From ARG.

Orbital Sciences Corp (Public, NYSE:ORB) announced on February 7th 2011 that it had successfully launched a a U.S. Government payload into orbit on February 5th 2011 from Vandenberg Air Force Base, California. On a February 6th 2011 announcement the NRO (National Reconnaissance Office) announced its successful launch of a payload aboard a Minautor I rocket from Space Launch Complex 8, Vandenberg Air Force Base, California , at 4:26 A.M PST on February 6th 2011.The NRO is the joint Department of Defense-Intelligence community organization that, according to its web site “designs, builds and operates the national reconnaissance satellites” and has been officially operating for the past 50 years.Orbital Science Corporation is a relatively small company founded in 1982 and employing approximately 3,700 peoples and is headquartered in Dulles, Virginia. Orbital generated revenues of $1.2 Billion in 2009 with a net income of $37 million. We are taking interest in a company designing and operating profitably a fleet of lower cost Space Launch Vehicles. The company aims at extracting maximum value from expert integration of existing commercial systems, subsystems and components together with US Government sourced excess Inter Continental Ballistic Missiles into space launch vehicles for various payload market segments. In that sense we will see how some of its most successful launch systems integrate entire motor assemblies from surplus US government Minuteman and Peacekeepers ICBM (Inter Continental Ballistic Missile). We’ll even see how one of its launch systems requires being transported and released to an altitude of 30,000 feet by a modified Lockheed L-1011 TriStar airliner prior to igniting its motors on its course into orbit. We will look at major SLV (Space Launch Vehicles) systems in Orbital fleet, namely Pegasus , Minautor I , Minautor IV, Taurus and Taurus II.

Minautor I, IV And Joint Effort With The US Air Force

The launch of February 5th (or the 6th depending on the source) obviously involving a sensitive payload was conducted aboard by a Minautor I SLV. The Minautor I is a very successful program that has achieved 100% rate of success on 20 launches beginning in the year 2000. It was governed by the OSP-2 Orbital/Suborbital Program 2 in which Orbital is supplier for the Space Launch Vehicle and the US Air Force is in charge of managing the program via Detachment 12 ,Launch Test Squadron of the Space Development and Test Wing (SDTW) as part of the USAF Space and Missile Systems Center at Kirtland Air Force Base, New Mexico.

The Minautor I is a ground launched solid propellant rocket that is very versatile and ideally suited for under 738 lbm (335 kq) type of payload. Although the rocket consists of 4 different stages assemblies each incorporating a rocket motor corresponding to each successive phases of the transition into orbit, Minautor I is better described by Orbital as 2-stack vehicle.The lower stack that incorporates stage 1 and 2 rocket motors assemblies is no-other than the same stage 1 and 2 motors found on the old Minuteman (LGM-30) Inter Continental Ballistic Missiles (respectively the M55A1 solid propellant 1st stage motor and 2nd stage SR19 liquid injection thrust vectored control subsystem). Due to imposed reductions on strategic nuclear-carrying ICBM under various international treaties, thousands of space-capable propulsion assemblies subsystems became surplus. The US government has been able to transfer ready-to-use Minuteman ICBM rockets motor assemblies to the Orbital Science Corporation for their second life as dedicated orbit lift systems for the Minautor I SLV.The upper stack that incorporates stage 3 and 4 assemblies that house respectively the ATK (Alliant Techservices forporation) produced Orion 50XL and Orion 38 motors.

The Minautor IV is a heavier payload SLV than the Minautor I that can deliver payload of up to 3,860 lbm (1,750 kg) in orbit. This model again brings into play US government supplied boosters from former Peacekeepers LGM-118A ICBMs. The base Peacekeeper booster used by Minautor IV comprises 3 of the lower stage propulsion subsystems for the Minautor IV while the stage 4 assembly motor houses the Orion 38 that we have also seen seen on the Minautor I stage 4 an optional Star 48V can be added to add more velocity on specific payload for orbital entry.

The Pegasus and how a reconfigured Lockheed L-1011 airliner can be used to deliver payload into orbit.

In a program that began in the 1990’s, Orbital was able to develop an aircraft-delivered SLV solutions. The Pegasus rocket designed to carry small payload into orbit is transported attached to the under-belly of a specially fitted Lockheed L-1011 Tristar airliner to an altitude of 39,000 ft (11,900 m) from which it is released at an optimal speed of Mach 0.82. Five seconds after release from the aircraft the Pegasus rocket will ignite motors and transitions to orbit in less than 10 minutes under typical conditions. Because it is very small (16.9 m length) it allows Orbital to offer a very low cost of entry and a flexible space launch alternative.Because it is set to be released at Mach 0.82, the 3 stages Pegasus rocket incorporates wings in stage 1. Flying to 178,900 ft the wings-equipped stage 1 motor assembly section will separate and the craft will continue towards orbit with successively employing stage 2 and stage 3 assemblies’ motors. Mootors employed are all Orion family boost motors supplied by ATK (Alliant Techservices). Stage 1 motor is an Orion 50S, stage 2 uses an Orion 50 and stage 3 has an Orion 38.

