Space Launch Report . . . Taurus Data Sheet
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Air Force Taurus T-05 
Taurus

Taurus is a four stage solid fuel expendable that combines a Peacekeeper (MX) ICBM-type first stage with three Orbital Sciences Pegasus upper stages.  A Pegasus avionics assembly, mounted atop the upper stage,  provides vehicle guidance and control. 

Three variants are available.  For DoD missions, ARPA/Air Force Taurus (Taurus 1000-series)  is powered by a surplus Thiokol Peacekeeper first stage.   For commercial launches, Taurus-120 (Taurus 2000-series) uses a Thiokol Castor-120 in place of the Peacekeeper stage.  Another commercial variant, Taurus XL (Taurus 3000-series), is also available.  Taurus XL uses a Castor-120 first stage and three Pegasus XL upper stages.  ARPA Taurus uses a 1.6 meter diameter payload fairing.  The commercial variants can use 1.6 or 2.34 meter fairings. 

Thiokol's Castor-120 is a commercial derivative of the Peacekeeper first stage that also powered Lockheed Martin's Athena.  Castor-120 has a less aggressive thrust profile than Peacekeeper, with less maximum thrust and a longer burn time.  Orbital Sciences calls the Taurus first stage "Stage-0" in order to keep the Pegasus stage names, "Stage-1, 2, and 3".  An optional Star 37 fourth stage can also be used for higher energy missions.   

The first Taurus demonstration flight, for ARPA, occurred in 1994.  Taurus did not fly again until 1998, and it has flown infrequently since. The sixth launch failed to reach orbit in 2001 when a second stage thrust vector control actuator stuck for a few seconds at the start of the stage burn. The Taurus stages all fired, but the momentary loss of directional control caused a velocity shortfall.   Taurus performed a successful flight in 2004, but no more launches are planned until the end of 2008 at the earliest.

Taurus lifts off from a pedestal platform equipped with a fallback umbilical and minimal support equipment.  All previous launches have taken place from Vandenberg AFB SLC 567E.  Other potential Taurus launch sites include Vandenberg AFB SLC 8 (California Launch Facility); Wallops Island, Virginia; Kodiak Island, Alaska, and Cape Canaveral SLC 46. 

Vehicle Configurations

  LEO Payload
(metric tons)
400 km x 28 deg
LEO Payload
(metric tons)
400 km x 98 deg
Configuration LIftoff
Height
(meters)
Liftoff
Mass
(metric tons)
Taurus 1110 1.150 t 0.820 t MX Stg1 + Orion 50S + Orion50 + Orion38 26 m 73.00 t
Taurus 2110 1.259 t 0.889 t Castor 120 + Orion 50SG + Orion50 + Orion38 + 1.6mPLF 27 m 73.03 t
Taurus 2210 1.047 t 0.695 t Castor 120 + Orion 50SG + Orion50 + Orion38 + 2.34mPLF 27 m 73.03 t
Taurus 3110 1.458 t 1.054 t Castor 120 + Orion 50SXLG + Orion50XL + Orion38 + 1.6mPLF 32 m 77.00 t
Taurus 3210 1.276 t 0.882 t Castor 120 + Orion 50SXLG + Orion50XL + Orion38 + 2.34mPLF 32 m 77.00 t

Vehicle Components

  Stg 0
(MX Stg 1)
Stg 0
Castor 120
Stg 1
(Orion 50S(G)
Stg 2
(Orion 50)
Stg 2
(Orion50XL)
Stg 3
(Orion38)
Payload
Fairing
Diameter (m) 2.38 m 2.38 m 1.27 m 1.28 m 1.28 m 0.97 m 1.6 m/2.34 m
Length (m) 12.8 m 12.8 m 8.9 m 2.64 m 3.58 m 2.08 m ~4 m/~6 m
Propellant Mass (tonnes)   48.96 t 12.147 t 3.024 t 3.925 t 0.770 t  
Empty Mass (tonnes)   4.211 t 1.873 t 0.346 t 0.406 t 0.203 t  
Total Mass (tonnes) 53.02 t 53.171 t 14.020 t 3.370 t 4.331 t 0.973 t ~0.3 t/~0.3 t
Engine   Castor 120 Orion 50S(G) Orion 50 Orion50 Orion38  
Engine Mfgr ATK ATK ATK ATK ATK ATK  
Fuel Solid HTPB Solid HTPB Solid HTPB Solid HTPB Solid HTPB Solid HTPB  
Oxidizer      
     
Thrust
(SL tons)
     
     
Thrust
(Vac tons)
224.796 t 164.665 t 48.073 t 11.75 t 15.653 t 3.525 t  
ISP (SL sec)      
     
ISP (Vac sec)   282 s 285 s 290 s 290 s 287 s  
Burn Time (sec) 60.9 s 82.5 t 73 s 75.1 s 73 s 68.5 s  
No. Engines/Motors 1 1 1 1 1 1  
Example Launch Timeline
Air Force Taurus to LEO Orbit from Vandenberg
==========================================================
Event                 Time   Altitude  Range  Velocity
                      (sec)  (nmi)     (nmi)  (ft/sec)
-------------------------------------------------------------
S0 Start               0.0     0.0       0          0
S0 Sep/S1 Start       60.9    20.2      21      7,016
S1 Burnout           140.5    92.1     141     14,940
S1 Sep               145.6    97.7     152     14,870
S2 Start             147.7   100.0     157     14,504
Fairing Sep          152.7   105.5     167     14,706
S2 Burnout           229.0   174.4     371     20,732
S2 Sep               531.9   307.3   1,307     19,595
S3 Start             542.9   309.3   1,341     19,579
S3 Burnout           617.2   314.0   1,574     24,834
Payload Sep          732.0      
==========================================================
Example Launch Timeline
Commercial/Taurus-120 to LEO Orbit from Vandenberg 
==========================================================
Event                 Time   Altitude  Range  Velocity
                      (sec)  (nmi)     (nmi)  (ft/sec)
-------------------------------------------------------------
S0 Start               0.0     0.0       0          0
S0 Sep/S1 Start       81.5    21.0      30      6,824
S1 Burnout/Sep       154.7    61.0     147     14,974
S2 Start             166.8    69.0     175     14,885
Fairing Sep          169.8    71.0     182     15,010
S2 Burnout           247.5   117.0     405     21,726
S2 Sep/S3 Start      635.0   249.0   1,685     20,759
S3 Burnout           704.0   250.0   1,901     25,305
Payload Sep          764.0   250.0   2,116     25,305 
==========================================================
Reference:  Taurus Payload Users Guide, OSC, March 2006
Updated September 24, 2007