Eu

USAFA Discovery #2000-03 (Jul-Sep 00)

Department of Mathematical
Sciences

Ms. Deborah Arangno, has recently
accomplished research worthy of note.
The research proposed a new paradigm
for universe dynamics based on
entropy and Dirac’s radical particle
theory. The theory proposed
contradicts the current conventional
thinking that the universe is expanding
at an increasing rate by offering the
idea of transpired-event phenomenon
where time itself is accelerating.

Under this theory, the universe
would be expanding at a rate that is
getting slower and would eventually
reach an equilibrium _ state. The
research combines cosmology, physics,
and mathematics with philosophy and
theology demonstrating interesting
cross-disciplinary ties. Its abstract is
included below.

Ms Deborah Arangno

Entropy & A Paradigm Of Universe
Dynamics

Abstract for a Creationist’s View of
Cosmology

A robust theory pertaining to the
origins, dynamics, propagation, and
future of the Universe is suggested.
The radical particle theory, advanced
by P.A.M. Dirac in 1928, resulted in
the eventual discovery of certain
particles, and the evolution of
elementary particle physics.

Notably, his wave equation, the
solutions to which prompted Dirac’s
discovery of a new particle — the
positive electron, or “positron”
involved the relativistic Hamiltonian,
which is essential to our formulation of
entropy, which the author calls the
“intrinsic factor”. This paper discusses
the dynamics of the Universe, from the
generation of the first particle pair as
suggested by Dirac, to the implication
of the negative energy space, known as
the “Dirac Sea”, to the application of
the laws governing energy-matter
duality, and Peano’s space-filling curve
as a model for the propagation of
matter through the void, all within the
context of entropy, and the principle of
time-space coupling.

The scientific community is
currently misinterpreting astronomical
data to conclude the Universe is
expanding at a faster rate. Although
initially misled by these empirical
observations, cosmologists will
eventually realize that measurements —
correctly interpreted so as to account
for what the author refers to as the
transpired-event phenomenon -
indicate that time itself is that
dimension, rather than space, which is
accelerating. We will conclude,
relativistically, that the Universe is
expanding at a slower rate. The paper
discusses the dynamics of this process
and proposes that a static state must be
reached, what can be understood as an
equilibrium that must occur (taking
into account the facts concerning
relativistic relation between length
contraction and time dilation). The
paper also suggests why data may be
misconstrued to suggest the contrary.
The general dynamics of the
gravitational processes subsequent to
reaching the equilibrium event of the
Universal static state is described, and
its implications with respect to the
future of the Cosmos.

Publications and
Presentations

34th Education Group
Publications:

SMITH, J. M. “Aerospace
Professionalism Across the
Academy: Focusing on USAFA’s
Four Products.” USAFA Educator,
Fall 2000.

SMITH, J. M. ed. Searching for
National Security in an NBC World.
INSS Book Series, July 2000.

SMITH, J. M. “War Powers, Peace
Powers: Presidential Prerogative and
Military Operations Other Than
War.” National Security Studies
Quarterly, Summer 2000.

Presentations

SCHMIDT, M. D. “Iris Closure for
LCD Video Projectors.”
International Planetarium Society,
Montreal Conference, Summer 2000.

SMITH, J. M. “USAFA’s
Contribution to Aerospace
Leadership.” Executive
Commissioning Committee Meeting,
Kirtland AFB, NM, 24 July 2000.

SMITH, J. M. “Developing
Aerospace Strategists.” USAF
School of Advanced Aerospace
Studies IPT, Washington DC, 18
July 2000.

Department of Aeronautics
Publications:

GUY, Y., J. Morrow, and T.
McLaughlin. "Experimental Study of
a Delta Wing with Upper and Lower
Flaps." 18th AIAA Applied
Aerodynamics Conference, AIAA
2000-4003, August 2000.



