NASA Technical Memorandum 101683

STRUCTURAL DYNAMICS DIVISION RESEARCH AND

TECHNOLOGY ACCOMPLISHMENTS FOR FY 1989

AND PLANS FOR FY 1990

Jacqueline G. Smith and

James E. Gardner

January 1990

National Aeronautics and

Space Administration

Langley Research Center

Hamplon, Virginia 23665-5225

("tA_ A- [_'_- ] 0l 6°3) _T_,UCTO_AL .,_YNA_ I£ 5

DTVTSt_* _LSL^kC,_ AHO TECHNt3LOGY

ACC _FipL[,J_'-_T_ Fr_F, [-Y 1"_}9 AN& PLA_3 F_ FY

i°-_ _ (':/,SA) l':_O p CSCL OIA

0 3/0 :'

N90-15894

STRUCTURAL DYNAMICS DIVISION

RESEARCH AND TECHNOLOGY ACCOMPLISHMENTS FOR FY 1989

AND PLANS FOR FY 1990

SUMMARY

The purpose of this paper is to present the Structural Dynamics Division's

research accomplishments for FY 1989 and research plans for FY 1990. The

work under each branch (technical area) is described in terms of highlights of

accomplishments during the past year and highlights of plans for the current

year as they relate to five year plans and the objectives for each technical area.

This information will be useful in program coordination with other government

organizations, universities, and industry in areas of mutual interest.

ORGANIZATION

The Langley Research Center is organized into directorates as shown in

figure 1. Directorates are subdivided into divisions and offices. The Structural

Dynamics Division of the Structures Directorate consists of five branches as

shown in figure 2. This figure lists the key people in the division which consists

of 66 NASA civil servants and 12 members of the Army Aerostructures

Directorate, USAARTA, Army Aviation Systems Command co-located at the

Langley Research Center. Recent changes in key positions include the

appointment of Mr. Robert V. Doggett, Jr. as Assistant Chief, and the selection of

Dr. John B. Malone as Head of the Unsteady Aerodynamics Branch. Each

branch represents a technical area and disciplines under the technical areas as

shown in the figure.

The Division conducts analytical and experimental research in the five

technical areas to meet technology requirements for advanced aerospace

vehicles. The research focuses on the long range thrusts shown in figure 3.

The Configuration Aeroelasticity Branch (CAB), Unsteady Aerodynamics Branch

(UAB), and Aeroservoelasticity Branch (ASEB) all work in the area of the

prediction and control of aeroelastic stability and response of aircraft and

rotorcraft. The Landing and Impact Dynamics Branch (LIDB) conducts research

on the crash dynamics of aircraft structures and on the technology for improving

the safety and handling performance of aircraft during ground operations. The

Spacecraft Dynamics Branch (SDB) conducts research on the prediction and

control of the structural dynamic response of complex space structures.
FUNCTIONAL STATEMENT

The Division conducts analytical and experimental research in the areas

of configuration aeroelasticity, aeroservoelasticity, unsteady aerodynamics,

impact and landing dynamics, and spacecraft dynamics to meet technology

requirements for advanced atmospheric and space flight vehicles. Develops

analytical and computational methods for predicting and controlling aeroelastic

instabilities, deformations, vibrations, and dynamic response. Investigates

interaction of structure with aerodynamics and control systems, landing

dynamics, impact dynamics, and resulting structural response. Evaluates

structural configurations embodying new material systems and/or advanced

design concepts for general application and for specific classes of new

aerospace vehicles. Uses a broad spectrum of test facilities to validate

analytical and computational methods and advanced configuration and control

concepts. Develops research techniques to demonstrate safety from aeroelastic

instabilities for new airplanes, helicopters, and space launch vehicles. Test

facilities include the Transonic Dynamics Tunnel, the General Rotor Aeroelastic

Laboratory, the Impact Dynamics Research Facility, the Aircraft Landing

Dynamics Facility, the Space Structures Research Laboratory, and the Structural

Dynamics Research Laboratory.

FACILITIES

The Structural Dynamics Division has four major facilities available to

support its research as shown in figure 4.

J

The Transonic Dynamics Tunnel (TDT) is a maximum Mach 1.2

continuous flow, variable pressure wind tunnel with a 16-foot-square test section

which normally uses air or a heavy gas (R-12) as the test medium. The

maximum Reynolds number obtainable is approximately 10 million per foot in

heavy gas and 3 million per foot in air. The TDT is a unique "National" facility

that is used almost exclusively for testing of aeroelastic phenomena.

Semi-span, side-wall mounted models and full-span sting mounted or cablemounted models are used for aeroelastic studies of fixed wing aircraft. In

addition, the Aeroelastic Rotor Experimental System (ARES) test stand is used in

the tunnel to study the aeroelastic characteristics of rotors. The General Rotor

Aeroelastic Laboratory (GRAL), located in an adjacent building, is used to setup

the ARES test stand in preparation for entry into the TDT and for rotorcraft

studies in hover. The new TDT Data Acquisition System, now in full operational

use, is capable of simultaneous support of tunnel tests, GRAL tests and model

checkout in the Calibration Lab. Because of heavy gas losses to the

atmosphere as a result of deficiencies in the heavy gas reclamation system,

tunnel testing in heavy gas will be highly restricted and most testing will be

conducted in air. A major facility upgrade to improve the heavy gas reclamation

system is in progress with scheduled completion in November 1991 after which

normal operations will resume.

2
The Aircraft Landing Dynamics Facility (ALDF) is capable of testing

various types of landing gear systems at velocities up to 200 kts. on a variety of

runway surfaces under many types of simulated weather conditions. The ALDF

consists of a 2800 ft. long rail system, a 2.0 million pound thrust propulsion

system, a test carriage, and an arrestment system. Test articles can be subjected

to vertical loads up to 65,000 Ibs.or sink rate of 20 ft./sec on a wide variety of

runway surface conditions. The facility provides for testing at speeds and sizes

pertinent to large transport aircraft, fighter aircraft, and the Space Shuttle Orbiter.

The Impact Dynamics Research Facility (IDRF) is capable of crash testing

full-scale general aviation aircraft and helicopters under controlled conditions.

The facility is a 220 ft. high, 400 ft. long gantry structure which is the former Lunar

Landing Facility. General aviation aircraft and helicopters weighing up to 20,000

Ibs. can be tested up to 60 mph using a free-swinging pendulum approach or up

to 100 mph with rocket assist. Attitudes can be adjusted for desired pitch, roll,

and yaw parameters. Impact surfaces can be concrete or dirt. High speed

motion pictures and 90 data channels are available to record the crash event.

A vertical test apparatus is attached to one leg of the facility for drop-testing

structural components. The facility is used to support in-house research and

other agency programs (Army, Air Force, FAA).

The Structural Dynamics Research Laboratory (SDRL) is designed for

conducting research on the dynamic and control response of spacecraft

structures. The facilities in this laboratory include the 16 meter thermal vacuum

chamber, and the main backstop area, and the tower test area. These facilities

provide a variety of environmental simulation capabilities, including

acceleration, vacuum and thermal radiation. The chamber has a 55-foot

diameter, hemispherical dome with a 64-foot high peak, flat floor and option for a

large centrifuge or a rotating platform. Access is by an airlock door and an 18-

foot by 20-foot test specimen door. A vacuum level of 10 torr can be achieved

within 120 minutes and, with diffusion pumps, 10-4 torr vacuum can be achieved

within 160 minutes. A temperature variation of 100°F can be obtained in the

chamber by using 250-sq. ft. of portable radiant heaters and liquid nitrogen

cooled-plates. The Backstop Area is dominated by the 38-foot-high back-stop of

I-beam construction. Test areas around this fixture are 15 x 35 x 38 feet high

and a tower 12 x 12 x 95 feet high, both equipped with hydraulic and pneumatic

supply lines. There are various size hoists and accessible platforms for

suspension systems instrumentation and viewing. Closed circuit television is

available for monitoring research studies. Test articles can be excited by several

types of actuators and small shakers. State-of-the-art capability is available for

signal conditioning and processing including GenRad 2515 digital signal

processing systems and a VAX 11-780/EAI 2000 hybrid computer system for

simulation and on-line test control.

3
The Space Structures Research Laboratory (SSRL) is a large open room

of dimensions 75 x 84 x 67 feet high. It has a truss framework spanning most of

the ceiling area from which lightweight test articles can be supported. A hoist

having a capability of approximately 2 tons is available. Access is through a

12' x 12' door. A 10 x 10-foot backstop is available in one corner. A control

room equipped for structural and structural dynamics data acquisition and

analyses is available. Test equipment such as shakers, sensors, and signal

conditioning equipment is shared with the SDRL and similar closed-circuit test

monitoring and support are available.

FY 1989 ACCOMPLISHMENTS

Configuration Aeroelasticity Branch

The Configuration Aeroelasticity Branch conducts research (figure 5) to

develop the aeroelastic understanding and prediction capabilities needed to

apply new aerodynamic and structural concepts to future flight vehicles and to

determine and to solve the aeroelastic problems of current designs; to evaluate

the aeroelastic characteristics of new rotor systems; and to determine,

analytically and experimentally, effective means for predicting and reducing

helicopter vibrations. This work is more clearly identified in figure 6 which shows

the five year plan of the four disciplines and their expected results.

The Configuration Aeroelasticity FY 1989 accomplishments listed below

are highlighted in figures 7 through 22.

Aircraft Aeroelasticity:

Effects of Planform Curvature on Flutter of Swept Wing Determined in TDT

High Speed Portable System Developed For Dynamic Data

Acquisition/Analysis

Analysis of Highly Swept Delta Wing Correlates Well With Experiment

Flutter and Divergence of All-Moveable Delta Wing Determined

Aileron-Buzz Characteristics For a Generic NASP Model Are Determined

in TDT

- Open- and Closed-Loop Flutter Characteristics of Modified AFW Model

Determined in TDT

- Flutter Characteristics of a Joined-Wing High-Altitude Vehicle Determined

- F-106B Flight Envelope Flutter Cleared For Vortex Flap Experiments

Aircraft Aeroelastic Validation:

Effects of Three Tip Shapes on Wing Flutter Determined in TDT

TDT Tests Show That Ground Wind Loads Are No Problem for Atlas II

Rotorcraft Aeroelasticity:

Use of Blade Non-Structural Mass Reduces Rotorcraft Vibrations

- BVl Noise Reduced Using Higher-Harmonic Pitch Control

4
Rotorcraft Structural Dynamics:

- Significance of Warping Determined Analytically for Composite Rotor

Blades with Extension Twist Coupling

- P-Version Tapered Beam Finite Element Developed to Improve

Vibration Analyses

Ground Vibration Test of Bell All-Composite (ACAP) Airframe Conducted

as Part of Difficult Components Studies

- Anomaly Identified in Use of Damping Treatments For Reducing

Structural Vibrations

Unsteady Aerodynamics Branch

The Unsteady Aerodynamics Branch conducts research (figure 23) to

develop, validate and apply a set of computational methods for predicting steady

and unsteady aerodynamic airloads and the aeroelastic characteristics of flight

vehicles. The branch also supports research activities aimed at the generation

of experimental data bases needed for computer code validation.

Current research topics reflect a major emphasis on accurately predicting

transonic aeroelastic phenomena, such as wing "flutter-speed dip" and

aileron buzz. Additionally, research topics such as dynamic vortex-structure

interactions, dynamic loads and buffet prediction are becoming major areas of

investigation. Interest in these latter topics is due to the emerging importance of

the high angle-of-attack maneuvering flight capabilities demonstrated by a

number of current high-performance aircraft. The branch research program is

outlined in figure 24 which shows the five year plan for aerodynamic analysis

methods, aeroelastic prediction techniques and experimental investigations.

The Unsteady Aerodynamics FY1989 accomplishments listed below are

highlighted in figures 25 through 35.

Aerodynamic Analysis Methods:

Structured Grid M?thods -

Finite-Difference Mesh Design for the Transonic Small Disturbance

Equation

Unsteady Vortex-Dominated Flows Computed Using a Structured-Mesh,

Navier-Stokes Solver

Unstructured Grid Method_ -

- Adaptive Mesh Refinement Capability Developed for Accurate Vortical

Flow Computation

New Unsteady Euler Algorithm Improves Accuracy and Efficiency of

Unstructured Grid Methodology

- Temporal Adaptive Euler Method Developed for Unsteady Aerodynamic

Analysis

Graphics Code Developed to Permit Rapid Visualization of CFD Resutts

for 2-D Unstructured Meshes

5
Aeroelastic Prediction Techniques:

Structured Grid Methods-

- CAP-TSD Viscous Code Confirms Simple Criteria for Aileron Buzz

- Flutter Analysis of a Highly Swept Delta Wing with Thickness

- CFL3D Code Modified for Aeroelastic Analysis

Unstructured Grid Method_-

Euler Flutter Analysis of Airfoils Demonstrated Using Unstructured

Dynamic Meshes

Experimental Investigations:

Clipped Delta Canard Transonic Flowfield Visualized

Aeroservoelastiqity Bran¢h

The Aeroservoelasticity Branch (figure 36) conducts research to develop or

enhance methods for the modelling, analysis and synthesis of multifunctional

active control systems which have application to flexible flight and space

structures; to perform wind tunnel and flight experiments for obtaining data to

validate the new and improved methodologies; and to provide technical support

to advanced NASA and DOD flight vehicle projects for insuring that ASE

technology is available for use and that the flight envelope of the vehicle is free

of unstable aeroelastic phenomena or adverse aeroservoelastic interactions.

