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Targets and Decoys

Aries Ballistic Missile Target

(November 21, 2002) The Aries ballistic missile target as seen through the infrared seeker of the developmental Standard Missile-3 (SM-3) Kinetic Warhead moments before intercept at an altitude of approximately 500,000 feet. The target missile was launched from the Pacific Missile Range Facility, Barking Sands, Kauai, Hawaii, while the intercept missile was launched from the Pearl Harbor-based Aegis cruiser USS Lake Erie (CG 70). This was the third consecutive successful intercept by the Aegis Ballistic Missile Defense program and the first intercept during the ascent phase of the target's flight.

2.2 Meter Balloon

The 2.2 Meter balloon deployment was demonstrated in the zero-G facility at NASA Glenn Research Center. The packaging scheme was that used on the IEO. The ejector and launch tube were the same as for the LREP. As with most of our inflatable targets, the optical properties can be adjusted using special coatings. The unit is debris free. The diameter, spin rate, and the coning angle can also be adjusted as well as the radar cross section.

 
 

 2.2 meter balloon with black side out.

 Internal inflation system

 

 2.2 meter balloon canister

Lightweight Replica LREP

Six inflatable LREPs were flown on Talos-Sergeant-Hydac rockets. The missions were called HAVE JEEP 7A, 7B, and 7C. The rocket failed on HJ 7B. Four LREPs were ejected on the remaining flights.

 The LREP in space.

 

Inflatable Exoatmospheric Object (IEO)

The technology for the Inflatable Exoatmospheric Object (IEO) was an extension of a trade study and preliminary design performed on the Exoatmospheric Decoy Program. MlT/Lincoln Laboratory contracted for the development of a balloon decoy which would be a credible exoatmospheric optical-radar replica of a Mark-12 Reentry Vehicle. The IEO Mark 2 version was developed for the RVTO-3A program with the objective of obtaining optical and radar signatures of the IEO during midcourse and early reentry, determining if the IEO and Mark 12 surface temperatures match to within 10K, determining the reentry altitudes that the optical signatures, radar signatures, and ballistic coefficients of the IEO and the Mk-12 clearly diverge, and determining the physical survival altitude of the IEO.

The IEO configuration for the RVTO-3A consisted of an inflatable bladder replicating the Mk 12 external shape, a carbon fabric outer skin for optical and radar matching, an integrated water blanket between the inflatable and the outer skin for surface temperature control, a triaxial magnetometer for determining attitude and dynamics, and a nose positioned S-band telemetry system to transmit IEO temperature, pressure, acceleration and telemetry housekeeping data. A unique Ejection Deployment Mechanism (EDM) was used to store the packaged IEO and then inflate, spin and eject it. The design of the IEO and the EDM were unique because it allowed a debris-free ejection of a complex target. The IEO was flown on an Atlas F booster. The payloads, in addition to the IEO, were a Mk-12 Reentry Vehicle and calibration balloons.

 

Firefly

The Firefly is the most heavily instrumented inflatable target L'Garde has designed, tested and flown. It was built for Lincoln Laboratory's FIREFLY experiment. This was designed to test the ability of a 100 Joule LWIR laser beam for discriminating a decoy from a re-entry vehicle on the basis of decoy dynamics. The target was designed and built with different optical properties in the packaged and deployed states to aid in target acquisition and experiment, respectively. Target design and construction also accommodated observations in the L and X radar bands. The target had to eject with minimal tip-off, spin up to 3 Hz in the packaged state resulting in a 1 Hz spin rate in the deployed state through deliberate mass properties design. It went through a series of coning excursions, opening its precession angle from about 5 degrees to 20 degrees, then 40 and finally back to about 0, while conserving its initial angular momentum vector. The Firefly was instrumented to detect and change its state of motion through an on-board microprocessor and a L'Garde-developed light-weight coning control system; detect its absolute direction in space through a tri-axial magnetometer and a high-resolution sun sensor combination; keep track of all its status and housekeeping functions; and finally, process and telemeter 32 channels of data to both the bus following behind it and to the launch range below.

 

 Firefly canister

 

 The internals of Firefly

Two successful flights above the terminator were conducted using Terrier-Malemute rockets, resulting in excellent data and the proof of principle for the Firepond Laser Radar as a useful discriminator.

   

 Firefly canister

Firefly inflated

 

Multi-Balloon Canister (MBC)

The MBC is intended to provide signature data on lightweight exoatmospheric traffic objects during space flight experiments. These deployed balloons will represent rapidly dispersing target subclusters to allow functional demonstration of tracking algorithms. The MBC concept is that five spherical balloons are compressed into a single canister consisting of a frangible glass tube and end caps. At the designated time, the glass franges and releases the packaged balloons. Upon release, each balloon's passive gas generator inflates the balloon, imparting a random dispersion velocity to all the balloons simultaneously. Each balloon has its own supply of inflatant and is, therefore, independent of the other balloons. Balloons were designed to meet optical and radar property requirements.

 

 One of the inflatable balloons of the MBC.
 

 The MBC canister. Five of the above balloons fit in a single canister.

The MBC includes an ejector that imparts a specified velocity to the canister and begins a timer to initiate its opening. The firing signal is provided by the bus.

The overall system is designed to have no radar observable debris and only minimal optically observable debris.

The MBC design is based on two other L'Garde systems - CSO and SRMP - both of which have flown successfully.

The frangible glass tube was used in the Closely Spaced Objects (CSOs) of the Red Tigress II program. This tube shatters into thousands of very small pieces, releasing its contents. The inflation technique adapts the CSO's use of an inflatant that sublimates to generate a gas to inflate the balloon. Four CSOs flew on two Red Tigress II sounding rocket missions: two on Red Tigress IIA and two on Red Tigress IIB.

The ejector closely models the LREP ejector. The LREP flew successfully on Talos-Sergeant-Hydac rockets, ejecting four LREPs on two separate missions.

The diameter, shape, number, and optical properties of the inflatables can be easily tailored for different missions.

Sources and Resources



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http://www.fas.org/spp/starwars/program/targets.htm
Maintained by Steven Aftergood
Originally created by John Pike
Updated November 22, 2002