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         Geometry Aircraft:     more books (53)
  1. Technical report by M. D Dobson, 1968
  2. Aeroacoustic characteristics of a rectangular multi-element supersonic jet mixer-ejector nozzle (SuDoc NAS 1.26:195460) by Ganesh Raman, 1996
  3. Users manual for the improved NASA Lewis ice accretion code LEWICE 1.6 (SuDoc NAS 1.26:198355) by William B. Wright, 1995
  4. Aerodynamic shape optimization of a HSCT type configuration with improved surface definition progress report for the period ended June 30, 1994 (SuDoc NAS 1.26:197011) by A. M. Thomas, 1994
  5. Ultra-high bypass ratio jet noise (SuDoc NAS 1.26:195394) by John, K. C. Low, 1994
  6. Geometric modeling for computer aided design summary of research (final report) for the period ended June 30, 1995 (SuDoc NAS 1.26:198828) by James L. Schwing, 1995
  7. Computational methods for global local analysis (NASA technical memorandum) by Jonathan B Ransom, 1992
  8. Aircraft Carriers of the World: An illustrated guide to more than 140 ships, with 400 identification photographs and illustrations. From early kite balloon ... that carry variable-geometry jets, V/STOL by Bernard Ireland, 2008-01-25
  9. Computer-aided light sheet flow visualization using photogrammetry (SuDoc NAS 1.60:3416) by Kathryn Stacy, 1994
  10. HOMAR:a computer code for generating homotopic grids using algebraic relations users' manual (SuDoc NAS 1.26:4243) by Anutosh Moitra, 1989
  11. Radiant energy measurements from a scaled jet engine axisymmetric exhaust nozzle for a baseline code validation case (SuDoc NAS 1.15:106686) by Joseph F. Baumeister, 1994

61. Geometry Project
From geometry Generator to Numerical Simulation and Windtunnel tests. The geometry Generator E88 is designed especially for aircraft definition.
http://www.pagendarm.de/trapp/geometry/
From Geometry Generator to Numerical Simulation and Windtunnel tests
The Geometry Generator is designed especially for aircraft definition. A Series of different generators from this series support several aircraft speeds and configuration types.
Alternative Geometry Definition
The geometry definition is different from conventional CAD systems. First some 2 dimensional key curves are specified. The curves are compositions of different basic curves like arcs, quintics, splines etc. The keys specify characteristic lines such as the crownlines or planform of an airplane. Special functions calculate the 3 dimensional model from the 2 dimensional curves. The functions are specialized to the different configuration types such as low speed, transonic or supersonic transport. Special algorithms can be used for smooth connections between wings and bodies. We destinguish between wing-type and body-type parts. Proven airfoil sections from catalogs or which have already been tested, can be used for wing definition. The body cross sections are for example given by superelliptical functions, box type shapes or refined cross sections derived by special flow modelling calculations.

62. 2 Comparative Visualization
a side by side comparison of local surface curvature as well as a data level comparison of curvature difference between the right and left aircraft geometry.
http://www.pagendarm.de/trapp/library/hgpVis96/vis96-3.html
2 Comparative visualization
A classification of approaches in comparative visualization is presented in . These early examples emphasize the image level comparison. Data from different sources is displayed side by side using similar visualization technique to support straight forward comparison. Fig. 2 shows a comparison of the structured grid as it is generated from the geometry generation step compared to the unstructured tetrahedral CFD grid of an aircraft seen from the top as it is used for the numerical flow simulation. Note the different clustering of grid points which illustrates the flexibility of the grid generation tools to increase numerical accuracy in regions of interest. Fig. 2 Side by side comparison of the curvilinear grid from the geometry generation tool and the unstructured CFD grid. The configuration shows the wing-root section of an high wing aircraft from the top. A more elaborate image level comparison is obtained from performing pixel operations on the comparable images. For example, experimental Schlieren images may be superimposed on simulated Schlieren images of numerical flow solutions using a colour mapping This techniques allows to precisely visualize and quantify properties in the data such as the spatial displacement of features like a shock wave. The concept was extended to the use of skin-friction lines in comparative visualization