The scope of this work is more explicitly identified in figure 37 which shows the

five-year plan of the three major thrusts and their expected results.

The Aeroservoelasticity Branch FY 1989 accomplishments listed below are

highlighted by figures 38 through 46.

Analysis and Modelling:

- Novel Approach Developed for Determining Maximized and TimeCorrelated Gust Loads

- Nonlinear Method Predicts Static and Resultant Dynamic Aeroelastic

Behavior

Hypersonic Aeroservoelasticity Method Reduces Thermal Heating Effects

on Flutter

Control Law Synthesis:

Multilevel Method Integrates Independent Structure and Control Law

Designs

Advanced Integrated Structure/Control Design Method Improves Space

Structure System Performance

Low-Order Digital Flutter Suppression Control Laws Designed for AFW

Wind-Tunnel Model

6
Applications and Validations:

Real-Time Procedures Developed for Evaluating the Performance and

Stability of Digital, Multivariable Controllers

AFW Digital Controller Designed, Assembled, Coded, Validated and

Tested

First Active Flexible Wing Wind-Tunnel Test Successfully Completed in

the TDT

Landing and Im.Dact Dynamics Branch

The Landing and Impact Dynamics Branch (figure 47) has two major

facilities, the Aircraft Landing Dynamics Facility (ALDF) and the Impact Dynamics

Research Facility (IDRF), for conducting research. The landing dynamics group

of the branch conducts research to advance technology for safe, economical allweather aircraft ground operations including the development of new landing

gear systems. The group coordinates in-house research, grants, and contracts

with U.S. tire industry to achieve the technology required. The impact dynamics

group conducts research to obtain a better understanding of response

characteristics of generic composite aircraft components subjected to crash

loading conditions and to develop/enhance analytical tools capable of predicting

response of composite structures. In-house research, grants and contracts are

also utilized to achieve the technology and to develop better structural concepts

capable of providing energy absorption and reduced crash loads. The work of

the Landing and Impact Dynamics Branch is more clearly identified in figure 48

which shows the five-year plan of the disciplines in both landing and impact

dynamics along with their expected results. The Landing and Impact Dynamics

Branch FY 1989 accomplishments listed below are highlighted by figures 49 to

58 along with descriptive material.

Impact Dynamics:

Role of Structural Components Evaluated from Impact Response of

Graphite-Epoxy Floor Sections

Impact Scaling of Unidirectional Composite Beams Verified

Experimentally

Experimental Determination of Composite Beam Bending Stiffness

Corrects Overprediction by Lamination Theory in Large Deflection

Beam Analysis

Substantial Reductions in Tensile Strength of Fiber Composites Observed

Between Scaled Models and Full Scale Structures

DYCAST Analysis of Possible NTF Accident Scenario Matches

Post-Mishap Observations

New Analytical Sensitivity Derivatives Provide Capability to Evaluate

Lamination and Material Effects on the Vibrational Response of

Composite Fuselage Frames

7
Landing Dynamics:

Tire Analysis Codes Validated with Experimental Measurements of Space

Shuttle Nose Gear Tire

Aircraft Landing Dynamics Facility Capabilities Enhanced

Performance of F-106 Actively-Controlled Nose Gear Improved

Preliminary ALDF Test Results Define Mechanical and Friction

Characteristics of Bias-Ply, Radial-Belted, and H-Type Tires

Spacecraft Dynamics Branch

The Spacecraft Dynamics Branch conducts research (figure 59) on the

dynamics and control of advanced spacecraft. Analytical methods are

developed and verified to advance the state-of-the-art in large flexible complex

space structures such as the Space Station Freedom, earth observation

platforms and large area antennas. A major activity involving the advancement

of ground test methods for control/structure interaction is ongoing along with

laboratory upgrading necessary to accomplish this goal. The scope of this work

is more explicitly identified in figure 60 which shows the five year plan of the

organization's major thrusts and their expected results.

The Spacecraft Dynamics Branch FY 1989 accomplishments listed below

are highlighted in figures 61 through 69.

Ground Test Methods:

- Readiness of MINI-MAST CSI Testbed Facility Demonstrated

- Analytical Simulation Provides Pretest Checkout of Mini-Mast Closed

Loop Experiment

Optimal Spacecraft Performance:

- New Adaptive Modal State Estimator Provides Improved Estimator

Performance for Active Control

- Candidates Identified for Line-of-Sight Controller on a Proposed CSI

Structure

Integrated Design for Earth Pointing Satellite

Learning Control Method Developed and Applied in Flexible Panel

Slewing Analysis

Multibody Dynamics:

Reboost Analysis Developed and Utilized for Space Station Structural

Characterization Experiment

Mars Evolutionary Space Station Studies Indicate Minimal Impact on

Solar Dynamic Performance During Reboost

Space Crane Dynamics and Operations Investigated Using LATDYN

8
PUBLICATIONS

The FY 1989 accomplishments of the Structural Dynamics Division

resulted in a number of publications. The publications are listed below by

organization in the categories of journalpublications, formal NASA reports,

conference presentations, contractor reports, tech briefs, and patents.

Division Office

Journal Publications:

. Pinson, L. D.: Recent Advances in Structural Dynamics of Large Space

Structures. Acta Astronautica, Volume 19, No. 2, February 1989,

p. 161-170.

Formal NASA Reports:

. Doggett, R. V., Jr.: Some Effects of Aerodynamic Spoilers on Wing Flutter.

NASA TM-101632, July 1989.

. Doggett, R. V., Jr. and Soistmann, D. L.: Some Low-Speed Flutter

Characteristics of Simple Low-Aspect-Ratio Delta Wing Models. NASA

TM 101547, January 1989.

o Doggett, R. V., Jr.; and Soistmann, D. L.: Some Low-Speed Flutter

Characteristics of Simple Low-Aspect-Ratio Delta Wing Models. NASA

TM-101547, January 1989.

. Doggett, R. V., Jr.; Soistmann, D. L.; Spain, C. V.; Parker, E. C.; and Silva,

W.A.: Some Experimental Transonic Flutter Characteristics of Two 72 °

Sweep Delta Wing Models. NASP TM-1079, August 1989.

. Doggett, R. V., Jr.; Soistmann, D. L.; Spain, C. V.; Parker, E. C.; and Silva,

W.A.: Experimental Transonic Flutter Characteristics of Two 72 ° Sweep

Delta-Wing Models. NASA TM-101659, November 1989.

. Gardner, J. E.: Structural Dynamics Division Research and Technology

Accomplishments for FY 1988 and Plans for FY 1989. NASA TM-101543,

January 1989.

Conference Presentations:

. Doggett, R. V., Jr.; Soistmann, D. L.: Some Low-Speed Flutter

Characteristics of Simple Low-Aspect-Ratio Delta Wing Models. AIAA

Paper No. 89-1325-CP. Presented at the AIAA, ASME, et. al., 30th

Structures, Structural Dynamics and Materials Conference, April 3-5,

1989, Mobile, AL.

9
, Pinson, L. D.: NASA Space Objectives. Presented at the AIAA/AFOSR

Workshop on Microgravity Simulation in Ground Vibration Testing of

Large Space Structures, November 1989, Denver, CO.

Contractor Reports:

10. Jo&o Luiz Filgueiras de Azevedo, Stanford University, Stanford California:

Transonic Aeroelastic Analysis of Launch Vehicle Configurations.

Prepared for Langley Research Center under Grant NGL 05-020-243,

NASA CR 4186.

Confiauration Aeroelasticity Branch

Journal Publications:

11. Hinnant, H. E. and Hodges, D. H.: Nonlinear Analysis of a Cantilever

Beam. AIAA Journal. Vol. 26, No. 12, December 1988, p. 1521-1527.

12. Lakin, W. D.; and Kvaternik, R. G.: An Integrating Matrix Formulation for

Buckling of Rotating Beams Including the Effects of Concentrated Masses.

International Journal of the Mechanical Sciences, Vol. 31, No. 8,

March 1989, p. 569-577.

13. Young, M. I.: Spot Damping Anomalies. Journal of Sound and Vibration,

Vol. 131, No. 1, May 1989.

14. Young, M. I.: On Dynamic Stability Boundaries for Binary Systems.

Accepted for publication as a Letter to the Editor in the Journal of Sound

_, July 1989.

15. Young, M. I.: On Lightly Damped Linear Systems. Accepted for

publication as a Letter to the Editor in the Journal of Sound and Vibration,

November 1989.

Formal NASA Reports:

16. Brooks, T. F.; Booth, E. R., Jr.; Jolly, J. R., Jr.; Yeager, W. T., Jr., and Wilbur,

M.L.: Reduction of Blade-Vortex Interaction Noise Using Higher

Harmonic Pitch Control. NASA TM 101624 and AVSCOM TM 89-B-005,

July 1989.

17. Bruce, R. A.; Hess, R. W.; Rivera, J. A., Jr.: A Vapor Generator for

Transonic Flow Visualization. NASA TM 101670, October 1989.

18. Cole, S. R.: Flutter of a Low-Aspect-Ratio Rectangular Wing. NASA

TM 4116, June 1989.

10
19. Hinnant, H. E.: Derivation of a Tapered P-Version Beam Finite Element.

NASA TP 2931 and AVSCOM Technical Report 89-B-002, August 1989.

20. Kvaternik, R. G.; Murthy, T. S.; and Nixon, M. W. (Contributing Authors):

Integrated Multidisciplinary Optimization of Rotorcraft: A Plan for

Development. NASA TM 101617; AVSCOM TM 89-B-004, May 1989.

21. Kvaternik, R. G.: Langley Rotorcraft Structural Dynamics Program--

Background, Status, Accomplishments, Plans. NASA TM 101618, June

1989.

22. Kvaternik, R. G. and Murthy, T. S.: Airframe Structural Dynamic

Considerations in Rotor Design Optimization. NASA TM 101646, August

1989.

23. Rivera, J. A., Jr.: Experimental and Analytical Investigation of the Effect of

Spanwise Curvature on Wing Flutter at Mach Number of 0.7. NASA TM

4094, February 1989.

24. Sandford, M. C.; Seidel, D.A.; Eckstrom, C. V.; and Spain, C. V.:

Geometrical and Structural Properties of an Aeroelastic Research Wing

(ARW-2). NASA TM 4110, April 1989.

25. Wilbur, M. L.: Application of a PC Based, Real-Time, Data-Acquisition

System in Rotorcraft Wind-Tunnel Testing. NASA TM 4119 and AVSCOM

TM 89-B-003, July 1989.

Conference Presentations:

26. Cazier, F. W., Jr.; Ricketts, Rodney H.: Supersonic Transport Studies in

the Transonic Dynamics Tunnel. Presented at the High Speed Airframe

Integration Workshop, Langley Research Center, June 1989.

27. Cazier, F. W., Jr.: Understanding and Preventing Flutter. Presented at the

Experimental Aircraft Association Annual Convention in Oshkosh, WI,

August 1989.

28. Durham, M. H.; Ricketts, R. H.: Flutter of a Joined-Wing High-Altitude

Vehicle. Presented by Mike Durham at the Aerospace Flutter and

Dynamics Council Meeting, October 1989, Orlando, FL.

29. Hamouda, N.: Aeromechanical Stability. Presented at the Army

Aerostructures Directorate/NASA Rotorcraft Technology Transfer Meeting,

March 1989, Langley Research Center.

30. Hinnant, H.: P-Version Beam Finite Element Analysis. Presented at the

Army Aerostructures Directorate/NASA Rotorcraft Technology Transfer

Meeting, March 1989, Langley Research Center.

11
31. Kvaternik, R. G.: Ground Vibration Test of Helicopter Airframe Identifies

Important Contributors to Vibratory Response. Presented at the LaRC

Senior Management Research Review (SMRR), February 1989.

32. Kvaternik, R. G.: Rotorcraft Structural Dynamics Research. Presented to

visitors from ONERA and the Fluid Mechanics Institute of Marseille, May

1989, Langley Research Center.

33. Kvaternik, R. G.: Rotorcraft Structural Dynamics Research at NASA

Langley. Presented to McDonnell Douglas Helicopter Company, August

1989.

