Two lawmakers have proposed legislation to make permanent the ban on smoking on airline flights of two hours or less.

The law will expire in 1990 unless Congress votes to extend it or make the ban permanent, as Reps. Dick Durbin, D-Ill., and Bill Young, R-Fla., have proposed. They were the original sponsors of the measure first passed in 1987."The American flying public not only has accepted this smoking ban, they welcomed it," the two said in a joint statement. "Experience shows the law has worked extraordinarily well. This is a sensible regulation that has helped improve the health and safety of every airline passenger. It should be permanently extended."

The smoking ban covers about 80 percent of domestic flights. Violations can bring a fine of up to $1,000, and tampering with an aircraft smoke detector can result in a $2,000 penalty.

Durbin and Young cited Federal Aviation Administration figures showing that in the first four months of the law, there had been just 18 enforcement actions, almost all involving smoking in aircraft rest-rooms where smoking has long been forbidden because of fire dangers.