In this historical photo from the U.S. space agency, after the hatch "Liberty Bell 7" opened prematurely, gallons of seawater entered the spacecraft. A helicopter recovery team attempted to empty the water, as seen in this photo.
Seconds after this picture was taken on July 21, 1961, the Marine helicopter dropped the spacecraft because it was too heavy to continue lifting, and the capsule sank to the ocean floor. Astronaut Virgil I. Grissom was still in the water at the time, and his head is seen bobbing next to the capsule. Grissom almost drowned, but was rescued by a second helicopter before his suit filled up with too much water.
The Liberty Bell 7 was eventually recovered from 15,000 feet below the surface of the Atlantic on July 20, 1999.
Each weekday, SPACE.com looks back at the history of spaceflight through photos (archive).