Continuing our look at U.S. launch vehicles, we turn our spotlight onto Orbital Sciences Corporation. Although the Virginia company is traditionally a supplier of small launch vehicles, it recently made the leap to medium-lift rockets.
Orbital currently operates four launch vehicles:
- Pegasus, an air-launched solid-fuel vehicle for small satellites;
- Taurus, a land-based variant of the Pegasus booster with a decommissioned Peacekeeper ballistic missile used as the first stage;
- Minotaur, a family of small solid-fuel launchers that uses a mixture of decommissioned Peacekeeper and Minuteman II ballistic missile stages and Pegasus and Taurus technology; and,
- Antares, a new medium-class, liquid-fuel booster developed under NASA’s Commercial Orbital Transportation Services (COTS) program that will launch Cygnus freighters to the International Space Station.
The company also is developing a new air-launched rocket nicknamed Pegasus II for Paul Allen’s Stratolaunch Systems company. This new medium launch vehicle is set to make its debut flight in 2016.
Let’s now take a closer look at Orbital’s programs. The launch history tables below are adapted from Wikipedia.
Named for the mythical winged horse, Pegasus is an air-launched booster carried aloft by a L-1011 jetliner named Stargazer after a ship that fictional Star Fleet Capt. Jean-Luc Picard once served on. The rocket has three solid-fuel stages with an optional liquid fourth stage that is capable of delivering payloads weighing 443 kg (980 lbs) into low Earth orbit.
Pegasus has flown 42 missions between 1990 and 2013, with 37 successes, two partial successes, and three failures. The last Pegasus failure was 17 years ago in 1996.
|1||April 5, 1990||Pegsat, NavySat||Success|
|2||July 17, 1991||Microsats (7 satellites)||Partial success (orbit slightly low)|
|3||February 9, 1993||SCD-1||Success|
|4||April 25, 1993||ALEXIS – Array of Low Energy X-ray Imaging Sensors||Success|
|5||May 19, 1994||STEP-2 (Space Test Experiments Platform/Mission 2/SIDEX)||Partial success (orbit slightly low)|
|6||June 27, 1994||STEP-1 (Space Test Experiments Platform/Mission 1)||Failure (destroyed approx. 3 minutes after launch)|
|7||August 3, 1994||APEX||Success|
|8||April 3, 1995||Orbcomm (2 satellites), OrbView-1||Success|
|9||June 22, 1995||STEP-3 (Space Test Experiments Platform/Mission 3)||Failure (destroyed between first- and second-stage flight)|
|10||March 9, 1996||REX II||Success|
|11||May 17, 1996||MSTI-3||Success|
|12||July 2, 1996||TOMS – Total Ozone Mapping Spectrometer||Success|
|13||August 21, 1996||FAST (Fast Auroral Snapshot Explorer)||Success|
|14||November 4, 1996||HETE, SAC-B||Failure (Satellites not ejected from third stage)|
|15||April 21, 1997||MiniSat, Celestis space burial||Success|
|16||August 1, 1997||OrbView-2||Success|
|17||August 29, 1997||FORTE||Success|
|18||October 22, 1997||STEP-4 (Space Test Experiments Platform/Mission 4)||Success (However, satellite never activated, solar panels failed to deploy)|
|19||December 23, 1997||Orbcomm (8 satellites)||Success|
|20||February 26, 1998||SNOE, BATSAT||Success|
|21||April 2, 1998||TRACE||Success|
|22||August 2, 1998||Orbcomm (8 satellites)||Success|
|23||September 23, 1998||Orbcomm (8 satellites)||Success|
|24||October 22, 1998||SCD-2||Success|
|25||December 6, 1998||SWAS||Success|
|26||March 5, 1999||WIRE – Wide Field Infrared Explorer||Success|
|27||May 18, 1999||Terriers, MUBLCOM||Success|
|28||December 4, 1999||Orbcomm (7 satellites)||Success|
|29||June 7, 2000||TSX-5 (Tri-Services Experiments Platform/Mission 5)||Success|
|30||October 9, 2000||HETE 2||Success|
|31||February 5, 2002||RHESSI||Success|
