I had a new idea for additional braking on freight trains. most trains probably don't need it but I have heard of some horror stories about braking failures, so it got me thinking, what if you added sails to the sides or top of every freight car that were folded closed against the car and that can be deployed in an emergency much like parachutes on a drag car making the hole train very un-aerodynamic slowing it allot. Anything that can reduce stopping distance for a freight train could, in theory, save lives. There are probably allot of issues with this idea and maybe some better solutions, but I think the idea is interesting, so discuss.