NASA needs to make sure astronauts are safe aboard commercial spacecraft. Retired Vice Adm. Joseph Dyer, the Aerospace Safety Advisory Panel chairman, said NASA's plan has holes. He said the cart is ahead of the horse. Companies are designing space vehicles before NASA sets the safety requirements and certification process. He predicted NASA would have challenges in certifying private aircraft as safe enough. Dyer spoke before a House committee last week. Chairman Ralph Hall (R-Texas) questioned NASA's acquisition strategy. He suggested that funding it would be a risky proposition. NASA wants to send astronauts to the International Space Station on commercial flights within five years.