LINKS

last updated September 2009

The "Links" page is even more eclectic than the rest of the Aeroexperiments website! Nonetheless there is some logical order to the arrangement of the links. Take some time to explore and you may find something of interest to you.

Click here to skip down to the weather links
Click here to skip down to the weather cameras

Click here to skip past the "dynamic soaring" links

Dynamic soaring links: a widespread, steady, updraft or downdraft or headwind or tailwind or crosswind has no effect whatsoever on the force vectors generated by an aircraft flying at a given airspeed in a given direction. However, transient gusts or gradients or shears do affect the force vectors generated by an aircraft flying in a given airspeed in a given direction. "Dynamic soaring" is the exploitation of gusts or gradients to extract energy from the atmosphere. In some cases, an aircraft or bird using "dynamic soaring" techniques can stay aloft indefinitely in unpowered flight even while flying in an airmass that is entirely devoid of updrafts. (For a bit more theory, see www.aeroexperiments.org/dynamicsoaring.shtml.)

Dynamic soaring "type 1": RC model gliders dynamic soaring on the lee side of a hill:

"Dynamic Soaring--the challenge" by Klaus Weiss--a practical article on the lee-side-of-the-hill form of dynamic soaring practiced by RC glider pilots

"Dynamic Soaring (DS) -- the hottest development in R/C soaring in many years!"--another practical article on the lee-side-of-the-hill form of dynamic soaring practiced by RC glider pilots

"How and why does dynamic soaring work?" by Mark Drela--a brief technical article on the lee-side-of-the-hill form of dynamic soaring practiced by RC glider pilots

"Dynamic Soaring on Back Side of Hill"--an illustration for the above article

"Dynamic Soaring"--another brief article, with some technical notes, on the lee-side-of-the-hill form of dynamic soaring practiced by RC glider pilots

"Dynamic Soaring Observations" from NorCal slope soaring--practical tips on dynamic-soaring RC models on the lee side of the hill

"Dynamic Soaring"--More practical tips on dynamic-soaring RC models on the lee side of the hill, along with downloadable video clips

Sample clip from "Lift ticket"--video illustrating RC gliders dynamic-soaring on the back side of the hill

Video clip from North Country Flying Machines illustrating an RC glider dynamic-soaring on the back side of the hill

"Dynamic Soaring video clips"--many more video clips from North County Flying Machines of RC gliders soaring on the back side of the hill (also includes some other types of soaring, not always clear from titles what is being depicted)

First page from "Preliminary Dynamic Soaring Research using a Radio Control Glider" by James Parle--a very technical exploration of dynamic soaring on the lee side of a hill. For more see this link

Dynamic soaring "type 2": using heading changes and "zoom climbs" for "cross-country" travel within the wind gradient over flat ground or over the ocean, as practiced by the albatross :

"Dynamic Soaring"--a simple article, with an animated illustration, about the form of dynamic soaring practiced by the albatross

"How Flies the Albatross: the flight mechanics of dynamic soaring" by J. Phillip Barnes--a fascinating, in-depth article about the form of dynamic soaring practiced by the albatross

An exploratory analysis of dynamic soaring: trajectories in shear layers" by Misty Davies -- a very technical exploration of the form of dynamic soaring practiced by the albatross

Dynamic soaring "type 3": various ways to use transient gusts, and to use the transition between still air and lift or sink, far from the earth's surface, such as are now being explored by full-scale sailplane pilots:

"Dynamic Soaring and Sailplane Energetics" by Taras Kiceniuk--an article introducing the basic principles of soaring without lift

"Calculations on Soaring Sink" by Taras Kiceniuk--an in-depth article on extracting energy from the transitions between still air and sinking air

"Dynamic Soaring of Sink Pockets" by Taras Kiceniuk--an illustration for the above article

"Vector diagram of dynamic soaring: showing how a glider can get energy from a downward gust" by Taras Kiceniuk--an illustration for the above article

"Side gust soaring" by Taras Kiceniuk--an illustration showing how a glider can extract energy from a sideways gust

Dynamic soaring "type 4": combining various ways to use transient gusts and transitions between still air and lift or sink, with a knowledge of fine-scale meteorology:

"Understanding Microlift" from September 6 2002 OZ report--notes from G. Osaba

More notes on putting various types of "dynamic soaring" into practice in full-scale sailplanes:

Extracts from "For Pilots" discussion group: #1

Or in spacecraft...

