| Enabling Technologies for Nano Air Vehicles |
10-Feb-2009 |
86 pages |
| Authors:
Jamey D Jacob; OKLAHOMA STATE UNIV STILLWATER
|
 | This project investigated several areas with the aim of improving performance and operational use of nano air vehicles (NAVs) by understanding fundamental operating principles and developing key technologies. The project developed plasma actuators for thrust and maneuvering control and examined flapping flight through the development of a high speed videogrammetry system and a gust/shear tunnel to replicate flow fields seen as the NAY scale. In the first portion of the ... |
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| Ship Airwake Correlation Analysis for the San Antonio Class Transport Dock Vessel |
21 MAY 2008 |
16 pages |
| Authors:
Jason Geder; Ravi Ramamurti; William C. Sandberg; NAVAL RESEARCH LAB WASHINGTON DC
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| A space-time correlation function method is applied to the analysis of Large Eddy Simulation (LES) unsteady ship airwake data computed for the LPD 17. Correlation functions are computed for potentially dangerous velocity bursting events visually tracked in space and time in the air vehicle landing zone. It is shown that a correlation function approach is of potential value but the usefulness of the approach is very sensitive to the knowledge, ... |
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| Modeling of Flow about Pitching and Plunging Airfoil Using High-Order Schemes |
13 MAR 2008 |
39 pages |
| Authors:
A. Povitsky; H. Gopalan; AKRON UNIV OH
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| A high-order non-uniform compact finite-difference algorithm with numerical filtering and low storage Runga-Kutta scheme is developed to perform numerical simulations on orthogonal grids generated about plunging and pitching airfoils. The grids, which move with the pitching and plunging airfoil, are generated using "Streamfunction as a coordinate approach" (SFC). SFC is widely used in combination with lower-order schemes in Computational Fluid Dynamics. The straightforward implementation of SFC create rather coarse grid ... |
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| Environmental Support to Amphibious Craft, Patrol Boats, and Coastal Ships: An Annotated Bibliography |
05 MAR 2008 |
48 pages |
| Authors:
Charles M. Bachmann; Robert A. Fusina; C. R. Nichols; Jack McDermid; NAVAL RESEARCH LAB WASHINGTON DC
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| This annotated bibliography is a selection of citations to books, articles, documents, and data bases highlighting environmental conditions that impact the safety and performance of amphibious craft, patrol boats, and ships designed for coastal operations. Each citation is followed by a brief summary and evaluation of the source (i.e., the annotation). Most annotations will define the scope of the source, list significant cross references, and identify the relevant environmental conditions. ... |
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| Unsteady Aerodynamic Models for Flight Control of Agile Micro Air Vehicles |
2008 |
5 pages |
| Authors:
Clancy Rowley; PRINCETON UNIV NJ
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| Objective: Obtain models for unsteady aerodynamics of fixed-wing MAVs (e.g. incorporating dynamic stall, vortex shedding). Technical approach: Systematic models using approximate balanced truncation (balanced POD); empirical, phenomenological models that capture correct bifurcation behavior. |
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| The Flight Control System of the Hovereye (Trademark) VTOL UAV |
MAY 2007 |
17 pages |
| Authors:
Paolo Binetti; Daniel Trouchet; Lorenzo Pollini; Mario Innocenti; Tarek Hamel; Florent Le Bras; BERTIN TECHNOLOGIES MONTIGNY-LE-BRETONNEUX (FRANCE) UAV SYSTEMS
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| This overview paper covers the flight control system of Bertin Technologies Hovereye(registered name) mini vertical takeoff and landing (VTOL) UAV, including development, verification in simulation and flight test results. Hovereye is a demonstrator of a short range reconnaissance platform in support of army units engaged in urban combat, such as in peace-keeping missions, with an electro-optic day or night camera payload.. This system stabilizes the vehicle, provides operators with easy ... |
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| Evaluation of Convective Wind Forecasting Methods During High Wind Events |
MAR 2006 |
80 pages |
| Authors:
Christopher J. Kuhlman; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
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| This study investigates convective wind gust forecasting methods for reported gusts in the Midwest, Central, and Northeast United States from June and July 2005. Three methods are examined using MM5 model data; the T1 and T2 methods and the WINDEX method. The model-derived wind gusts determined by each method are then compared to wind reports from the Storm Prediction Center's severe storm reports archive and reports from observing stations. Model-derived ... |
