CST-100 Starliner

CST-100 Starliner. The CST-100 Starliner is a reusable crew capsule developed by Boeing as part of NASA's Commercial Crew Program. Designed to transport astronauts to and from the International Space Station and other low Earth orbit destinations, it represents a key component of America's renewed capability for domestic human spaceflight. The spacecraft aims to provide routine, cost-effective access to orbit under a fixed-price service contract with NASA.

Overview

The spacecraft's primary mission is to ferry crews to the International Space Station, supplementing and eventually replacing reliance on the Russian Soyuz spacecraft. Under the Commercial Crew Program, Boeing and SpaceX were selected to develop independent transportation systems, with SpaceX's Dragon 2 achieving operational status first. The Starliner capsule is launched atop a United Launch Alliance Atlas V rocket from Cape Canaveral Space Force Station. It is designed for reuse up to ten times, with a service module that is jettisoned and replaced for each mission.

Development and design

Development began after Boeing received a Commercial Crew Transportation Capability contract from NASA in 2014. The design emphasizes automated flight with manual crew override capability and incorporates legacy technology from earlier programs like the Apollo command module and Space Shuttle. Key partners include Aerojet Rocketdyne for propulsion systems and United Launch Alliance for launch services. A significant design feature is its weldless structure, intended to enhance safety and reduce manufacturing complexity. The capsule comprises a crew module for the astronauts and a service module housing propulsion, power, and thermal control systems, which is discarded before re-entry.

Flight history

The program's first uncrewed orbital flight test, Boe-OFT, launched in December 2019 but encountered a mission-elapsed timer anomaly, preventing a planned rendezvous with the International Space Station. A subsequent repeat test, Boe-OFT 2, successfully docked with the station in May 2022. The first crewed test flight, Boe-CFT, carrying NASA astronauts Barry Wilmore and Sunita Williams, launched in June 2024. This mission, designated Starliner-1, docked with the International Space Station but experienced several helium leaks and thruster malfunctions, extending the crew's stay for additional testing. The successful completion of Boe-CFT is a required milestone before the spacecraft can be certified for regular operational missions.

Specifications

The Starliner crew module has a diameter of 4.56 meters and provides 11 cubic meters of pressurized volume. It can accommodate up to seven passengers or a mix of crew and cargo for missions to low Earth orbit. The service module utilizes Aerojet Rocketdyne launch abort and orbital maneuvering engines. The spacecraft is designed for land-based returns, using airbags to cushion touchdown on one of several designated sites in the Western United States, such as White Sands Missile Range. Its nominal mission duration is up to 210 days while docked to a station.

Future missions and program status

Following the crewed test flight certification, NASA has contracted for six operational crew rotation missions to the International Space Station. The first operational mission, Starliner-1, is scheduled for 2025. Program future depends on resolving technical issues identified during Boe-CFT and meeting all NASA certification requirements. Boeing has also marketed the capsule for potential commercial space station visits, such as those planned by Axiom Space or Sierra Space's Orbital Reef. The long-term viability of the program will be evaluated against its operational performance and cost relative to other vehicles in the Commercial Crew Program portfolio.

Category:Spacecraft Category:Human spaceflight