More dynamic soaring links:

Autonomous dynamic soaring platform for distributed mobile sensor arrays" by Mark B.E. Boslough -- a very technical exploration of various types of dynamic soaring, including the technique used by the albatross and the technique used by RC glider pilots on the lee side of hills

(End of dynamic soaring links)

Home page of the Experimental Soaring Association (formerly the Sailplane Homebuilders Association)

"A self-sustaining, boundary-layer adapted system for terrain exploration and environmental sampling" by C. Woolsey, G. Hagerman, and M. Morrow--buoyancy-driven glider for use on other planets

National Geographic news clip on NASA's autonomous sailplane UAV project

"Bird Flight Website"--elementary introduction to some principles of the soaring and flapping flight of birds, insects, etc.

"Making Pterodactyls Fly"--the fascinating story of the interdisciplinary exercise in paleoaerodynamics headed by Dr. Paul MacCready of Aeroenvironment that created a flying replica of the giant Quetzalcoatlus Northropi pterodactyl. Interesting points include the inherent aerodynamic instability of the design, the use of variable sweep for active pitch stabilization and trim, the use of the head as a canard rudder, the use of the claws as yaw dampers, the sideslip-related stability issues, the stability issues related to flapping flight, and much more.

"Found: the flying lizards’ missing lift"--a recent discovery in pterosaur morphology and aerodynamics, from the "New Scientist".

"Adaptive airfoils"--a fascinating website discussing variable-geometry sails for sailboats and windmills, and the evolution of winged flight in the natural world. Note the suggestion on the "wing geometry" page that the bi-conical shape used in hang glider wings (and many birds wings?) contributes to stability in all axes.

www.twitt.org --"The Wing is the Thing"--This site contains links to a vast array of material pertaining to flying-wing aerodynamic theory, historical and recent flying-wing sailplanes and airplanes, and other related topics. Some samples: "New ideas on bird flight", radio-controlled model Turkey Vultures, Seagulls, and Pelicans, "Bird Oriented Design Concept", Kasperwing page, BKB-1 sailplane

"Flying Wings" by Henry Cole--bird-inspired design

"The Development of All-Wing Aircraft" by John K. Northrop -- This is the 35^th Wilbur Wright Memorial Lecture. Note in particular the comments on yaw and roll dynamics, and the reference to the very small aerodynamic sideforce ("crosswind derivative") developed by an all-wing aircraft during a sideslip.

"The Nurflugel Pages" -- This is a great website on flying wings, and contains many interesting technical and historical articles. Two of the many links from these pages are given immediately below.

"A retrospective: flying wing design issues" by Albion H. Bowers and David A. Lednicer -- a highly readable survey of the challenges facing designers of flying-wing aircraft and the solutions that have been tried in the past.

"On the importance of the correct C.G. location in flying wings" by Dr. Karl Nickel -- This is an interesting little article; among other things Dr. Nickel notes that washout tends to decrease an aircraft's spiral instability or promote roll stability.

"Swept Wings and Effective Dihedral" by Bill and Bunny Kuhlman -- I've recently found this link; it is a paper that is absolutely central to many of the ideas discussed on the Aeroexperiments website.

"On the Wing #4"--this superb issue contains a series of technically complete, yet highly readable articles on twist distributions for swept-wing flying-wing aircraft. Article #3 of the series describes how the right twist distribution can minimize adverse yaw. It appears that Bill and Bunny Kuhlman are the authors of all the articles in this series.

"On the Wing #3"--another superb issue. Check out the article on the function of birds' tails, and the article about the merits of plank wings versus swept wings, and the article about trimming plank wings, and the article about control surfaces for flying wings, and more.

"On the Wing #2"--another superb issue. Check out the article on Steve Morris and the Swift, the article on the Me-163 Komet, the Zagi review, and much more.

"On the Wing #1"--yet another superb issue. Check out the article on the XB-35 and XB-49, and the articles on the pitch stability dynamics of swept wings and plank wings, and much more.

"Calculation of Equivalent Dihedral Angle" by Blaine Beron-Rawdon, from the rc-soar website. Describes how to quantify the effective dihedral of a polyhedral wing by calculating an Equivalent Dihedral Angle that considers the moment-arm and dihedral angle of each wing panel.

