The
U.S. Air Force in October selected a package that provides mobile communications
services, data relay from terrestrial sensors and friendly forces tracking as the payload aboard
the fourth satellite in the TacSat series, according to a Defense Department
official.
The all-telecom payload
for the TacSat-4 mission won out over candidates that included a radar-imaging
sensor that has been pushed by the U.S. Army, said Lloyd Feldman, assistant director
of science and technology in the Pentagon's Office of Force Transformation.
TacSat 4, tentatively
scheduled for launch in late 2007, also will feature the prototype standardized
satellite platform that the Air Force will be able to buy in bulk and adapt to a
variety of future missions, Feldman said in an interview here at the Geoint 2005 Symposium.
The TacSat effort is a series of missions intended to
demonstrate that small, low-cost satellites can be deployed quickly to meet a pressing
need of commanders in a theater of operations. It is a key component of a wider
initiative championed by the Office
of Force Transformation known as Operationally Responsive Space.
Equipped with
relatively modest capabilities, TacSat satellites are designed to
operate in concert with other platforms such as aircraft and be tasked from the
field using the Secret Internet Protocol Network, or
Siprnet, a classified version of the Internet available to the U.S. military.
"It's about not
building a Carnegie Hall every time you want to hear some music," Feldman said.
The data relay, or
"exfiltration," payload on TacSat 4, for example, would pick up and retransmit
tactically useful data from sensors on buoys or on the ground, Feldman said.
The
TacSat 1 and 2 satellites will carry imaging sensors that cover a wide area at
coarse resolutions and directly cue aircraft equipped with higher-resolution
sensors for a closer look and identification. Those satellites also will carry
radio-signal fingerprinting devices that will enable the military to
immediately identify an object, be it a boat, aircraft or ground vehicle, whenever
its signals are picked up in the future.
TacSat 2 also will
carry a payload that will pick up and relay signals from identification beacon
signals aboard ships, Feldman said.
TacSat 3's main payload
is a hyperspectral sensor and the satellite platform will have a standardized
avionics package whose development is being managed by the Air Force Research
Laboratory.
The Naval Research
Laboratory in Washington and the Johns Hopkins University's Applied Physics
Laboratory in Laurel, Md., are leading the effort to develop the standardized TacSat
platform that will be demonstrated on the fourth mission, Feldman said. Once proven,
the Air Force Space and Missile Systems Center, which procures U.S. military space
hardware, could solicit bids for multiple platforms.
Feldman said the cost
of these platforms, which feature standardized payload interfaces, could fall
between $8 million and $5 million, depending on the quantity ordered. A study
by the Massachusetts Institute of Technology's Lincoln Laboratory found that
such a platform, weighing between 100 and 200 kilograms, could fulfill 80
percent of the TacSat mission requirements, Feldman said.
Of the four TacSat
missions in the pipeline, only TacSat 1, utilizing a commercial Orbcomm
satellite communications platform, has a launch arranged. It is slated to fly
in early 2006 aboard Space Exploration Technologies Corp.'s Falcon 1 rocket,
either from Vandenberg Air Force Base, Calif., or the Kwajalein Atoll in the
Pacific.
TacSat 2, which
utilizes hardware leftover from the Air Force's canceled TechSat 21 experiment,
has no assigned launcher even though it is slated to launch in late 2006. The same
goes for TacSat 3 and TacSat 4, tentatively scheduled to launch in early and
late 2007, respectively, Feldman said.
Comments:
wferster@space.com