34. Lake, R.: Structural Dynamics Analysis of Composites. Presented at the

Army Aerostructures Directorate/NASA Rotorcraft Technology Transfer

Meeting, March 1989, Langley Research Center.

35. Mirick, P.: ARES Models Capabilities. Presented at the Army

Aerostructures Directorate/NASA Rotorcraft Technology Transfer Meeting,

March 1989, Langley Research Center.

36. Nixon, M.: Structural Tailoring with Composites. Presented at the Army

Aerostructures Directorate/NASA Rotorcraft Technology Transfer Meeting,

March 1989, Langley Research Center.

37. Nixon, M. W.: Analytical and Experimental Investigations of ExtensionTwist Coupled Structures. A Thesis submitted to the Faculty of The

School of Engineering and Applied Science, The George Washington

University in partial fulfillment of the requirements for the degree of Master

of Science. May 1989.

38. Ricketts, R. H.: Langley Transonic Dynamics Tunnel- A National Facility.

Presented to the George Washington University Wind Tunnel Techniques

Course, March 1989, Hampton, VA.

39. Ricketts, R. H.: Langley Transonic Dynamics Tunnel (TDT). Presented at

the OAST Wind-Tunnel Calibration Workshop, NASA Langley Research

Center, April 1989.

40. Ricketts, R. H.; Spain, V.; Parker, E.; Soistmann, D.; and Linville, T.:

Generic NASP Studies in the Langley Transonic Dynamics Tunnel.

Presented at the meeting of the Aerospace Flutter and Dynamics Council,

May 1989, Dallas, TX.

41. Ricketts, R. H.: NASA Langley Aeroelastic Models Program. Presented at

the meeting of the Aerospace Flutter and Dynamics Council, May 1989,

Dallas, TX.

12
42. Ricketts, R. H.: High-Speed Rotorcraft Aeroelasticity and Structural

Vibration. Presented at the High-Speed Rotorcraft Meeting, LaRC,

November 14, 1989.

43. Rivera, J. A., Jr.: Laser Light sheet Flow Visualization System developed

for the TDT. Presented at the LaRC Senior Management Research

Review, April 1989.

44. Soistmann, D.; Gibbons, M.: Some Analytical Transonic Flutter

Characteristics of a Highly Swept Delta Wing. Presented at the 7th NASP

Technology Symposium, October 1989, NASA Lewis Research Center.

45. Singleton, J.: Hub Design. Presented at the Army Aerostructures

Directorate/NASA Rotorcraft Technology Transfer Meeting, March 1989,

Langley Research Center.

46. Wilbur, M.: Rotor Aeroelastic Tailoring. Presented at the Army

Aerostructures Directorate/NASA Rotorcraft Technology Transfer Meeting,

March 1989, Langley Research Center.

47. Wilkie, K.: Track and Balance Studies. Presented at the Army

Aerostructures Directorate/NASA Rotorcraft Technology Transfer Meeting,

March 1989, Langley Research Center.

48. Yeager, W.: Rotor Aeroelasticity Research Overview. Presented at the

Army Aerostructures Directorate/NASA Rotorcraft Technology Transfer

Meeting, March 1989, Langley Research Center.

49. Yeager, W.: Rotor systems/Growth Blackhawk/Tailored Bearingless Rotor.

Presented at the Army Aerostructures Directorate/NASA Rotorcraft

Technology Transfer Meeting, March 1989, Langley Research Center.

50. Yeager, W. T., Jr.: Rotorcraft Aeroelasticity Overview. Presented to

visitors from ONERA and the Fluid Mechanics Institute of Marseille, May

1989, Langley Research Center.

51. Young, M. I.: On Passive Spot Damping Anomalies. Presented at the

Damping '89 Conference sponsored by the Air Force Flight Dynamics

Laboratory, February 1989, West Palm Beach, FL.

Contractor Reports:

52. Cronkhite, J. D.; Dompka, R. V.; Rogers, J. P.; Corrigan, J. C.; Perry, K. S.;

and Sadler, S. G.: Coupled Rotor/Fuselage Dynamic Analysis of the AH1G Helicopter and Correlation with Flight Vibrations Data. NASA

Contractor Report 181723, January 1989.

13
53.

54.

55.

56.

57.

58.

59.

60.

DiTaranto, R. A. and Sankewitsch, V.: Calculation of Flight Vibration

Levels of the AH-1G Helicopter and Correlation With Existing Flight

Vibration Measurements. NASA Contractor Report 181923, November

1989.

Dompka, R. V.: Investigation of Difficult Component Effects on Finite

Element Model Vibration Prediction for the Bell AH-1G Helicopter. NASA

Contractor Report 181916, Vol. 1 and Vol. II, October 1989.

Dompka, R.V.; Hashish, E.; and Smith, M. R.: GroundVibration Test

Comparisons of a NASTRAN Finite Element Model of the Bell ACAP

Helicopter Airframe. NASA Contractor Report 181775, May 1989.

Dompka, R.V.; Sciascia, M. C.; Lindsay, D. R.; and Chung, Y. T.: Plan,

Formulate, and Discuss a NASTRAN Finite Element Vibrations Model of

the Bell ACAP Helicopter Airframe. NASA Contractor Report 181774,

May 1989.

Gabel, R.; Lang, P. F.;Smith, L. A.; and Reed, D. A.: Plan, Formulate,

Discuss and Correlate a NASTRAN Finite Element Vibrations Model of

the Boeing Model 360 Helicopter Airframe. NASA CR 181787, April

1989.

Gold, Ronald R. and Reed, Wilmer H., Ill: Design of Thermoelastic

Experiments Applicable to the National Aero-Space Plane. NASP

Contractor Report 1056, August 1989.

Reed, D. A.; and Gabel, R.: Ground Shake Test of the Boeing Model 360

Helicopter Airframe. NASA CR 181766, March 1989.

Spain, C. V.; Soistmann, D. L.; and Linville, T. W.: Integration of Thermal

Effects Into Finite Element Aerothermoelastic Analysis With Illustrative

Results. NASP CR 1059. Also presented at the 6th NASP Symposium,

April 1989, Monterey, CA.

Unsteady Aerodynamics Branch

Journal Publications:

61. Batina, J. T.: Unsteady Transonic Algorithm Improvements for Realistic

Aircraft Applications. Journal of Aircraft, Volume 26, No. 2, February

1989, p. 131-139.

62. Batina, J. T.: Unsteady Transonic Small Disturbance Theory Including

Entropy and Vorticity Effects. Journal of Aircraft, Volume 26, No. 6, June

1989, p. 531-538.

14
63. Batina, J. T.; Seidel, D. A.; Bland, S. R.; and Bennett, R. M.: Unsteady

Transonic Flow Calculations for Realistic Aircraft Configurations. Journal

of Aircraft, Volume 26, No. 1, January 1989, p. 21-28.

64. Bennett, R. M.; Batina, J. T.; and Cunningham, H. J.: Wing-Flutter

Calculations with the CAP-TSD Unsteady Transonic Small-Disturbance

Program. Journal of Aircraft, Volume 26, No. 9, September 1989, p. 876-

882.

65. Edwards, J. W.; Thomas, J. L.: Computational Methods for Unsteady

Transonic Flows in AIAA Progress in Astronautics and Aeronautics

Series- Unsteady Transonic Aerodynamics, Volume 120, 1989, p. 211-

261.

66. Hess, R. W.; Seidel, D. A.; Igoe, W. B.; and Lawing, P. L.: Transonic

Unsteady Pressure Measurements on a Supercritical Airfoil at High

Reynolds Numbers. _lournal of Aircraft, Volume 26, No. 7, July 1989,

p. 605-614.

67. Seidel, D. A.; Eckstrom, C. V.; and Sandford, M. C.: Transonic Region of

High Dynamic Response Encountered on an Elastic Supercritical Wing.

,Journal of Aircraft, Volume 26, No. 9, September 1989, p. 870-875.

Formal NASA Reports:

68. Bland, S. R. (Compiler): Transonic Unsteady Aerodynamics and

Aeroelasticity - 1987. NASA CP-3022, Part 1, February 1989, 267 p.

69. Bland, S. R. (Compiler): Transonic Unsteady Aerodynamics and

Aeroelasticity - 1987. NASA CP-3022, Part 2, February 1989, 385 p.

70. Gibbons, M. D.; Soistmann, D. L.; and Bennett, R. M.:

Highly Swept Delta Wings by Conventional Methods.

November 1988, 19 p.

Flutter Analysis of

NASA TM-101530,

Conference Presentations:

71. Batina, J. T.: Application of Unstructured Grid Methods to Steady and

Unsteady Aerodynamic Problems. Presented at the Office of Aeronautics

and Space Technology NASA Computational Fluid Dynamics

Conference, March 7-9, 1989, Moffett Field, CA.

72. Batina, J. T.: Unsteady Aerodynamic Methods for Transonic Aeroelastic

Analysis. Paper No. 89-002. Presented at the European Forum on

Aeroelasticity and Structural Dynamics 1989, April 17-19, 1989, Aachen,

West Germany.

15
73.

74.

75.

76.

77.

78.

79.

Tech

80.

Batina, J. T.: Unsteady Euler Airfoil Solutions Using Unstructured

Dynamic Meshes. AIAA Paper No. 89-0115. Presented at the AIAA 27th

Aerospace Sciences Meeting, January 9-12, 1989, Reno, NV.

Batina, J. T.: Unsteady Euler Algorithm With Unstructured Dynamic Mesh

for Complex-Aircraft Aeroelastic Analysis. AIAA Paper No. 89-1189-CP.

Presented at the AIAA, ASME, et al., 30th Structures, Structural Dynamics

and Materials Conference, April 3-5, 1989, Mobile, AL.

Batina, J. T.: Vortex-Dominated Conical-Flow Computations Using

Unstructured Adaptively-Refined Meshes. AIAA Paper No. 89-1816.

Presented at the AIAA 20th Fluid Dynamics, Plasma Dynamics and

Lasers Conference, June 12-14, 1989, Buffalo, NY.

Bennett, R. M.; and Batina, J. T.: Application of the CAP-TSD Unsteady

Transonic Small Disturbance Program to Wing Flutter. Presented at the

European Forum on Aeroelasticity and Structural Dynamics 1989, April

17-19, 1989, Aachen, West Germany, Paper No. 89-003.

Gibbons, M. D.; and Batina, J. T.: Supersonic Far-Field Boundary

Conditions for Transonic Small-Disturbance Theory. Presented at the

AIAA, ASME, et al., 30th Structures, Structural Dynamics and Materials

Conference, April 3-5, 1989, Mobile, AL. AIAA Paper No. 89-1283-CP.

Rausch, R. D.; Batina, J. T.; and Yang, H. T. Y.: Euler Flutter Analysis of

Airfoils Using Unstructured Dynamic Meshes. Presented at the AIAA,

ASME, et al., 30th Structures, Structural Dynamics and Materials

Conference, April 3-5, 1989, Mobile, AL. AIAA Paper No. 89-1384-CP.

Whitlow, W., Jr.; Bennett, R. M.; and Strganac, T. W.: Analysis of

Vibrations of the National Transonic Facility Model Support System Using

a 3-D Aeroelastic Code. Presented at the AIAA 7th Applied

Aerodynamics Conference, July 31 - August 2, 1989, Seattle, WA.

AIAA Paper No. 89-2207-CP.

Briefs:

Seidel, D. A.; Batina, J. T.; and Whitlow, W., Jr.: XTRAN2L: A Program for

Solving the General-Frequency Unsteady Two-Dimensional Transonic

Small-Disturbance Equation. NASA Tech Brief LAR-13899.

Aero_ervoelasticity Branch

Journal Publications:

81. Arbuckle, P.; Buttrill, C. and Zeiler, T.: Simulation Model-Building

Procedure for Dynamic Systems Integration. AIAA Journal of Guidance,

Control, and Dynamics, p. 894-900, Nov/Dec 1989.

16
82. Gilbert, M. G.; and Silva, W. A.: The Effects of Aeroelastic Deformation on

the Unaugmented Stopped-Rotor Dynamics of an X-Wing Aircraft. AIAA

Journal of Aircraft, May 1989,Vol. 26, No. 5, p. 482-488.

83. Mukhopadhyay, V.: Digital Robust Control Law Synthesis Using

Constrained Optimization. AIAA Journal of Guidance, Control, and

Dynamics, March 1989, Vol. 12, No. 2, p. 175-181.

Formal NASA Reports:

84. Gilbert, M. G. An Analytical Sensitivity Method for Use in Integrated

Aeroservoelastic Aircraft Design, NASA TM-101583, May 1989.

85. Gilbert, G. and Schmidt, D.: Structure/Control Law Design by Multilevel

Optimization. NASA-TM 101623, June 1989.

86. Mukhopadhyay, V.; Perry, B., III; and Noll, T. E.: Flutter Suppression

Control Law Synthesis for the Active Flexible Wing Model, NASA TM101584, May 1989.