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| Research and Development of a Scaled Joined-Wing Flight Vehicle |
APR 2005 |
25 pages |
| Authors:
Afzal Suleman; INSTITUTO SUPERIOR TECNICO LISBON (PORTUGAL) DEPT OF MECHANICAL ENGINEERING
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| This report results from a contract tasking Instituto Superior Tecnico as follows: The Grantee will investigate the aeroelastic performance of the joined-wing concept. Dr. Suleman and his research team have proposed to investigate the aeroelastic performance of the joined-wing concept by analyzing, designing, manufacturing, and wind tunnel testing aeroelastically scaled models. The first step will include designing a test assembly to conduct aeroelastic flutter and gust response tests. A fairly ... |
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| Ice Storms in the St. Lawrence Valley Region |
JAN 2003 |
129 pages |
| Authors:
Kathleen F. Jones; ENGINEER RESEARCH AND DEVELOPMENT CENTER HANOVER NH COLD REGIONS RESEARCH AND ENGINEERING LAB
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| The severe ice storm in January 1998 in Quebec, eastern Ontario, northern New York, and New England disrupted the lives of millions of people. The ice that accreted on trees and wires damaged electrical transmission and distribution lines, causing power outages that lasted many weeks in some areas. In this report, ice storms in the St. Lawrence Valley region of Quebec, eastern Ontario, and northern New York and Vermont are ... |
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| An Evaluation of Microburst Prediction Indices for the Kennedy Space Center and Cape Canaveral Air Station (KSC/CCAS) |
MAR 2000 |
111 pages |
| Authors:
Steven N. Dickerson; AIR FORCE INST OF TECH WRIGHT-PATTERSONAFB OH
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| A wet-microburst event on 16 August 1994 at the Kennedy Space Center's Shuttle Landing Facility alerted forecasters from the 45th Weather Squadron (45WS), the provider of weather support to the Kennedy Space Center (KSC) and Cape Canaveral Air Station (CCAS), to the challenges of wet-microburst prediction. Although there was no operational impact, this event caused the 45WS to revise their severe thunderstorm forecasting procedures to specifically ... |
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| Atmospheric Flight Gust Loads Analysis |
JUL 1999 |
49 pages |
| Authors:
M. C. Kim; A. M. Kabe; S. S. Lee; AEROSPACE CORP EL SEGUNDO CA ENGINEERING AND TECHNOLOGY GROUP
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| A new Monte Carlo atmospheric flight gust loads analysis approach is presented. The procedure uses forcing functions that were derived by extracting the turbulent, short-duration, non-persistent components of measured wind profiles. Over 1000 forcing functions were used in each analysis. The results were analyzed statistically to establish the 99.7 percent enclosure, 90 percent confidence level, load values. Results are presented for a medium lift launch ... |
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| Forecasting Downdraft Wind Speeds Associated with Airmass Thunderstorms for Peterson Air Force Base, Colorado, Using the WSR-88D |
MAR 1999 |
139 pages |
| Authors:
Travis A. Steen; AIR FORCE INST OF TECH WRIGHT-PATTERSONAFB OH
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| During the period Jun-Aug 96, four Air Force installations suffered over $4.8 million in damage from convective winds. During the same summer, Air Force Space Command units issued nearly 65% of their weather warnings for convective winds, making the forecasting of convective winds the most frequent challenge to forecasters. This thesis seeks to assist Air Force forecasters at Peterson Air Force Base (PAFB), Colorado, in ... |
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| Development of the Aerodynamic/Aeroservoelastic Modules in Astros Volume4: Aeroservoelasticity Discipline in Astros, Theoretical Manual |
04 FEB 1999 |
80 pages |
| Authors:
M. Karpel; B. Moulin; ZONA TECHNOLOGY INC SCOTTSDALE AZ
|
| This report presents the theoretical formulation of the aeroservoelastic module in ASTROS. Areas covered include the following: generalized matrices, rational aerodynamic approximations, state-space aeroservoelastic equations, flutter analysis, control stability margins and continuous gust response. This report is part of the documentation which describe the complete development of an STTR Phase II effort entitled "Development of the Aerodynamic/Aeroservoelastic Modules in ASTROS". Additional ... |