63. Barnes Wallis
If his designs for a variable geometry aircraft were continued Britain could have led the world in aircraft design but funds were not available.
http://freespace.virgin.net/ian.bayley/ARTICLES/wallis/wallis.html
Barnes Wallis
An Introduction To The Work of A Genius
by Ian Bayley
Barnes Wallis is one of Britain's great unsung heroes. Should his name be recollected at all it is usually associated with the bouncing bomb of world war two fame and then promptly forgotten. Yet this man whose life spanned from the early days of flight to the advanced jet engine had a gift of inventiveness coupled with design that was nothing short of genius. It is unfortunate that due to political wrangling, economic problems and a little bad luck he never received the recognition he deserved outside of a small group in the aeronautical industry. Born in 1887 of a middle class yet hard-up family, Barnes Neville Wallis was sixteen when the Wright Brothers made their first successful flight on 17th December 1903. This was not something that particularly attracted his attention and he left school in 1904 with little in the way of qualifications and no job. After an apprenticeship at an engineering company followed by work at a shipyard on the Isle of Wight Barnes finally came into contact with airships and on 1st September 1913 attained the post of Chief Assistant in the Vickers Airship Department. Although he was to remain surprisingly loyal to Vickers over the years to come, it was here that he encountered the political wrangling and government interference that was to frequently frustrate him. The R100 Airship - Built using a geodetic design Despite many obstacles, including several periods of unemployment, Barnes brought a fresh and unique approach to airship design. First by creating the R80 and then by producing the R100 which used geodetic principles in its production. These airships were unlike any others created but due to political reasons Barnes was to suffer the disappointment of seeing both of these unique craft scrapped within months of their launch

64. Russian Aviation Page: Nato Codenames For Soviet Aircraft
roles. Blackjack Tupolev Tu160 Long-range strategic bomber and maritime strike/reconnaissance aircraft. Variable-geometry wings.
http://aeroweb.lucia.it/~agretch/RAFAQ/NatoCodenames.html
Nato codenames for Soviet aircraft Russian aircraft codenames From rec.aviation.military FAQ by Ross Smith During the Cold War, it was common for the West to know (or suspect) that an aircraft existed in the Soviet inventory, but not know its correct designation. Even when the USSR released publicity pictures of their aircraft (or allowed Western journalists to film them flying past during displays), the aircraft's name was usually never mentioned. Because of this, a system of codenames was invented by NATO. Each type was given a name starting with "B" for bombers, "C" for cargo or passenger transports, "F" for fighters, "H" for helicopters, or "M" for miscellaneous (everything else). Fixed-wing aircraft received names with one syllable if they were propeller-driven, two syllables if they were jets (there is no rule for the number of syllables in a helicopter's codename). Variants were indicated by suffix letters (e.g. the fourth version of the MiG-25 "Foxbat" to be identified became "Foxbat-D"). With the modern opening up of the Russian military, it's becoming more common to refer to Russian aircraft by their real designations (now better known in the West). Some recent types haven't been given codenames, and the system seems likely to disappear altogether in the near future.

65. TWITT's Classified Advertising
VHS tape of Phil Barnes’ September 16, 1995 presentation on the Math Characterization and Visualization of aircraft geometry.” This can be packaged with a
http://members.cox.net/twitt/CLASSIFIEDS.htm
AVAILABLE DIRECTLY
FROM TWITT
VHS tape of Phil Barnes’
September 16, 1995 presentation on the "Math Characterization and Visualization of Aircraft Geometry.” This can be packaged with a 35 page booklet of all the charts and graphs covered by Phil. There is also a set (2) of audio cassettes of the talk if you don't want or need the video. Cost: VHS Tape $5.00 postage paid
Booklet $5.00 postage paid
Audio Tapes $4.00 postage paid
(Foreign orders add $3.00 for surface postage) VHS tape of Paul MacCready’s presentation on March 21,1998, covering his experiences with flying wings and how flying wings occur in nature. Tape includes Aerovironment’s “Doing More With Much Less”, and the presentations by Rudy Opitz, Dez George-Falvy and Jim Marske at the 1997 Flying Wing Symposiums at Harris Hill, plus some other miscellaneous “stuff”. Cost: $6.00 postage paid
(Foreign orders add $2.00 for surface postage)

