flying out of Northern Ireland [is that] Flybe offers more flights to the UK than any other airline.”

Flybe runs routes to “a lot of the regional places that are really hard to get to”, he said. “For that to be taken away from the business community would be problematic.”

For the Isle of Man, the crown dependency in the Irish Sea, Flybe’s collapse could imperil a crucial service: transporting patients to Liverpool for hospital treatment. About 17,000 journeys to the UK are undertaken each year by Manx residents for hospital appointments.

The Isle of Man government said the airline was operating as normal as of Monday morning, and that it was still booking patients on to Flybe services.