Answers Your Questions
| From: Ron Rogers, of Kansas
To: Tony Ceccacci, flight director for the orbit 2 team
Question: There are three orbit-boost procedures planned for this mission - why not do them all at once, in one big boost?
Answer: Since the orbiter hardware used to perform the reboosts wasn't specifically designed for the types of firing patterns required to perform reboosts, extensive engineering analysis was performed to see how long the hardware could safely be used. Early results showed that a one-hour time period was what the vernier thrusters could support with the duty cycles that were going to take place so reboosts are planned to take place in one-hour time blocks. The three reboosts taking place use different methods. There will be two sessions performed that use the primary RCS plus X thrusters for reboost and one session that only uses the vernier thrusters. The two reboost methods also require a different orbiter orientation and will be taking propellant from different systems.
Orbit 2 Propulsion Officer