|32||January 25, 2003||SORCE||Success|
|33||April 28, 2003||GALEX – Galaxy Evolution Explorer||Success|
|34||June 26, 2003||OrbView-3||Success|
|35||August 13, 2003||SCISAT-1||Success|
|36||May 15, 2005||DART||Success|
|37||March 28, 2006||ST-5 – Space Technology 5 (3 satellites)||Success|
|38||April 25, 2007||AIM – Aeronomy of Ice in the Mesosphere||Success|
|39||April 16, 2008||C/NOFS||Success|
|40||October 19, 2008||IBEX – Interstellar Boundary Explorer||Success|
|41||June 13, 2012||NuSTAR – Nuclear Spectroscopic Telescope Array||Success|
|42||June 28, 2013||IRIS – Interface Region Imaging Spectrograph SMEX||Success|
Despite its reliability, demand for Pegasus launches has declined in recent years as the price of launches has risen. Pegasus launches were priced at $11 million in 1990. NASA paid Orbital about $36 million to launch its NuSTAR satellite in 2012, and about $40 million for the IRIS spacecraft launched earlier this year.
In June 2012, Orbital officials said they might end production of Pegasus boosters after NASA canceled its Gravity and Extreme Magnetism Small Explorer (GEMS) X-ray telescope due to cost overruns. However, Orbital has continued the program.
The Taurus rocket is a ground-based, four-stage variant of Orbital’s Pegasus air-launched vehicle. The ATK-supplied Castor 120 first stage is based on the decommissioned Peacekeeper missile. The other stages are adapted from the Pegasus launch vehicle. The all-solid fuel vehicle can launch 1,458-kg (3,214-lb) satellites into low-Earth orbit.
Taurus has been launched nine times over the past 19 years, with six successes and three failures. The rocket suffered back-to-back failures in 2009 and 2011, sending NASA’s Orbiting Carbon Observatory and Glory environmental satellites to the bottom of the Pacific near Antarctica. The cause of both failures was the inability of the payload shrouds to separate from the launch vehicle. The failures cost NASA $700 million, not including the cost of the rockets.
|1||March 13, 1994||STEP 0 (P90-5, USA 101) / DARPASAT (USA 102)||Vandenberg||LEO||Success|
|2||February 10, 1998||GFO and ORBCOMM (Satellites 11,12)||Vandenberg||LEO||Success|
|3||October 3, 1998||Space Technology Experiment (STEX) for National Reconnaissance Office (NRO)||Vandenberg||LEO||Success|
|4||December 20, 1999||KOMPSAT and ACRIMSAT||Vandenberg||LEO||Success|
|5||March 12, 2000||Multispectral Thermal Imager (MTI)||Vandenberg||LEO||Success|
|6||September 21, 2001||Orbview-4/QuikTOMS||Vandenberg||LEO||Failure|
|7||May 20, 2004||ROCSAT-2||Vandenberg||LEO||Success|
|8||February 24, 2009||Orbiting Carbon Observatory||Vandenberg||LEO||Failure|
|9||March 4, 2011||Glory, KySat-1, Hermes, and Explorer-1 [PRIME]||Vandenberg||LEO||Failure|
Although the launch vehicle’s nine flights have all been from Vandenberg Air Force Base in California, Taurus is approved for launch for launch from Cape Canaveral Air Station (CCAS) in Florida, Wallops Flight Facility (WFF) in Virginia, and Kodiak Launch Complex, Alaska.
The Minotaur family of rockets is Orbital’s most reliable launch vehicle, with a perfect operational record of 23 successes and no failures.
The launch vehicles use solid-fuel stages from decommissioned Minuteman II and Peacekeeper intercontinental ballistic missiles combined with stages and systems from Orbital’s Pegasus and Taurus rockets. The Minotaur comes in four main variants:
Minotaur I: This launch vehicle uses Minuteman II motors for the first and second stages, and Pegasus XL technology for the third and fourth stages. The Minotaur II can launch payloads weighing 580 kg (1,278 lbs) into low Earth orbit.
