Simplified Aid for EVA Rescue (SAFER) is a small, self-contained, propulsive backpack system used to provide free-flying mobility for a Space Shuttle or International Space Station (ISS) crewmember during extra-vehicular activity (EVA). SAFER is a small, simplified version of the Manned Maneuvering Unit (MMU) intended for contingency use only.
SAFER is designed to be used as a self-rescue device for a separated EVA crewmember in situations when no vehicles can provide rescue capability. SAFER is worn by every crewmember using an Extravehicular Mobility Unit. SAFER was developed at the Johnson Space Center. SAFER was first flown on STS-64 where an untethered flight test was performed. SAFER weighs approximately 76 lb (34 kg) and can provide a total delta-v of at least 10 ft/s (3 m/s).
