number of recent fatal accidents. let s go to our homeland security correspondent, jeanne meserve. she has the details. reporter: wolf, too many life-saving medevac helicopters have been costing lives because of crashes. today, proposals intended to make them sever. the irony is never lost, helicopters designed to save lives instead crashing and taking lives. four died in this 2008 crash of a medevac hell had copter just outside washington, one of 139 air ambulance crashes in the past ten years that have killed 130 people. these people are out there doing a humanitarian service and they end up losing their lives in the process. to improve safety, the federal aviation administration is now proposing new rules for medevac chopper, requiring ground warning systems, stricter flight time and crew rest rules,