For airlines which have had a strong grip on the rich transatlantic flight pipelines to and from London Heathrow airport, old routines will be dislocated.

The company with most to lose is British Airways. One of the airlines with most to gain is Air France-KLM.

For newcomers now able to gain access, competition will be tough and will focus on gilt-edged business passengers who can expect improved services and comfort, analysts say.

'Fares will fall, but moderately by six to ten per cent,' forecast Didier Brechemier, a consultant for Roland Berger experts in Paris. But the reduction would affect only flights from Heathrow where interest in the effects of the new agreement is focused.

Until now the only airlines offering flights from Heathrow to the United States were British Airways and Virgin Atlantic and the US companies United and American Airlines Heathrow is the key piece on the European chess board of flights to the United States because of long-established factors, including language, and the rise of London as the biggest centre of world finance.

The Heathrow hub for British Airway flights has also acted to a degree as a collection point for European transatlantic traffic: the open skies arrangement could open this up and possibly open out other European hubs.

'British Airways (BA) faces two dangers: the decline of Heathrow as a hub for transit passengers and the appearance of new carriers on transatlantic routes,' said Mr Brechemier.

The new rules are likely to benefit members of the Sky team alliance such as Air France-KLM which will now be able to fly from Heathrow to the United States. In October, the French airline and US carrier Delta created a joint company for this purpose with the intention of including US airline Northwest.

Another airline set to benefit is BMI of Britain, a small carrier which holds 11 per cent of the landing rights at Heathrow, the second-biggest allocation after the BA slots.

The agreement has pushed up the value of these rights and BMI might sell some of them and even launch its own transatlantic flights. The German airline Lufthansa owns 30 per cent of BMI.

At Hypovereinsbank analyst Uwe Weinreich said: 'I expect it to acquire another 50 per cent in 2009.' Lufthansa could try to expand its operations via BMI, but it already has access to Heathrow via the Star Alliance and United Airlines, and Weinreich did not expect it to launch new routes immediately.

At French brokers Oddo Securities, Yan Derocles forecast: 'Heathrow is likely to see the arrival of many new operators.' An additional factor is that flights from Heathrow were about 15 per cent higher than transatlantic fares from other big European airports.

But he doubted that there would be a big impact elsewhere in Europe. 'For the other airports we foresee almost no effect unless a new competitor is particularly aggressive, and we see no sign of this for the moment,' Mr Derocles said.

An all-out fare war seems unlikely because the Heathrow routes to the United States are already in strong competition and traffic has been slowing for 12 months because of strains in the US economy. More generally, fuel costs have soared.

'And when you look at the margins of the airlines, you can see that they could do better than launch a fare war,' Mr Brechemier observed.

Passengers should benefit from an increased range of flight times but the agreement would probably not lead to many new routes because of poor prospects for profits, the analysts said.

One class of passenger certain to benefit will be so-called 'premium' business travellers from Heathrow to the United States.

A British analyst, who declined to be named, said that the airlines would fight for premium traffic. BA offered hourly flights to New York, he said. If competitors wanted to win customers, they would have to offer lower prices.

The premium business drives profitability. If you don't have premium passengers, it's not even worth launching a route. Heathrow has three times more premium passengers than the other airports,' Mr Derocles explained.

The quality of comfort and services offered to business passengers is also likely to improve.

'They will travel on newer aircraft, which is not altogether the case with British Airways. They will have cabins which have been refurbished with new seats, and improved frequent-flyer programmes,' said the British expert.

'The quality of services provided will improve. The premium passenger should gain,' said Mr Brechmier. -- AFP