An engineering expert, called as a witness by airline attendants suing the tobacco industry, testified yesterday that US airlines rejected design changes that would have eased smoke pollution on airliners but also would have cost airlines billions of dollars.

Mr Paul Halfpenny, an airline ventilation engineer, told jurors hearing a landmark second-hand-smoke trial in Miami that the design changes recommended in Boeing 737 and 747 aircraft would have reduced second-hand cigarette smoke and generally improved air quality.

However, the changes would have required the jets to consume hundreds of thousands of gallons more fuel each year. This would have cost $663 million annually for the US fleet of 737s and more than $1.3 billion for 747s used by American airlines, Halfpenny said.

Halfpenny, who was called by lawyers pressing the $5 billion lawsuit on behalf of some 60,000 non-smoking flight attendants with alleged tobacco-related disorders, had commissioned studies of the proposed ventilation design changes.