"Spiral Stability Augmentation with a Piezo-Electric Rate Gyroscope" by Blaine Beron-Rawdon, from the rc-soar website. Includes consideration of the roll torque created by the difference in wingtip airspeeds in a circling aircraft which is greatest at 45 degrees of bank, gives notes (and equations) for tuning the design of a sailplane by adjusting dihedral angle and vertical tail moment to achieve neutral spiral stability or any other desired degree of spiral stability or instability, notes that the rolling-in tendency is greatest at high lift coefficients, describes how to use a gyro to increase the spiral stability of a conventional 6-servo radio-controlled sailplane to reduce pilot workload without sacrificing aerodynamic efficiency, cites related articles.

Global index for Martin Hepperle's "Aerodynamics for model aircraft" website-- lots of very good technical information here on a wide range of topics, including much airfoil data. In relation to flying wings, see especially "Basic design of flying wing models" which has some good, concise notes on twist and planform and stability and control, "Airfoils for flying wings", and "Airfoils for tailless airplanes: design and selection"

"The stability of model aircraft--a non-mathematical treatment"--this article by Albert Debono gives a very concise description of the basic dynamics and stability mechanisms in the pitch, yaw, and roll axes. Note especially Figure 3 which illustrates the stabilizing roll torque created by dihedral during a sideslip, Figure 4 which illustrates the destabilizing roll torque created by anhedral during a sideslip, Figure 5 which illustrates the stabilizing roll torque created by sweep during a sideslip, and the descriptions of the "Pendulum effect" and of "Directional or Weathercock stability" at the end of the article.

John S. Denker’s "See how it flies" website—a truly superb and comprehensive presentation of physics-for-pilots, in the tradition of Langewiesche’s "Stick and Rudder". Aimed at primarily at conventional airplanes, but containing a great wealth of information about yaw stability, roll stability, coupling between yaw and roll due to dihedral or anhedral, rotational inertia in the yaw and roll axes, causes of adverse yaw, turn "coordination", rudder usage, pitch-axis dynamics, and much more.

"Theory of flight Level 3" from the Allstar network. A basic, straight-forward tutorial. See especially "How airplanes fly: a physical description of lift" (going beyond Bernoulli) and "Stability of an Airplane" (a concise, accurate description of the most basic principles of stability and control)

"Lateral stability". Another basic, straight-forward tutorial. Topics of interest include notes on roll damping, adverse yaw, the differential tip-speed effect, dihedral, high wing placement vs low wing placement, swept wing dynamics, Dutch roll, and the purpose of anhedral. I'm having trouble playing the accompanying movies. Includes navigation to other stability and control topics.

"Chapter 9: Stability and Control" from NASA's Sp-367 "Introduction to the Aerodynamic of Flight"--useful text and graphics. In particular, some basic concepts that are central to the themes discussed on the Aeroexperiments website are illustrated by these diagrams: static directional stability, directional stability moments, stabilizing effect of dihedral in the presence of a sideways (slipping) airflow component, effect of wing placement on lateral stability, stabilizing roll torque generated by sweep in the presence of a sideways (slipping) airflow component, sideslip plays a key roll in the stabilizing effect of dihedral (excessive directional stability contributes to spiral divergence), spoilerons have advantages over ailerons at high speeds

"Introduction to flight testing: steady sideslip" from Nasa Dryden flight research center. This page is directly related to some of the questions investigated on the Aeroexperiments website. Note however that in my experiments with rudders on flex-wing hang gliders, the required roll and bank inputs were both different than those illustrated on Figure SS-7 of this webpage. At most airspeeds, to stabilize the bank angle, a right rudder input needed to be matched with a right roll input: in other words the gliders exhibited a negative coupling between yaw (sideslip) and roll. (This is a net anhedral effect, which creates a roll torque in the opposite direction than does the net dihedral effect that is illustrated in Figure SS-1.) Meanwhile, the bank angle required to yield a linear (non-turning) flight path was very close to wings-level, and actually appeared to involve a very slight right bank. In other words, the sideways airflow over the aircraft created only a very small aerodynamic sideforce, and the sideforce (toward the left) created by the rudder itself may actually have been stronger than the sideforce (toward the right) created by the sideways airflow over the rest of the aircraft. These ideas are explored in more detail elsewhere on the Aeroexperiments website.