USAFA Research Points Of Contact

To learn more about research at the United States Air Force Academy, we encourage you to visit our Web site at www.usafa.af.milidfe. If you want to focus ona
particular department or effort you might want to contact the associated Department Research Director. Each phone extension is preceded by (719)-333
commercial or 333 DSN. Each e-mail is followed by @usafa.af.mil

Phone Phone

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Editor Lt Col Alice Chen 4195 | Alice.chen Foreign Language Lt Col Rich 3201 | Richard,
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Distribution Manager_| Mr. Steve Luster 2922 | Steve.luster History Lt.Col John Shaw 4727 _| John.shaw
Managing Editor Mrs. Sanae Jones 8085 _| Sanae.jones Law Capt Jaime Sampayo | 2729 | Jaime.sampayo
Technical Editor Maj Brian Hanley 8485 | Brian.hanley Management Dr. James Barker 2315 _| Jim.barker
Cadet Summer Rsch | Capt Dave Lawyer 3080 | Dave.lawyer Mathematical Or. Kurt Herzinger 8040 | Kurt.herzinger
Sciences
34! Education Group_| Dr. Charles Krupnick 3699 _| Charles.krupnick Philosophy Or. John Hittinger 8666_|_John.hittinger
Aeronautics Dr. Aaron Byerley 3436__| Aaron.byerley Physics Maj Carl Kutsche 3412 | Carl.kutsche
Astronautics Dr. Scott Dahlke 4462 _| Scott.dahlke Political Science Or. Paul Bolt 2249 | Paul.bolt
Behavioral Sciences _| Dr. Kieth Carlson 2972 _| Kieth.carison
Biology Lt Col Tom Unangst 6015 _| Tom.unangst USAFA Research Centers
Chemistry Dr. John Wilkes 6005 | John.wilkes Aeronautics Or. Aaron Byerley 3436__| Aaron.byerley
Civil Engineering Lt Col Jim Pocock 3150_| James.pocock Aircraft Life Extension _| Lt Col Jim Greer 3618 | Jim.greer
Computer Science Maj Larry Merkle 7104__| Larry.merkle Human-Environmental_| Lt Col Rick Carrier 6016 | Rick.carrier
Economics and Geog | Dr. Jamie Harris 3068 | Jamie.harris Chemistry Dr. John Wilkes 6005 | John.wilkes
Electrical Engineering | Dr. Randall Musselman | 4211 | Randall.musselman_} Laser and Optics Dr. Randy Knize 4165 _| Randy knize
Engineering Mech Dr, Brian Self 2517 | Brian.self Small Satellite Lt Col Jerry Sellers 3315 | Jerry.sellers
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2747 _| James smith

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3978 Gary.warren

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USAFA Discovery

#2000-03 (Jul-Sep 00)

Department Research News

A twofold process integrating |

: faculty and students, teaching and |
F research will distinguish the Posvar
| Center’s programs. The centerpiece |

of these programs will be the °
endowed General Wesley W.
Posvar Chair in Political Science. i
The Center’s goal is to be a part ©
of the mainstream of the Air Force |
Academy’s cadet and academic life. |

| This will be accomplished through ©

Center-sponsored lectures, |
conferences, independent studies
and summer research projects, as
well as interaction with other |
USAFA Centers. {
Immediate goals for the Center °
include the hiring of a recognized
expert and scholar in the field of |
American and comparative defense
studies to fill the Posvar Chair. The
Center also is working on co- °
sponsoring, with the Central
Intelligence Agency, a conference
on “Intelligence: Policy and Process |
in the New Century” tentatively —
scheduled for Fall 2001. If you
would like more information on the

| Posvar Center, feel free to contact |

Lt Col Brenda Vallance in DFPS.

Department of Biology

Scanning Electron Microscopy now
available at USAFA

LtCol Edward T. Unangst, Jr. and
Dr. Michael Wilcox

On 8 September 2000, Col Klayton,
USAFA Vice-Dean, dedicated the new
USAFA scanning electron microscope
in ribbon cutting ceremonies held in
the Department of Biology.

A JEOL 2000FX  Scanning/
Transmission Electron Microscope
(STEM), retired by the Materials Lab

AFRL-WPAFB, was procured and
transported to USAFA by Dr. Mike
Wilcox and Lt Col Pat Bradshaw, DFB.
To meet strict environmental constraints,
a specially-designed room (GP133) was
constructed by 10 ABW CE through
support by both AFOSR and Brig Gen
Wagie. | With maintenance funding
provided by DF, the microscope was
brought on-line after a two-year effort.