66. Airport Ground Tracking Radar Tracker
this, the composite tracker needs a geometric definition of the relationships of the radar components to one another and to the geometry of the aircraft itself
http://www.wagner.com/technologies/datafusion/stickfigure.html
You are at: Wagner Home Stick-Figure Tracker
Airport Ground Tracking Radar Stick-Figure Tracker
This page describes a new tracking algorithm, called the Stick-Figure tracker, and the implementation of this tracker in prototype software. Contents Algorithm patented by
Joseph H. Discenza and C. Allen Butler,
Stick Figure Radar Tracking Process
Patent No. 5,300,933.
The Ground Traffic Radar Problem The ASDE-3 radar is a special purpose, high-resolution surface radar used to monitor the movement of airport ground traffic. Because of the ratio of target size to radar range, a jetliner can return energy in a very large number of range and bearing sample bins. Moreover, because of differences in reflectivity, the target may actually appear in the data as two or more smaller returns rather than one large one. In some cases, the radar picture may look very much like the plan view of the aircraft itself, while, in others it may not.
Depiction of radar return from a large jetliner on a runway.

67. Air Force Technology - MiG-27K (MiG 23) Flogger - Fighter Bomber Aircraft
The MiG27K variant of the MiG-27 family is a variable geometry wing fighter bomber. The primary mission of the aircraft is the destruction of moving and
http://www.airforce-technology.com/projects/mig27/
Return to Industry Projects Index
MIG-27K (MIG 23) FLOGGER FIGHTER BOMBER AIRCRAFT, RUSSIA
The MiG-27K fighter bomber aircraft is manufactured by RSK MiG and the Irkutsk Aircraft Production Association Joint Stock Company. Both the MiG-23 fighter aircraft and the MiG-27 fighter bomber aircraft are sometimes referred to by the NATO codename Flogger. The MiG-27K variant of the MiG-27 family is a variable geometry wing fighter bomber. The primary mission of the aircraft is the destruction of moving and stationary, fixed and mobile, ground targets, including hardened targets. The Indian Navy has plans to order 50 MiG-27K fighters to operate from the Admiral Gorshkov aircraft carrier being acquired from Russia. MISSILES The aircraft carries three types of air-to-surface missile. The Kh-23M air-to-surface missile (NATO codename AS-7 Kerry) is supplied by the Zvezda-Strela State Research and Production Center, Moscow. Kh-25ML (NATO designation AS-12 Kegler), also supplied by Zvezda, has semi-active laser guidance and the range is between 2.5-10km. The missile is equipped with a high-explosive (HE) 86kg warhead. The Kh-29ML (NATO designation AS-14 Kedge), built by Vympel, uses semi-active laser guidance and has a range up to 10km. The missile is equipped with a 317kg penetrating warhead. The anti-radar missile is the Zvezda Kh-27PS (NATO designation AS-12 Kegler).

68. Aircrew Sitting Geometry In Fighter Aircraft Cockpit.
Kapur RR; Seshanna SV; Krishnaswamy KN. Aircrew Sitting geometry in fighter aircraft cockpit. Indian Journal of Aerospace Medicine. 1988 Dec; 32(2) 7780.
http://medind.nic.in/imvw/imvw20772.html
Extracted from IndMED Kapur RR; Seshanna SV; Krishnaswamy KN Aircrew Sitting geometry in fighter aircraft cockpit. Indian Journal of Aerospace Medicine. 1988 Dec; 32(2): 77-80 ABSTRACT: Sitting posture of a pilot is influenced by the back tangent angle of the crewseat which in turn effects the slouch and head orientation required to keep the line of sight horizontal. MIL STD-1333A defines the crew seating geometry based on anthropometric data of USAF pilot population. This paper describes the methods used to adopt MIL STD-1333A to suit IAF pilot anthropometric data for establishing seat geometry in a fighter aircraft cockpit. KEYWORDS: Posture/PH; Aircraft; Military Personnel; Anthropometry; Head Human Engineering; Aerospace Medicine; Movement; Analysis of Variance; Human; India References: 6 Record Identifier: NI001909

