Please explain in the area below why an STA is necessary:
This STA is necessary for command, tracking, and analysis of the Boeing CST-100 Crew Capsule Orbital Flight Test 2 (OFT-2) mission to the International Space Station. OFT-2 will be Boeings second Orbital Flight Test mission. On OFT-1, which launched in December 2019, Starliner suffered multiple issues, and was not able to meet up with the International Space Station and landed after circling Earth solo for three days. The OFT-2 will repeat all of the same test objectives. The following attached flight timeline was based on the previous launch date of July 7th 2021 and represents Boeing’s current flight plan for its May 20th 2022 attempt.
The docking duration is based on both test objectives and vehicle consumables, and is currently planned to be 3 to 5 days. Boeing/NASA will assess an needs to extend the duration of this mission based on weather or safety concerns.
The program has assigned White Sands Space Harbor (WSSH) as the primary landing site, and Dugway as a backup site.
Space to Ground Communications Concept of Operations:
The S/G communications segment consists of the communications links between the CST-100 and TDRSS. Mission Planning is responsible for determining when communication coverage is possible, based upon CST-100 trajectory and orientation, and determining desired communication contact periods. TDRSS will be the primary communications link to the CST-100 throughout most of the mission (where ever there is positive link margin). The S/G communication links are full duplex data links providing digital voice, low rate imagery, telemetry and command and control capability. The CST-100 automated antenna management software, implemented within the Systems Management flight software, will be used to autonomously select the optimal S/G transmit/receive antenna pair based on the vehicle’s attitude, the target state vector, antenna radiation patterns, and TDRSS or ground station communications coverage schedule. The S/G communications system will be powered off approximately 1 hour after landing.
Space to Space Communications Concept of Operations
The S/S communications segment consists of the direct communications links between the CST-100 and the ISS for rendezvous, docking and undocking mission phases. The S/S communications segment provides full duplex data transfers and digital voice at the appropriate data rates when within communication range of the ISS. The direct communications links allow the CST-100 to navigate within the control sphere surrounding the ISS while maintaining positive control and a safe environment for both spacecraft. For ISS missions, the CST-100 will communicate with the ISS through the NASA Common Communications for Visiting Vehicles (C2V2) system and can be used a “bent pipe” relay for vehicle telemetry from the CST-100 to the MCC-CST.
Included are two files labeled mcCycle_0001.out, the of which covers the vehicle trajectory from launch to docking, whereas the smaller file covers undocking to landing. The three file is the PFD/PSD analysis for the two communications systems.
|