Starliner Airbags
When Boeing’s Starliner capsule comes home from space, it does not splash into the ocean. Instead, it touches down on solid desert ground, cushioned by six large airbags that inflate in the final seconds before landing.
Quick facts
- What it is: A landing-cushion system of six inflatable airbags on Boeing’s CST-100 Starliner crew capsule (the pressurized cabin that carries astronauts).
- Made by: ILC Dover of Frederica, Delaware, the same company famous for spacesuits.
- How many: Six airbags per capsule.
- Where they sit: Underneath the capsule’s base heat shield (the protective layer that shields it from reentry heat).
- What fills them: Compressed nitrogen and oxygen gas, not the explosive charge used in car airbags.
- Reuse goal: Helps a single capsule fly up to about 10 times.
- Landing zones: The western U.S. desert, such as White Sands Space Harbor, New Mexico.
What it is and how it works
Starliner is the first American-built orbital crew spacecraft designed to land on solid ground and be reused, rather than parachuting into the sea. The airbags are what make a ground touchdown gentle enough for people.
The landing happens in a careful sequence. As the capsule falls back through the atmosphere, drag and its heat shield slow it down through the fiery part of reentry. Lower in the sky, parachutes open: two drogue (small, early-deploying) chutes followed by three main parachutes, bringing the capsule to a survivable speed.
At about 5,000 feet (1,500 meters) altitude, the base heat shield is released and falls away. This uncovers the six airbags packed underneath. In less than about two minutes before touchdown, they fill with stored nitrogen and oxygen gas, forming a ring of cushions beneath the capsule. When Starliner reaches the ground, it settles onto these bags, which compress and vent (let gas escape in a controlled way) to soak up the impact, like a stunt performer landing on an air mattress instead of bare pavement. The six-bag arrangement also keeps the capsule roughly upright and steady even if it drifts or tilts slightly at touchdown.
Why it matters
The airbags are what let Starliner land on dry land in the continental United States, instead of splashing into the ocean like Apollo, SpaceX Dragon, or Orion. Avoiding saltwater means no corrosion damage and no costly ocean-recovery fleet, which supports the goal of reusing each capsule up to about 10 times with faster turnaround between flights.
This makes Starliner more like Russia’s Soyuz capsule, which also lands on land. Soyuz fires solid retro-rockets just above the ground for its final braking; Starliner uses airbags instead. The airbags are simpler at the instant of touchdown, but they depend on the heat shield separating cleanly and the bags inflating on time, a crew-critical sequence that happens only once with no second chance.
The system is safety-critical and crew-rated, meaning it must work both in a normal landing and in an emergency abort, including coming down on water, where the same airbags cushion the splashdown and help the capsule float. Boeing chose gas-filled bags rather than car-style explosive inflators because they are gentler and avoid combustion byproducts near the crew.
Testing and notable flights
Before anyone flew, NASA and Boeing tested the design extensively. At NASA’s Langley Research Center, engineers dropped the capsule into a 20-foot-deep Hydro Impact Basin (a water-impact test pool) on February 9, 2016, performed drops from about 30 feet at varied angles and speeds, and ran roughly 30 seat-and-occupant drop tests in different orientations to check how a crew would be protected.
- Orbital Flight Test (December 2019): Starliner deployed its three main parachutes and six airbags and settled gently onto its airbags at White Sands on December 22, 2019, the first land touchdown of an American orbital crew capsule.
- OFT-2 (May 2022): The uncrewed re-do flight reached the International Space Station and again landed on its airbags at White Sands.
- Crew Flight Test return (September 7, 2024): Starliner returned uncrewed and touched down on its six nitrogen-filled airbags at White Sands, while astronauts Butch Wilmore and Suni Williams stayed aboard the station.
