After astronaut Gus Grissom's first flight into space, the hatch on his spacecraft accidentally blew off while Grissom was waiting for a rescue helicopter to fish the capsule out of the ocean, causing the capsule to fill with water and sink and Grissom to nearly drown. The hatch system was re-designed in later spacecraft to prevent similar accidents, and, while training for his third spaceflight, a fire broke out inside Grissom's spacecraft, causing Grissom and two other astronauts to suffocate. The hatch redesign triggered by the accident with Grissom's first spacecraft, meant to help save astronaut's lives, prevented Grissom from being rescued in the subsequent fire accident.