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| Development of the Aerodynamic/Aeroelastic Modules in Astros. Volume I -Aeroservoelasticity Discipline in Astros User's Manual |
FEB 1999 |
65 pages |
| Authors:
M. Karpel; B. Moulin; ZONA TECHNOLOGY INC SCOTTSDALE AZ
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| The behavior of the structural and control systems of flight vehicles are highly coupled through aeroelastic effects. An aeroservoelastic (ASE) interaction module was developed to facilitate ASE analysis and the application of ASE stability and response constraints within ASTROS. The aeroelastic plant state-space equations are based on minimum-state rational function approximation of the unsteady force coefficient matrices. The control system is defined in a way that ... |
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| Development of the Aerodynamic/Aeroelastic Modules in Astros. Volume III- Aeroservoelasticity Discipline in Astros Application Manual |
FEB 1999 |
45 pages |
| Authors:
M. Karpel; B. Moulin; ZONA TECHNOLOGY INC SCOTTSDALE AZ
|
| The behavior of the structural and control systems of flight vehicles are highly coupled through aeroelastic effects. An aeroservoelastic (ASE) interaction module was developed to facilitate ASE analysis and the application of ASE stability and response constraints within ASTROS. The aeroelastic plant state-space equations are based on minimum-state rational function approximation of the unsteady force coefficient matrices. The control system is defined in a way that ... |
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| Development of the Aerodynamic/Aeroelastic Modules in Astros. Volume II - Aeroservoelasticity Discipline in Astros Programmer's Manual |
FEB 1999 |
44 pages |
| Authors:
M. Karpel; B. Moulin; ZONA TECHNOLOGY INC SCOTTSDALE AZ
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| This report describes the new ASE discipline in ASTROS and the way it was implemented in this project. The MAPOL commands added for the implementation of the ASE discipline are given and explained. A flow chart of the new data templates is given and each one of them is then described separately. This report is part of the documentation which describe the complete development of an STIR ... |
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| Comparisons of Flight to Ground-Based Pilot-Induced Oscillation Evaluation Methods |
MAY 1998 |
203 pages |
| Authors:
Ba T. Nguyen; Thomas J. Cord; David B. Liggett; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH AIR VEHICLES DIRECTORATE
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| This report documents comparisons of flight and ground-based Pilot- Induced Oscillation (PIO) evaluation methods. The study was to develop and modify ground-based simulation methods to improve the likelihood of early PIO detection. The study strickly looked into the linear causes of longitudinal PIOs due to phase lag or high time delays as opposed to nonlinear PIO types such as rate limiting or mode switching. The results of the ground-based simulation ... |
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| Investigation of Strong Surface Winds Associated with an Upper Front Using COAMPS |
SEP 1997 |
90 pages |
| Authors:
Ken Schwingshaki; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
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| On 2 April 1997, strong winds blew through the central coast of California that were accompanied by an intense jet streak and upper front. The event was analyzed with standard synoptic scale DIFAX charts and mesoscale charts for comparison. The mesoscale model used was the Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS) developed by Naval Research Laboratory (NRL), Monterey, California. COAMPS captured features that were not diagnosed ... |
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| Validation and Application of a Transient Aeroelastic Analysis for Shipboard Engage/Disengage Operations |
15 APR 96 |
21 pages |
| Authors:
William P. Geyer Jr.; Edward C. Smith; Jonathan Keller; NAVAL AIR WARFARE CENTER AIRCRAFT DIV PATUXENT RIVER MD
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| A previously developed transient aeroelastic rotor response analysis for shipboard engage/disengage sequences is utilized in the present research. The blade has elastic flap and torsion degrees of freedom and the equations of motion are discretized using the finite element method. The discretized equations of motion are integrated for a specified rotor speed run-up or run- down profile. Blade element theory is used to calculate quasi-steady or unsteady aerodynamic loads in ... |
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| Flight Loads Data for a Boeing 737-400 in Commercial Operation |
APR 96 |
87 pages |
| Authors:
D. Skinn; P. Miedlar; L. Kelly; DAYTON UNIV OH RESEARCH INST
|