Magnification of a fly's brain taken

with the Scanning! Transmission
Electron Microscope (STEP)

The resolution limit for this
instrument is the width of a single
carbon atom, 2.3 A. An Angstrom (A)
is 10° meters, which equates to one
ten billionth of a meter! With this
device, one can see individual atoms.
However, the real strength of the
instrument is in its analytical capability.
The device is now operational and
being used for within-institution
projects. Cadets and faculty are
currently imaging the smallest of
objects, individual atoms, and viewing
the world through 200,000 Volts.
Ideally, the microscope will be
available as government-furnished
equipment for faculty and cadets to
accomplish DoD-related research.
Examples of current and potential use
of the instrument include glaucoma
research by Dr. Wilcox and CIC Omar
Kadri, laser damage assessment by Dr.
John Obringer and C2C Jared Paslay,

C1 Omar Kadri using STEP

and biomimetics modeling of the eye

by Dr. Wilcox and CIC Tim
Lamabie. The Department of
Biology invites all prospective

researchers and faculty members to
come view the newest USAFA
technology. Only the researcher
limits its potential applications.

34th Education Group

During Summer 2000, the 34th
Education Group sponsored two
cadets for summer research. C1C
Janene L. Drummer spent six weeks
at the Air Mobility Command
Headquarters _Historian’s Office
located at Scott AFB Illinois. She
was assigned and completed her
research project, which was to create
a chronological history of the C-9A
aeromedical evacuation aircraft —
part of a series of chronologies on
aircraft in the AMC inventory. She
also had the opportunity to ride an F-
15, a C-9A, and a KC-135. CIC
Christopher G. Seaman was assigned
to the Air Force Doctrine Center at
Maxwell AFB Alabama and
participated in the development of
the new “Aerospace Commander’s
Handbook.” Both had exceptional
research and Air Force experiences
to help prepare them for their officer
careers.


USAFA Discovery #2000-03 (Jul-Sep 00)

MITCHELL, T., D. Barberis, and P.
Molton. "Experimental Studies of
Control Techniques for
Incompressible 3-D Separation and
Vortex Breakdown." AIAA
Conference Procedings, August
2000.

YECHOUT, T., T. Nettleblad, and C.

Johnston. "X-38 'Mid-Rudder' and
‘Speedbreak' Evaluation." DFAN TR
00-03, September 2000.

YECHOUT, T., C. Johnston, T.
Nettleblad, and R. Van Dyken. "X-
38 Rudder Control and Speedbrake
Performance Analysis for a Mid-
Rudder Configuration." Dept of
Aeronautics Report, September
2000.

Presentations:

BYERLEY, A., R. Butler, K. Van
Treuren, and J. Baughn. "The Effect
of Turbulence Length Scale on LPT
Blade Heat Transfer." Proc -
Minnowbrook III - Boundary Layer
Transition, Blue Mountain Lake,
NY, August 2000.

MCLAUGHLIN, T., S. Morton, J.
Morrow, and S. Siegel. "Unsteady
Computational and Experimental
Investigation of an Unmanned
Combat Air Vehicle Experiencing
Dynamic Lift." AFOSR Program
Review, Monterey, CA, September
2000.

Department of Biology
Publications:
WUNDER, B. and E. Unangst. "Use

of EM-SCAN to Determine Body
Composition in Previously Frozen

Specimens." IN: Life in the Cold, G.

Heldmaier & M. Klingenspor (eds),
Springer-Verlag Publishers.

Department of Chemistry
Publications:

YEATES, A., John S. Wilkes., and
Douglas S. Dudis. "Nonlinear
Optical Properties of the Salts of
Diffuse Anions." Proc. 45th SPIE
Conference, August 2000.

Presentations:

GAMMON, S., James F.
Blankenship, Mathew J. Sandelier,
and Ronald C. Marks.
"Implementation and Features of a
New Internet Based Homework
System." Biennial Chemical
Education Conference, Ann Arbor,
MI, July 2000.