69. About "Historical Developments Of The Aircraft Industry With Mathematical Applic
Historical Developments of the aircraft Industry with Mathematical Applications. unit written as an enrichment lesson for students in basic geometry or geometry
http://mathforum.org/library/view/11884.html
Historical Developments of the Aircraft Industry with Mathematical Applications
Library Home
Full Table of Contents Suggest a Link Library Help
Visit this site: http://www.cis.yale.edu/ynhti/curriculum/guides/1990/7/90.07.10.x.html Author: Hermine E. Smikle - Yale-New Haven Teachers Institute Description: A unit written as an enrichment lesson for students in basic geometry or geometry; also, the section on spherical geometry can be used in an Algebra II Trigonometry class as an extension or an introduction to spherical geometry. It includes an introduction to graph theory. Levels: High School (9-12) Languages: English Resource Types: Lesson Plans and Activities Math Topics: Graph Theory Higher-Dimensional Geometry Euclidean Plane Geometry History and Biography ... Contact Us
http://mathforum.org/

70. Desktop Aeronautics Catalog
The aircraft wing geometry, cruise conditions, tail configuration, seating layout, propulsion system and range are chosen by clicking on a variety of options.
http://www.desktopaero.com/catalog.html
Home
New!

Order Form
Demos

Manuals

FAQ's

Company
...
Information

This page contains short descriptions of our products and links to more detailed information. An order form is available here and rather than transmit credit card information on the internet, we ask that you fax a completed copy of the order form to (650) 424-8589, or call us at (650) 424-8588.
Programs for Aerodynamic Analysis and Design
PANDA Program for Analysis and Design of Airfoils Computes pressures on arbitrary sections from coordinates in an ASCII file. Karman-Tsien compressibility effects. Integral boundary layer calculations for transition location, laminar and turbulent separation, and drag. Design option permits interactive changes in airfoil geometry with recalculation and display of pressures in less than a second. Built-in plotting of Cp or save results to Plot file. Available for MacOS and Windows. LinAir 1.4 Multiple nonplanar lifting surface analysis program Computes aerodynamic characteristics of complete configurations. A discrete vortex Weissinger program with up to 5 linearly tapered and twisted elements, 40 panels per element. Quadratic profile drag integration and Trefftz-plane induced drag computation. Easy-to-use interface, built-in plotting and 3-D geometry display. Perfect for computing interference of wing and canard, aft tail, or winglets. Available for MacOS and Windows.

71. Continuous Moldline Technology
Researchers are developing the application of a highly flexible structure to enable adaptation of aircraft geometry to different flight conditions and mission
http://www.afrlhorizons.com/Briefs/Dec02/VA0203.html
Continuous Moldline Technology
Researchers are developing the application of a highly flexible structure to enable adaptation of aircraft geometry to different flight conditions and mission requirements for future morphing aircraft.
AFRL's Air Vehicles Directorate, Structures Division and Aeronautical Sciences Division, Wright-Patterson AFB OH Adaptive structures technology development is currently of high interest in aeronautics, evidenced by many activities at the Defense Advanced Research Projects Agency, the National Aeronautics and Space Administration (NASA), and AFRL. Recent technology developments in compact actuators are providing a foundation for future adaptive structures applications. Some advanced materials enable an integral structure and actuation mechanism. The development of highly flexible structures, such as CMT, is also enabling to future adaptive structures applications. As shown in Figure 1, CMT consists of an elastomeric matrix, reinforced with stiffening rods that are able to slide within the matrix to achieve very high deformation. Researchers demonstrated CMT structures to 30% elongation and compression as well as very large bending and twisting deformation. CMT offers substantial performance payoffs for numerous applications. Variable geometry fuel cells and inlets are two notable examples where CMT can reduce aerodynamic drag throughout a mission profile (see Figure 2). Also, application of CMT to bridge the gap between movable control surfaces and fixed wing structure improves the aerodynamic effectiveness of the control surface and can reduce the noise generated by the unsealed gap. While it is easy to see how an adaptive structure can improve aerodynamic performance, the key to realizing these aerodynamic benefits on an air vehicle is to minimize any penalties associated with the adaptive structure versus a conventional structure. Weight, cost, and actuation power requirements are all potential penalties that could limit the effectiveness of CMT applications. In order to fully evaluate the benefits and penalties for CMT, researchers needed to fabricate and test large-scale hardware in a relevant environment.

