Tuning of the performance of a space vehicle is also possible. This allowed for a lighter space vehicle design. The company also designed a unique complex consisting of ejection seat for Buran space vehicle. Generally, ISS flight controllers take a prophylactic approach to space vehicle operations. The reentry problem of a space vehicle was extensively studied. Similar phenomena can cause pogo oscillation and can result in structural failure of space vehicle. Ullage motors were developed for the Saturn V Space Vehicle. The Valkyrie's lightweight construction could also be applied to a wide variety of space vehicle. The name "Dream Chaser" had been previously used for two separate space vehicle concepts. It was the only part of the Apollo/Saturn space vehicle that returned to Earth intact. Gordon and Kelvin begin prepping a smaller space vehicle called "Athena" to escape. SVNs are "space vehicle numbers" which are serial numbers assigned to each GPS satellite.