TacSat-2 illustration.jpg
Artist's rendering of TacSat-2
Mission typeTechnology
COSPAR ID2006-058A
SATCAT no.29653Edit this on Wikidata
Spacecraft properties
ManufacturerMicroSat Systems
Launch mass370 kilograms (820 lb)
Start of mission
Launch dateDecember 16, 2006 (2006-12-16)
RocketMinotaur I
Launch siteMARS LP-0B
End of mission
Decay dateFebruary 5, 2011
Orbital parameters
Reference systemGeocentric
RegimeLow Earth
Perigee altitude413 kilometers (257 mi)
Apogee altitude424 kilometers (263 mi)
Inclination40& degrees
Period92.9 minutes
Epoch16 December 2006, 07:00:00 UTC[1]

TacSat-2 (also known as JWS-D1 or RoadRunner)[2] was an experimental satellite built by the USAF's Air Force Research Laboratory with an operational life expected to be not more than one year as part of the 'Advanced Concept Technology Demonstration' program.


The TacSat series of experimental spacecraft are designed to allow military commanders on a battlefield to request and obtain imagery and other data from a satellite as it passes overhead. Collected data will be delivered to field commanders in minutes rather than hours or days. The sensor on TacSat-2 could collect color images sharp enough to distinguish ground objects as small as 1 meter in diameter.[3]


TacSat-2 launch.jpg

TacSat-2 was launched on 16 December 2006 from the Mid-Atlantic Regional Spaceport using an Orbital Sciences Minotaur launch vehicle. The Mid-Atlantic Regional Spaceport is a commercial space launch facility located on the Delmarva Peninsula 5 miles (8.0 km) west of Chincoteague, Virginia.


Satellites in the TacSat series were planned to use commercial or available launchers, and largely off-the-shelf components, in order to reduce costs.


The space platform was built by MicroSat Systems of Littleton, Colorado. The core avionics of the spacecraft including command and data handling, electrical power switching and distribution, and subsystem & payload interfaces was handled by an Integrated Avionics Unit (IAU) developed by Broad Reach Engineering. The spacecraft flight software consisted of the low level drivers, and bus manager functionality provided by Broad Reach Engineering, ADCS Software by ASI, and a number of higher level applications by 3rd parties, most notably the Autonomous Tasking Experiment (ATE) by Interface & Control Systems.

Camera / Telescope

TacSat-2 during integration

The developers originally asked for bids from contractors for a camera. These were priced at around US$10 million. The team then bought a high-end observatory telescope costing around $20,000 and added a camera sensor ($2 million), delivering a sensor capable of 1m ground resolution.[4]

The telescope had 50 cm (0.5 m) aperture and was from RC Optical Systems.[5]

Signals Intelligence

A signals intelligence payload, called the Target Indicator Experiment, detected radio wave emitters and could be used in concert with receivers on other platforms such as the US Navy's P-3C maritime patrol aircraft.

Other systems included:

  • RoadRunner Onboard Processing Experiment (ROPE)
  • Common Data Link (CDL)
  • Autonomous Operations
  • Hall Effect Thruster (HET)
  • Propulsion Instrument Electronics (PIE) sensor suite
  • Inertial Stellar Compass (ISC)
  • Low Power Transceiver (LPT)
  • Integrated GPS Occultation Receiver (IGOR)[6]
  • Atmospheric Density Mass Spectrometer (ADMS)
  • Experimental Solar Array
  • Miniaturized Vibration Isolation System (MVIS)


The near circular orbit had a height of 410 km at an inclination of 40 degrees to the equator. TacSat-2 decayed on February 5, 2011.


Apart from the Air Force Research Laboratory (AFRL), other organisations participating included:

See also


  1. ^ "NASA - NSSDCA - Spacecraft - Trajectory Details". nssdc.gsfc.nasa.gov. Retrieved 2018-05-02.
  2. ^ http://pdf.aiaa.org/preview/CDReadyMSPACE05_1181/PV2005_6830.pdf Archived 2007-09-30 at the Wayback Machine Accessed 28 June 2007
  3. ^ Singer, Jeremy (2006-12-04). "USAF To Experiment With Satellite To Improve Ground Communications". Defense News. Archived from the original on 2012-07-24.
  4. ^ Singer, Jeremy (2006-12-07). "TacSat-2 Ushers in New Era in Satellite Operations". Space News. Retrieved 2008-08-07.[permanent dead link]
  5. ^ Astronautix - Tacsat2 Archived 2011-10-15 at the Wayback Machine
  6. ^ "Integrated GPS Occultation Receiver". Broad Reach Engineering.
  • USAF (2006-09-01), TacSat-2 Micro Satellite (PDF), Air Force Research Laboratory, archived from the original (PDF) on 2007-07-12, retrieved 2006-12-18
  • "TacSat-2 Mission Information". NASA.