72. Gallery
This photo shows the laser formed Ti6Al-4V machining preform which protects the final geometry of the aircraft fitting illustrated above.
http://www.aerometcorp.com/Gallery.htm
Gallery Fully machined aircraft structural "Keel", (Titanium 6Al-4V), (L)aser (A)dditive (M)anufactured by AeroMet Corporation for the Boeing Company and exhibited at the Defense Manufacturing Conference, November 2001 in Las Vegas, Nevada. Image shown courtesy of the Boeing Company. Frank Arcella, CTO and Founder, AeroMet Corporation with fully machined aircraft structural "Spar" (Titanium 6Al-4V) LAM manufactured by AeroMet Corporation for the Boeing Company and exhibited at the Defense Manufacturing Conference, November 2001 in Las Vegas, Nevada. Image shown courtesy of the Boeing Company. The Laser Additive Manufacturing technique used by AeroMet to rapidly manufacture full scale aircraft components is illustrated in the following figures. The Laser Additive Manufacturing technique used by AeroMet to rapidly manufacture full scale aircraft components is illustrated in the following figures. The sample parts in the photo to the left illustrate the different types of geometries which have been laser formed at AeroMet. Some specific examples are described in greater detail below. A typical aerospace component is pictured at left in the as-formed and machined (inset) condition. This machining preform is approximately 36 inches (900 mm) in length. Protruding features such as stiffener ribs and bosses were deposited onto both sides of a conventional baseplate, with the baseplate providing the material for the webbing of the final machined structural component. Savings of 20-40% have been forecast for these components versus conventional approaches.

73. FSGateway.com Tips
clicking it. Go down to the aircraft geometry section and write down the values for wing_incidence and wing_twist. Now calculate
http://www.fsgateway.com/tips_read.asp?id=539

74. Aircraft Designs, Inc: Index.
Many projects such as; the variable wing geometry, high speed aircraft, the Lancair and Stallion, the jump start gyroplane, the Acro 1 have required special
http://www.aircraftdesigns.com/designing_aircraft.html
Stallion FREE Software Classes Gyroplanes ... Contact
DESIGNING AIRCRAFT The conceptual design phase is the most important part of the design process. It consists of:
  • Making a wish list of what the aircraft will do. This is a preliminary specification. Size lifting and control surfaces. Select and design airfoils. Many projects such as; the variable wing geometry, high speed aircraft, the Lancair and Stallion, the jump start gyroplane, the Acro 1 have required special airfoils. Make a three view drawing of aircraft. Make an inboard profile layout showing location of all major components. Perform a weight and balance and stability check and rearrange components to meet requirements. Calculate performance. Make an isometric drawing to show what aircraft looks like. Final aircraft specification.

Once the conceptual design is completed, the structural design can be started. This includes:
  • Perform structural design, sizing and optimization. Design fixed or retractable landing gear. Design pressurized hull and system. Make detailed layouts using drafting and CAD systems.

75. Mty24.htm, AIRPORTS - Airport Geometry
AIRPORTS Airport geometry. An airport provides takeoff, landing, and parking for aircraft. It also allows interchange between air
http://www.unb.ca/web/transpo/mynet/mty24.htm
AIRPORTS - Airport Geometry
An airport provides takeoff, landing, and parking for aircraft. It also allows interchange between air transport service and other modes. Current commercial and private aircraft can remain airborne for relatively short periods of time. Only orbiting spacecraft overcome this limitation. Lighter than airships can remain in the air for long periods, but at present they are not important transport vehicles. The characteristics of the aircraft and traffic dictate the requirements. Airports began their evolution with the early flights by the Wright brothers. Early airports catered mostly to the small airplanes of the time. They required a relativly flat even surface so that straightline takeoffs and landings could take advantage of the wind conditions present when a landing or takeoff was attempted. High traffic airorts usually serve large metropolitan areas. Ideal airline service is nonstop direct from origin to destination airports. This usually means that ideally there are a range of traffic loads and trip lengths that vary from the smallest to the largest practical aircraft capacities and flight distances. Many studies have shown that air travel cannot compete with surface modes when the surface time is about two hours or less. For even three or four hour surface trips air travel may not be competitive. With current aircraft and ground transport speeds the critical unencumbered distance is between 300 and 400 km.

