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Towed Decoys Could Improve Navy Aircraft Survivability
In a recent report (GAO/NSIAD-97-94), the General Accounting Office (GAO) has reviewed Department of Defense (DoD) plans to acquire the ALE-50 and radio frequency countermeasures (RFCM) towed decoy systems. The RFCM system includes a more advanced decoy and is part of the integrated defensive electronics countermeasures system being developed for certain Navy and Air Force aircraft.
The report notes that existing onboard electronic warfare systems have limitations against certain threats and that these threats are expected to be improved. Modifications of existing systems to improve their effectiveness have been less than completely successful. To counter these limitations, the services are acquiring both the ALE-50 and RFCM towed decoy systems to improve survivability against radar-controlled threats.
The ALE-50's towed decoy component generates and emits signals to present a more attractive target than the aircraft to incoming radar-guided weapons. The RFCM employs a techniques generator aboard the aircraft to produce jamming signals that are transferred to the RFCM decoy via fiber-optic cable for transmission to the incoming weapon. Both system decoys are single use and, once deployed, are cut loose prior to landing. Each system provides multiple decoys for each aircraft.
The GAO reports that classified tests have shown that the ALE-50 decoy has improved overall effectiveness against radar-controlled threats including some in which self-protection jammers have been ineffective. The RFCM system is expected to improve survivability further because of its more sophisticated jamming techniques.
The Air Force is modifying its aircraft to use the ALE-50 system. Approximately 437 F-16s and 95 B-1s will be equipped for ALE-50 use and 17,306 ALE-50 decoys will be purchased for operational use. The Air Force also is considering use of the RFCM on its F-15s and several other aircraft. The Navy plans to purchase 466 ALE-50 decoys for F/A-18E/F testing and contingencies after the aircraft's deployment until the RFCM decoy is available. The total ALE-50 program cost is estimated at $1.2 B.
As a result of limited flight testing, the Navy does not intend to fit its aircraft for the ALE-50 system. The Navy feels that tests deploying the decoy from wing and centerline stations revealed that the tow line came too close to the horizontal tail or the trailing flap edge when deployed from a wing station and that it could be burned off by engine exhaust or abraded when deployed from a centerline station. The Navy has also expressed further concerns about the need to trade a weapon or fuel tank on a wing or centerline station for a towed decoy. In light of the demonstrated ability of towed decoys to increase aircraft survivability, the ongoing Navy tests of the ALE-50 and its plans to deploy towed decoys from a centerline station on the F/A 18E/F, the GAO recommends that the Navy make a detailed engineering analysis of the modifications needed to adapt the towed decoy to the F/A-18C/D.
Air Force Seeks Proposals for Integrated Countermeasure System
In a recent notice, Commerce Business Daily invited proposals to the Air Force's Wright Laboratory for the design, development, test and evaluation of a monopulse angle jamming integrated countermeasure. Reportedly, the technique being evaluated has the potential to counter certain target-tracking radars that pose threats to US Air Force aircraft. The purpose of the technique is to disable the tracking mode of the radars to prevent guided missile launch rather than counter the guided missile seeker after launch. Brassboards delivered under a contract resulting from the solicitation will be tested against both pulsed radars and pulse Doppler systems. A single contract award with a total value of $1.5 M is anticipated as a result of the solicitation. The technical effort is expected to be completed within 20 months of an award.
Army to Lead Joint Radio Development Effort
As reported in C4I NEWS, the DoD has assigned the US Army to oversee a new multimillion-dollar effort, known as the programmable modular communications system (PMCS) program. The program will develop a tactical communications system for all US services. The Army will serve as the permanent service acquisition executive for the family of tactical radios, which will meet the needs of all services. The PMCS program manager position will rotate every three years among the armed services with the Air Force assuming initial responsibility for the position. The Defense Advanced Research Project Agency and the Defense Information Systems Agency will participate in the development of the PMCS system architecture.
The PMCS approach will replace existing hardware-intensive radios with units employing software for waveform generation and processing, encryption, signal processing and other communications functions. The Army's future digital radio, the Air Force's programmable digital radio and the Navy's digital modular radio programs will all be incorporated into the PMCS effort.
Multiple contractors are expected to ultimately produce PMCS products that will use common core software and hardware modules. The PMCS effort is expected to be initiated within the next several months.
FAA Issues 1997 Commercial LEO Satellite Market Projection
The Federal Aviation Administration's (FAA) Associate Administrator for Commercial Space Transportation (AST) has issued a projection of demand for commercial low earth orbit (LEO) satellite services in the 1997 to 2006 period. Proposals for LEO satellite constellations for communications services generally fall into one of three categories. Big LEO systems operate at 1 to 2 GHz for voice and data communications, particularly mobile telephony. These systems compete with geostationary earth orbit (GEO) and terrestrial mobile telephony service providers. Little LEO systems operate below 1 GHz and provide services such as e-mail, paging and messaging typically in rural areas difficult to serve with terrestrial infrastructure. Broadband LEO systems provide high bandwidth data communications services such as video conferencing, voice and high speed data transmission. The systems use Ka-band frequencies and compete with GEO-based data relay systems.
The report lists a total of 20 communication services systems: three broadband, six big and eleven little LEO systems that are in development currently. Earliest initial launches are scheduled for 1997. In addition to these systems, two broadband, three big and four little LEO communications systems are in various stages of authorization, financing and development. The earliest initial launch expected for any of these systems is in 1998. While communication service demands remain the primary driver of LEO system development, a number of proposals exist for commercial remote sensing systems, which are in various stages of completion. The report lists six of these systems, two of which expect to launch satellites in 1997.
Under its modest growth scenario, AST expects that four big LEO constellations will be deployed and in operation by 2006. The realization of a high growth scenario would increase that number to five and add an operational broadband constellation by 2006. Two operating little LEO constellations are forecast by 2006 under AST's modest growth scenario; three constellations if its high growth model applies. AST feels that a number of proposed commercial providers of remote sensing have the resources to deploy initial systems. Assuming that demand for high resolution imagery grows as its price is reduced, AST believes that commercial remote sensing requirements could represent a secondary demand for small LEO satellites by 2006. International research organization demands for research in LEO also will add marginally to total LEO needs. For additional information, contact the Department of Transportation FAA Office of the AST at (202) 267-2937.
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