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时间:2011-01-28 16:27来源:蓝天飞行翻译 作者:admin
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system and Service lines. A single format, with jointly agreed definitions for data fields for key
reliability metrics, needs to be developed and implemented.
􀂾 Perform a cost-benefit trade study for incorporating/retrofitting some or all of the MQ-9 Predator’s
reliability enhancements into production MQ-1 Predator models.
􀂾 Perform cost-benefit trades for low and high level COTS approaches identified in Table H-3 to
improve reliability for each fielded UA system.
􀂾 Develop and implement a Reliability Specifications Standard for UA design.
Design changes can cost 1,000 and 10,000 times more at the LRIP and final production phases,
respectively, than the same change would during product design. As a result, cost increases at the early
stage (for reliability downstream) can in most cases be justified.
􀂾 Incorporate the emerging technologies identified in Table H-3 into the Defense Technology
Objectives and the Defense Technology Area Plan.
􀂾 Encourage more research into low Reynolds number flight regimes.
Just as UA come in many categories, so too do the flight environments in which they operate. As a result,
Reynolds number effects must be better understood to provide insight into such areas as (1) steady and
unsteady flow effects, (2) three-dimensional laminar/turbulent flow transition, and (3) ideal airfoil and
wing geometries at Reynolds and Mach numbers which encompass the spectrum of UA flight profiles.
Investments in low Reynolds number engine components are also critical. Turbo machinery for UA at
low speeds or high-altitudes face flight environments which are different than those to which modern
propulsion has traditionally catered. Heat rejection, turbine and compressor tip losses, and low dynamic
pressures are a few of the factors which can degrade the performance of a small propulsion system at
these low Reynolds number conditions.
􀂾 Investigate the potential role of advanced materials and structures for enhancing UA reliability and
availability.
High temperature materials and light-weight structures can offer significant weight savings for UA
airframes. On the horizon, smart materials such as shape memory alloys will offer alternatives to the
servos, flight control surfaces, and even de-icing systems of existing aircraft designs, which in turn will
reduce components count and increase reliability.
􀂾 Incorporate and/or develop all-weather practices into future UA designs.
Icing has been a primary factor in at least two Hunter mishaps and three Predator losses. UA cold
weather tolerance, as well as operation in precipitation and suboptimal wind conditions, should be a
focus for UA designers to enhance UA reliability and availability in real world operations.
Improving UA reliability is the single most immediate and long-reaching need to ensure their success.
Their current levels of reliability impact their operational utility, their acquisition costs, and their
acceptance into airspace regulations. The value of making reliability improvements must be weighed
against not only acquisition cost, as is traditionally the case, but also against the less quantifiable returns
to be gained by a commander. As a critical resource to the commander, UA must be available when they
are called upon and have the ability to operate freely and respond quickly in any airspace. The
recommendations of this study are structured to ensure that this occurs.
UAS ROADMAP 2005
UAS ROADMAP 2005
APPENDIX I – HOMELAND SECURITY
Page I-1
APPENDIX I: HOMELAND SECURITY
OVERVIEW
The Department of Homeland Security (DHS) and DoD’s Northern Command (NORTHCOM) share
responsibility for defending the United States against terrorist attacks. In addition, DHS has a number of
law enforcement functions not shared with NORTHCOM. DHS identified unmanned aircraft as a highinterest
enabler for its homeland security and law enforcement functions within months of its formation in
November 2002. In May 2003, the Secretary of Homeland Security directed a demonstration for
evaluating UA utility in border surveillance be conducted, resulting in Operation Safeguard that fall.
DHS also established an internal UA Working Group under its Border and Transportation Security (BTS)
Directorate’s Office of Science and Technology in 2003 to explore roles and define requirements that UA
could potentially fulfill throughout DHS. Its first study, Unmanned Aerial Vehicle Applications to
Homeland Security Missions (March 2004), addressed UA’s potential applicability to border security,
Coast Guard missions, critical infrastructure security, and monitoring transportation of hazardous
materials.
Subsequently, the Working Group examined the cost effectiveness of various size UA compared to that of
 
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