The Convair X-11 (originally designated the Convair XSM-16A) was the first testbed for what became the Atlas missile program. Later the Convair X-12 became the second, more advanced testbed for the Atlas program.
A total of 12 X-11's were built and tested. The first three were involved in static tests only. X-11 Number 4 and 6, were destroyed in launch accidents. All others performed successful test flights. The test series began on June 11, 1957 and ended on June 3, 1958.
- Crew: Unmanned
- Length: 96 ft (29.3 m)
- Diameter: 12 ft (3.66 m)
- Empty: 12,500 lb (5,665 kg)
- Loaded: 80,000 lb (36,288 kg)
- Maximum speed: Mach 10.6
- Range: 690 mi (1,111 km)
- Service ceiling: 40 mi (61 km)
- Rate of climb: m/min ( ft/min)
- Wing loading: kg/m² ( lb/ft²)