- Covering the Past, Present and Future of
Athena I Fact Sheet
Written and Edited by Cliff Lethbridge
Classification: Space Launch Vehicle
Length: 65 feet
Diameter: 7 feet, 9 inches
What eventually became known as the Athena rocket program (not to be confused with the Atlantic Research Corporation Athena ballistic missile research program of the mid-1960's) began in January, 1993 as Lockheed decided to capitalize on its rocketry potential.
Lockheed believed that the timing was right to apply its cumulative solid-propellant Polaris, Poseidon and Trident missile technology to the ever-emerging field of launching relatively lightweight payloads into space.
The initial vehicle program that emerged was named Lockheed Launch Vehicle (LLV). After Lockheed merged with Martin Marietta to form Lockheed Martin, the program was renamed Lockheed Martin Launch Vehicle (LMLV).
The core launch vehicle was named LMLV-1, with a larger version named
LMLV-2. LMLV-1 was later renamed Athena I, while LMLV-2 was renamed Athena II.
A third version, called the Athena III, has also been introduced but to date
has not been launched from
The Athena I is a two-stage, solid-fueled rocket capable of carrying a maximum 1,750-pound payload into low-Earth orbit.
A Thiokol Castor 120 solid rocket motor serves as the Athena I first stage. The first stage is 28 feet, 9 inches long by 7 feet, 9 inches wide and burns Class 1.3 Hydroxyl-terminated polybutadiene (HTPB) solid propellant. The first stage can produce a thrust of 435,000 pounds at launch.
The first stage motor is housed in a composite case and is steered by blowdown cold gas-powered hydraulic thrust vector control (TVC) actuators. In a typical flight profile, the first stage burns out about 90 seconds after launch, after which the vehicle begins an unpowered coast period. The first stage remains attached to the vehicle during this coast to provide aerodynamic stability.
A Pratt and Whitney Orbus 21D solid rocket motor serves as the Athena I second stage. The second stage is 10 feet, 4 inches long by 7 feet, 8 inches wide and, like the first stage, burns Class 1.3 HTPB solid propellant. The second stage can produce a thrust of 43,723 pounds.
The second stage motor is housed in a composite case and employs a carbon phenolic nozzle steered by electromechanical TVC actuators. In a typical flight profile, the second stage is fired about 200 seconds after launch and about two seconds following first stage separation. The second stage burns out about 145 seconds after it is fired.
The second stage separates less than one second after it burns out, at which time an Orbit Adjust Module (OAM) attached to the payload is fired. The OAM houses a Primex Technologies attitude control system, as well as an avionics subsystem. The OAM includes guidance and navigation controls, batteries, telemetry transmitters, command and destruct receivers and antennas.
The OAM can be ignited, shut down and restarted to perform orbital injection attitude corrections, roll control, velocity trim and orbit circularizing maneuvers. The OAM can carry a maximum 960 pounds of hydrazine liquid fuel. After the OAM completes its role, it separates from the payload and executes a collision avoidance maneuver away from the payload until its fuel is depleted.
The Athena I employs a standard payload fairing which is 14 feet, 1 inch long by 6 feet, 6 inches wide. Considered a "stack and shoot" type of launch vehicle, the Athena I is designed to be launched in as little as 30 days after the first stage arrives at the launch site.
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