(Note that Figure SS-2 doesn't quite match the accompanying text--as drawn, this figure actually represents an aircraft in crabbed, non-slipping flight, with the green arrow representing the aircraft's ground track. There is no arrow showing the aircraft's flight path through the airmass--this arrow would point slightly toward the right of the runway heading, parallel to the aircraft's heading. If the figure accurately illustrated a normal crosswind landing using the sideslip method, the aircraft's ground track would still be aligned with the runway, and the aircraft's flight path through the airmass would still point to the right of the runway heading, but the nose of the aircraft would be pointing straight down the runway, because the pilot would be holding left rudder to yaw the aircraft's nose out alignment with the actual flight path through the airmass. The pilot would accompany this left rudder input with as much right bank as was needed to cancel out the aerodynamic sideforce created by the left rudder input, i.e. he would lower the right wing by whatever amount was required to create a linear, non-turning, flight path. In figure SS-2, the close proximity of the shadow appears to be meant to indicate that the aircraft is touching the runway. If the aircraft were to actually touch the ground in the crabbed, non-slipping attitude shown in the illustration, it would impose high side loads on the landing gear.)

"Introduction to flight testing: aileron roll" from Nasa Dryden flight research center. This page is also directly related to many of the questions investigated on the Aeroexperiments website. The page opens with a very concise description of the fundamental cause of a turn (but maybe not concise enough! To my mind, the reference to "increasing the lift vector" begs the question "Will the flight path still curve if the lift vector is not increased?") The page goes on to describe "the aerodynamic coupling that links the roll and yaw axes of an airplane through sideslip" that often leads to adverse yaw.

"Introduction to flight testing: control pulse" from Nasa Dryden flight research center. This page is also directly related to some of the questions investigated on the Aeroexperiments website. The importance of rotational inertia about all three axes is evident in the way that a single control pulse leads to a series of dynamic oscillations. Note the description of the way that the yaw and roll axes are coupled through sideslip, and the illustration of the way that a rudder (yaw) pulse leads to a rolling motion followed by a series of yaw-roll oscillations.

"Introduction to flight testing: wind-up turn" from Nasa Dryden flight research center. It's very interesting that such a dynamic and complex maneuver is used to explore an aircraft's longitudinal stability. Of angle-of-attack, airspeed, power setting, bank angle, and dive angle, note which parameters are held constant, and which are intentionally varied to drive the maneuver, and which are intentionally varied in a "responsive" manner to achieve the goal of holding other variables constant, and which are left to vary of their own accord.

(In each of the above 4 links, note the marked absence of any reference to a strong relationship between the "match" (or lack thereof) between the pilot's pitch inputs (or the G-loads) and the bank angle, and presence or absence of sideslip!)

www.djaerotech.com/dj_askjd/dj_questions/sweepback.html
www.djaerotech.com/dj_askjd/dj_questions/sweepdihedral.html
www.djaerotech.com/dj_askjd/dj_questions/fwingdihedral.html
www.djaerotech.com/dj_askjd/dj_questions/sweepwash.html
www.djaerotech.com/dj_askjd/dj_questions/sweepdihedral2.html
www.djaerotech.com/dj_askjd/dj_questions/flywingfly.html
www.djaerotech.com/dj_askjd/dj_questions/stability.html

--These pages are from a model airplane q-and-a webpage and contain some insightful comments on sweep, dihedral, anhedral, fins, yaw and roll stability, etc. In relation to the topics discussed on the Aeroexperiments website, the most interesting aspect of the above links is the attention given by the authors to explaining why the dihedral-like properties of a swept wing are highly dependent upon the angle-of-attack of the wing as a whole--the dihedral-like effects of sweep vanish at the zero-lift angle-of-attack, and become progressively stronger at progressively higher angles-of-attack and progressively higher lift coefficients. This allows us to understand why a wing with both sweep and anhedral might show a strong anhedral effect at low angles-of-attack, and a much milder anhedral effect (or a neutral effect or a mild dihedral effect) at high angles-of-attack. This was the behavior that was observed in some of the experiments with the variable-geometry Zagi and the full-scale flex-wing hang gliders as described elsewhere on the Aeroexperiments website.