Minotaur II: The suborbital rocket uses first and second stages from Minuteman missiles with various third stages: M57A1 (Minuteman II), SR-73-AJ (Minotaur II+), and Orion 50XL (Minuteman II Heavy). The Minotaur II Lite variant has no third stage.
The Minotaur II baseline configuration can launch 400 kg (880 lbs) payload to 4,000 kilometers (2,500 miles) downrange. The Minotaur II Heavy can launch a 1,400-kg (3,100-lb) payload to a distance of 8,000 kilometers (5,000 miles) downrange.
Minotaur IV: This variant uses three Peacekeeper solid rocket stages, a commercial Orion 38 fourth-stage motor, and Pegasus and Taurus subsystems. It can launch 1,730 kg (3,814 lbs) to low Earth orbit.
Minotaur V: Adaptation of Minotaur IV with a fifth stage motor for small GTO, lunar, and interplanetary missions.
Minotaur V is scheduled to make its inaugural flight next month, launching NASA’s Lunar Atmosphere and Dust Environment Explorer (LADEE) mission from Wallops Island, Virginia.
|1||January 27, 2000||Minotaur I||JAWSat (P98-1) (FalconSat1)/ASUSat1/OCSE/OPAL)||Vandenberg||LEO||Success|
|2||May 28, 2000||Minotaur II||OSP-TLV Missile Defense Technology Demonstrator||Vandenberg||Suborbital||Success|
|3||July 19, 2000||Minotaur I||MightySat II.1 (Sindri, P99-1) / MEMS 2A / MEMS 2B||Vandenberg||LEO||Success|
|4||December 4, 2001||Minotaur II||TLV-1 IFT-7 GMDS target mission||Vandenberg||Suborbital||Success|
|5||March 16, 2002||Minotaur II||TLV-2 IFT-8 GMDS target mission||Vandenberg||Suborbital||Success|
|6||October 15, 2002||Minotaur II||TLV-3 GMDS target mission||Vandenberg||Suborbital||Success|
|7||December 11, 2002||Minotaur II||TLV-4 GMDS target mission||Vandenberg||Suborbital||Success|
|8||April 11, 2005||Minotaur I||XSS-11||Vandenberg||LEO||Success|
|9||September 23, 2005||Minotaur I||Streak (STP-R1)||Vandenberg||LEO||Success|
|10||April 15, 2006||Minotaur I||COSMIC (FORMOSAT-3)||Vandenberg||LEO||Success|
|11||December 16, 2006||Minotaur I||TacSat-2 / GeneSat-1||Mid-Atlantic Regional Spaceport||LEO||Success|
|12||March 21, 2007||Minotaur II||TLV-5 FTX-02 SBR target mission||Vandenberg||Suborbital||Success|
|13||April 24, 2007||Minotaur I||NFIRE||Mid-Atlantic Regional Spaceport||LEO||Success|
|14||August 23, 2007||Minotaur II+||TLV-7 Mission 2a sensor target for NFIRE satellite||Vandenberg||Suborbital||Success|
|15||September 24, 2008||Minotaur II+||TLV-8 Mission 2b sensor target for NFIRE satellite||Vandenberg||Suborbital||Success|
|16||May 19, 2009||Minotaur I||TacSat-3 / PharmaSat / AeroCube 3 / HawkSat I / CP-6||Mid-Atlantic Regional Spaceport||LEO||Success|
|17||April 22, 2010||Minotaur IV Lite||HTV-2a hypersonic research spacecraft||Vandenberg||Suborbital||Success|
|18||September 26, 2010||Minotaur IV||SBSS||Vandenberg||SSO||Success|
|19||November 19, 2010||Minotaur IV HAPS||FASTRAC-A / FASTRAC-B / FalconSat-5 / FASTSAT / O/OREOS / RAX||Kodiak||LEO||Success|
|20||February 6, 2011||Minotaur I||NROL-66||Vandenberg||LEO||Success|
|21||June 30th, 2011||Minotaur I||ORS-1||Mid-Atlantic Regional Spaceport||LEO||Success|
|22||August 11th, 2011||Minotaur IV||Falcon Hypersonic Technology Vehicle 2 (HVT-2b)||Vandenberg||Suborbital||Success|
|23||September 27th, 2011||Minotaur IV||TacSat-4||Kodiak||HEO||Success|
|24||September 2013||Minotaur V||LADEE||Mid-Atlantic Regional Spaceport||Lunar orbit||N/A|
Antares is Orbital’s newest rocket, a medium-lift launch vehicle developed under NASA’s Commercial Orbital Transportation Services (COTS) program to send Cygnus cargo freighters to the International Space Station. It is capable of sending payloads weighing up to 6,120 kg (13,492 lbs) to low Earth orbit.