Department of Electrical
Engineering

Publications:

MILLIGAN, M. "Implementing
COTS Opesn Systems Technology
on AWACS." CrossTalk: Journal of
Defense Software Engineering, 13/9,
September 2000.

NEAL, P. and Linda G. Shapiro. "A
Symbolic Representation for 3-D
Object Feature Detection."
International Conference on Pattern
Recognition, September 2000.

Department of History

Publications

ABADI, J. “The Quest for Foreign
Policy and National Security of
Qatar,” under review by Journal of
Mideast and South Asian Studies,
October 2000.

ABADI, J. “Ethnicity and Religion
in Israeli Politics: The Emergence of
the Shas Party.” Accepted as chapter
in edited anthology.

ABADI, J. “Constraints and
Adjustments in Portugal’s policy
toward Israel,” accepted by
International History Review.

ABADI, J. “Constraints and
Adjustments in Grecce’s Relations
with Israel,” accepted by
Mediterranean Quarterly.

ABADI, J. “Constraints and
Adjustments in Sweden’s.
Relations with Israel,” accepted by
Middle Eastern Studies.

ABADI, J. “Constraints and
Adjustments in Libya’s Relations
with Israel,” accepted by Journal of
Conflict Studies.

ABADI, J. “The Road to the
Israeli-Moroccan Rapproachment,*
accepted by Journal of North
African Studies.

ABADI, J. “Israel’s Relations with
Azerbaijan and the Muslim States
of Central Asia,” under review by
Central Asian Survey.

RUFFLEY, D.L. “Children of
Soviet Victory, Founders of
Russian Future: Young Soviet
Specialists and the Evolution of
Russian Society, 1965-1982”
Doctoral Dissertation successfully
defended at Ohio State University,
August 2000; Ph.D. degree
awarded 31 Aug 2000

Conferences
Witzel, M.D., New Faculty Boot
Camp, Leadville CO, July 2000

Department of Management

Presentations:

BARKER, J. "Writing Critical
Ethnography." Academy of
Management Convention, Toronto,
ON, August 2000.


DISTRIBUTION STATEMENT A
Approved for Public Release
Distribution Unlimited
#2000-03 (Jul-Sep 00)

USAFA Discovery is published quarterly by the faculty of the US Air Force Academy (USAFA). It contains reports on USAFA cadet and
faculty research, a complete list of current USAFA research points of contact, and a summary of recent awards and publications. All written
material contained within reflects the opinions of the authors and editors and does not necessarily reflect current US Air Force or USAFA
policy.

Research Activity in Support of Unmanned Aerial Vehicles
(UAV) at the Aeronautics Research Center

The future of air warfare is undergoing a
fundamental transformation with the move toward the
increased use of Unmanned Aerial Vehicles (UAV’s).
UAV’s are capable of performing a number of missions
in high-threat environments while minimizing the risk of
human life. An example of an important mission
particularly well suited for a UAV is the provision of
information superiority for in-theater commanders.
Information superiority is defined in Joint Vision 2010,
the official vision statement of the Joint Chiefs of Staff,
as

“the ability to collect, process, and disseminate an
uninterrupted flow of information while denying the
enemy’s ability to do the same”.

The technical breakthroughs that support UAV design
and development have taken place in the areas of
unsteady aerodynamics, controls, aerospace materials,
sensors, secure communications, and microcomputers.
Research currently underway in the Aeronautics Research
Center is adding to this important technology base.

In this issue:

« Lead article: Research Activity in Support of
Unmanned Aerial Vehicles (UAV) at the Aeronautics
Research Center (pages 1-3)

« Department Research News (page 4-5)

« Publications and Presentations (pages 5-7)

The USAF is currently operating the Predator, a
medium-altitude, medium-range, high-endurance (20
hours) UAV that was used in Kosovo to provide near-
real-time reconnaissance, target acquisition, and battle-
damage assessment. The sensors allowed for effective
operation during the day and night and in bad weather
conditions.