A few more from D and J:

dihedralflat -- an excellent description of how a high wing configuration creates a dihedral effect (now ask yourself, is a dihedral effect created when the wing is on struts high above the fuselage, and if so, why?)

ruddervators -- I've included this one because of the reference to the primitive blind-flying aid! Also contains notes on how the "airflow curvature" effect creates a difference in airspeed between the two wingtips during a turn, and creates an inward airflow over the vertical tail during turn, and increases the angle-of-attack of the horizontal tail during a turn (which tends to pitch the nose downward, decreasing the angle-of-attack of the wing).

wizarddihedral -- does dihedral reduces the sink rate during tight circles in turbulent air? (they are a bit wide of the mark with respect to the Prairie Falcon observation...)
dihedral -- a bit more on the above topic

forwardswept --looks at how aftwards sweep contributes to yaw stability (the familiar "weathervane effect"), and then examine aeroelastic issues relating to forward-swept wings.

dutch_rolls -- yaw rotational inertia is significant

vtaileff -- interesting thoughts on V-tails and T-tails
tundediff -- more interesting notes on V-tails
tundediff -- on tail volume coefficients

flywingtheory -- 2 mechanisms for pitch stability in flying-wing aircraft
canard -- interesting notes on canards
lifttail -- interesting notes on upward-lifting tails, downward-lifting tails, hysteresis (but what if we want to reduce wing loading, i.e. what is a soaring bird doing when it fans its tail?...)

downwind -- debunking the myth of the dangerous downwind turn
wind_plane -- more on the above topic, with some interesting notes on wind shear

hanglider -- building an RC hang glider? (The glide ratios given here are about one third of what modern flex-wing hang gliders get!)

www.djaerotech.com/dj_askjd/ -- search or browse the database of questions. This is really an extremely good resource for all sorts of aerodynamics-related questions; see especially the "Design" and "Flying Techniques" categories.

"Flight Testing of Flexwings" by Dr. W. G. Brooks -- notes about flight-testing of flex-wing hang gliders and trikes. Note in particular the discussion of the purpose and consequences of anhedral in section 3--this is essentially a description of the negative coupling between yaw (sideslip) and roll that I encountered after adding a rudder to several flex-wing hang gliders as described elsewhere on the Aeroexperiments website.

Website for "The Hang Glider's Technical Notebook" from Finbar Sheehy, Ph.D. -- this is a great little book

"Thoughts on Handling Under Power" --this article by Richard Cobb entitled addresses turning and roll stability characteristics of hang gliders when flown with powered harnesses. There are some good insights here into hang glider roll stability and handling characteristics, and some interesting experimental observations, as well as some good practical and safety-related advice. Includes some great diagrams covering some of the basic principles of stability and control--see especially the diagram of the stabilizing roll torque created by sweep when a sideslipping airflow is present, and the diagrams illustrating how the descent rate or climb rate affects the difference in angle-of-attack between the inside and outside wingtips during turning flight. Includes a link to a video clip showing RC turning a flex-wing hang glider during powered flight solely by twisting the thrust line to the side, with no weight shift. Navigate from this link to "Wind drifter home" to find much more material relating to practical aspects of learning to fly powered hang gliders.

"Wrestling With the Beast: working with, instead of against, a powered harness for easier handling" (Adobe document)--this article by Richard Cobb is essentially a more polished version of the above article.

This is the video clip from Richard Cobb's "Thoughts on Handling Under Power" article, showing RC turning a flex-wing hang glider during powered flight solely by twisting the thrust line to the side, with no weight shift.

More powered harness links

"The Pod Harness Yaw Neutralizer" by Jeff Roberson. This is an interesting hang-gliding link. The author mounted a fin on the rear of his harness and reported that this makes one-handed flying much easier. This sheds some interesting light on hang glider stability and control, and would be a practical addition for people like me who are often using one or both hands to play with gadgets, to change film in flight, etc.

"The Lever Link" by Jeff Roberson. This article details the keel-shift geometry of flex-wing hang gliders and explains how a pilot's weight-shift roll inputs shift the keel to the side and redistribute the sail billow. Excellent animated figures make this geometry much easier to understand. Then the article continues with a detailed proposal for a leverage mechanism to greatly amplify the keel-shift effect resulting from the pilot's roll inputs, yielding much greater roll contol authority. A "must" read-- this idea could be the latest revolution in the design of flex-wing hang gliders.

www.ptone.com/flare/ --Animation of a hang glider landing flare. This is way too cute—push the “whack” button or the “flare” button. Accompanying link connects to Richard Cobb’s article on the physics of the hang glider landing flare, from the August 1990 Hang Gliding magazine.

