
Designation: BCES (Boeing Crew Escape Suit)
Boeing's lighter-than-ACES suit worn by Butch Wilmore and Suni Williams on the 9-month-long unplanned ISS stay.
The Boeing Blue pressure suit is Boeing's IVA suit for the CST-100 Starliner, manufactured by David Clark Company using advanced textile materials. At approximately 9 kg, it is roughly 40% lighter than the Shuttle-era ACES suit. Its defining feature is a soft, integrated helmet hood rather than a separate hard helmet — improving neck mobility and comfort during long Starliner mission profiles. Boeing Blue uses a PROSEAL zipper system from YKK Americas for airtight pressure retention, and touchscreen-compatible gloves for Starliner's Boeing-designed display interfaces. The suit gained unexpected notoriety when Butch Wilmore and Suni Williams wore it on the June 2024 Crew Flight Test (CFT) mission planned for 8 days — and ended up stranded on the ISS for approximately 9 months due to Starliner thruster failures, ultimately returning home on a SpaceX Dragon.
Butch Wilmore and Suni Williams — 8-day planned mission became ~9-month unplanned ISS stay; they returned on SpaceX Dragon in Feb 2025 wearing OCSS suits
👨🚀 Butch Wilmore, Suni Williams