Algol (rocket stage)

{{Infobox rocket

|name=Algol

|manufacturer=Aerojet Rocketdyne

|mass={{convert|1,900|kg|lb}}

|image=File:Scout-D rocket - Smithsonian Air and Space Museum - 2012-05-15 (7246252390) (cropped).jpg

|caption=Scout D-1 rocket that used the Algol rocket stage at the Smithsonian Air and Space Museum, 2012. Algol stage and interstage are visible

|function=Rocket stage

|height={{convert|9.4|m|ft}}

|stagedata=}}

File:Science Museum London 1110592 nevit.jpg. Jet vanes on the nozzle of Algol stage are visible]]

The Algol family of solid-fuel rocket stages and boosters is built by Aerojet (now Aerojet Rocketdyne) and used on a variety of launch vehicles. It was developed by Aerojet from the earlier Jupiter Senior and the Navy Polaris programs.{{Cite book |last=Hammond |first=Walter |title=Space Transportation: A Systems Approach to Analysis and Design |publisher=American Institute of Aeronautics and Astronautics |year=1999 |isbn=978-1-56347-032-5 |location=Reston, VA |doi=10.2514/4.862380}}{{cite web |url=http://www.nasa.gov/centers/langley/news/factsheets/Scout.html |title=Scout Launch Vehicle Program |publisher=NASA}} Upgrades to the Algol motor occurred from 1960 until the retirement of the Scout launch vehicle in 1994.

The Algol family use solid propellant fuel with a loaded mass of 10,705 kg, and produces 470.93 kN of thrust. The motor has a specific Impulse of 236 seconds in a vacuum environment. Variations Algol I, I-D, II, II-A, II-BA popular rating was 40KS-115,000 (52,000 kgf for 40 seconds), also known as Senior.

They were initially developed as the first-stage of propulsion for the Scout rocket, with the design being based on the UGM-27 Polaris, a submarine-launched ballistic missile developed for the United States Navy at the Jet Propulsion Laboratory.{{cite web|url=http://www.gsfc.nasa.gov/gsfc/service/gallery/fact_sheets/general/scout.htm |title=NASA'S SCOUT LAUNCH VEHICLE |publisher=NASA GSFC |url-status=dead |archiveurl=https://web.archive.org/web/20080510104748/http://www.gsfc.nasa.gov/gsfc/service/gallery/fact_sheets/general/scout.htm |archivedate=2008-05-10 }}{{cite web|url=http://www.redstone.army.mil/history/systems/sergeant.html |title=SERGEANT |publisher=Redstone Arsenal |url-status=dead |archiveurl=https://web.archive.org/web/20080612022555/http://www.redstone.army.mil/history/systems/sergeant.html |archivedate=2008-06-12 }}

Algol 1 (XM-68)

; Algol 1 (XM-68)

This rocket design started as the Polaris test motor, 31 feet in length with a {{convert|40|in|m}} diameter steel case, and 86,000 lbf of thrust.

The eventual UGM-27 Polaris A-1 was larger, {{convert|28.5|ft|m}} in length and {{convert|54|in|m}} in diameter.{{cite web|title=Polaris A1|date=May 30, 1997|url=https://nuke.fas.org/guide/usa/slbm/a-1.htm|publisher=Federation of American Scientists|access-date=April 1, 2023}}

The Algol 1 was first used for a successful suborbital launch of a Scout X-1 rocket on September 2, 1960.{{cite web | url = http://www.tbs-satellite.com/tse/online/lanc_scout.html | title = TSE – Scout | publisher = The Satellite Encyclopedia}} The rocket started as a UGM-27 Polaris test motor with a 40-inch diameter, the largest solid motor ever tested at the time. It had a nominal performance rating of 40 seconds duration and 45,000 kgf thrust. It was {{convert|19.42|ft|m}} long, {{convert|2.6|ft|m}} in diameter.{{cite web|title=Algol-1|url=http://www.astronautix.com/a/algol1.html|website=astronautix.com|access-date=April 1, 2023}} Later versions for Scout D scaled to {{convert|1.14|m|in|abbr=on}} in diameter.