The USAF is currently developing the Global Hawk, a
high-altitude, aerial reconnaissance UAV. The Global
Hawk will have a maximum operating altitude of 65,000
feet and endurance of 24 hours. It will be able to provide
imagery with one-meter resolution over an area of 40,000
square nautical miles, an area roughly the size of the state
of Illinois, in one day.

ait ensure

“Predator long-endurance UA U



USAFA Discovery_ #2000-03 (Jul-Sep 00)

HORNYAK, M. "The Affective Side
of Learning." Academy of
Management National Meeting,
August 2000.

Department of Mathematical
Sciences

Publications:

WARNER, B. and J. Anderson.
"Trees, Nets, Matches and
Mushrooms." DEMS TR, 00-02, June
2000.

Presentations:

SCHOOFF, R. "The Consideration

of Multiple Objectives in US
Engagement Strategies." Int'l Conf
on Systems Engr in Decision Making,
Charlottesville, VA, June 2000.

Department of Physics
Publications:

HAALAND, R. and S. Dudley. "The
Poynting Vector and Power ina
Simple Circuit." Am. J. Physics, Vol
68, September 2000.

LE, G., W. Goedecke, C.T. Russell,
and F. Chun, "Magnetosphere on May
11, 1999, the Day the Solar Wind
Almost Disappeared." Geophysical
Research Letters, Vol 27, No 14, July
2000.

PATTERSON, E. “Just-in-Time
Teaching (JiTT)." Project
Kaleidoscope Keystone Workshop,
July 2000.

PATTERSON, E. and G. Novak.
“Chapter 2: JiTT and Physlets."
Physlets: Teaching with Interactive
Curricular Mat, August 2000.

TOMME, E., D.A. Law, B.M.
Annaratone, and J.E. Allen.
“Parabolic Plasma Sheath Potentials
and their Implications for the Charge
on Levitated Dust Particles."
Physical Review Letters, Vol 85, No
12, September 2000.

Presentations:

KRAUSE, L. "Contributions of
Undergraduate Student Space
Systems Design Courses to Progress
in Real-World Space Research:
Motivationg the Youth." AAPT
Summer Meeting, Ontario, Canada,
August 2000.

KRAUSE, L. "Instruction of Three-
Dimensional Time-Varying Systems
with Non-Immersive Virtual
Reality." AAPT Summer Meeting,
Ontario, Canada, August 2000.

KRAUSE, L., D. Knipp, B.K.
Dichter, and K.P. Ray. "The
Relationship Between DSCS III B-7
Surface Charging and Geomagnetic
Activity Indices." IEEE 2000
Nuclear and Space Rad Effects Conf,
Reno, NV, July 2000.

KRAUSE, L., D. Knipp, B. Dichter,
and K. Ray. "The Relationship
Between DSCS III Sunlight Surface
Charging and Geomagnetic Activity
Indices." IEEE 2000 Nuclear and
Space Rad Effects Conf, Reno, NV,
July 2000. .

PATTERSON, E. "Just-in-Time
Teaching (JiTT)." AAPT Summer
Meeting 2000, Guelph, Ontario, CA,
July 2000.

TAKEKOSHI, T., B. Patterson, and
R. Knize. "Optical Trapping of
Ultracold Molecules." Am. Chem.
Society 200th National Meeting,
Washington, DC, August 2000.

7
Department of Political
Science
Publications:

BOLT, P. China and Southeast
Asia's Ethnic Chinese. September
2000.

GOSE, M. “Never at War."
Contemporary Security Policy, July
2000.

HALL, G. "Be Careful What You
Ask For." International Studies
Perspectives, 1/2, August 2000.

HALL, G., S. Lambert, and J.
Cappello. "US Counterproliferation
Strategy for a New Century."
Searching for National Security in an
NBC World, September 2000.

MURRAY, D. "Leading University-
Wide Change: Defining New Roles
for the Department Chair." The
Department Chair, 11/1, August
2000.

PILCH, F. "Security and Refugees:
Dilemmas, Crises, and Debates."
Refuge: Canada's Periodical on
Refugees, 19/1, August 2000.

Presentations:

CARRESE, P. "Montesquieu and the
Spirit of Modernity." American
Political Science Association,
Washington, D.C., September 2000.

