Airports are wasting billions of pounds on unnecessary security checks for travellers who pose no threat to planes, according to the airline industry's global body, amid growing support for an airport screening regime that gives preferential treatment to low-risk passengers.

The International Air Transport Association, whose members include British Airways, Virgin Atlantic and more than 200 global airlines, said main airports were struggling to cope with mounting layers of safety regulations that now cost the financially troubled industry $7.4bn (£4.6bn) a year to implement. Tony Tyler, director general of IATA, said: "We spend a huge amount of resource on screening people who quite frankly do not need it.

"We need to find a better way of doing it. Apart from the cost, we are putting our customers through an immensely complicated and, most of the time, unnecessary, hassle. And airports are creaking at the seams to find the space and capacity to deal with this," he added.

Tyler backed a programme being developed by the US Transportation Security Administration, where low-risk passengers could be given less stringent checks if they supplied information including frequent flyer details and travel records. He added that governments should pay for aviation security, not airports, airlines and ultimately passengers. A big manufacturer of airport screening equipment, the UK-based Smiths Group, has seen annual revenue from its detection gear business rise after 9/11 from about £130m to £574m last year – an indication of the costs that have been passed on to passengers. "Aviation security is a matter of national security and state security," said Tyler. "It is not something that airlines should have to pay for. Businesses don't pay for police on the streets, the cost is met by general government revenue. Yet for some reason aviation is singled out to pay for security against threats that have nothing to do with aviation but more to do with powerful geopolitical forces."

BAA, Britain's largest airport owner, believes that September 11 launched a new trend in terrorism but it was a later plot – the failed liquid bomb attacks in 2006 – that changed aviation security most radically. Ian Hutcheson, BAA's head of security, said: "9/11 enhanced the risks from suicide terrorism within the global aviation industry. However, it was the liquid bombs plot in 2006 that had a greater impact on aviation security in the UK and Europe."

The attempted liquid bomb attacks prompted the introduction of limits on liquids in hand luggage and, in the short term, a complete ban on all carry-on bags. Hutcheson added that airport security needed to become less predictable because, as the liquid bomb attempts showed, terrorists remained fixated with attacking airlines.

"It is clear that the terrorist is not deterred from planning and carrying out these types of attack. This is partly due to the fact that some of the things we do are predictable and our challenge now is to identify different ways of delivering security."

In anticipation of changes to airport security being considered by the UK government and Brussels, this month BAA has launched a trial of state-of-the-art bodyscanners that, it hopes, will ultimately remove the need for metal detectors and full body searches at airports. Specially trained BAA staff are also using "behavioural detection" techniques to single out passengers behaving suspiciously who could be referred to the police or immigration authorities.

The post 9/11 crackdown has imposed multi-million pound security costs on UK airports and airlines alone, but the losses in terms of passenger revenues and the impact on US tourism runs into billions, according to experts. Tyler says global airlines suffered three "lost" years in the wake of the attacks, with passenger numbers not returning to 2000 levels until 2003. Revenues also slumped over the same period, with annual turnover not exceeding the 2000 level until 2004.

Strong profitability remains elusive, however, and the industry has made a multi-billion dollar loss in seven of the last 11 years. This year it expects to make a profit of $4bn but that represents a global profit margin of just 0.7%, with much of the industry's financial strength drawn from low-cost carriers.

Nonetheless, the industry is in comparatively stronger financial health than it was in 2002 when it reported a net loss of $11.3bn. (High oil prices caused a $16bn loss in 2008). The aftermath of the attacks saw some carriers sunk by the slump in traditionally profitable business-class and long-haul travel, with the likes of Swissair and Sabena going bankrupt. US carriers were hit the hardest and have made a collective annual profit only three times since 2000. The 9/11 attacks became a reckoning for the US carriers' bloated business models. Between December 2002 and October 2005 some of the biggest names in US aviation - United, Delta, Northwest and US Airways - filed for Chapter 11 bankruptcy protection, which allows businesses to refinance unpayable debts and overhaul inefficient cost bases. However, low-cost airlines such as Ryanair and easyJet have thrived as they bought hundreds of aircraft at cut-price rates and sated the public's desire for cheap short-haul trips, regardless of time-consuming security checks.

"The desire to travel for all kinds of purposes has turned out to be a basic human need," said Douglas McNeill, analyst at Charles Stanley Securities. Global airline passenger numbers have risen from 1.8 billion in 2000 to an estimated 2.8 billion this year, showing that despite the travails of security and fuel costs the airline can at least rely on strong demand. McNeill added: "The risks have been mitigated pretty effectively by new security measures, although they have not worked perfectly. There has been the odd close call on the way, such as the shoebomber and the freight packages that originated from Yemen [in 2010].

"But overall the security systems achieved what they set out to do. The day after 9/11 it was far from clear that the airline industry could withstand the terrorist threat, but it has."

Rail operators also believe they have benefited, with Eurostar now the dominant player in the rail/air market between London and Paris and Brussels, and Virgin Trains and the east coast mainline also seeing a rising share in the London-to-Scotland rail market. "While better performance has been a key element in growth, undoubtedly the airport security issues have also been a key factor," said a Virgin Trains spokesman.

Nicolas Petrovic, Eurostar's chief executive, said: "The combination of ease, convenience and a speedy check-in process means that travellers are increasingly opting for high-speed rail over plane."

Some key markets for US tourism have yet to recover, however. The number of trips to the US by British and Japanese tourists has not recovered to pre-2001 levels, according to Euromonitor, a consumer research specialist. However, total international tourism to the US has recovered to pre-2001 levels, although that took until 2007. Euromonitor adds that stringent security checks including demands for pre-flight information have reduced the appeal of the US to foreign travellers, cutting its share of the market.

"These increased security measures have deterred some visitors and others have complained about how difficult it is to get a visa. These factors have contributed to a decline in arrivals share. The US accounted for 7.3% of global arrivals in 1999, which fell to 6.2% in 2010," said Michelle Grant, Euromonitor's travel and tourism research manager. In some areas at least, and with Asia now the engine for global economic growth, the US may never recover.