The Antares is a multinational rocket. Yuzhnoye SDO of Ukraine builds the first stage, which is similar to the company’s Zenit launch vehicle. The stage is powered by two Aerojet AJ26 engines, which are reconditioned Soviet-era NK-33 engines. ATK supplies the rocket’s Castor 30 third stage. Orbital has added systems used in its Pegasus, Taurus and Minotaur rockets.
Antares made a successful inaugural flight on April 21, 2013, carrying a mass simulator for the Cygnus freighter. In September, it will launch Cygnus on a demonstration mission to the International Space Station. If that flight is success, Orbital will launch a series of eight Commercial Resupply Services (CRS) flights to the orbiting facilities, with the first flight scheduled for December.
In addition to Cygnus missions, Orbital is promoting Antares for the type of medium-class missions that are typically launched by United Launch Alliance’s Delta II rocket, which is being retired.
|1||April 21, 2013||Antares A-ONE||Cygnus Mass Simulator|
|Mid-Atlantic Regional spaceport||LEO||Success||Antares test flight|
|2||September 14-19, 2013||COTS Demo||Cygnus 1||Mid-Atlantic Regional spaceport||LEO||N/A||First Cygnus mission|
|3||December 2013||CRS Orb-1||Cygnus 2||Mid-Atlantic Regional spaceport||LEO||N/A||First Cygnus Cargo Resupply Mission (CRS), first Antares launch to use the Castor 30B upper stage|
|4||2014||CRS Orb-2||Cygnus 3||Mid-Atlantic Regional spaceport||LEO||N/A|
|5||2014||CRS Orb-3||Cygnus 4||Mid-Atlantic Regional spaceport||LEO||N/A||First Antares launch to use Castor 30XL upper stage|
|6||2014/2015||CRS Orb-4||Cygnus 5||Mid-Atlantic Regional spaceport||LEO||N/A||First Enhanced Cygnus mission|
Orbital is also developing the multi-stage, air-launch vehicle (ALV) for Microsoft billionaire Paul Allen’s latest space project, Stratolaunch Systems. The launch vehicle, nicknamed Pegasus II, will be taken aloft by a giant carrier aircraft with a wingspan of 385 feet.
Last week, Orbital announced that it had awarded a contract to develop the first two stages of the booster to ATK, with which it has worked since the Pegasus program.
“Our design solution for the ALV will take full advantage of ATK’s experience with large diameter solid rocket motors, like those built for the Space Shuttle and for the Titan IVB launch vehicle. The stages for ALV will also use high-strength, low-weight graphite composite cases, advanced propellants, and heritage materials from ATK’s extensive line of commercial solid rocket motors,” said Scott Lehr, vice president and general manager of ATK’s Defense and Commercial Division.
The rocket will have a restartable, cryogenic third stage and an optional fourth stage. The launch vehicle is being designed to place payloads weighing 6,123.5 kg (13,500 lbs) into low Earth orbit. The payload is nearly identical to that of the Antares rocket.
The carrier aircraft is set to make its first test flight in 2015, with the inaugural launch of the booster scheduled for the following year.