|Country of origin||USA|
|Application||Upper stage/Spacecraft propulsion|
|Thrust (vac.)||33.600 kN (7,554 lbf)|
|Isp (vac.)||(161,512 N•s/kg)|
|Length||2.27 m (7.44 ft)|
|Diameter||0.66 m (2.16 ft)|
|Dry weight||113 kg (249 lb)|
|Thor (rocket family), Delta (rocket family), upper stage|
The Star 37 is a type of solid rocket motor used by many space propulsion and launch vehicle stages. It is used almost exclusively as an upper stage. It was developed primarily by Thiokol Propulsion, and now manufactured by ATK (now Orbital ATK) who purchased Thiokol corporation. The Star 37 was first used as the engine for the Thor-Burner upper stage. The Burner I used the Thiokol FW-4 (TE 364-1) engine and the Burner 2 used the Thiokol (TE-M-364-2).
The "-37" designation refers to the approximate diameter of the fuel casing in inches; Thiokol had also manufactured other motors such as the Star-40 and Star 48. Internally, Thiokol's designation was TE-M-364 for early versions, TE-M-714 for later ones, and TE-M-783 for a special HTPB model used for FLTSATCOM launches.
Subtypes are given one or more letter suffixes after the diameter number, or a trailing number (i.e., "-2") after the internal designation. Not surprisingly, the "T" prefix stands for Thiokol, and the following letter refers to the company division that developed the rocket motor. In this case, "M" refers to the Magna, UT Division. "E" refers to the Elkton, MD division.
The Star 37FM rocket motor was developed and qualified for use as an apogee kick motor on FLTSATCOM. The motor is a replacement for the Star 37E Delta, which has been discontinued. The Nozzle assembly uses a 3D carbon-carbon throat and a carbon-phenolic exit cone. Maximum propellant weight is 2350 pounds, while the motor has been qualified for propellant off-loading to 2257 pounds.
The Star 37XFP rocket motor has been qualified as the orbit insertion motor for Rockwell International's (now Boeing) Global Positioning Satellite (GPS), and as the apogee motor for the RCA SATCOM Ku-Band satellite. The Star 37XFP motor can be used as a replacement for the Star 37F motor, which has been discontinued.
Thiokol Star-37 family
|Name (Thiokol #)||Mass (kg)||Mass empty (kg)||Mass prop (kg)||Prop mass fract||Prop||Casing||Thrust vac (kN)||ISP (sec)||Tot. imp. (kNs)||Burn (s)||Diam (m)||Length (m)||Remark|
|Star-37FM (TE-M-783)||1147.4||81.5||1065.9||0.929||HTPB||Titanium||47.26||289.8||3051.35||63||0.93||1.69||Developed and qualified for use as an apogee kick motor on FLTSATCOM|
|Star-37XFP (TE-M-714-17/18)||955.3||71.7||883.6||0.925||HTPB||Titanium||38.03||290.0||2537.49||67||0.93||1.50||Qualified as the orbit insertion motor for Boeing's Global Positioning Satellite (GPS), and as the apogee motor for the RCA SATCOM Ku-Band satellite.|
Burner upper stages
The Burner and Burner 2 rocket stages have been used as upper stages of launch vehicles such as the Thor and Delta since 1965. Burner II was a launch vehicle upper stage developed by Boeing for the Air Force Space Systems Division. It was the first solid-fuel upper stage with full control and guidance capability developed for general space applications.
In March 1964, the DMSP program office approved plans to develop a more powerful Thor Burner 2 launch vehicle. Burner 2 used a Thiokol Star 37B motor (TE-M-364-2). Star 37, from which Star 37B was derived, had originally been developed to serve as the Surveyor lunar lander retro-rocket. Star 37B weighed 718 kg loaded and produced about 4.59 tonnes of thrust for 42 seconds. The Burner 2 stage was fitted with 3-axis control by Boeing, allowing it to coast without spin stabilization after separating from Thor.
Burner II was a launch vehicle upper stage developed by Boeing for the Air Force Space Systems Division. It was the first solid-fuel upper stage with full control and guidance capability developed for general space applications. Burner II was designed for use with the Thor booster, but was readily adapted for use on the complete range of standard launch vehicles. Its general assignment was to place small- and medium size payloads into orbit. The Burner II motor, guidance system and reaction control system were integrated to provide attitude stability and precise control of flight rate and burnout velocity for orbital injection and earth-escape missions. Boeing had delivered 8 flight vehicles under its original contract. Under terms of a follow-on contract, it built 6 additional flight models.
Solid propellant rocket stage. Loaded/empty mass 774/116 kg. Thrust 43.55 kN. Vacuum specific impulse 285 seconds. Thiokol solid rocket engine. 43.5 kN. Total impulse 161,512 kgf-sec. Motor propellant mass fraction 0.899. Isp=260s. First flight 1963. Thrust (sl): 33.600 kN (7,554 lbf). Thrust (sl): 3,428 kgf.
Gross mass: 621 kg (1,369 lb). Unfuelled mass: 63 kg (138 lb). Height: 0.84 m (2.75 ft). Diameter: 0.66 m (2.16 ft). Thrust: 43.50 kN (9,779 lbf). Specific impulse: 260 s. Specific impulse sea level: 220 s. Burn time: 42 s. Number: 180
- ATK Space Propulsion Products Catalog (PDF). ATK. 2008. pp. 80–85. Retrieved 2011-06-14.
- http://www.globalsecurity.org/space/systems/thor.htm Global Security
- http://www.spacelaunchreport.com/thorh6.html Thor H6, Spacelaunch Report
- "Star 37". Encyclopedia Astronautica.