87. Noll, T. E.; Perry, B, Ill; and Gilbert, M. G.: Recent Activities in

Aeroservoelasticity at the NASA Langley Research Center, NASA TM101582, May 1989.

88. Noll, T. E.; Perry, B., III; Tiffany, S. H.; et. al.: Aeroservoelastic WindTunnel Investigations Using the Active Flexible Wing Model - Status and

Recent Accomplishments, NASA TM- No. 89-101570, April 1989.

89. Perry, B., III; Pototzky, A. S.; Woods, J. A.: An Investigation of the

"Overlap" Between the Statistical Discrete Gust and the Power Spectral

Density Analysis Methods, NASA TM-101571, April 1989.

90. Pototzky, A. S.; Zeiler, T. A.; and Perry, B., II1: Time-Correlated Gust Loads

Using Matched-Filter Theory and Random-Process Theory - A New Way

of Looking at Things, NASA TM-101573, April 1989.

91. Tiffany, S. H.; and Karpel, M.: Aeroservoelastic Modeling and

Applications Using Minimum-State Approximations of the Unsteady

Aerodynamics, NASA TM-101574, April 1989.

92. Woods, J. A.; Gilbert, M. G.; and Weisshaar, T. A.: Results of a Parametric

Aeroelastic Stability Analysis of a Generic X-Wing Aircraft, NASA TM101572, April 1989.

93. Zeiler, T. A.; and Wieseman, C. D.: Aeroelastic Modeling for the FIT Team

F/A-18 Simulation, NASA TM-101569, March 1989.

17
Conference Presentations:

94. Gilbert, M. G.: An Analytical Sensitivity Method for Use in Integrated

Aeroservoelastic Aircraft Design. Presented at the European Forum on

Aeroelasticity and Structural Dynamics, April 1989, Aachen, Federal

Republic of Germany.

95. Gilbert, M. G.: Research in Aeroservoelasticity at NASA Langley

Research Center. Presented at the Aerospace Flutter and Dynamics

Council Meeting, October 1989, Orlando, FL.

96. Gilbert, M. G.; Pototzky, A.; Heeg, J.; Dunn, J.; Spain, V. and Soistmann,

D.: The Application of Active Controls Technology to a Generic

Hypersonic Aircraft Configuration. Presented at the NASP Fall

Symposium, October 1989.

97. Gilbert, M. G. and Schmidt, D.: Structure/Control Law Design by

Multilevel Optimization. Presented at the AIAA Guidance, Navigation, and

Control Conference, August 1989, Boston, MA.

98. Liu, D. D.; Chen, P. C.; Pototzky, A. S.; and James, D. K.: Further Studies

of Harmonic Gradient Method for Supersonic Aeroelastic Applications.

Presented at the European Forum on Aeroelasticity and Structural

Dynamics, April 1989, Aachen, Federal Republic of Germany.

99. Mukhopadhyay, V.; Perry, B., III; and Noll, T. E.: Flutter Suppression

Control Law Synthesis for the Active Flexible Wing Model. Presented at

the European Forum on Aeroelasticity and Structural Dynamics, April

1989, Aachen, Federal Republic of Germany.

100. Mukhopadhyay, V.; Perry, B., III; and Noll, T. E.: Flutter Suppression

Control Law Synthesis for the Active Flexible Wing. May 1989.

Presented at the Seventh VPI&SU Symposium on Dynamics and Control

of Large Structures, May 1989, Blacksburg, VA. Manuscript in symposium

proceedings.

101. Mukhopadhyay, V.; Perry, B.; and Noll, T.: A Multiloop, Digital Flutter

Suppression Control Law Synthesis Case Study. Presented at the AIAA

Guidance, Navigation, and Control Conference, August 1989, Boston,

MA.

102. Noll, T.. E.; Gilbert, M. G.; and Perry, B., II1: Development and Validation of

Aeroservoelastic Design Methodologies at the NASA Langley Research

Center. Presented at the Seventh VPI&SU Symposium on Dynamics and

Control of Large Structures, May 1989, Blacksburg, VA. Manuscript in

symposium proceedings.

18
103.

104.

105.

106.

107.

108.

109.

110.

111.

NolI, T. E.; Perry, B., III; and Gilbert, M.: Aeroservoelasticity, Current

Trends and Future Expectations. Presented at the Australian

Aeronautical Conference, October 1989, Melbourne, Australia.

Noll, T. E.; Perry, B., III; and Gilbert, M. G.: Recent Activities in

Aeroservoelasticity at the NASA Langley Research Center. Presented at

the European Forum on Aeroelasticity and Structural Dynamics, April

1989, Aachen, Federal Republic of Germany.

Noll, T. E.; Perry, B., III; Tiffany, S. H.; et. al.: Aeroservoelastic WindTunnel Investigations Using the Active Flexible Wing Model - Status and

Recent Accomplishments. AIAA Paper No. 89-1168. Presented at the

AIAA Structures, Structural Dynamics and Materials Conference, April

1989, Mobile, AL.

Perry, B., III; Pototzky,A. S.; Woods, J. A.: An Investigationof the

"Overlap" Between the Statistical Discrete Gust and the Power Spectral

Density Analysis Methods. AIAA Paper No. 89-1376. Presented at the

AIAA Structures, Structural Dynamics and Materials Conference, April

1989, Mobile, AL.

Perry, B., Ill: Similarity Between Time-Correlated Gust Loads Computed

Using Matched Filter Theory, Random Process Theory, and the Statistical

Discrete Gust Method. Presented at the Aerospace Flutter and Dynamics

Council Meeting, May 1989, Dallas, TX.

Perry, B., III; Woods, J. A.; and Pototzky, A. S.: NASA Investigation of the

SDG-PSD Overlap with Emphasis on "Method 2" of the SDG Method.

Presented at the Gust Specialists Meeting, April 1989, Mobile, AL.

Pototzky,A. S.; Perry, B., III; Woods, J. A.; and Zeiler, T. A.: Similarity

Between Time-Correlated Gust Loads Computed Using Matched Filter

Theory and the Statistical Discrete Gust Method. Presented at the Gust

Specialists Meeting, April 1989, Mobile, AL.

Pototzky, A. S.; Zeiler, T. A.; and Perry, B., II1: Time-Correlated Gust Loads

Using Matched-Filter Theory and Random-Process Theory - A New Way

of Looking at Things. AIAA Paper No. 89-1374. Presented at the AIAA

Structures, Structural Dynamics and Materials Conference, April 1989,

Mobile, AL.

Tiffany, S. H.; and Karpel, M.: Aeroservoelastic Modeling and

Applications Using Minimum-State Approximations of the Unsteady

Aerodynamics. AIAA Paper No. 89-1188. Presented at the AIAA

Structures, Structural Dynamics and Materials Conference, April 1989,

Mobile, AL.

19
112. Woods, J. A.; Gilbert, M. G.; and Weisshaar, T. A.: Results of a Parametric

Aeroelastic Stability Analysis of a Generic X-Wing Aircraft. AIAA Paper

No. 89-1385. Presented at the AIAA Structures, Structural Dynamics and

Materials Conference, April 1989, Mobile, AL.

113. Wieseman, C. D.: Methodology for Using Steady Experimental

Aerodynamic Data to Improve Steady and Unsteady Aerodynamic

Analysis. Master's thesis submitted to the George Washington University,

February 1989.

114. Zeiler, T. A.; and Pototzky, A. S.: On the Relationship Between Matched

Filter Theory as Applied to Gust Loads and Phased Design Loads

Analysis. Presented at the Gust Specialists Meeting, April 1989,

Mobile, AL.

Contractor Reports:

115. Zeiler, T. A.; Pototzky, A. S.: On the Relationship Between Matched Filter

Theory as Applied to Gust Loads and Phased Design Loads Analysis,

NASA CR 18102, April 1989.

Landing and Impact Dynamiq8 Branch

Formal Reports:

116. Carden, H. D.; Fasanella, E. L.; and Jones, L.. E.: Analysis of the Space

Shuttle Orbiter Skin Panels under Simulated Hydrodynamic Loads.

NASA TM-4082, December 1988.

117. Fasanella, E. L.; Jones, L. E.; and Carden, H. D.: Interim Transportation

Overpack Container (ITOC) Experiments and Analysis. NASA TM101510, October 1988.

118. Jackson, K. E. and Fasanella, E. L.: Scaling Effects in the Static Large

Deflection Response of Graphite-Epoxy Composite Beams. NASA TM101619, AVSCOM TM-89-B-006, June 1989.

119. Jones, L. E.; and Carden, H. D.: Evaluation of Energy Absorption of New

Concepts of Aircraft Composite Subfloor Intersections. NASA TP-2951,

November 1989.

120. Noor, A. K. and Kim, K. O.: Mixed Formulation for Frictionless Contact

Problems. NASA TP-2897, April 1989.

121. Noor, A. K.; Peters, J. M.; and Min, B. J.: Mixed Finite Element Models for

Free Vibrations of Thin-Walled Beams. NASA TP-2868, February 1989.

20
122. Yager, T. J.; Vogler, W. A.; and Baldasare, P.: Evaluation of Two

Transport Aircraft and Several Ground Test Vehicle Friction

Measurements Obtained for Various Runway Surface Types and

Conditions - A Summary of Test Results From Joint FAA/NASA Runway

Friction Program. NASA TP-2917, December 1989.

Journal Articles:

123. Noor, A. K. and Kim, K. O.: Mixed Formulation for Frictionless Contact

Problems. Finite Elements in.Analysis and Design, Vol. 4, 1989, p. 315-

332.

124. Noor, A. K.; Kim, K. O.; and Tanner, J. A.: Analysis of Aircraft Tires Via

Semianalytic Finite Elements. Finite Elements in Analysis and Design,

August 1989.

125. Yager, T. J.: The Joint FAA/NASA Aircraft/Ground Vehicle Runway

Friction Program. Flight Safety Digest. March 1989, p. 1-6.

Conference Presentations:

126. Boitnott, R. L.and Fasanella, E. L.: Impact Evaluation of Composite Floor

Sections. SAE Paper No. 891018. Presented at the SAE General

Aviation Aircraft Meeting and Exposition, April 1989, Wichita, KS.

127. Boitnott, R. L. and Kindervater, C.: Crashworthy Design of Helicopter

Composite Airframe Structures. Presented at the 15th European

Rotorcraft Forum, September 1989, The Netherlands.

128. Daugherty, R. H. and Stubbs, S. M.: Spin-Up Studies of the Space

Shuttle Orbiter Main Gear Tire. SAE Paper No. 881960. Presented at

SAE Meeting AeroTech'88, October 1988, Anaheim, CA.

129. Daugherty, R. H. and Stubbs, S. M.: Orbiter Post-Tire Failure and Skid

Testing Results. SAE Paper No. 892338. Presented at SAE Meeting

AeroTech'89, September 1989, Anaheim, CA.

130. Daugherty, R. H.; Yager, T. J.; and Stubbs, S. M.: Shuttle Landing

Runway Modifications to Improve Tire Spin-Up Wear Performance. SAE

Paper No. 881402. Presented at SAE Meeting AeroTech'88, October

1988, Anaheim, CA.

131. Davis, P. A. and Stubbs, S. M.: Shuttle Orbiter Arrestment System

Studies. SAE Paper No. 881363. Presented at SAE Meeting

AeroTech'88, October 3-6, 1988, Anaheim, CA.

21
132. Davis, P. A., Stubbs, S. M.; and Vogler, W. A.: Cornering and Wear

Characteristics of the Space Shuttle Orbiter Nose-Gear Tire. SAE Paper

No. 892347. Presented at SAE Meeting AeroTech'89, September 25-28,

1989, Anaheim, CA.

133. Jackson, K. E. and Fasanella, E. L.: Scaling Effects in the Static Large

Deflection Response of Graphite-Epoxy Beams. Presented at the AHS

National Technical Specialists' Meeting on Advanced Rotorcraft

Structures, October 1988, Williamsburg, VA. In Proceedings.

134. Jackson, K. E. and Fasanella, E. L.: Scaling Effects in the Impact

Response Graphite-Epoxy Composite Beams. SAE Paper No. 891014.

Presented at the SAE General Aviation Aircraft Meeting and Exposition,

April 1989, Wichita, KS.

135. Kim, K. O.; Tanner, J. A.; and Noor, A. K.: Frictionless Contact of Aircraft

Tires. SAE Paper No. 892350. Presented at SAE Meeting AeroTech'89,

September 1989, Anaheim, CA.

136. Lopez, M. C.; Davis, P. A.; Vogler, W. A.; and Yeaton, R. B.: Fore-and-Aft

Stiffness and Damping Characteristics of 30 x 11.5-14.5, Type VIII, BiasPly and Radial-Belted Aircraft Tires. SAE Paper No. 881357. Presented

at SAE Meeting AeroTech'88, October 1988, Anaheim, CA.

