Federal investigators say planes like the American Eagle that crashed in Indiana last week should be temporarily barred from flying in conditions that could cause steering mechanism icing. This development follows mounting evidence that the plane rolled out of control while on autopilot in just such conditions. The FAA has already barred crews of the ATR-72 -- the model of the American Eagle plane -- and of the similar ATR-42 from using the automatic pilot in icing conditions. But in a letter yesterday the government's National Transportation Safety Board urged the FAA to take the planes out of service until further analysis is done. About 30 of the ATR planes are in the air in the U.S and a total of 130 planes, manufactured by the French-Italian consortium Avions de Transport Regional, are in service worldwide.Post your opinion on theScience & Technologybulletin board.