COLETTA, D. "A New Solution to
the Chain Store Paradox." American
Political Science Association,

Washington, D.C., September 2000.

MORRISON, J. "James Wilson,
Thomism, and the Founding."
American Political Science
Association, Washington, D.C.,
September 2000.



USAFA Discovery

The USAF, NASA, and the Defense
Advanced Research Projects Agency
(DARPA) are jointly developing the
Boeing X-45, the first U.S. unmanned
combat aerial vehicle (UCAV) which
is set to fly in early 2001. The UCAV,
pictured below, features _ stealth
technology and will carry multiple,
advanced, precision-guided munitions
to be used in the suppression of enemy
air defenses.

Boeing X-45a Unmanned
Combat Aerial Vebicle
USAFA UAV Research

Drag Reduction Studies on Predator
UAV

In 1998 a series of experimental
investigations to evaluate the drag-
reducing potential of several proposed
modifications to the Predator UAV
were conducted in support of the Air
Combat Command’s UAV Battle Lab.
Wind tunnel studies conducted by three
cadet teams evaluated numerous gear
and fairing configurations and
determined that the configuration with
fixed and faired main gear and a
retracted nose gear gave the best
tradeoff of low drag, low maintenance,
and minimal obstruction of sensor
fields of view. This configuration had
only slightly more drag than the current
retracted-gear _ configuration, and
offered the important advantages of
reduced actuator monitoring and
maintenance costs, plus increased
internal fuselage volume available for
sensors or fuel. The success of these
studies prompted the UAV Battle Lab
to request further landing gear studies
in FY 2001. They also asked USAFA
to study shapes for drag-reducing
fairings for Predator’s “skyball” optical
sensor turret.

#2000-03 (Jul-Sep 00)

The Predator drag-reduction studies
gave rise to questions about the
stability and control implications of
proposed modifications. Wind tunnel
tests performed by two USAFA cadets
indicated that the fixed and faired
landing gear would not cause Predator
any stability and control problems.
These studies prompted requests by the
UAV Battle Lab to study in FY 2001
the stability and control implications of
a variety of proposed external stores
for Predator.

Predator Drag Reduction
Wind Tunnel Model

Advanced UAV Design

In November 1999, the UAV Battle
Lab asked the Department of
Aeronautics aircraft design classes to
design, build, and fly two small UAV’s
suitable for use by soldiers in the field.
These small aircraft were required to
fit, when folded into a compact
configuration, into a standard
infantryman’s backpack, and to be light
enough to be carried by an average
soldier in addition to their normal field
gear and supplies. Both aircraft were
required to be deployed in total

darkness in field conditions and to
operate in near silence for 30 minutes.

ez.

“Peeping Tom" Backpack

20010328 068 ;

1wo  arferent payloads — were
specified, so that the Battle Lab could
know how payload size and weight
influences aircraft size. The first
payload was a tiny l-ounce visual
spectrum video camera and associated
downlink transmitter. The aircraft
designed to carry this payload was the
“Peeping Tom” as shown below center

The second payload was a 2-pound
infrared video camera and data
downlink, the smallest IR video system
available at the time. The aircraft
designed to carry this system was
called “ M.O.T.H.R.A” for Mobile
Over-The-Hill Reconnaissance
Aircraft. The figure below shows an

artist’s concept of MOTHRA flying
over the USAF Academy.

ca aa

Artist's Concept of
MOTHRA Backpack

Whereas the Peeping Tom was
relatively small, spanning only 28
inches and weighing less than 2
pounds, MOTHRA was significantly
larger, with a 5-foot wingspan and
weighing 5 pounds. Both aircraft were
electric powered and were constructed
of carbon fiber-epoxy skins over
styrene foam cores. At this writing, the
Peeping Tom has flown only once and
MOTHRA has not flown at all. Flight
tests of both aircraft will be performed
as part of Spring 2001 design course
requirements.

Unsteady Aerodynamics of Rapidly
Pitching UCAV

This project investigates _ the
characteristics and potential benefits



USAFA Discovery #2000-03 (Jul-Sep 00)
achieved through control of the

dynamic lift generated during a rapid
pitch-up maneuver of a generic
unmanned combat air vehicle (UCAV)
configuration pictured on the following
page.