137. Yager, T. J.: A Summary of Recent Aircraft/Ground Vehicle Friction

Measurement Tests. SAE Paper No. 881403. Presented at SAE Meeting

AeroTech'88, October 1988, Anaheim, CA.

138. Yager, T. J.: Aircraft and Ground Vehicle Friction Measurements Obtained

under Winter Runway Conditions. SAE Paper No. 891070. Presented at

the SAE General Aviation Aircraft Meeting and Exposition, April 1989,

Wichita, KS.

139. Yager, T. J.: Aircraft Radial-Ply Tire Friction Performance. Presented at

the 1989 Clemson University Tire Industry Conference, October 1989,

Greenville, SC.

140. Yager, T. J. and Vogler, W. A.: Current Status of Joint FAA/NASA Runway

Friction Program. SAE Paper No. 892340. Presented at SAE Meeting

AeroTech'89, September 1989, Anaheim, CA.

Technical Talks:

141. Davis,P. A.: Static Mechanical Properties of 30 x 11.5-14.5, Type VIII

Bias-Ply and Radial-Belted Aircraft Tires. Presented at the Tire

Conference, October 1988, Greenville, SC.

22
142.

143.

144.

145.

146.

147.

148.

149.

150.

151.

152.

Davis, P. A. and Lopez, M. C.: Stiffness and Damping Characteristics of

Bias-Ply and Radial-Belted 30 x 11.5-14.5, Type VIII Aircraft Tires.

Presented at the Tire Society Eighth Annual Meeting and Conference on

Tire Science and Technology, March 21-22, 1989,Akron, OH.

Lopez, M. C." Overview of NASA Research Activities Supporting the

National Tire Modeling Program. Presented at the National Tire Modeling

Technical Meeting, March 20, 1989, Akron, OH.

Stubbs, S. M.: Spin-Up Wear Studies of the Space Shuttle Orbiter Main

Gear Tire. Presented at the Southern Rubber Group Conference on

Polymer Applications in Space, February 9-10, 1989, Huntsville, AL.

Yager, T. J.: An Overview of Joint FAA/NASA Runway Friction Program.

Presented at the Runway Friction Workshop, October 1988, NASA

Langley Research Center.

Yager, T. J.: Aircraft Test Results - NASA Evaluation. Presented at the

Runway Friction Workshop, October 1988, NASA Langley Research

Center.

Yager, T. J.: Ground Vehicle Test Results. Presented at the Runway

Friction Workshop, October 1988, NASA Langley Research Center.

Yager, T. J." Aircraft/Ground Vehicle Tire Friction Relationships - NASA

Assessment. Presented at the Runway Friction Workshop, October 1988,

NASA Langley Research Center.

Yager, T. J.: An Overview of NASA Langley's Aircraft Landing Dynamics

Research Program. Presented at the National Transportation Safety

Board's Transportation Safety Workshop - Commercial Aviation, February

1989, Washington, DC.

Yager, T. J.: NASA/FAA Runway Friction Measurements - Current Status

and Future Plans. Presented at the 23rd Annual International Snow

Symposium of Northeast Chapter, American Association of Airport

Executives, April 1989, Buffalo, NY.

Yager, T. J.: NASA/FAA Runway Friction Measurements - Current Status

and Future Plans. Presented at the NASAO/CARE Third Annual

International Airport Pavement Management Symposium, April 1989,

Dallas,TX.

Yager, T. J.: NASA/FAA Runway Friction Measurements- Current Status

and Future Plans. Presented at the 6th Biennial SWIFT Workshop, June

1989, Brandon, Canada.

23
153.

Tech

154.

Yager, T. J.; Davis, P. A.; and Stubbs, S. M.: Friction Performance of

Radial-Ply Aircraft Tires. Presented at SAE Meeting AeroTech'89,

September 1989, Anaheim, CA.

Briefs

Daugherty, R. H.; and Stubbs, S. M.: Measurement of Flow Rate and

Trajectory of Tire-Generated Water Spray. NASA Tech Brief LAR-14030.

Spacecraft Dynamics Branch

Journal Publications:

155. Belvin, K. W.; Edighoffer, H. H.; and Herstrom, C. L.: Quasistatic Shape

Adjustment of A 15-Meter-Diameter Space Antenna. Journal of

Spacecraft and Rockets, May 1989.

156. Gawronski, W. and J. N. Juang: Model Reduction for Flexible Structures,

Control and Dynamic Systems, Advanced in Theory and Applications,

Edited by C. T. Leondes, Academic Press, Inc., New York.

157. Huang, J-K.; Juang, J-N.; Chen, C-W.: Single-Mode Projection Filters for

Modal Parameter Identification for Flexible Structures. Journal of

Guidance. Control and Dynamics, Volume 12, No. 4, July-August 1989,

p. 569-576.

158. Juang, J. N., L. G. Horta, and R. W. Longman: Input/Output System

Identification: Learning from Repeated Experiments, Mechanics and

Control of Large Space Structures, AIAA Progress Series Volume. Edited

by J. L. Junkins.

1 59. Juang, J-N.; Lim, K. B.; and Junkins, J. L.: Robust Eigensystem

Assignment for Flexible Structures. Jovrnal of Guidance. Control and

Dynamics, Vol. 12, No. 3, May 1989, p. 381-387.

1 60. Juang, J. N., and Maghami, P. G.: Robust Eigensystem Assignment for

Second Order Dynamical Systems, Mechanics and Control of Large

Space Structures, AIAA Progress Series Volume, Edited by J. L. Junkins.

161. Lim, K. B.; Juang, J-N.; and Ghaemmaghami, P.: Eigenvector Derivatives

of Repeated Eigenvalues Using Singular Value Decomposition. Journal

of Guidance. Control. and Dynamics. Vol. 12, No. 2, March-April 1989,

p. 282-283.

162. McGowan, P. E. and Housner, J. M.: Nonlinear Dynamic Effects in the

Slewing of Flexible Space Booms During Deployment. J0_rnal of

Computational Methods. Vol. 5., July 1989.

24
163. Rew, D. W.; Junkins, J. L.; and Juang, J-N.: Robust Eigenstructure

Assignment by a Projection Method: Applications Using Multiple

Optimization Criteria. Journal of Guidance, (_0n'(roI and Dynamics,

Vol. 12, No. 3, May 1989, p. 396-403.

164. Williams, T.: Computing the Transmission Zeros of Lusage Space

Structures. IEEE Transactions on Automatic Control. Vol. 34, No. 1,

January 1989, p. 92-94.

Formal NASA Reports:

165. Belvin, W. K.; and Park, K. C.: On the State Estimation of Structures with

Second Order Observers. NASA TM-101602, May 1989.

166. Birchenough, S. A.: Analysis and Test of a 16-Foot Diameter Radial Rib

Reflector Developmental Model. NASA TM-101648, August 1989.

167. Lim, K. B.; Juang, J.-N.; and Maghami, P.: A Study on the Sensitivity and

Simultaneous Adjustment of a Hoop-Column Antenna Surface. NASA

TM-101538, January 1989.

168. Smith, S. W., and McGowan, P. E.: Locating Damaged Members in a

Truss Structure Using Modal Data: A Demonstration Experiment, NASA

TM-101595, April 1989.

Conference Presentations:

169. Anderson, M. S.: Transient Response of Lattice Structures Based on

Exact Member Theory. Presented at the AIAA/ASME/ASCE/AHS 30th

Structures, Structural Dynamics and Materials Conference, April 1989,

Mobile, AL.

1 70. Belvin, W. K.; and Park, K. C.: Computational Architecture for Integrated

Controls and Structures Design. Presented at the Third Annual

NASA/DOD CSI Conference. January 1989, San Diego, CA.

171. Belvin, W. K.; and Park, K. C.: On the State Estimation of Structures with

Second Order Observers. AIAA No. 89-1241. Presented at the 30th

AIAA/ASME/ASCE/AHS Structures, Structural Dynamics and Materials

Conference, April 1989, Mobile, AL.

172. Belvin, W. K.: Simulation and Interdisciplinary Design Methodology for

Control Structure Interaction Systems. Ph.D. Dissertation, University of

Colorado, July 1989.

173. Bergmann, M.; Longman, R.; Juang, J-N.: Variance and Bias

Computation for Enhanced System Identification. Presented at the 28th

IEEE Conference on Decision and Control, December 13-1 5, 1989,

Tampa, FL.

25
174.

175.

176.

177.

178.

179.

180.

181.

182.

183.

Gawronski, W. K.; and Williams, T.: Modal and Balanced Reduction of

Vibrating Systems. Proceedings of the 30th AIAA/ASME/ASCE/AHS/ASC

Structures, Structural Dynamics and Materials Conference, April 1989,

Mobile, AL.

Gronet, M. J.; Crawley, E. F.; and Allen, B. R.: Design, Analysis and

Testing of a Hybrid-Scale Structural Dynamic Model of a Space Station.

AIAA No. 89-1340-CP. Presented at the 30th AIAA/ASME/ASCE/

AHS/ASC Structures, Structural Dynamics and Materials Conference,

April 1989, Mobile, AL.

Hanks, B. R.: Controls-Structures Interaction: An Interdisciplinary

Challenge. Presented at the 35th American Astronautical Society

Symposium, October 1988, St. Louis, MI.

Housner, J. M.; Chang, C. W.; and Wu, S-C.: Controlled Multibody

Dynamics Simulation for Large Space Structures. Presented at the Third

Annual NASA/DOD CSi Conference, January 1989, San Diego, CA.

Juang, J-N.; Horta, L. G.; and Longman, R. W.: System Identification in the

Repetition Domain. AAS/AIAA Astrodynamics Specialist Conference,

August 7-10, 1989.

Juang, J-N.; and Wright, J. R.: A Multi-Point Force Appropriation Method

Based Upon a Singular Value Decomposition Approach. Presented at

the 7th International Modal Analysis Conference, January 1989, Las

Vegas, NV.

Juang, J-N.; Yang, L-F.; and Huang, J-K.: Lyapunov-Based Control

Design for Flexible Manipulators. Presented at the 30th

AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and

Materials Conference, April 1989, Mobile, AL.

Juang, J-N.; Yang, L-F.; Huang,J-K.; Macanley, R.: Rapid

Rotational/Translational Maneuvering Experiments of a Flexible Steel

Beam. Presented at the AIAA, AIChE, et. al., 1989 American Control

Conference, June 21-23, 1989, Pittsburgh, PA. In Proceedings.

Kienholz, D. A.; Crawley, E. F.; and Harvey T. J.: Very Low Frequency

Suspension Systems for Dynamic Testing. AIAA No. 89-1194-CP.

Presented at the 30th AIAA/ASME/ASCE/AHS/ASC Structures, Structural

Dynamics and Materials Conference, April 1989, Mobile, AL.

Longman, R. W.; and Horta, L. G.: Actuator Placement by Degree-ofControllability Including the Effect of Actuator Weight. Presented at the

7th VPI&SU Symposium on Dynamics and Control Large Structures. May

1989, Blacksburg, VA.

26
184.

185.

186.

187.

188.

189.

190.

191.

192.

Maghami, P. G.; and Juang, J-N.: Efficient Eigenvalue Assignment for

Large Space Structures. Presented at the 30th AIAA/ASME/ASCE/

AHS/ASC Structures, Structural Dynamics and Materials Conference,

April 1989, Mobile, AL.

Maghami, P. G.; Juang, J-N.; and Lim, K. B.: On Eigensystem Assignment

with Output Feedback. Presented at the AIAA Guidance, Navigation, and

Controls Conference, August 1989, Boston, MA.

McGowan, P. E.; Edighoffer, H. H.; Wallace, J. W.: Development of an

Experimental Space Station Model for Structural Dynamics Research.

Presented at the 60th Shock and Vibration Symposium, November 1989,

Virginia Beach, VA.

Newsom, J. R.; and Hanks, B. R.: Controls-Structures Interaction

Research at the NASA Langley Research Center. Presented at the

European Forum on Aeroelasticity and Structural Dynamics, April 1989,

Aachen, West Germany.

Park, K. C.; and Belvin, W. K.: Stability and Implementation of Partitioned

CSI Solution Procedures. AIAA No. 89-1238, Presented at the 30th

AIAA/ASME/ASCI/AHS Structures, Structural Dynamics and Materials

Conference, April 1989, Mobile, AL.

Smith, S. W.; and Beattie, C.A.: Secant-Method Matrix Adjustment for

Structural Models. Presented at the AIAA/ASME/ASCE/AHS/ASC 30th

Structures, Structural Dynamics, and Materials Conference, April 1989,

Mobile, AL.

Smith, S. W.; and McGowan, P. E.: Locating Damaged Members in a

Truss Structure Using Modal Test Data: A Demonstration Experiment.