76. Airphoto Geometry
century. Aerial photography can be conducted from space, high or low altitude aircraft, or near ground platforms. Airphoto geometry. Airphotos
http://www.fes.uwaterloo.ca/crs/geog165/apg.htm
Airphoto Geometry
Home Scope of Remote Sensing Remote Sensors Airphoto Interpretation ... Height Calculation
Recommended Readings
Campbell, J. (2001) Map Use and Analysis, Chapter 17, pp 253-268. Avery, T. E. and Berlin, G. L.. (1992) Fundamentals of Remote Sensing and Airphoto Interpretation, Chapter 4, pp 71-81.
Aerial Photography
Airphotos have been an important source of data for mapping since the first decades of the 20th century. Aerial photography can be conducted from space, high or low altitude aircraft, or near ground platforms. Aerial photographs are acquired using a photographic camera an film to record reflected EMR within the camera's field of view. This is an optical-chemical system in which the lens focuses EMR on the film which is coated with a light sensitive emulsion that detects reflected EMR in the wavelength band from 0.3 m m to 0.9 m m, i.e., from the mid ultra-violet to the near IR range. The result is a continuous tone photograph that has high spatial resolution (i.e. shows fine spatial detail) but low spectral resolution (i.e., is sensitive to EMR in a broad spectral band). The entire scene within the camera's field of view is processed instantaneously. However, there distortion in the image due to the fact that it is a perspective rather than planimetric view of the surface. A variety of films and film formats can be used to acquire airphotos. The most common film format is 35 mm which is the standard slide or colour print film. Larger formats such as 70 mm are available and have the advantage of recording greater spatial detail. Most airphotos used for mapping are obtained using a 23 cm x 23 cm metric mapping camera. This large image size maximizes the spatial detail that can be captured on the image.

77. UFO Geometry 101Pentagons Triangles - Update 5/24/99
UFO geometry 101Pentagons Triangles. We were just out in a car listening to the radio when we noticed a pentagonalshaped aircraft with red lights along
http://www.caus.org/flytriangle/ft052499.shtml
CAUS Update
"The search for knowledge implies also a duty; one must never hide what one has found to be the truth." -Albert Einstein On this Monday, CAUS shares with you three more reports of the strange and mysterious objects that are continually seen in our skies and of which the Department of Defense tells us...it knows nothing about: 1) CAUS thanks Shanil Virani (shanilv@yahoo.com) for this report: 2) CAUS thanks George Filer (Majorstar@aol.com) Filer's Files #20 1999, May 21, 1999, (609) 654-0020; for these two reports: LOUISIANA
SOUTH CAROLINA
Shame on you Department of Defense for all the lies! References Shanil Virani ( shanilv@yahoo.com
George Filer ( Majorstar@aol.com HOME SUPPORT CAUS CONTACT CAUS ... MAILING LIST The PAG Network
Box
Sedona, AZ 86339
Phone: 520-203-0567
e-Mail: ufolawyer1@aol.com
2001. All Rights Reserved Send CAUS Comments and Reports to: CAUS@CAUS.ORG
Webmaster

78. Russian And Soviet Military Aircraft
Su24, Sukhoi Fencer , A variable geometry strike/attack aircraft, obviously inspired by the US F-111, but more optimized for the low-level tactical strike role
http://www.armscontrol.ru/atmtc/Arms_systems/Avia/Russia/Sukhoi_Aircraft.htm
Russian and Soviet Military Aircraft
  • SUKHOI DESIGN BUREAU, Moscow, Russian Federation

BB-1, Sukhoi Renamed Su-2 I-107, Sukhoi See Su-5 I-330, Sukhoi See Su-1 I-360, Sukhoi See Su-3 P-1, Sukhoi Experimental fighter. The P-1 was a tailed two-seat delta. It had oval jet intakes just ahead of the wing root, with twin shock cones. Armament was rectractable rocket launchers in the nose, behind the radar. The big P-1 was underpowered with the single Lyulka AL-7F engine. No production.
Type: P-1
Function: fighter

Year: 1958 Crew: 2 Engines: 1 * 10600kg Lyulka AL-7F
Wing Span: 9.50m Length: 21.30m Height: Wing Area:
Empty Weight: Max.Weight:
Speed: 2050km/h Ceiling: 19500m Range: 2000km
Armament: 50*r57mm 1*g37mm P-42, Sukhoi A stripped version of the Su-27 , without armament or electronics, used to set time-to-height records. PT-7, Sukhoi Development of the T-3 with a variable-geometry inlet. PT-8, Sukhoi A development of the Su-9 series, and prototype for the Su-11 S-1, Sukhoi Prototype of the Su-7 S-2, Sukhoi Prototype of the Su-7.