; Algol 1-A

Used on the Scout X (Cub Scout) test flight flown April 18, 1960. served as prototype vehicle for eventual Scout rocket.

;Algol 1-B

Used on Scout X-1, RM-89 Blue Scout I, and RM-90 Blue Scout II.

;Algol 1-C

Used on the Scout X-1A. After this single flight, the Scout X-2 with Algol 1-D replaced this prototype.

; Algol 1-D

Used with Scout X-2, Scout X-2M and Little Joe II. Solid rocket stage. 440.00 kN (98,916 lbf) thrust. Mass {{convert|10,700|kg|lb|abbr=on}}.

It was first used on the Scout X-2 on March 29, 1962. It continued to be used on Scout X-2 and Scout X-2M launches (4) until 1963.

Image:Apollo- Little Joe II Liftoff (December 8, 1964) - cropped.jpg

Algol 1-D was first used on the Little Joe II Qualification Test Vehicle in 1963.

May 13, 1964 – Algol Boosts Little Joe II A-001 flight.

An Aerojet-built Algol 1D heavy-duty rocket motor performed successfully for the 36th consecutive time on May 13, 1964, as it carried a NASA Little Joe II spacecraft on the Apollo program A-001 test flight. Averaging 96,650 pounds thrust, the Algol 1D was the largest solid rocket motor flying in non-military space programs. Test hardware on May's successful Apollo test flight included: an unmanned instrumented command module, service module, launch escape system and the Little Joe II launch system.

Algol engine used on Little Joe II

Thrust: 465 kN each

Length: 9.1 m

Diameter: 1 m

Weight full: 10,180 kg

Weight empty: 1,900 kg

Fuel: solid

Burn time: 40 s

Status: Retired 1966.

Gross mass: {{convert|10,700|kg|lb|abbr=on}}.

Unfuelled mass: {{convert|1,200|kg|lb|abbr=on}}.

Height: {{convert|9.40|m|ft|abbr=on}}.

Diameter: {{convert|1.02|m|ft|abbr=on}}.

Thrust: 440.00 kN (98,910 lbf).

Burn time: 44 s.

Number: 20.

Algol II

Image:ScoutB annotated.svg

The Algol 2 (Algol II) series was first flown in 1962.

It was used a first stage on Scout A, Scout B, Scout X-3, Scout X-4;

It was proposed as a strap-on motor for the Titan 3BAS2 variant (cancelled). It was also proposed for the Athena RTX program in 1969, losing to Thiokol. B-165488, JAN. 17, 1969. Thrust (sl): 513.300 kN (115,394 lbf; 52,347 kgf).

The 3BAS2 configuration of Titan 3B rocket proposed by Martin in the mid-1960s would have been used for deep space missions with a Centaur upper stage, Algol strap-on for liftoff thrust augmentation. It was never flown.

CSD solid rocket engine. 564.2 kN. Isp=255s.

Gross mass: {{convert|11,600|kg|lb|abbr=on}}.

Unfuelled mass: {{convert|1,650|kg|lb|abbr=on}}.

Height: {{convert|9.09|m|ft|abbr=on}}.

Diameter: {{convert|1.01|m|ft|abbr=on}}.

Thrust: 564.20 kN (126,837 lbf).

Specific impulse: 255 s.

Specific impulse sea level: 232 s.

The Algol II-A was introduced in 1963 using the Aerojet 40 KS motor. It first flew on Scout-X3 in 1963.

The Algol II-B was created after an Algol II-A flight failure, the nozzle was designed and designate the II-B model. It first flew on Scout-X4

The Algol II-C flew on Scout A1 and B1. Scout-A2, -B2, -C and -2 versions planned for Algol II-C were never used.

See also

References

{{Reflist}}

{{Scout rockets}}

{{Suborbital rocket engines}}

Category:Rocket stages

Category:Solid-fuel rockets