AIAA Paper No. 89-1291. Presented at the 30th AIAA/ASME/ASCE/

AHS/ASC Structures, Structural Dynamics and Materials Conference,

April 1989, Mobile, AL.

Sparks, D. W. Jr; Homer, G. C.; Juang, J-N.; and Klose, G.: A Survey of

Experiments and Experimental Facilities for Active Control of Flexible

Structures, Presented at the Third Annual NASA/DOD CSI Conference,

January 1989, San Diego, CA.

Sparks, D. W. Jr.; and Juang, J-N.: A Survey of Experiments and

Experimental Facilities for Active Control of Flexible Structures.

Presented at the AIAA Guidance, Navigation and Control Conference,

August 1989, Boston, MA.

27
193. Woodard, S. E.; and Cooley, V. M.: NASA CSI Suspension Methods

Overview. Presented at the Third Annual NASA/DOD CSI Conference,

January 1989, San Diego, CA.

194. Wu, S-C; Chang, C-W; and Housner, J. M.: Dynamic Analysis of Flexible

Mechanical Systems Using LATDYN. Presented at the 3rd Annual

Conference on Aerospace Computational Control, August 1989,

Oxnard, CA.

FY 1990 PLANS

The FY 1990 plans for the Structural Dynamics Division are broken out by

each of the branches (technical areas) and selected highlights of proposed FY

1990 milestones are presented.

Configuration Aeroelasticity Branch

Figure 70 summarizes accomplishments planned for FY 1990 selected

from the Branch's broad based research program on dynamic and aeroelastic

phenomena of aircraft and rotorcraft.

A large portion of this work is associated with wind-tunnel tests in the

Langley TDT with companion theoretical studies. Research studies are planned

for both aircraft and rotorcraft. Aircraft studies will include further flutter

clearance testing of the Navy A-12 for the Department of Defense, additional

flutter investigations in support of the HSCT effort, and several investigations in

support of the NASP program.

Basic studies related to aircraft will include testing of a NACA 0012 rectangular

wing on a flexible mount to provide flutter data and a limited amount of

corresponding unsteady pressure data and an investigation into coupling of

periodic aerodynamic oscillations with structural modes.

The rotorcraft aeroelasticity work will include testing of a new design

hingeless rotor. Initial tests will also be conducted on ARES second generation

testbeds. Research studies in rotorcraft structural dynamics are aimed at

developing advanced finite element-based dynamics analysis methods for

predicting airframe vibrations, with particular emphasis on developing

computational procedures for application in airframe dynamics design work. Inhouse studies and studies by the major airframe manufacturers and universities

will be pursued in such areas as airframe finite element modeling, dynamics of

coupled rotor-airframe systems, and airframe structural optimization under

vibration constraints. In addition, work will continue toward demonstrating the

potential of extension-twist coupling for passively controlling blade twist for

improved aerodynamic performance of tiltrotor aircraft.

Highlights of proposed FY 1990 research for the four technical areas of

Aircraft Aeroelasticity, Aircraft Aeroelastic Validation, Rotorcraft Aeroelasticity,

and Rotorcraft Structural Dynamics are shown in figures 71 through 74.

28
Aircraft Aeroelasticity:

- Aircraft Aeroelasticity

Aircraft Aeroelastic Validation:

-Aircraft Aeroelastic Validation

Rotorcraft Aeroelasticity:

- Rotorcraft Aeroelasticity

Rotorcraft Structural Dynamics:

- Rotorcraft Structural Dynamics

Unsteady Aerodynamics Branch

For FY 1990 there will be continuing activity in developing computational

methods to solve nonlinear, unsteady fluid flow equations for application to

aeroelastic analysis (figure 75). There will be continued applications of the

CAP-TSD code to aeroelastic response problems in order to further define its

range of accuracy. As part of this activity, the branch will continue to provide

support for the CAP-TSD code via a contract programmer. In addition, flutter and

aeroelastic response calculations will be performed using higher-order methods,

such as solution procedures based on the Euler and Navier-Stokes

equations.Correlations of Euler/Navier-Stokes numerical results with potential

equation solutions and experimental data will further delineate appropriate

regions for use of the various flow solvers. This year will also see key

developments in the field of vortex and viscous dominated flows and their roles

in aeroelastic response phenomena known to occur on high-performance

aircraft. These research efforts with higher-order CFD methods will be carried

out using both structured and unstructured grid flow solvers. Finally, a new

initiative in FY1990 will be the development of an in-house capability to

generate computational grids for use with both structured and unstructured grid

CFD procedures.

Aerose rvoelasticity Branch

Figure 76 lists the major tasks being pursued by the Aeroservoelasticity

Branch in FY 1990. In the Analysis and Modeling area, the focus of attention

involves the development of procedures for using nonlinear transonic

aerodynamics represented as Volterra series for ASE applications. In addition,

means of approximating aerodynamics in the time domain rather than the

Laplace domain are also being investigated to improve our ASE analysis and

design methodologies. Studies to evaluate the effects of temperature

distributions and thermal stresses and gradients on the aeroelastic

characteristics of generic hypersonic vehicles will continue. Various active

control concepts which offer the potential for improving the loss of aircraft

stability or performance due to thermal effects will be investigated. In the Control

Law Synthesis area, the design procedures developed for obtaining low-order,

29
MIMO, robust digital control laws will be applied in the development of a

combined FSS/RMLA control scheme for the AFW wind tunnel model for FY 91

test and evaluation. The development of an integrated structure and control law

design approach based on hierarchal multilevel decomposition and optimization

techniques will be applied to vibration problems associated with large space

structures. In addition, activities to develop aerodynamic sensitivity information,

initially using a finite difference approach and then based on analytical

expressions, will be developed for the hierarchial aircraft design approach.

Investigations will continue in evaluating the feasibility of employing "smart

structures" technology for aeroelastic and ASE application through more

detailed analyses and simple wind-tunnel demonstrations. In the Applications

and Validations area, the cooperative effort between LaRC and Rockwell

International will continue with the design of multipoint and multifunction digital

control laws for evaluation during the second series of wind tunnel tests.

Activities have also been initiated to provide preliminary aeroelastic and ASE

evaluations for the generic supersonic transport configuration associated with

the LaRC High-Speed Aircraft Multidisciplinary Research Program. This effort

will also involve the application of integrated hierarchal design procedures, the

use of ASE active control design algorithms, and wind-tunnel test demonstrations using semispan, actively controlled, aeroelastic models of the flight vehicle.

Selected highlights of ongoing FY 1990 research are shown in figures 77

through 84.

Analysis and Modeling:

- Maximized Gust Load Computations for Nonlinear Systems

- Modelling of Nonlinear Aerodynamics Using the Volterra-Wiener Theory

- Investigate Time-Domain Aerodynamic Approximation Methods for

Aeroservoelastic Analysis

Control Law Synthesis:

Evaluate Smart Structures Technology for Application to Aeroelasticity

LaRC High-Speed Airframe Integration Research

Develop Unsteady Aerodynamic Force Sensitivity Analysis Capability

Applications and Validations:

Multifunction Digital Active Control Law Design and Validation

Apply Integrated Multidisciplinary Design Methods to CSI Problems

Landing and Impact Dynamics Branch

Figure 85 lists the areas of continuing activity in the landing dynamics

side of the branch for FY 1990. The activities include continuation of the

development of the tire modeling strategies through in-house efforts, a contract

study, and several university grants. Work will continue to develop a data base

on the operational behavior characteristics of radial and H-type aircraft tires.

Efforts will also be focused on research with the active control landing gear for

the F-106B aircraft with the goal of demonstrating the potential of the active

3O
control gear during landing and ground operations. The ALDF part of the

Runway Traction Program, which began in FY 89, will continue in FY 1990 as

well as the continued support for the Heavy Rains Simulation tests using the

ALDF with a test wing mounted on the carriage. These experimental and

analytical programs will develop the landing gear technology necessary for safe

ground handling operations of tomorrow's aircraft.

Figure 86 lists the areas of continuing activity in the impact dynamics

group of the branch for FY 1990. Various static and dynamic tests will be

conducted on concepts of composite frames, subfloors, and energy absorbing

components for potential application in composite aircraft structures. Tests and

analysis will be completed of scale model studies with composite beams under

impact loads which will compliment the static data already completed. Efforts

will continue to update the element library in the DYCAST computer code for

enhancing the composite structures analysis capability under crash loads.

Various analyses of composite structures will be carried out on the branch's

MicroVAX computer and the LaRC CRAY super computer complex utilizing such

codes as NIKE2D, DYNA3D, PAM KRASH, and MSC/DYNA as well as

DYCAST. This analysis effort will be coupled with the experimental program to

provide a fundamental understanding of the physics associated with the

response characteristics of composite structures subjected to crash loads.

Finally, initial tests utilizing the composite aircraft fuselage components should

be underway in FY 1990.

S.oacecraft Dynamics Branch

During FY 1990, two major areas of research will be emphasized (figure

87). The first is the control of flexible spacecraft under the Controls Structures

Interaction (CSI) Program. Focusing on ground test methods, system-level

experimental studies will begin on a large model which evolves in complexity

with time, the CSI Evolutionary Model. These experiments will emphasize

dynamic characterization of the basic structure and control studies using a 15-

thruster pneumatic-jet control system. A second structure, the 20-meter-long

Mini-Mast will continue to serve as a focus for evaluating flexible spacecraft

control algorithms developed by guest investigators from three universities.

The second major area of research, structural dynamics analysis and test

methods, will emphasize system identification and test methods for space

structures which cannot be accurately tested for dynamic behavior in Earth

gravity. Because of its large size and expected flight schedule, the Space

Station Freedom will be used as a focus spacecraft in the expectation that

methods developed can ultimately be verified using on-orbit data. Tests of a

1/10th-size, 1/5th-frequency, hybrid-scale model of an early SSF build

configuration will begin and requirements for practical on-orbit tests and data

acquisition on SSF will be developed. Advanced configurations of SSF for

Human Exploration missions will be studied to assess the importance of

dynamic behavior on design and control. The important problem of predicting

31
and controlling the behavior of multiple flexible bodies undergoing large

maneuvers will continue to be studied and a workshop will be conducted on the

use of the LATDYN computer program for analysis of such problems. System

identification will continue to be a research area with experimental evaluation of

algorithms which learn in repeated tests being emphasized.

CONCLUDING REMARKS

This publication documents the FY 1989 accomplishments, research and

technology highlights, and FY 1990 plans for the Structural Dynamics Division.

32
33
LU

I--

Z

LU

"1-

0

rr'

LU

LU

rr'

ILl

--I

0

Z

--I

_l__.,._.____._ _ IN-IrENTIONAELT_"

34

PRECED1NCi PAGE BLANK NOT FILMED
<

_zZ z

[- <

B

z_ _

35
r_ r_

uJ ,,l

.J .J v v

r_

UJ

.Jv

r_

UJ

r_

UJ

.J

Z0m

O0ii

r_

00oZ

>- a

..J

E:

:3

I--- 0

:3

IZ:

I--

I-.-

(/)

rl"

"r"

I---

i11 Z

<1:

OCZ0

_.1

O' m

I--

=3Z0

rr

uJ

CO0JZ

>-

lu. '_

._ >- On" ___.

I-- '_

n- _.1_

0WZ

Zm ,_

U. 0m

u.! >. 0Z --J

rr (0 0

U..J

rr uJ

,,'0

O. rr

"I-

>-

pro0

Fu.

rr uJ o 0

rr n- O '" 0

rr.

uJ

n0m 0 Z

>-

rr"

I"-

r_ .._ 0 CC n I-- 0

111 rl" O I'-"

-..i

I.I.

36
°i

.,'37

ORIGINAL PAGe'

BLACK AND WHITE PHOTOGRAPH
38 ORIGINAL PAGE

BLACK AND WHITE PHOTOGRAPH
_<= =z S_ _ z_ _ _=oo z<

_= _ _ < _- o=_

m_£ <_m_ _wz _ OUm

_E

-- ZOW

Em _<o m

_o _<_

03

,,.-,=_ == = S .,=, o ._==,.

_

0

< (.3 uJ

13.. ,K I- '<

_, < <

,.6

°_

39
4O
.... [...... Illlllllllll

C_

©

v

Im

01

41

ORIGINAL PAGE

BLACK AND WHITE PHOTOGRAPH
U.

42
L

LO

c

× -aS

0

_, >., C,Q-

_8 "0 _0 CO

-- o _-E}

_j b __' __ Ek3o

(J __ o _ -.£ -co°

@ t • I @

-__ , , ,,

i i ii

r,j

o

ill

!14

II

:{

L

L

,l

IL

.. _x_

,, , . i ilrnr ] --

,.o

u.

43 ORIGINAL PAGE

BLACK AND WHITE PHOTOGRAPH
44
_J

E"'

p5--.

