The NTSB is downplaying the role icing played in the Feb. 12 crash of a turboprop that killed 50 people as it approached Buffalo, N.Y. The board’s investigation so far has found that the plane would have encountered light or moderate icing, but that would have had a “minimal impact on the stall speed of the airplane.” And the NTSB’s latest update confirms earlier reports that one of the pilots pulled back sharply on the control column when the stick-shaker engaged. The NTSB will hold a hearing in May to review many aspects of the accident. Besides icing and weather, the board is reviewing the flight crew’s actions, training, recent flights and fatigue, as well as looking more broadly at Colgan Air’s training programs and other procedures for pilots.