Eclipse movie collection from NASA Dryden flight research center--Movies and notes on Eclipse project which involved using a C-141 to tow an F-106 Delta Dart.

More on the Eclipse project: "Eclipse Tow Launch Project: Developing an Alternative Space Launch System", "Lowering the Cost of Space Launches", "Simulations in Support of Towed Flight Demonstration".

Some basic notes on the physics of turns (sailplanes) from "Theory of Glider Flight" by Bret Willat

"Stability vs. maneuverability" by Andy Lennon from the October 1999 issue of Model Airplane News -- note the comment that an overly large vertical fin will reduce spiral stability

"Stability and Control" --(author Ray Preston?) a good chapter with some helpful animations from an on-line aerodynamics textbook (but the flying-wing section is focussed entirely on reflexed airfoils)

Some assorted pitch stability and control pages: "Pitch Stability in Indoor Models" by Steve Gardner (assumes lifting tail); "Horizontal Tail: Pitch, Stability And Control " by Chris Heintz (Zenith Aircraft designer presents rules of thumb); "Passive pitch stabilization" from the "Actively Stabilized Flying Wing Plank Project" by Helmut Lelke (lots of food for thought here, the brief description of the two usual methods for stabilizing a flying-wing aircraft are of special interest); "Theory of the forward Swept Flying Wing" notes from Bill Daniels re Marske Pioneer etc

"The Origins of the First Powered, Man-carrying Airplane" by F. E. C. Culick -- an interesting, concise look at the accomplishments of the Wrights and their predecessors from an engineering viewpoint, with notes on the evolution of the understanding of stability and control issues

"Airplane Stability and Control, Second Edition: a history of the technologies that made aviation possible" by Malcolm J. Abzug and E. Eugene Larrabee. (Adobe document, sample containing only index and most of chapter 1.) -- Fascinating.

Stanford Java Wing Analysis Program -- allows you to enter aspect ratio, sweep, taper, and twist, and provides the Cl curve and lift distribution curve.

www.lilienthal-museum.de/olma/ehome.htm -- all about the man who started it all...

www.rocketguy.com --and here is a pioneer for modern times...?? (Now eclipsed by Scaled Composite's SpaceShipOne...)

Boost Glider model rocket FAQ --note the references to trimming for spiral stability, Rogallo ("flexie") wings, thermalling, and more. Truncate the url to the basic "...dot org" for more interesing stuff.

www.gizmag.com/go/3060/ target="_blank" --this is a fascinating link to 50 different innovative projects at the cutting edge of aviation and aerospace, including this alternating negative/positive buoyancy glider.

members.shaw.ca/sonde/index.htm target="_blank" --a Canadian team's effort to drop a small semi-autonomous unpiloted glider from a balloon at very high altitudes (up to 80,000 feet.) The highest altitude achieved was 60,000 feet before the glider was lost in September 2003.

CyberBug UAV hang glider (note resemblance to one of the test vehicles used in the experiments described on this website!)

Winged suit flyers:

Soul flyer 1-- bird man jumps from helicopter with winged suit, rockets down a steep mountain slope, a few meters off the ground, at a terrific speed, then opens parachute.

Skydivers with miniature wings:

Jetman 1-- bird man jumps from Pilatus Porter airplane wearing a folding rigid wing with miniature jet engines, flies low over snowy mountains, climbs to fly in formation with jump aircraft, lands under canopy.

Home made hang glider in India -- (video clip--click on the link in the lower left corner of the home page)

http://media.animal.discovery.com/convergence/spyonthewild/birdtech/birdtech.html -- Bird cam: Golden Eagle on the wing

www.angelodarrigo.com -- Fascinating interdisciplinary raptor migration / hang gliding project, also a project to fly a hang glider over Mount Everest, and much more.

