Thor-Able
| Thor-Able on display at the Air Force Space & Missile Museum | |
| Function | Expendable launch system | 
|---|---|
| Manufacturer | Douglas/Aerojet | 
| Country of origin | United States | 
| Size | |
| Height | 26.9 metres (88 ft) – 27.8 metres (91 ft) | 
| Diameter | 2.44 metres (8 ft 0 in) | 
| Mass | 51,608 kilograms (113,776 lb) | 
| Stages | 2–3 | 
| Capacity | |
| Payload to 640km LEO | |
| Mass | 120 kilograms (260 lb) | 
| Associated rockets | |
| Family | Thor | 
| Derivative work | Thor-Ablestar Delta | 
| Comparable | Luna | 
| Launch history | |
| Launch sites | LC-17A, Canaveral | 
| Total launches | 9 suborbital 7 orbital | 
| Success(es) | 7 suborbital 3 orbital | 
| Failure(s) | 2 suborbital 4 orbital | 
| First flight | 24 April 1958 | 
| Last flight | 1 April 1960 | 
| Carries passengers or cargo | Pioneer Transit Tiros | 
| First stage – Thor | |
| Powered by | 1 LR79-7 | 
| Maximum thrust | 758.71 kilonewtons (170,560 lbf) | 
| Specific impulse | 282 seconds (2.77 km/s) | 
| Burn time | 165 seconds | 
| Propellant | RP-1/LOX | 
| Second stage – Able | |
| Powered by | 1 AJ-10 | 
| Maximum thrust | 34.69 kilonewtons (7,800 lbf) | 
| Specific impulse | 270 seconds (2.6 km/s) | 
| Burn time | 115 seconds | 
| Propellant | HNO3/UDMH | 
| Third stage (optional) – Altair | |
| Powered by | 1 X-248 | 
| Maximum thrust | 12.45 kilonewtons (2,800 lbf) | 
| Specific impulse | 256 seconds (2.51 km/s) | 
| Burn time | 38 seconds | 
| Propellant | Solid | 
The Thor-Able was an American expendable launch system used for a series of re-entry vehicle tests and spacecraft launches between 1958 and 1960.
It was a two-stage rocket, consisting of a Thor IRBM as a first stage and a Vanguard-derived Able second stage. For satellite or space probe launches, an Altair solid rocket motor was added as a third stage. It was a member of the Thor family and an early predecessor of the Delta.
The Able upper stage name represents its place as the first in the series, from the Joint Army/Navy Phonetic Alphabet.