Flights out of London began returning to normal on Monday as British Airways said 80 percent of its flights would take off from Heathrow and Britain scaled back a security alert imposed last week after police said they foiled a plot to bomb planes.
BA has cancelled 1,000 flights since last Thursday, when more than 20 people were arrested in what British police said was a plot to blow up airliners in flight between Britain and the United States.
BA said it would again cancel 20 percent of its flights from Heathrow on Tuesday, including 37 short-haul and four long-haul flights.
Delays and cancellations hit airlines on Monday despite airport operator BAA saying it was conducting fewer passenger searches by hand and taking other steps to speed up operations.
"BAA is looking to introduce these changes as quickly as possible over the next 24 hours," it said in a news release. BA said it would again cancel 20 percent of flights from Heathrow on Tuesday, including 37 short-haul and four long-haul flights.
The airports operator cautioned travellers heading for London's Heathrow or Gatwick airports not to bring carry-on bags, despite the Department of Transport on Monday revoking an outright ban on carry-on luggage which it had imposed last Thursday.
BAA said it would be ready to accept carry-on bags on Tuesday but underscored new rules would limit such luggage to a single bag the size of an attache case.
Travellers can again carry mobile phones, laptops and other electronics on board but a ban remained on all liquids in carry-on luggage except prescription medicines and baby food.
Passengers can buy drinks or toiletries once they clear security, BAA said, but not those heading for the United States where a total ban on liquids remained.
"You will not be permitted to take any liquid or gel items purchased in the departures lounge into the aircraft cabin," BAA told US-bound travellers.
All hand luggage would be X-rayed and all passengers boarding flights for the United States faced additional searches at departure gates, BAA said.
"Flights that do operate remain subject to delays," British Airways said in a statement as the eased security measures still remained stricter than those in place before Thursday.
BA cancelled 39 of a planned 202 short-haul flights from Heathrow on Monday and five of its scheduled 76 long-haul flights.
Some 26 BA domestic flights out of London's Gatwick Airport were cancelled on Monday but all flights to Europe and beyond are expected to operate, it said. The airline said it would cancel 11 domestic flights from Gatwick on Tuesday.
Budget carriers Ryanair and easyJet also warned passengers of cancellations, including some inbound flights.
Ryanair Chief Executive Michael O'Leary said the revised security measures were still "nonsensical and ineffective", saying air travel should return to normal.
European train operator Eurostar said it had seen a 27 percent increase in passengers since the introduction of tougher airport security restrictions across Europe, carrying an extra 28,000 travellers over the last four days.
Analysts said last week disruptions could cost BA up to GBP40 million pounds (USD$76 million), similar to what the airline lost last year when baggage handlers at Heathrow went on strike.
Budget carriers such as Ryanair and easyJet rely on rapid turn-around times at airports to maximize profits and delays since last Thursday have slowed operations for all carriers.