By precisely controlling _ the
maneuver, it is possible to avoid
dynamic stall and to produce, for a
short duration, lift coefficients higher
than the static stall lift coefficient.
This increased lift can be exploited for
increased aircraft maneuverability that
can lead to increased lethality and
survivability. Because UCAV’s are
unmanned, they are particularly well
suited to such increases in
maneuverability since they can sustain
high “g” loads without human factor
concerns.

Experimental investigations are
focused on understanding the dynamic
lift due to unsteady symmetric pitch
motions and the performance benefits
gained from these maneuvers. The
program will eventually transition
these wind tunnel experiments to flight
tests. There are significant changes in
velocity during unsteady maneuvers
that cannot be duplicated correctly in a
wind tunnel, so flight-testing becomes
important. Furthermore, flight tests
eliminate wind tunnel effects due to
walls and blockage caused by the
model. In addition, the aircraft center
of rotation can change during
maneuver, leading to changes in pitch-
induced camber and __ aircraft
performance. To date the dynamic
pitch mechanism has been constructed
and successfully tested in the Low
Speed Wind Tunnel, allowing force
and moment measurements of the

UCAV model under dynamic
conditions. This effort will take
advantage of a separate UAV

Battlelab-Aeronautics Research Center
program to develop a flight control and
telemetry system for in-flight
experiments.

Computational investigations of the
UCAV are also being performed to
complement the experimental invest-

Dynamic Lift Research
Unpiloted Combat Air
Vehicle Mach 0.9

2.608901
L9s3ter01
Tsse01 fe

i Taistero | F

: rosa
Generic Unmanned Combat Air

igation of the dynamic lift phenomena.
Computational predictions provide a
view of the important — three
dimensional flowfield events that are
taking place. The fluid motion over the
UCAV can be “seen” thereby allowing
detailed analysis of the underlying flow
physics. It is the combination of
experiment, computational simulation,
and flight test that make this a unique
program.

Flight Control Laws and Flying Test
Bed

Currently an analytical =~ and
computational investigation of the
flight control laws that is particularly
well suited for small, highly
maneuverable UAV’s is underway.
This project will include the
development of a hardware-in-the-loop
UAV simulator that will allow a
“virtual” flight test using newly
developed flight control algorithms and
hardware. Finally, a radio-controlled
aircraft that will serve as a “flying
wind tunnel” UAV test bed will be
developed to support the testing of new
flow control devices such as rapidly
pitching control surfaces and pulsed jet
actuators. The on-board flight control
system will provide telemetry so that a
ground station will be able to monitor
the influence of the flow control
devices on aircraft performance.

Summary

A wide range of research activity is
currently being conducted in the
Aeronautics Research Center in support
of Unmanned Aerial Vehicles. The
research is supporting both existing
systems such as the Predator and new
systems that are being considered for
future air warfare roles such as the
“backpack UAV’s.” In addition to
applied research, the Aeronautics
Research Center is also conducting basic
research on the unsteady aerodynamic
phenomena associated with rapidly
pitching UAV’s. Finally, investigations
that involve wind tunnel experiments,
flight testing, and computational
predictions will be used to evaluate new
flow control devices to increase the
maneuverability of future UAV systems.
All of this work is adding to the
technology base supporting UAV’s while
providing cadets and faculty with

meaningful research experience and
opportunities for professional
development.

For more information, contact:

Dr. Aaron Byerley

HQ USAFA/DFAN

2354 Fairchild Drive

USAF Academy CO 80840

Aaron.Byerley@usafa.af.mil
(719) 333-3436

WESLEY W. POSVAR CENTER |
FOR AMERICAN AND
COMPARATIVE DEFENSE
STUDIES

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On 30 August 2000, the Dean of |
the Faculty formally approved the ;
establishment of the Posvar Center. |
~ The Center’s mission is: i

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To develop, sustain, and enhance ;
America’s future Air Force leaders’ +
- understanding and appreciation of |
American and comparative defense |
and national security policy through
education and research.

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