| This report presents the flight data collected in 1993 from one Boeing 737-400 during routine commercial operation. The data collection program is part of a joint FAA/NASA effort to develop a flight recorder to obtain statistical loads data on commercial transport (FAR Part 25) aircraft during routine operations. During this prototype data collection program, 593 flights of operational flight loads were collected. Of these, 535 flights representing 817.7 hours, provided ... |
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| Winter Severe Weather: A Case Study of the Intense Squall Line of 6-7 January 1995 in the Carolinas |
96 |
93 pages |
| Authors:
Robert W. Trayers Jr; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH
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| A case study was conducted of the evolution of the 6-7 January 1995 intense squall line in the Carolinas. This event was most intense over central and eastern North Carolina and produced wind damage of over 10 million dollars. A record straight-line wind gust of 64 ms-1 was recorded at Seymour-Johnson AFB in Goldsboro as the squall line passed the station. Numerous tornadoes also were confirmed. This case is worthy ... |
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| Terminal Doppler Weather Radar (TDWR) Operational Test and Evaluation (OT&E) Integration and OT&E Operational Final Report |
DEC 95 |
81 pages |
| Authors:
Radame Martinez; Tai Lee; Peter Guthlein; Steve Viveiros; Donne Wedge; FEDERAL AVIATION ADMINISTRATION WASHINGTON DC OFFICE OF AVIATION SAFETY
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| This document is the Final Report for Operational Test and Evaluation (OT&E) Integration and OT&E Operational testing of the Terminal Doppler Weather Radar (TDWR). It provides a complete account of the results of OT&E testing as well as recommendations for future considerations. This report contains a description of testing and evaluation activities including location, participants, specialized test equipment used during testing, test objectives/ criteria, test descriptions, test results, and methods ... |
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| Integrated Terminal Weather System (ITWS) 1994 Demonstration Phase OT&E Final Report |
NOV 95 |
110 pages |
| Authors:
Thomas M. Weiss; Gloria Yastrop; Glenn Smythe; FEDERAL AVIATION ADMINISTRATION TECHNICAL CENTER ATLANTIC CITY NJ
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| The Integrated Terminal Weather System (ITWS) will produce a fully automated, integrated terminal weather information system to improve safety, efficiency, and capacity of terminal area aviation operations. The ITWS will acquire data from Federal Aviation Administration (FAA) and National Weather Service (NWS) weather sensors as well as aircraft in flight to provide FAA air traffic personnel with products that require no meteorological interpretation. These products include current terminal area weather ... |
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| Aeroelastic Analysis of Transient Blade Dynamics During Shipboard Engage/Disengage Operations |
21 AUG 95 |
25 pages |
| Authors:
William P. Geyer Jr.; Edward C. Smith; NAVAL AIR WARFARE CENTER AIRCRAFT DIV PATUXENT RIVER MD
|
| An analysis tool has been developed to predict transient aeroelastic rotor response during shipboard engage/disengage sequences. The blade is modeled as an elastic beam undergoing deflections in flap bending and torsion. The blade equation of motion is formulated using Hamilton's principle and spatially discretized using the finite element method. The discretized blade equations of motion are integrated for a specified rotor speed run-up or run-down profile. Blade element theory is ... |
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| Integrated Terminal Weather System (ITWS) Demonstration and Validation Operational Test and Evaluation |
13 APR 95 |
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| Authors:
Diana L. Klingle-Wilson; MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB
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 | During summer 1994, MIT Lincoln Laboratory conducted the Operational Test and Evaluation Demonstration and Validation (Dem Val) of the Federal Aviation Administration's Integrated Terminal Weather System (lTWS). The purpose of the demonstration was to obtain user feedback on products and to prove that the ITWS products and concept were sufficiently mature to proceed with procurement. Dem Val was conducted at the Memphis international Airport from 23 May through 22 July ... |
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| The ATC Operational Evaluation of the Prototype Integrated Terminal Weather System (ITWS) at Dallas/Fort Worth and Orlando Airports (May-September 1993) |
MAR 95 |
119 pages |
| Authors:
Thomas M. Weiss; FEDERAL AVIATION ADMINISTRATION TECHNICAL CENTER ATLANTIC CITY NJ
