Adapter (rocketry) explained

In rocketry, an adapter is a hollow cylindrical or conical segment^[1] which provides a sound aerodynamic and structural connection, either between rocket stages (oftern referred to as an interstage) or between a spacecraft and the top rocket stage (referred to as a payload adapter). It may shroud and protect vulnerable systems such as electrics or machinery of rocket engines/spacecraft from weather or noise caused by running engines.^[2] It is discarded during staging.

Examples of rocket stages featuring an interstage adapter:

• Centaur (second stage of several Atlas-based launch vehicles, from Atlas-Centaur to Atlas V)^{[3] [4] [5]}
• S-II and S-IVB (second and third stage of the Saturn V)^{[6] [7]}
• The Interim Cryogenic Propulsion Stage (ICPS) of SLS Block 1 is connected to the Core Stage with the Launch Vehicle Stage Adapter (LVSA)^{[8] [9]}

Examples of rocket stages featuring a payload adapter:

• (Planned) The Exploration Upper Stage (EUS) is expected to connect large secondary co-manifested payloads SLS Block 1B/2 using the Universal Stage Adapter (USA).^[10]

Sources

• Smith . John . Evolved Composite Structures for Atlas V . American Institute of Aeronautics and Astronautics . Reston, Virigina . 2002-07-07 . 10.2514/6.2002-4201 .

Notes and References

1. Book: Wiley J. Larson. Linda K. Pranke. Human Spaceflight: Mission Analysis and Design. 1999. McGraw-Hill. 978-0-07-236811-6.
2. Web site: NASA Continues Progress on Artemis III Rocket Adapter with Key Joint Installation - NASA . 2024-03-07 . en-US.
3. Web site: The Launch of Atlas-Centaur 5 . 2 March 2015.
4. Web site: Centaur - Mission Planners Guide (NASA CR-154970) . General Dynamics Convair Aerospace Division . 1 August 1971. https://web.archive.org/web/20220108213615/http://www.alternatewars.com/BBOW/Boosters/Centaur/1971_Centaur_MPG.pdf . 8 January 2022 . live.
5. Web site: Atlas Launch System Mission Planner's Guide, Atlas V Addendum (AVMPG) . 1 December 1999 . Lockheed Martin.
6. Web site: U.S. Manned Rocket Propulsion Evolution Part 8.20: The Saturn V S-II . McCutcheon, Kimble D. . 3 August 2022.
7. Web site: U.S. Manned Rocket Propulsion Evolution Part 8.30: The Saturn S-IVB Stage. McCutcheon, Kimble D. . 3 August 2022.
8. Web site: NASA's Space Launch System Launch Vehicle Stage Adapter Ready for Thermal Insulation Application . 30 August 2017 . 14 September 2022.
9. Web site: 2021-03-24 . NASA Completes Weld of Rocket Adapter for First Artemis Launch with Crew - NASA . 2024-03-07 . en-US.
10. Web site: Universal Stage Adapter (USA) . 14 September 2022.