The 20 unmanned flights used Little Joe, Redstone, and Atlas launch vehicles. They were used to develop the launch vehicles, launch escape system, spacecraft and tracking network. One flight of a Scout rocket attempted to launch a specialized satellite equipped with Mercury communications components for testing the ground tracking network, but the booster failed soon after liftoff. The Little Joe program used seven airframes for eight flights, of which three were successful. The second Little Joe flight was named Little Joe 6, because it was inserted into the program after the first 5 airframes had been allocated.
| Mission | Launch (DD-MM-YYYY) |
Duration | Purpose | Result |
|---|---|---|---|---|
Mercury-Little-Joe 1 |
21-08-1959 |
20 sec |
Test of launch escape system during flight. |
Failure |
Mercury-Big-Joe 1 |
09-09-1959 |
13 min |
Test of heat shield and Atlas/spacecraft interface. |
Partial success |
Mercury-Little-Joe 6 |
04-10-1959 |
5 min |
Test of spacecraft aerodynamics and integrity. |
Partial success |
Mercury-Little-Joe 1A |
04-11-1959 |
8 min |
Test of launch escape system during flight with boiler plate capsule. |
Partial success |
Mercury-Little-Joe 2 |
04-12-1959 |
11 min |
Escape system test with primate at high altitude. |
Success |
Mercury-Little-Joe 1B |
21-01-1960 |
8 min |
Maximum-q abort and escape test with primate with boiler plate capsule. |
Success |
Mercury Beach Abort 1 |
09-05-1960 |
1 min 16 sec |
Test of the off-the-pad abort system. |
Success |
Mercury-Atlas 1 |
29-07-1960 |
3 min |
Test of spacecraft / Atlas combination. |
Failure |
Mercury-Little-Joe 5 |
08-11-1960 |
2 min |
First Little Joe escape system test with a production spacecraft, at max-q. |
Failure |
Mercury-Redstone 1 |
21-11-1960 |
2 sec |
Qualification of spacecraft / Redstone combination. |
Failure |
Mercury-Redstone 1A |
12-12-1960 |
15 min |
Qualification of spacecraft / Redstone combination. |
Success |
Mercury-Redstone 2 |
31-01-1961 |
15 min |
Qualification of spacecraft with chimpanzee named Ham. |
Success |
Mercury-Atlas 2 |
21-02-1961 |
17 min |
Qualified Mercury/Atlas interface. |
Success |
Mercury-Little-Joe 5A |
18-03-1961 |
23 min |
Second test of escape system with a production Mercury spacecraft. |
Partial success |
Mercury-Redstone BD |
24-03-1961 |
8 min |
Final Redstone test flight. |
Success |
Mercury-Atlas 3 |
25-04-1961 |
7 min |
Orbital flight with robot astronaut. |
Failure |
Mercury-Little-Joe 5B |
28-04-1961 |
5 min |
Third test of escape system with a production spacecraft. |
Success |
Mercury-Atlas 4 |
13-09-1961 |
1 h 49 min |
Test of environmental control system with robot astronaut in orbit. |
Success |
Mercury-Scout 1 |
01-11-1961 |
43 sec |
Special satellite to test Mercury tracking network. |
Failure |
Mercury-Atlas 5 |
29-11-1961 |
3 h 20 min |
Test of environmental control system in orbit with chimpanzee named Enos. |
Success |