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| The Integrated Terminal Weather System (ITWS) was developed by Massachusetts Institute of Technology/Lincoln Laboratory (MITILL). The ITWS processor acquires data from Federal Aviation Administration (FAA) and National Weather Service (NWS) weather sensors in the terminal area and provides an integrated set of safety and planning weather products to air traffic personnel. An operational evaluation of the ITWS functional prototype was performed from May through September, 1993 at Dallas/Fort Worth (DFW) ... |
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| Flight in an Adverse Environment (Le Vol en Environment Hostile) |
NOV 94 |
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| Authors:
ADVISORY GROUP FOR AEROSPACE RESEARCH AND DEVELOPMENT NEUILLY-SUR-SEINE (FRAN CE)
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| The environment in which an airplane must operate is a major cause of aircraft accidents. This lecture series focuses on specific aspects of the environment, both natural and man-made, which are the major contributors to these accidents. These are as follows: Wake turbulence and the generation of trailing vortex systems; The results of an extensive flight test program concerning winter storms off the east coast of Canada including effect on ... |
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| TDWR Scan Strategy Implementation |
02 SEP 94 |
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| Authors:
Daniel P. Hynek; MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB
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| The Terminal Doppler Weather Radars (TDWRs) installed at major airports around the country are intended to enhance the safety of air travel by the detection and timely warning of hazardous wind shear conditions in the airport terminal area. To meet these objectives, scan strategies to efficiently cover the protected airspace were developed after extensive testing at several sites with different meteorological environments. Since the topology and geometry differ at each ... |
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| Evaluation of an Unlighted Swinging Airport Sign |
AUG 94 |
13 pages |
| Authors:
Eric S. Katz; FEDERAL AVIATION ADMINISTRATION TECHNICAL CENTER ATLANTIC CITY NJ
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| An unlighted swinging airport sign was evaluated at the Federal Aviation Administration Technical Center. The purpose of the evaluation was to determine the readability of the sign under varying wind and jet blast conditions. Results indicate that the sign is readable under all of the test conditions except when subjected to wind speeds of approximately 35 to 40 knots with gusts produced by the additive effect of the ambient winds ... |
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| Experiment on Rapidly Intensifying Cyclones Over the Atlantic |
03 JUN 94 |
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| Authors:
Robert A. Weller; WOODS HOLE OCEANOGRAPHIC INSTITUTION MA
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| This is a Final Report on Contract N00014-90-J-1423, which was our participation in ERICA (the Experiment on Rapidly Intensifying Cyclones over the Atlantic). The goal of the Experiment on Rapidly Intensifying Cyclones over the Atlantic (ERICA) field study was to obtain new understanding of the physical mechanisms and processes that account for the wintertime phenomenon of explosively developing extratropical cyclones over the North Atlantic Ocean. The intensive field program ran ... |
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| Cold Regions Performance of Optical-Fiber and Pulsed Near-Infrared Intrusion Detection Systems |
MAY 94 |
47 pages |
| Authors:
Lindamae Peck; COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH
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| Four optical-fiber intrusion detection systems (IDSs) and one pulsed near infrared IDS were operated from October 1992 through July 1993 during conditions of snowfall and rainfall, unfrozen and frozen ground, snow as deep as 80 cm, wind gusts >20 m/s, and air temperatures ranging from -30 deg C to 350C. The optical-fiber IDSs were installed in both buried and fence-mounted configurations. The detection capability of the IDSs was determined with ... |
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| ASR-9 Microburst Detection Algorithm |
22 OCT 93 |
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| Authors:
O. J. Newell; J. A. Cullen; MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB
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| The ASR-9 Wind Shear Processor (WSP) is intended as an economical alternative for those airports that have not been slated to receive a Terminal Doppler Weather Radar(TDWR) but have, or will be receiving, an ASR-9 radar. Lincoln Laboratory has developed a prototype ASR-9 WSP system which has been demonstrated during the summer months of the past three year in Orlando, Florida. During the operational test period, microburst and gust front ... |
