Related news: British airports start to cap number of flights, Ryanair on strike in Spain

London's Heathrow said it would cap the number of departing passengers at 100,000 a day this summer to try to limit traveller disruption as it struggles to cope with a rebound in demand.

Airlines at Britain's busiest airport have already responded to a government appeal to cut capacity but Heathrow said it needed them to go further.

It said airlines, baggage handlers and the airport could collectively serve 100,000 departing passengers, a number that had regularly been exceeded in recent weeks resulting in unacceptable levels of service.

"Some airlines have taken significant action, but others have not, and we believe that further action is needed now to ensure passengers have a safe and reliable journe y," Heathrow CEO John Holland-Kaye said in a open letter to passengers today.

"We have therefore made the difficult decision to introduce a capacity cap with effect from 12 July to 11 September."

"We recognise that this will mean some summer journeys will either be moved to another day, another airport or be cancelled and we apologise to those whose travel plans are affected," he added.

Holland-Kaye said forecasts indicated that even despite the amnesty, daily departing seats over the summer would average 104,000, 4,000 above its cap.

It said on average about 1,500 of these 4,000 daily seats had currently been sold to passengers, and it was asking airlines partners to stop selling summer tickets to limit the impact on passengers .

In the meantime, Spain’s USO (Unión Sindical Obrera) and SITCPLA (Sindicato Independiente de Tripulantes de Cabina de Pasajeros de Líneas Aéreas) unions have called twelve 24-hour stoppages for 1,900 Ryanair cabin crew members at the company’s ten airports in Spain in July. Workers are striking over pay and working conditions.

The six-day Ryanair crew strike will reportedly affect almost 2,650 operations and nearly 400,000 passengers.

Workers are striking in defiance of the Socialist Party (PSOE)-Podemos government’s demand that workers provide “minimum service” of between 57 and 82 percent of flights, depending on the airport and route. Confident of government complicity, Ryanair last month threatened to sack all strikers.

USO called for separate strike days for its easyJet members, who are fighting for similar demands. At EasyJet, Europe’s second budget airline after Ryanair, USO has called for six new strikes on July 15-17 and 29-31 to demand a 40 percent increase in their basic salary.

On only one day, July 15, will Ryanair and easyjet strikes coincide , even though workers are defending the same demands: improved working conditions, higher salaries to offset inflation levels of 10 percent, remuneration for training hours and supplements for seniority.

The combined strength of airline workers at Ryanair and Easyjet was demonstrated last month . The strikes at both companies left at least 241 flights canceled and 1,440 delayed : 26 cancellations and 185 delays at Ryanair, and 215 and 1,255 at EasyJet. Most EasyJet cancellations were to or from Malaga-Costa del Sol airport, but operations at Barcelona-El Prat and Palma's Son Sant Joan airports were also affected.

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