Scout X-1


Scout X-1 was an American expendable launch system and sounding rocket which was flown seven times between August 1960 and October 1961. Four orbital and three suborbital launches were made, with four of the launches resulting in failures.

Scout X-1
Scout X-1 with Explorer 9 Feb 16 1961.JPG
Launch of Explorer 9 on a Scout X-1
FunctionExpendable launch system
Sounding rocket
Country of originUnited States
Height25 m (82 ft)
Diameter1.01 m (3 ft 4 in)
Mass16,240 kg (35,800 lb)
Associated rockets
Derivative workScout X-1A
Blue Scout I
Blue Scout II
Launch history
Launch sitesWallops LA-3
Total launches7
First flight1960-07-02
Last flight1961-10-19
First stage – Algol 1B
Powered by1 solid
Maximum thrust471 kN (106,000 lbf)
Specific impulse236 seconds
Burn time40 seconds
Second stage – Castor 1A
Powered by1 solid
Maximum thrust286 kN (64,000 lbf)
Specific impulse247 seconds
Burn time27 seconds
Third stage – Antares 1A
Powered by1 X-254
Maximum thrust60 kN (13,000 lbf)
Specific impulse256 seconds
Burn time39 seconds
Fourth stage – Altair 1A
Powered by1 X-248A
Maximum thrust14 kN (3,100 lbf)
Specific impulse255 seconds
Burn time40 seconds

The Scout X-1 was similar to the Scout X test vehicle which was launched in April 1960, however it had live second and fourth stages, as opposed to the battleship versions used on the Scout X. It also featured an improved first stage, using an Algol 1B instead of the earlier Algol 1A used on the Scout X.

All seven launches occurred from Launch Area 3 at the Wallops Flight Facility. The maiden flight was a suborbital test of the rocket's systems, and was conducted successfully on 2 July 1960, with the rocket launching at 00:04 GMT. Following this, a suborbital radiation experiment was successfully launched on 4 October 1960. The first orbital launch attempt, with the S-56 satellite, was made on 4 December 1960, and ended in failure after the second stage malfunctioned.

On 16 February 1961, a Scout X-1 successfully placed Explorer 9, a reflight of the failed S-56, into Earth orbit, in the first successful orbital launch to be conducted by a Scout rocket. The next launch attempt on 30 June 1961 carried the S-55 satellite, but this did not reach orbit because the third stage failed to ignite. A reflight of S-55, Explorer 13, was launched on 25 August 1961, but reached a lower than planned orbit, and was unusable. The final flight of the Scout X-1 was made on 19 October 1961, carrying plasma and aeronomy research payloads on a suborbital trajectory. This launch was successful.

Several derivatives of the Scout X-1 were also flown. The United States Navy developed the Blue Scout, which was a three-stage sounding rocket, and the Blue Scout II which was almost identical to the Scout X-1. The Scout X-1A, a five-stage variant of the Scout X-1, was used for a single suborbital launch in March 1962. It featured an improved first stage, and a NOTS-17 upper stage.


  • Wade, Mark. "Scout". Encyclopedia Astronautica. Archived from the original on 17 September 2008. Retrieved 19 June 2009.
  • Krebs, Gunter. "Scout". Gunter's Space Page. Retrieved 19 June 2009.
  • McDowell, Jonathan. "Scout". Orbital & Suborbital Launch Database. Jonathan's Space Report. Retrieved 19 June 2009.
  • Heyman, Jos; Parsch, Andreas (9 July 2007). "LTV SLV-1 Scout". Appendix 3: Space Vehicles. Directory of U.S. Military Rockets and Missiles. Retrieved 19 June 2009.