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| Operational Test and Evaluation (OT&E) Operational Air Traffic Control Evaluation Plan for the Prototype Airport Surveillance Radar Wind Shear Processor (ASR-WSP) at Albuquerque International Airport |
OCT 93 |
26 pages |
| Authors:
Patrick Martin; Bruce Ware; FEDERAL AVIATION ADMINISTRATION TECHNICAL CENTER ATLANTIC CITY NJ
|
| The Massachusetts Institute of Technology, Lincoln Laboratories (MIT- LL), operating in support of the Federal Aviation Administration (FAA) Terminal Radar Program has developed a prototype Wind Shear Processor (WSP) modification to interface with Airport Surveillance Radars (ASR) 8 and 9. The WSP enables the ASR radars to automatically detect low altitude wind shear phenomena such as microbursts and gust fronts. This plan describes the methods, procedures, roles, and responsibilities in ... |
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| Integrated Terminal Weather System (ITWS) 1992 Annual Report |
07 SEP 93 |
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| Authors:
James E. Evans; MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB
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| Hazardous weather in the terminal area is the major cause of aviation system delays as well as a principal cause of air carrier accidents. Several systems presently under development will provide significant increases in terminal safety. However, these systems will not make a major impact on weather- induced delays in the terminal area, meet a number of the safety needs (such as information to support ground deicing decisions), or reduce ... |
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| Development of an Air-to-Air Refueling Automatic Flight Control System Using Quantitative Feedback Theory |
JUN 93 |
127 pages |
| Authors:
Dennis W. Trosen; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING
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| Quantitative Feedback Theory and the improved method Quantitative Feedback Theory are enhanced to include the rejection of disturbance at the system output. The enhanced Quantitative Feedback Theory and improved method Quantitative Feedback Theory processes are applied to the design of an automatic flight control system to regulate position of the C-135B fuel receiving aircraft relative to the tanker during air-to-air refueling. A simple feedback control system is developed that will ... |
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| Contributions to the American Meteorological Society's 26th International Conference on Radar Meteorology at Norman, Oklahoma, on May 24-28, 1993 |
01 APR 93 |
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| Authors:
Marilyn W. Wolfson; MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB
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| The work reported included Terminal Doppler Weather Radar (TDWR), Air Surveillance Radar-9, Integrated Terminal Doppler Weather Radar Surveillance Systems (TASS). The staff members of the Weather Sensing Group have documented their studies in four major areas: Operational Systems (TDWR Operational Test and Evaluation results); Radar Operations (future airport weather surveillance requirements, a 'machine intelligent' gust front detection algorithm, microburst asymmetry study results, a shear-based microburst detection algorithm, and a hazard ... |
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| Final Report for the ATC Evaluation of the Prototype Airport Surveillance Radar Wind Shear Processor (ASR-WSP) at Orlando International Airport |
MAR 93 |
20 pages |
| Authors:
Martinez Radame; FEDERAL AVIATION ADMINISTRATION TECH- NICAL CENTER ATLANTIC CITY NJ
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| This report presents the results of the FAA's air traffic control (ATC) operational evaluation of an Airport Surveillance Radar Wind Shear Processor (ASR-WSP) which operated at Orlando International Airport (MCO) during the summer of 1992. The evaluation was conducted in order to obtain reaction to the ASR-WSP weather products and displays. It was concluded that the system is capable of meeting ATC operational needs and in general was rated as ... |
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| An Application of Singularity Analysis to a Heavy Precipitation Event |
93 |
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| Authors:
Barbara Lee Cieslik; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH
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| On 27 May 1987, a mesoscale convective complex (MCC) brought heavy rains and flash flooding to the central portion of Oklahoma. A two-pass Barnes analysis is used to analyze the rainfall data recorded by 29 raingage instruments in the Oklahoma raingage network. The precipitation analysis is compared with a singularity analysis of Doppler velocity data. The singularity analysis produced three separable classes of divergence singularities: (1) Divergence singularities associated with ... |
