Flight International provides some relatively new details about the performance of SpaceShipTwo, based on comments made by Virgin Galactic president Will Whitehorn and Scaled Composites’ Brian Binnie at a space tourism forum in London last week. According to the report, SS2 will fly to an altitude of 140 km and experience 7 g’s on reentry. However, the “shuddering” experienced by SS1 during the end of its engine burn–caused by the intermittent injection of nitrous oxide oxidizer as the tank neared depletion–may still exist in SS2 because of “its slim design margins”. (The article does note that SS2 will use a “new hybrid rocket motor”, which is not surprising given both that SS2 will be larger than SS1 and the deteriorated relationship between Scaled Composites and SpaceDev, which built the hybrid motors used by SS1.)

The 7-g reentry is a little surprising, because that’s a lot of acceleration to expose tourists to, although that’s probably not avoidable given the higher altitudes SS2 will fly to. That will make the development of seats that can protect passengers from the worst accelerations all the more important. One odd point at the end of the article: the increased downrange of SS2 “could enable it to land at Roswell instead of the New Mexico South West Regional Spaceport near Las Cruces.” But why would you want to do that? The purpose of suborbital space tourism is not to go from point A to point B, but to go from point A to point A via space. Landing at another airport only increases logistical complexities and costs.