Little Joe 5B was an unmanned Launch Escape System test of the Mercury spacecraft, conducted as part of the U.S. Mercury program. The mission used production Mercury spacecraft # 14A. The mission was launched April 28, 1961, from Wallops Island, Virginia. The Little Joe 5B flew to an apogee of 2.8 miles (4.5 km) and a range of 9 miles (14 km). The mission lasted 5 minutes 25 seconds. Maximum speed was 1,780 mph (2865 km/h) and acceleration was 10 g (98 m/s²). The mission was a success and Mercury spacecraft # 14A was recovered.
^Loyd S. Swenson Jr., James M. Grimwood, Charles C. Alexander (1966). "10". This New Ocean: A History of Project Mercury - NASA SP-4201. NASA Special Publication-4201 in the NASA History Series. p. 9. Archived from the original on 2009-04-07. Retrieved 26 June 2013.