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| Turbulent Microfronts |
05 NOV 92 |
9 pages |
| Authors:
Larry Mahrt; OREGON STATE UNIV CORVALLIS
|
| The research work under this contract studied turbulence structures in the atmospheric boundary layer by focussing on microfronts. Microfronts are zones of sharp gradients which occur at the leading edge of wind gusts and upstream edges of thermals. The present work indicates that microfronts also result from convergence zones induced by horseshoe vortices and longitudinal roll vortices. The microfronts and their parent eddy structures account for the majority of the ... |
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| Storm Tracking for TDWR: A Correlation Algorithm Design and Evaluation |
14 JUL 92 |
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| Authors:
Edward S. Chornoboy; MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB
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| Storm Movement Prediction (SMP) is a proposed (future) product for Terminal Doppler Weather Radar (TDWR), aiding controllers by tracking storms approaching and passing through the terminal environment. Because the scan strategy (data acquisition) of TDWR has been critically designed to meet the needs of its primary function, which is the detection of hazardous low-altitude wind shear, there is the question of whether reliable storm tracking can be obtained from the ... |
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| Birds Mimicking Microbursts on June 2, 1990 in Orlando, Florida |
10 JUL 92 |
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| Authors:
M. A. Isaminger; MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB
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| During 1990 and 1991, the Terminal Doppler Weather Radar (TDWR) testbed collected Doppler radar measurements in Orlando, Florida in support of the TDWR Project. The main focus of the project is to develope algorithms that automatically detect wind shears such as microbursts anti gust fronts. While the primary goal of the TDWR is to detect scattering from raindrops, the sensitivity of the system allows for the detection of biological echoes ... |
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| Airport Surveillance Radar (ASR-9) Wind Shear Processor: 1991 Test at Orlando, Florida |
01 JUN 92 |
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| Authors:
M. E. Weber; MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB
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| An operational test of a Wind Shear Processor (WSP) add-on to the Federal Aviation Administration's airport surveillance radar (ASR-9) took place at Orlando International Airport during July and August 1991. The test allowed for both quantitative assessment of the WSP's signal processing and wind shear detection algorithms and for feedback from air traffic controllers and their supervisors on the strengths and weaknesses of the system. Thunderstorm activity during the test ... |
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| Wind-Speed Periodicity Study for Shemya AFB, Alaska |
APR 92 |
20 pages |
| Authors:
Christopher A. Donahue; AIR FORCE ENVIRONMENTAL TECHNICAL APPLICATIONS CENTER SCOTT AFB IL
|
| Describes results of a time series analysis of Shemya AFB, Alaska, in an attempt to identify high frequency periodicities (fluctuations with periods of less than 1 hour) in wind speed at Shemya AFB, Alaska. Peaks in the power spectra at low frequencies were filtered out, and the remaining peaks were tested for significance. None of the peaks in the spectra at high frequencies were found to be significantly different from ... |
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| Reduction and Analysis of F-111C Flight Data |
DEC 91 |
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| Authors:
P. Piperias; AERONAUTICAL RESEARCH LABS MELBOURNE (AUSTRALIA)
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| As part of a programme to determine inspection intervals for the stiffener runout regions of the upper plates of the wing pivot fittings of RAAF F-111 aircraft, the possible influence on crack growth of stores carried and of low and negative g-spectrum loading has been examined for reconnaissance aircraft, the remaining F-111 fleet and for aircraft A8-148. Derived gust loading spectra for the same F-111 groups have also been determined. ... |
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| On the Potential Use of the Terminal Doppler Weather Radar Gust Front Detection Algorithm on the WSR-88D System. Part 2: Detecting Non-Gust Front Convergent Weather Phenomena |