More on the Mt. Everest hang glider project, including notes on releasing a Golden Eagle back into the Himalayan wilderness

www.nepal-paragliding.com/parahawking.htm -- Amazing project that offers the opportunity to paraglide in Nepal with an incredible menagerie of wild raptors, and trained falcons that locate thermals

www.operationmigration.org -- Endangered species re-introduction project: using ultralight aircraft to teach captive-born Whooping cranes to migrate

Tactics and Vectors -- A site dedicated to promoting field studies on flight tactics and navigation of migrating butterflies in North America. See especially the sections on navigation with respect to the sun, earth's magnetic field, etc., and on soaring flight strategies, and on using soaring aircraft and ultralight aircraft to learn more about these winged creatures.

users.lazerlink.net/~pagenbks/ -- Dennis Pagen's books are outstanding references for any hang glider pilot, paraglider pilot, or ultralight pilot. "Understanding the sky" (1992) offers a detailed examination of soaring weather, in a way that is accessible to the general reader, and should be of great interest to anyone interested in soaring flight on any scale --I recommend this one to my ornithologist/ hawk watcher friends as well as to pilots. "Hang Gliding Training Manual" (1995) and "Performance Flying" (1993) are essential texts for the new or advancing hang glider pilot and excellent refresher books for experienced pilots. The new "Secrets of Champions" is full of cross-country and competition tips from a broad selection of top pilots on thermal finding and centering techniques, overall strategies, psychology, and much more.

United States Hang Gliding Association "Articles" page -- Includes some interesting meteorology (thermals) articles and safety articles. See also the comprehensive "Links" page. PS if you are new to the world of modern hang gliding, navigate to the "Where to learn" section.

Wills Wing "Articles" page -- These articles contain some interesting technical information on hang glider aerodynamics, as well as a wealth of practical information

Moyes "Articles" pages -- These pages contain hundreds of interesting hang gliding articles. Mostly non-technical but some delve into a detailed look at the design, construction, and flight characteristics of modern high-performance hang gliders. Note the navigation buttons in the upper left corner of the page. A few selected highlights: A day in the lift of a Moyes test pilot, Winter flying in Austria, Winter soaring at Mt. Cook, Mexican balloon drop, Tumble at the Worlds, The longest hang gliding flight (437 miles!), UV meter, Moyes Litesport--a Cinderella story (note the interesting technical details including the way that the lower side wires are kept tight when the VG is applied), Litespeed 5 release (includes cool test rig photos), Litespeed 3 review (includes some interesting notes on scaling effects), Moyes Litespeed--a new era of lite (note the comment on sideslip in comparison with the CSX), The making of a topless glider--Moyes CSX (includes interesting technical notes from the pioneering days of topless gliders), Moyes CSX--borne and bred to race (includes many interesting notes on topless construction and pitch stability; the comments on sideslip are particularly relevant to the ideas discussed on the Aeroexperiments website).

Link to comprehensive Litespeed tuning article and matrix -- This link is highly relevant to the ideas discussed on the Aeroexperiments website, because a comprehensive theory of the balance of roll torques on a circling hang glider, including the true aerodynamic effects of anhedral and the dependence of these effects on a sideways (slipping) component in the airflow, should mesh with the real-world observations given in this article.

A random assortment of hang-glider flight reviews:Lightspeed review from Doc at Dynamic flight-- note the comment about curved-tip gliders being "skatey" on tow (I've also heard the opposite), and the recommendation to tow with VG full loose, and the comment about this glider showing less tendency to sideslip, when the pilot rolls into a bank and then pulls in the bar, than the Moyes CSX. Flight test report on WillS Wing Eagle from December 2000 issue of Skywings-- note the suggestion that the glider is more spirally stable, as well as more stable in yaw, when the fixed vertical fin is installed

Basic notes on hang glider "washout struts" from an on-line encyclopedia; includes notes on effect of washout on spiral stability

"How a flex wing turns" -- includes a good illustration of billow-shift

A random assortment of links relating to hang glider performance, stability, and control: New Trends and Developments in Hang Gliders (abstract and first page only) from Glen J. Brown, 1974!

A random assortment of links relating to tuning indoor and outdoor free-flight model airplanes, which provide some interesting food for thought in relation to stability and control: FSEA student handout, collection of articles on indoor duration models

A random assortment of on-line threads relating to handling and other aspects of RC model airplanes, including notes on the way that an over-large vertical tail can decrease the roll stability of a model with dihedral: discussion of electric Cub from "RC universe", discussion of forward-swept wings from "RC groups"

Flight manuals for some interesting aircraft: Bailey-Moyes Dragonfly (Adobe document)

Flight reviews and test flight reports for some interesting aircraft: Dave Broyle's review of the SuperFloater ultralight sailplane-- see especially the comments on yaw strings and sideslips. Dave Welles flight report on the Marske Pioneer 2D flying wing sailplane--some interesting food for thought here in relation to the dynamics of flying-wing aircraft.

