velocity (delta-v) of at least 10 ft/s (3 m/s). It was also tested during flight STS-92 when astronauts Peter Wisoff and Michael López-Alegría performed test maneuvers, flying up to 50 feet (15 m) while remaining tethered to the spacecraft. Complications The left side latch on the SAFER unit became unlatched during an EVA by astronaut Piers Sellers on STS-121 while testing shuttle repair techniques. The latch had been inadvertently bumped and moved to the unlatch position. As a precaution, Mike Fossum tethered it to him and the spacewalk continued. In subsequent spacewalks, the latches were secured with Kapton tape, a space-rated form of adhesive tape, to prevent the latches from inadvertently opening. See also Single-person spacecraft References External links Video of SAFER being attached Human spaceflight Extravehicular activity