BAA has warned that the capacity constraints at Heathrow are tighter than ever, restricting growth in the UK economy.

The warning came as BAA announced that its airports served 108.5m passengers last year, an increase of 4.4%.

After adjusting for exceptional events in 2010 such as British Airways strikes, volcanic ash and snow disruption, the underlying increase was 0.9%.

Edinburgh saw record traffic of 9.4m in 2011 beating the previous record set in 2009 (9.0m). Heathrow also saw record passenger figures with 69.4m passengers passing through the airport’s terminals. The previous record was 67.9m set in 2007. Record passenger numbers accompanied record efficiency levels with the average aircraft operating with 75.2% of its seats occupied.

Results in the international ASQ benchmarking survey showed that 70% of passengers across Heathrow rated their experience at the airport as either ‘Excellent’ or ‘very Good’, up from 57% in 2008. Last year represented the best punctuality performance in a decade (a).

There was also a record 476,197 flights, which represent 99.2% of Heathrow’s annual limit of 480,000.

BAA warned that airlines are unable to develop new routes to emerging markets from Heathrow due to capacity constraints, meaning the UK is at risk of falling further behind Europe as continental hubs have been expanding.

BAA Chief Executive, Colin Matthews, said: “As the UK’s only international hub airport, Heathrow is central to developing our trade links with fast-growing emerging markets. Capacity constraints are damaging the UK economy today when the country can least afford it.

“A new hub airport has been proposed in the South East, but this has a projected cost of £50billion and may take decades to build. During this time we would be handing over on a plate the UK’s historic trade advantages to our European competitors.”