Overall, an estimated 400,000 passengers were affected because of the alerts. It has been estimated that the first day of delays cost the airlines over £175 million. As many as 20,000 bags are believed to have been misplaced at Heathrow. A 2022 article offers an assessment of the impact of Operation Overt and refers to Rashid Rauf's alleged role.
Flight cancellations All international inbound flights to
London Heathrow Airport were cancelled on the day of the arrests except those already en route. Some flights to and from
London Gatwick Airport were also suspended. Later on that evening, some flights had resumed; shorter flights were resumed around 6pm. However, passengers boarding planes were told they could only carry boarding passes and passports. All other belongings were to be checked in with the rest of their luggage. , 14 August. Erected to give people a place to stay while waiting for their flight to depart A few hours after the beginning of the confusion, aircraft began to fly out of London Heathrow, although in reduced numbers. The situation remained chaotic, with long queues of passengers waiting to check in and get through the strengthened security procedures. Some aircraft were reportedly leaving Heathrow with only transit (i.e., connecting passengers hence already screened elsewhere though not for the limit on hand luggage) passengers aboard. On Sunday, 13 August, 30% of flights out of Heathrow were cancelled to reduce pressure on screeners. By 15 August, flight cancellations had fallen to 47 flights at Heathrow, and 8 Ryanair flights from Stansted. It was reported by BA that 10,000 items of baggage belonging to their passengers had gone missing. It was anticipated that cancellations would reduce on 16 August, with 90% of flights expected to depart as scheduled.
Controversy over the alert On 12 August, a public argument broke out between
BAA, the operator of Heathrow and other airports, and
British Airways, with
Willie Walsh, BA's chief executive, accusing BAA of not being able to cope with the increased security and baggage checks.
Ryanair also called on the British government to employ police and military reservists to speed up the full body searches which were now mandated. Three days later, on 12 August,
BAA ordered airlines using the airport to make a 30% reduction in departing passenger flights (something BA was already having to do, as many passengers missed flights due to the extra time it took to clear security), to help reduce delays and cancellations. On 18 August, Ryanair's CEO,
Michael O'Leary delivered an ultimatum to the British government, demanding the resumption of normal hand baggage dimensions and hand screening one passenger in four instead of one in two within one week, otherwise Ryanair would sue the government for compensation under section 93 of the
Transport Act 2000. The government responded that the actions were taken under the Aviation Security Act 1982, and no compensation was payable. Several pilots complained about the "ridiculous" luggage restrictions that were thought up by "utter morons". Carolyn Evans, head of flight safety at the British Airline Pilots Association, said that "the procedures put in place are not sustainable long-term, and unless the passengers are treated more reasonably, we will not have an industry left". and for using it to drive through unpopular reforms.
Economic effects The Times commented on the day after the arrests that the economic effects were minor. It observed that the real commercial risk is that "people may stop travelling ... because they are tired of complying with necessary security measures."
British Airways cancelled 1,280 flights, at an estimated cost of £40 million.
Ryanair had to cancel 500 flights at an estimated cost of £3.3 million.
EasyJet had to cancel 469 flights, at a cost of about £4 million. BAA said the alert cost them £13 million. In November 2006, BA also claimed the increased security measures since August had cost it £100 million. Air passengers also switched to other means of travel, including ferries operating from Dover to Calais, and
Eurostar. On 13 August 2006, Michael O'Leary, chief executive of Ryanair, claimed that the chaos at airports meant that the terrorists were achieving their aims. ==Trials and sentencing==