The L-1011 “Stargazer” Orbital Carrier Aircraft OCA.

OCA designates the Orbital Sciences Corporation program that employs an aircraft as a launch vector for SLV. Again in this scenario Orbital is consistent in its strategy of extensively employing proven commercially available lower cost technology. It has put to very good use N140SC Lockheed Tri-Star L-1011 re-christened “Stargazer”. The airliner turned OCA a 1974 build previously served in its commercial civilian capacity with Air Canada and Air Lanka. FAA currently lists the aircraft as owned by the Orbital Science Corporation of Mojave, California.

The Taurus and Taurus II

The Taurus SLV is a 1,590-kilogram (3,500-pound) ground launched version of the Pegasus but benefits from a much higher payload capability and therefore has 4 stages/motors assemblies. The lower stage ATK Castor 120 boost motor is used as stage 0 assembly while stage 1 assembly uses ATK Orion 50SG/SXLG, stage 2 assembly ATK Orion 50 or Orion 50XL, and finally stage 3 assembly ATK Orion 38.

Taurus II LSV brings additional increase in payload weight over the Taurus I. It can in fact accommodate up 12,700 lbm (5,750 kg). Using a 2 stages motor/assembly configuration, the Taurus II stage 1 employs 2 heavy lift Aerojet A26-62 motors side-by-side in one assembly. These powerful motors are built under Russian license by Aerojet-General Corporation (subsidiary of Gencorp). The stage 2 motor is the ATK Castor 30A (a variant based on the ATK Castor 120 motor that we have seen in use with Taurus stage 1) and finally has option to accommodate an additional 3rd stage STAR 48V motor also built by ATK.

Avionics.

With cost savings in mind Orbital makes extensive re-use of components in its engineering management approach in order to save cost and increase commonality between various SLV. It is more visible with the modular component-based MACH (Modular Avionics Control Hardware) avionics system that has been deployed across the entire fleet of SLV. Not only do we find MACH with each SLV as the main avionics module comprising flight computer, Inertial Navigation System, telemetry system, electrical power, reaction control system, ordnance driver unit but it is also present across the various assembly stages that comprise each SLV. In this role MACH operates the following functions: nozzle Thrust Vectored Control, flight termination system, ordnance driver unit controlling each SLV and also manage stage separation from the main vehicle. True to its strategy Orbital also incorporates commercially available sub components for its MACH systems. For instance on the Taurus craft, we find an avionics suite powered by a 32-bit microprocessor architecture along with familiar open standards technology such as RS-422 / RS-485 serial link data communication.

Regarding avionics.

With cost savings in mind Orbital makes extensive re-use of components in its engineering management approach in order to save cost and increase commonality between various SLV. It is more visible with the modular component-based MACH (Modular Avionics Control Hardware) avionics system that has been deployed across the entire fleet of SLV. Not only do we find MACH with each SLV as the main avionics module comprising flight computer, Inertial Navigation System, telemetry system, electrical power, reaction control system, ordnance driver unit but it is also present across the various assembly stages that comprise each SLV. In this role MACH operates the following functions: nozzle Thrust Vectored Control, flight termination system, ordnance driver unit

controlling each SLV and also manage stage separation from the main vehicle. True to its strategy Orbital also incorporates commercially available sub components for its MACH systems. For instance on the Taurus craft, we find an avionics suite powered by a 32-bit microprocessor architecture along with familiar open standards technology such as RS-422 / RS-485 serial link data communication.

In all Orbital Sciences Corporation is able to deliver highly flexible lower cost space launch services thanks to a combination of sourcing strategy form government and various commercial partner. While the involvement of organization like Launch Test Squadron of the Space Development and Test Wing (SDTW) dramatically reduces the management risks involved in each mission. However there is inherent complexity in managing the integration of disparate and multi-sourced software, hardware and various sub-components and assemblies. Orbital an ISO 9001:2008 certified presents a very strong operational performance on its LSV program. To date the company boasts 8 successful Taurus missions (100% rate ), 20 for Minautor (100% success rate ), 38 for Pegasus (95% success rate).

Notes:

http://www.orbital.com/NewsInfo/Publications/Taurus_II_Guide.pdf

http://www.atk.com/capabilities_space/documents/ATK_Catalog_May_2008.pdf

http://www.nro.gov/PressReleases/NROL-66%20Release%20%206%20FEB%202011.pdf

http://www.gencorp.com/

http://www.aerojet.com/capabilities/spacelift.php

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