::3

45

ORIGINAL PAGE

BLACK AN[) Vv'_"i_ , "
46
ORIGII",i,AL PAGE

BLACK AND WHITE PHOTOGRAPH

0

<

/

/

/

0

O_

I:I:1I....

,.,.,_

!.1,.

0

0

d

C

lf3-C

"0

0

1,1.

"7

c_

47
48
I--

I::I

I--

Z

0

\

ORIGINAl.: PAGE

BLACK AND WHITE PHOTOGRAPH

d

09

UJ

i

O

Z

LIJ

::)

O

W

£1:

E_ .....

i)

..... _

N k__l_.__,'.LJ i _ l ........... I t........

_ o o o o o o

O-N

LL

A

I.I.

49
5O
I-,.,

(b

E

..,-L

,.Q

v

('M

ii

51

i

ORIGINAL PAGE

BLACK AND WHITE PHOTOGRAPN

r  ̧ _

t_

I

Eo_

e,-

E

x

O _

°

t °

E

O

llrlr" ]]]- 11111rn_ ........

i

A

.0

v

c')

L--

I.I.

53

ORIGINAL PAGE

BLACK AND WRITE P,.--_-"""',_D_
A

m

Im

,i

54
55
LIJ

:I:

I-- 0

I-0

I,I=I

U=

I.I=

f-

.o

.o_

.O

O- <

o9<ZEO

vp.

.=_

-{DE

(DEDOO

"O

(D

JQ

>,

1D

o9

.EO

o9

(n

(D

(D

(--

)-

m

in

,p,

(1)

IL

56
I I I I •

0

0

|

A

I.t')

im

I,.1,.

57

ORIGINAL PAGE

AND WHITE PHOTOGRAPH
0

58
iiii_iiiiiiiiiiiiiiiiiiiiiiiiiiii!

iiiiii!iiiii

ii!i_iiii_iiii!iiiiii_iiii_ii!ii_ii_i!_ii_iiii!iiii!i_i!ii_iiiiiiiiii_i_ii!i_ii_i_ii_ii_ii_ii_

iiiiiiii:ii_ii!iiii!ii!ii!iiiii!ii iiZ_ii:ii'ii  ̧_i_i:i_ii:ii:::iiiiiiiiii

iiiiii_iii_ii_iiiiii_ii_i_iii!i_i!_i_ii_ii_iiiii_ii_iiiiii_iii_i_iiii_iiiiiiiiiiiiiiii_iiiiiiiii_iiiiiiiiii!ii_iJi_ii_iiiiiiiii_iii_iiiii!i!i

iii!iiiiii_ii!i_ii!iiiiii!iiii_i_iii_!iii_i!iiii!iii_i!iii_i!ii_iiiiiiiiii_iiiiiiiiii_i_iiii_iii_i!iiiii!iiiii!!iiii!iii_i_iiii!iiiii_iiiiiii

ii!iii_iiii:ii_iiii_ii_ii_iiiii_iiiiii_iiiii_iiiiii!ii!_ii_iii_iiii_i!iii_iiii_i!i_i_ii_i_ii!_i

i!iii!iiii!ii i!iiiiiiiiiiiiiii iiiii iiii! iii

_!i_i_i!i_i_i_i_%_!i_iiii_i_i_iii_i_!ii_i_!_i_i_!_ii_i_i_i_iii_i_i!ii_iiii_iiii_i_iii_i_iii!ii_i!iiiiiiiiiii_!ii_i_i

i_iiiiiiii_iiiii_iii_i_ii_iiiiiiiiiii!iiiiiiiiiiiiiiiii_iiii!iiii!!_iii_iiiii_iiiii_ii_iiiiiii

_,___!ii_,,!!,_!_i  ̧,

iiiiiiiiiiiiiiiiiiiilili_ii if:i!ii:iiii_i! ililiiiililii_iii

i_ii_ii''i'i'_'i'_i'i'_'ii _'i''i?_'i'ii'i?i'i''ii''

'iii'i!!_,ii'?i'!'_i,!ii_"_i','iii_ii'_i_'iy:_i ',

w:_::: __:y_<::__: ::-_

59

ORIGINAL PAGE
D"

T"

,m

1.6

6O
ORIG!r_.AL PAGE

BLACK AND W_¢',[= P'-_OTOP_RAPH

,-.I

Z

61
62
ORIGINAL PAGE'

BLACK AND WHITE PHOTOGRAPH

i

Z

e_

63
," _,...,%

!

J

- i

i i

i

I

64
T--

ii

65
0

0_

14.

66
c_ Eo

LLI_

..J <1:• o_ +_ 03

LLIcl)_ _o 0 E'_

WZ0 =_-

--"0 ,-,_-

"-" "r- o"

--" Li._ CLD .._"

(D

'::C--

I.,L.!_ m I,.n.I

uJO

nnn 0..

!-.0 (-. Z !,,,-.

O_

-- ILl e-" C,g)i_., o

nun ,..,j

nnn .__

nun m_E a 00

e-

"00

F-- e_

|]IIIIIII

ooo

iiiii!I!!

oo

.s--

IIIIIIIII

C)

1,--

II!11IIII

67

oooo

_E

oo

_)

o

at-
68
ORIGINAL PAGE

BLACK AND WHITE PHOTOGRAPH

A

,,Q

v

,,1=.,

&...

oI

IL

69
7O
71
0,1

l._

01

ou

i.1,.

72 ORIGINAL PAGE

BLACK AND WHITE PHOTOGRAPH
n- _ z

>

i

> ................. ,

lk x%%%x%%%%%%_% _%% ' ' . _

i %%%%%%_ %%%% %%% ' ' k . 15i III tl_t

.,%_ ,, _., 1_'1_ ,.. _, _. ]_ , _ ' _ , _ _ _ _ _'_ ! '_.

",",".' ,It)," _" ',! ", i'.' ;, ", ,v_ 00.:, . "10 .' e..'. ,, _. ,.....,, m ,--!_ _' ,Z' , o_ .,,.,,.,.,. ,-,-,.,,

,..,, , O, .. "._.. ,,''= " m , ._..- m ' .._, _ , .,

.u', ,,..i- N ,. "i,Ll. o., _ ' c, o'_ >, ' :_. ,,,. , ,.

<_ '_.', ...."_ , c, ,,.. "' ",............. '-.-" ,0 _ • _,........ ....... _,..,: _ . ,., :, lO" • "-_ ":

._.:i• ' • _ ,.,n-. , _ ,,,,,,,,,-,,,,,-,,,,,,

U.l ,., ._-_,, ,..,z,-,,,,,,_ ,,-,,,,,,,,,,,,,,,,,,, ,J: , _ :,

•_-,:: :,',:," ,, :: ,,,,,,............

,_ ..... !,,_',',,:," ,','",'",'",'"'"" "'"','""

........... ._....::...

I.- p

Z I--

"' z

uJ

-r n

_- >" 0 --

rr rr .j

0 0 ,,,

,_ uJ

-r _u x

4

i--

73

<=

Z asuodsa_J _suodsa_l asuodsa_l

uu<

uJIm

u.a

Z--'

w<

U,,I U')

9

I,,g

II

Z

u

LL

C"N

II II

N

\ x

_cO

-

-

°

°

°

°

°

°

- O

0

G,)

a--

C

i

m

e.-

o

o_

q,)

E

ee.-

0

0

>

,.-k

.Q

v

C_l

C_

°_

LI.

75
76
77
78
LI.I

o

II0

C:

8"_

0

,-r>_

W -"

n-w ._

0

e=

••

\

7g

vJJJJf

I%

U)

_o

_a00m

if)

L. m0

e_

o_

° i"

a w _- __

I'_ ii

g

_ o _±_

z.. ._ ._ _lO _ .- _.. c

_a z m.__

,,IZ

\ ,(

\ \.

O0 _ 0

Q •

t:l.

I

_¢ O0 C4

I

0

0

E

e-

_CO

0

O_

I

x

_ I_ o

O

O

--O

cO

--

c)

(I)

--

" O

CO

I

cO

(D

_- X

A

i--

81
v

O_

ll

U.

82
i

Q)

m

0 _ "-

L_

13.

LI,I _J) 0

1,1,1.-I _ I cn

•I-o _

._o _ •

,'5,,_ _._-_

.__g_

-

I--

o

0

X _._

w E_

©_o

._ o_

o_m -_ ,0 o

_0 _

Q) ,-_ N

OF'I'

!

O

H

i

D

I

k w

62 CO _ 0 C_ CO _ 0 C_ CO _ 0

0

tO

0

0

×

( [] [] []

( 0 0 0

( [] 0 []

(

+

O

O

O

O

0 D D [] (

0 0 0 0 (

0 [] 0 [] (

[]

o..._

OD-"

°_

A

(N

8S
_uJ

(/)

=g

--I- 0

_

I_lO

_.U- 0

...l O0

UJ I"

_.,J

U,I=)

U.I

0

O0

OU-0 0

O.

0,)

(1)'I:3

z_0

0

0'I

l,l,.

84
o o

B5
86
8_
uJZ0m

-IF-

-r

p.0Zm

p-

..I

uJ0

rL

.I

U_

>-

..I 0

"r0

U_J

U)

>.Z

rr

,ii

F"

..I

IL

"0

C',,I

CO

Q)

I..,

.1

I,i.

88
[]

0

[]

°80

00

BS_

I I

Oo

o_%

0

0

O0

0

0

8

0

0

0

{}

t_

ii

C_

89
__f

9O
91
CO

s._

:3

U.

g2
93
94
a

i,1Ni

iI

:3

II

a

iI

u. c_

II

0

..!0Z0

(/) Z

I:1:

F- a

n: ZO

iI

.=_ a

O.

O. i

iIO

95

ORIGINAL PAGE

BI. ^CK AI"ID _,'JITE PHOTOGRAPH

Ni II

tt}

II

+1

II

0

II

AV

IQ

t_

ii1

UI
O9

]

m

0

0

0

ORIGINAL PAGE

BLACK AND WHITE PHOTOGRAPH

96
I

>-

i _L 0I

Wm

LL'

e3 (-9

o'_o

_ oZwo

I-o

r_

__ i_o

1-- -- £r I

_Ow

w _zi z

_.1

o

O

on- _ ,_ _rr

ow ' _

!i _oi11 .._1 l o ',

I.-_ _z

--0

_z

OC/_ >-0

_E_ zw

z_

__o

14,11,=,

e,, I.U

.,-I w

I-

_o

rr

I-- 0

I.Ll

,_] W0W

D_

rr-

: I-- 0

r_"

03

l--

n" <

03

ii z

I-

__7w

>

0

03

7-

o30

o3z

i1

co

ti n.- i uJT

p- O

,

Z

-JzZ

1--

121 ZZOiOI

-1

a=

a=

b:

14=

97
c1.1

98
e_

V

U.

99
IO0
ORIGINAL pAGE

BLACK AND wHITE pHOTOGRAPH

101

ORIGINAL PAGE

...... '-,- PHOTOGRAPH

,,,.L

,,Q

=l
102
O_-O g

= oc,- cl "_

,_ ._J°, .,..,,

,,,_ CL) _c-- "-_1 o, (_1 -_

i'_ q) >',C ,-i

¢/)-_ 0 e- I

e -:7_i;!ii_5_-i_iii:i_iiii:_!ili_-i!i:!;iiii!; o.... I N

"-_ ":::$: ._.>.'..:!:._ $_:i:_:_

":::..'.':.'.. _:j_:_:!:!:!:!:

.Ir.) < :::i::::i ::i]i::!_#iii!iiiii " _ Z

-o %ii_iiiiiWi:::: _ -_ E:

_,,,, _ _ :_"':"' -_ oo_

LLF

LU'_

(/)LU "_

o -r (_

I:E ._1

=>0

Iv"

O

70"-_ (n____

--r-_ _:

.o

O

!._

:3

o_

ii

103
A

V

0

O)

,m

1,1=

104
0

105
E

13. 0

I,.,...

c- o0oo

cV

i--

106
_m

.1

U=

107
108
=0

c

O3

°_

co

G)

==J

CO

_c_

o_

_A_

co

:_ _== =).=a

0 o _

c- ==_"'- (I)

_ "_E

0

"sO 0 .O-

_c °_ 0 i_

o

L_ "0 0

_'_ c.-

Eo __

oo c-'5

0 -E0

CL c_ c) cO

L==c- =_ _==c=''_

_0_ t_O _

=&==a "-- "-- O. _c= 0

0"_0 c- CD _

_ z=8

0 0 0 0 0

0

c

0

0

m

.m

c_

°_

121

A

s-_

11

109
,.-k

v

(I)

14=

110
>.

¢)

,.,'8

111
112
a

! I I I [

1 I I I YI I I I I

I I I I

! I I

113

ORIGINAl PAGE

BLACK AND WHITE PHOTOGRAPH
114
.-4.

v

CO

¢33

I,.I.