OCT 91 |
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| Authors:
Gregory J. Stumpf; NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION NORMAN OK NATIONAL SEVERE STO RMS LAB
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| This study examines the capability of the Gust Front Detection Algorithm (GFDA) developed for the Terminal Doppler Weather Radar (TDWR) system to detect other types of non-gust front weather phenomena which are associated with patterns of convergence in a Doppler-radar radial velocity field. The potential use of the GFDA as a nowcasting tool, a mesoscale forecasting tool, and as a tool to detect other kinds of aviation hazards besides gust ... |
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| Loading and Vibration Reduction through Active Aerodynamic Control |
13 SEP 91 |
14 pages |
| Authors:
John C. Simonich; UNITED TECHNOLOGIES RESEARCH CENTER EAST HARTFORD CT
|
| The objective of this work is to provide active aerodynamic control concepts for reducing propulsor blade unsteady lift and moments. These unsteady forces are responsible for vibration and noise during an encounter with an incident gust. This effort represents an extension of a recent UTRC breakthrough in which active aerodynamic control was used to reduce noise generated during a two dimensional (2-D) blade-gust interaction. The associated reductions in unsteady blade ... |
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| The 1990 Airport Surveillance Radar Wind Shear Processor (ASR-WSP) operational Test at Orlando International Airport |
17 JUL 91 |
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| Authors:
T. A. Noyes; S. W. Troxel; M. E. Weber; O. J. Newell; J. A. Cullen; MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB
|
| Lincoln Laboratory, under sponsorship from the Federal Aviation Administration (FAA), is conducting a program to evaluate the capability of the newest Airport Surveillance Radars (ASR-9) to detect hazardous weather phenomena--in particular, low-altitude wind shear created by thunderstorm- generated microbursts and gust fronts. The ASR-9 could provide coverage at airports not slated for a dedicated Terminal Doppler Weather Radar (TDWR) and could augment the TDWR at high-priority (high traffic volume, severe ... |
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| Manual on the Flight of Flexible Aircraft in Turbulence (Manuel sur le Vol des Avions Non-rigides en Milieu Turbulent) |
MAY 91 |
|
| Authors:
John C. Houbolt; ADVISORY GROUP FOR AEROSPACE RESEARCH AND DEVELOPMENT NEUILLY-SUR-SEINE (FRAN CE)
|
| The study of atmospheric turbulence and its influence on aircraft operation and design has been of concern almost continuously since the inception of AGARD. The past few years have seen a heightened interest in the turbulence or gust problem, particularly on analysis or reduction of turbulent encounter data, and on design procedures. The present publication constitutes a review document in which is distilled the experience of specialists from amongst the ... |
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| Terminal Doppler Weather Radar Operational Test and Evaluation, Orlando 1990 |
09 APR 91 |
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| Authors:
David M. Bernella; MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB
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| Lincoln Laboratory conducted an evaluation of the Federal Aviation Administration (FAA) Terminal Doppler Weather Radar (TDWR) system in Orlando. Florida during the summer of 1990. In previous years, evaluations have been conducted at airports in Kansas City, MO (1989) and Denver, CO (1988). Since the testing at the Kansas City International Airport, the radar was modified to operate in C-band, which is the intended frequency band for the production TDWR ... |
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| A Kalman Filter Integrated Navigation Design for the IAR Twin Otter Atmospheric Research Aircraft (Methode de Navigation Integree a Filtre de Kalman Destinee au Twin Otter de L'Ira Charge des Recherches Atmospheriques) |
APR 91 |
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| Authors:
B. W. Leach; NATIONAL RESEARCH COUNCIL OF CANADA OTTAWA (ONTARIO) INST FOR AEROSPACE RESEA RCH
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| The IAR Twin Otter Atmospheric Research Aircraft has a continuing requirement for more accurate, inertially-based navigation data for both track recovery and the calculation of wind gust components. This navigational accuracy is necessary, not just during post-flight analysis, but also for real-time, in- flight guidance and wind computation. Previous developmental work on advanced navigation systems has demonstrated the benefits of a Kalman filter integrated navigation approach in order to satisfy ... |
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GUSTS
