Boeing and Airbus are preparing to pump the world aviation market with billions of dollars worth of loans to carriers in 2009 to try to offset what is expected to be “a very, very tough” year for aircraft manufacturers.

In an interview with The Times, Giovanni Bisignani, the head of the International Air Transport Association (IATA), said that aircraft manufacturers are already trying to set up financial packages in anticipation of a forecast slump in aircraft orders and deliveries.

Industry sources have also confirmed that the big two manufacturers are braced to try to buoy their customers to avoid taking the brunt of a collapse in orders.

While airlines are being forced to slash capacity and cut costs, they are also having to cope with the withdrawal of funding lines from lenders engulfed by the credit crisis.

Iata, whose members represent 93per cent of scheduled international air traffic, has cautioned that the world airline industry is facing the worst revenue crisis since the end of the Second World War and that only US carriers, which rapidly cut capacity before airlines elsewhere, would make a profit in 2009.

Mr Bisignani gave a warning that the global airline industry was already hampered by a large amount of debt, owing a combined $190 billon (£127 billion): “In this climate it is not going to be easy to fund their needs to buy new planes. It is going to be very, very tough for those large players.”

While the aircraft manufacturers insist that they are well-covered in the event of a serious economic decline because they have an order book backlog that stretches up to five years into the future, aviation experts are sceptical.

Chris Tarry, a leading aviation consultant, said: “The manufacturers have been in denial. They have hoped that if they tell everyone it's OK out there, then everyone will think it is and keep buying, but realisation is looming. Both Airbus and Boeing each have between 800 and 900 planes on their order books, many of which the carriers are not going to be able to take. The market has been exceptionally difficult since June, and exceedingly difficult since September.

“It is not a question of fuel any more. It's a question of a global economic downturn. What is happening now is what happens in every slump. Because of the lead and lag times for deliveries, there is far too much equipment about to be delivered as we enter the downturn and someone has to take the risk.”

The gloomy predictions come within a week of an announcement by China's Civil Aviation Administration urging its own carriers either to cancel or to reschedule a number of new aircraft that they are due to take delivery of next year. Chinese carriers have hundreds of plane orders from both Airbus and Boeing and both manufacturers had high expectations of the country, believing that it would be a bigger buyer of new aircraft than any other region over the next 20 years.

The airline industry is also struggling to cope with a sharp decline in freight revenue with air cargo down 7.9 per cent in October alone. Such a drop is likely to raise questions over the future of Boeing's freight orders with its new 777 freighter and for its 747-8 freighter, which is being developed.

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