1  ̧ ,

.... 115

ORIGINAL PAGE

BLACK AND WHITE PHOTOGRAPH
ORIGINAL. PAGE

1 1 6 BLACK AND WHITE PHOTOGRAPH
7<1

>- mCZCZDZ

,_] 0

LO

l,Ll Z0a

DC} cO w

13__ ILl

_-- C_

n- O

___<

I"-'ILWm

iI Wz I w_ I _ I <o IIIII1

Z_-- --_--

0

Zo I w

--0

z I o I z I < I < 1 z IIIIIIIIII1 Z I ZO<w I o I

<z

>-n

-r

CO

oZ0 I

,,,_ I 0 IIIIIII

_u I

_n I z

-0 I

0__0 I

0: II

,,, I z co I 0 -_ o _-

-o-_-V-

_.1<

_t

oI

o ,,,I

a_ ___I

o FI

C3 z

I

<I

_ _..1 <

I

"'I

_..1

rr

LU O0

-50

z_z<

Zoo

1I

<w

<<

o_oI

Z0

z

V0

u_zo

z<__ I o n- Lu I "' > t a II

__z I

i_ I

O, I

"' I < I 0

co I Z< t

,,, _" I

v, rF

0z LU

r_ I

_nz I © o I

____ I

ozc

>- u_y Z Lw

LW b- > o0 I_ < IIII!1 o

cOZ n_ I -rl I °1

co

F-

__ 00WW©

__. iii

r_ oO 0 _ D

13_, LU I.IG. m iii

:=) 'I-- -- 0 _ o o rr ZI

>- 7<<

oz -_! Z © w

UA

Or.l] bp--

LL

I1

u']

C'4 ><

117
V

(D

"!

IJ.

118
ORIGrNAL PAGE

BLACK A[_D _'Ji'_ilE PHOTOGRAPH

119
120
ORIGINAL PAGE

BLACK AND WHITE PHOTOGRAPH

NI

......... _:_ _i

_J::i

ii:

ii

sL,,_:

_:::.?)- ?_

=

:t

121
122
123
124
Z

_ZZ

Z_

0_

_Z

.1

[..,m

=0

0

t)<

u-

{9

;Zm<

t)

U_

cOo

o_ _-

_- u_ o +I

,-1

m c_

¢..

c- c"

[]+

It)

c_

U.

125
126

in

,o,)

:D

LI..
r_

127
v

U_

0

u.

128
EXPERIMEN

OF

_[AL SE -rL.IP

COMPOSITE

FOR V!BRA [IONZ:L:I!:

FRAMES

i

129

ORIGINAL PAGE

BLACK AND WHITE PHOTOGRAPH
SENSITIVITY OF FRAME RESPONSE TO MATERIAL PROPERTIES

0,5

DEVAUFREQ

0.4

0.3

0.2

0.1

0.0

1.0

I

;I

MODES

ENERGY CHARACTERIZATION OF MODES

I el

::::i:i:::::::

:::::::::::::: e 2

r_l glt

o

It)

I,,,

:3

,m

I,i.

ENERGY

RATIO

0.8

0.6

0.4

0.2

0.0

I

?:iII l---I m u_u2_u_u

'7. '3 b, _ _o 1 '_ o_ ,_ ,¢, _9_ _,'3,_, ,_ _,_ \q ,_'_ ,_ ,-_ :_i_i_i U 3 /U

MODES

130


-- co

o

%

l

I

!

z

0

0

W

_.J

LL

W

,.Q

Lf)

(1)

o_

U.

133
v

tO

ID

0

U.

134
ORIGINAL PAGE

BLACK AND WHITE PHOTOGRAPH

135

ORIGINAL PAGE"--'

BI._CR' AND v,.,'L_!--_- -
136
137
138
W

I=

III

I..,

iCO)

W

_f

,ffl

r_

co

L_

,m

LI.

139

ORIGINAL PAGE

B_ AND WHITE PHOTOGRAPt4
w"

(__z iO0 ,< "0

__>-

1.1.1J

!--_o

0 O°

0

rt"

,_ aJ0 0 _._ Z O_

00_ 00_

-- LI.I LLI I

_wo\

LI.. I_" ,-

I_-x

Zl--,,,

._.._o

Z _" ,,,o

._d ,,-o _"

-0

r_u_

-5_ ,,,\

i --1

i_._ u_

_U. ,,, 121

wod \, I-- .<0

--I co

,_o

_"x

_ ! I I 0 0 0 Z -_- co a_

=EJ

U.I

rt- n-,< w

0 I

o_1 \

\

I0

00

CO

0_0E00

n0

WZ --

,_o

rro 0

o

LL "-

I-- _-0

•

O_ 0 nI- w w

o _= I W

rt"

h- WW IJJ --

rn n" t--

--W

-- >. c_ ._

_

000

II

I

0

I

III

L_0 Lr)

W

::L

0

CO

E_

uJ

L_ _j Z<< 0

A0

,I

140
oi

I,i.

ORIGINAl_ PAGE"

BLACK AND WHITE PHOTOGRAPh'

142

PREC'EDIr_G PAGE BLANK NOT FILMF_.,D
141
0

tOw

C_

_00_

--w

0

_iU_U<

_-_ _0 Z __

_J0

Y-_

o

yLLI

U')wO

O__

rr i-_U

Z_ rr

orr ',l

UF__--

_0Z

0

rrZ0UZ

O_0U

,_I

r_

t--

_J

y-

_! 0

rrZ0UZ0

F-0

rr<

>-0

rn

reX

ILl

.J

L_

_ZW

r_0W>W

r_Z

>-

r_<

nw

>-

rr

_z

_Jzoz

z_<ZZ

r_<

w

_,_ rr

u_< u'_

_J

I-- I --

_._1 0

rrZ

_--0

Z i-- 0 _--

--<

U

_r

-- l--

_r)U

>- >-<

<o rr

z -_<

<0T

Z U,

z -r __! o u <

I-- "' r_

F- -J F-

_r; L_U

W0 rr

U _- __

<, or;

r_ ILl _

Z

< io

>- iU --

r_ _0 I-- < < Z U __ o

I--< "' Z O

0 _-_ (_-

ILl

<_0

i1

143
A

mv

t,O

,m

14.

144
i!i!iiiiiiiii_iiil  ̧

145

ORIGINAL PAGE

BLACK AND WHITE PHOTOGRAPH
£0

0

LL.

146
_o

I--

>.

.J

Z

= ° I

m a

0 0 0 0 0 0 0 0 0 0 0 'e--

(ZH) AON3NO3Hd

0

W

f INI -=_

..IE

_w

..................... I_1 n-=E

, .-- _

0

i-i

0

i

u.l

.I1

V

O4

.m

U.

147
148
G) '-

°° i

I _ _!lt // c._ I

_=

- I_ // _:_ _

=J

.-=

IIII

E

149
::)

Cl:

I,-

_m

0

150
d

0

0

f-

"1-111

a.o

,.J,_

0 o

W

_m

No

_0

W_

mZ

m 0

I--

a

z

0

U_

O4 _0 0

d

(LUql) Uo!idLUnSUOO SeE)

04

00

I | I I I I | I I I I

0

0

0

(u!) Z

0

o

0

i i1 0

oV

£0

!

%-

>-

G)

0

0

0

| i | I II I | I | i i | | i |* i 0

o o_

!

(u!) z

r-

>-

V

_D

*l

151
.-4,

b5

U)

tm

14.

152
LIJ

!-" m

UJ

E/

IZm I-Zi

0

IcCJ u

"I" Z0i

I-NmI

la. 0 I c

c

"O7o

.c_.c_

E.--o_

o_

Zl-- I

'/

Sf

/}

_'I3Z o

0

("d

m

dcc

I

o

\,

_ Z3

_E

._._-__

..00

/V

r- cu g _ • •

IJ

(,D

liB

.i

I.t.

153
154
m

W

>_

WW

Ch ,..j

O...a

r_

D:dS/D_(I 'AII._Oq3A lOOU

0 !

[ ....

o_ oD_U 'NOIJLISO,I _ .1.0011 _

3

0

I

j h

S.Z'IOA '"IVNDIS DNINklVL'I1

:.'1A l_lCd _1(110 I,'_

C_

[-

¢.q

v

., _ [-

" ,.o,,N_,._,v,_oo, _.

_ _.

;fl

_ _ z z,_

Z _ _

_e ,.I[,..

_ . . ,

155
v

I',.

QP

Q)

,m

14.

156
i .......................... i

u.. 8

LU .

9_

g

8..it "

I11 m

g_

l-

_'P v'u'l,l,l,n _ C'

(NIl IN'_I_I'_OY"IclSI(]

157
158
.o '1=

0o

I

I

o

o

o

•Sep 'u0!le!AeCIMeA

LO

d

I..0*

0

i

Ob

Q)

13

d

o

o .=__

d >

d3

tO

13..

,i

I.I.

159
160
Ill

I

G)I

D.I

OI

"01

CI

tll

t/ll

OI

El

tDI

Iii

>',l

Ill

¢1)1

CI

Imi

OI

OI

I1_1

000000

000

000

090C

0

I°

0

0

"T,

0

v

E

0

0

E

F- o

.Q

_0

L--

.B

U.

161
162
PRECEDINGPAGEBLANK NOT FILMED

163
"1"--

ID3

1.1=

164
09

ILl

m

:D

r,.9

m

!,,I.

Z

o

\

i ii i

II! _ eo'__

"r >_=

t-

,.,.._ ,=,_ < e i i

• I • • t I •

..... i I

¢0

1,1,1

Ira

v

'5"

°_

I,,I.

l,U

B

I,IJ

0

Z

<(

rr"

LU

d

_ it

ORIGINAL PAGE'

BLACK AND WHITE PHOTOGRAPT[

165

ORIGINAL PAGE

BLACK ,_Nn .....
v

I',.

Z3_

U.

166

.t
LI.

167
A

¢_

i1

168
\

169

ORIGINAL PAGE

_._L.ACK AND WHITE PHOTOGRAPH
U)0m

=i<

=

zQ

m

.j -_ 0

_-c

o,- E.o

c_

rr _:

cO o

nr0

0

I-10

rr

Am

r_o

i._

:3

,1

U.

170
,,,j

171
>,

"13

u_

LO_

=m

LI.

172
oi

173
r,.

i,,.

Im

O)

U.

174
i

i

A

o

x

A

IN

175

, k Q"
I,,,,,,

,1

I,I.

ORIGINAL PAGE IS

OF POOR QUALITY

176
177
(3)

L_

--!

(3)

=l

14.

178
179
0

(D

:3

U.

180
0

cO

,m

181
..J,

cO

0

,m

I.I.

182
0

rr

ILl ,"

U.i ¢_

,-4.

v

CO

°_

183
m

v

cO

0

U.

184
rr r"-I 0

Q_

'-1

,m

t,M

185
v

CO

186
t'-

C_

187

I

A

el

CO

°_

LL
v

CO

Q)

I.I.

188
• 0

A

11

189
iI

190
(6

I,,.

°_

U.

• • • • • •

191
192
1. Report No.

NASA TH-101683

4. Title and Subtitle

STRUCTURAL DYNAMICS

ACCOMPLISHMENTS FOR

Report Documentation Page

7. Author(s)

Jacqueline G. Smith and

James E. Gardner

9. Performing Organization Name and Address

Langley Research Center

Hampton, Virginia 23665-5225

12, Sponsoring Agency Name and Address

National Aeronautics and Space

Washington, DC 20546-0001

2. Government Accession No, 3, Recipient's Catalog No.

5 l Report Date

January 1990

6. Performing Organization Code

8. Performing Organization Report No.

10. Work Unit No.

505-63-21-02

11. Contract or Grant No.

13. Type of Report and Period Covered

Technical Memorandum

DIVISION RESEARCH AND TECHNOLOGY

FY 1989 AND PLANS FOR FY 1990

Administration

14. Sponsoring ._gency Code

15, Supplementary Notes

16. Abstract

The purpose of this paper is to present the Structural Dynamics Division's

research accomplishments for FY 1989 and research plans for FY 1990. The

work under each Branch (technical area) is described in terms of highlights

of accomplishments during the past year and highlights of plans for the

current year as they relate to five year plans for each technical area. This

information will be useful in program coordination with other government

oraanizations and industry in areas of mutual interest.

17. Key Words (Suggested by Author(s))

Accomplishments, research plans,

aeroelasticity, dynamics

18. Distribution Statement

Unclassified - Unlimited

Subject Category - 02

19. Security Classif. (of this report)

Unclassified

20. Security Classif. (of this page)

Unclassified

21. No. of pages

193

22. Price

A09

NASA FORM 1626 OCT 86 For sale by the Nationa] Technical Information Service, Springfield, Virginia 22161-2171

NASA-Langley, 1990