79. Towards Prediction Of Aircraft Spin
Towards Prediction of aircraft Spin. geometry description and grid generation, numerical solution of the NavierStokes equations, and efficient postprocessing
http://www.navo.hpc.mil/Navigator/Fall01_Feature3.html
Kyle D. Squires, Arizona State University
James R. Forsythe, United States Air Force Academy
Kenneth E. Wurtzler, William Z. Strang, Robert F. Tomaro, Cobalt Solutions, LLC
Philippe R. Spalart, Boeing Commercial Airplanes
Towards Prediction of Aircraft Spin
Most of the flow fields encountered in Department of Defense applications occur within and around complex devices and at speeds for which the underlying state of the fluid motion is turbulent. While Computational Fluid Dynamics (CFD) is gaining increased prominence as a useful approach to analyze and ultimately design configurations, efficient and accurate solutions require substantial effort and expertise in several areas. Geometry description and grid generation, numerical solution of the Navier-Stokes equations, and efficient postprocessing are all key elements. While advances have taken place in areas such as grid generation and fast algorithms for solution of systems of equations, CFD has remained limited as a reliable tool for prediction of inherently unsteady flows at flight Reynolds numbers. Current engineering approaches to prediction of unsteady flows are based on solution of the Reynolds-averaged Navier-Stokes (RANS) equations. The turbulence models employed in RANS methods necessarily model the entire spectrum of turbulent motions. While often adequate in steady flows with no regions of reversed flow, or possibly exhibiting shallow separations, it appears inevitable that RANS turbulence models are unable to accurately predict phenomena dominating flows characterized by massive separations. Unsteady, massively separated flows are characterized by geometry-dependent and three-dimensional (3D) turbulent eddies. These eddies, arguably, are what defeat RANS turbulence models of any complexity.

80. Jammer Effectiveness Model
The four scenario types in the communication geometry description are groundto-ground, ground-to-satellite, ground-to-aircraft, and aircraft-to-satellite.
http://www.its.bldrdoc.gov/tpr/2000/its_e/jem/jem.html
Jammer Effectiveness Model
Outputs
Aircraft with standoff and self-screening jammers avoiding detection by a shipboard fire-control radar and radar-guided missiles (illustration by A. Romero).

  • Multiple jammer and interferer analysis capability on a wireless network for use in performance evaluation in an electronic warfare or interference electromagnetic environment.
JEM uses scenario descriptions to completely characterize a communication link or radar configuration with or without a jamming situation. Data entry to create a scenario description is simplified by the use of user-friendly menus and options. Each scenario description is saved in a database, and includes: ground or airborne station location, three-dimensional geometry description, equipment characteristics, and physical factors such as climate and terrain. JEM contains an inventory of specific analyses that can be performed on the physical configurations represented by the scenario description data. The jamming and jammer versus network scenarios are the major features of JEM for electronic warfare and interference analysis. The other four scenario types are used to help evaluate and design microwave communication systems. They allow the user to simulate a wide variety of propagation effects on the system that occur in the higher frequency ranges by including clear-air absorption losses and losses due to rain attenuation. In FY 2000, three-dimensional antenna pattern capability was added to JEM. The radar version of JEM allows radar analysis for different combinations of radars and jammers that are on the ground or carried by airborne stations. The radar scenario analyses consist of evaluating the performance of a radar trying to detect and track a target. The analyses can be performed both with and without the presence of a jammer. A scenario includes the jamming of an airborne radar by a ground-based or airborne jammer to protect potential targets that can either be collocated with the jammer or separated from the jammer. The three-dimensional geometry of these radar scenarios requires three-dimensional antenna patterns, included in the analysis models.

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