Links to notes (manufacturer's web pages etc) on some more interesting aircraft: Greg Cole's SparrowHawk and DuckHawk sailplanes (produced in Bend, Oregon), Aeriane Swift ultralight sailplane, Aeros AL-12 ultralight sailplane, Aeros Stalker rigid-wing hang glider, Seagull Aerosports Escape Pod (streamlined trike), Hidden Mountain Flight (high-performance powered harness for hang gliders)

In praise of "armchair" flying: "Third Wave" by Mike Sandlin, describing the "Goat" and other similar ultralight sailplanes that can be wheel-launched from hang glider launch sites. (More on the "Goat" and other basic ultralight gliders.)

Mike Sandlin's experimental rigid-wing hang gliders

Mike Sandlin's drogue chute page (covers both commercially-available and home-made drogue chutes).

Notes on Mike Kollman's "Raptor" rigid-wing hang glider: from the Delta Club 82's "Hang Glider's Bible"

Some hang glider manufacturers: Wills Wing, Northwing, Seedwings (Sensors), Finsterwalder/ Charly, Moyes, Airborne, Aeros, Icaro (Laminar),

Hang glider directories (these are currently rather sparse in their coverage of newer gliders): "Hang Glider Bible" from Delta Club 82. Check out the "chronology". Hang glider data base from Topa flyers.

Hang glider classified ads: USAirnet link to 15 ad sites, CloudBase Country Club (WA), Oregon Hang Gliding Association, ValleyVille Hang Gliding Association (OR)

Flying-Related Links and General Information from Peter Birren--this is probably the best hang gliding-related "links" page in existence, with links to many interesting and useful articles by Peter Birren--including much information on ground-based towing--and other links to hundreds of other useful sites.

USAirnet hang gliding links--this is another great resource, with links to hundreds of useful sites.

Hang Gliding and Paragliding Association of Canada fatality reports 1974-2003 -- Cautionary tales: see how far we've come. Many notes from the bad old days. Illustrates why you shouldn't teach yourself to hang glide, or entrust your life to a decades-old wing from somebody's garage. Note the high proportion of accidents involving primitive towing methods, and beginners flying unsupervised in advanced conditions, and luffing or unstable gliders. Navigation to hang gliding/ paragliding safety comparison stats. Navigation to the rest of the HPAC website.

More information on foot-launched flight: "Don't try this at home (except after proper instruction)!" -- prospective new hang glider and paraglider pilots should read and heed this article by Peter Gray. Also includes links to reports on recent competitions, by Peter Gray. Also check out the "Strange Brew" cartoon on the same page, it pretty much says it all re "wuffo" attitudes toward flight!

Thermal physics and superstitions -- links to an interesting set of articles by Peter Gray exploring whether thermals can really be "triggered" by small mechanical disturbances, and other similar questions.

The Reel Hang Glider Pilots Association--On Lockouts --this superb page on the RHGPA website is full of practical advice and also offers some well-reasoned analyses on the physics of the lockout phenomenon. Oriented toward ground-based towing. Includes navigation to the rest of the Reel Hang Glider Pilots Association website, and many other interesting links.

"Nordic Static-Line Towing"--notes on auto towing hang gliders with a fixed-length rope. Video clip

Excellent hang-glider aerotowing tips from Quest Air. (Note-- I do disagree with some of the tips given on this site under the heading "Handling the glider (avoiding oscillations)". Most pilots have found that it is not helpful to "lead with the legs" while flying a hang glider on tow. Likewise, most pilots have found that it is not helpful to try to keep their body parallel with the keel while making roll corrections on tow. "Leading with the feet", or keeping the body parallel to the keel, both require that the pilot exert some amount of "shopping-cart"-style twist on the control bar to counteract the towline's pull. Most pilots find that it while flying a hang glider on tow, it works better to exert a purely sideways force on the control bar, without exerting any "shopping-cart twist" on the bar. Due to the geometry of the towline's pull, exerting a purely sideways force on the control bar will cause the pilot to "lead with the shoulders", while the legs and feet will remain relatively stationary. In free flight, this is undesireable ("cross-controlling"), but on tow, most pilots have found that this style of flying works very well and helps prevent the glider from entering into yaw-roll oscillations. The author of this tips given in this link suggests the opposite.)

Excellent hang-glider aerotowing tips from Cowboy Up Hang Gliding

Here is an interesting aerotow cart design, plus a tool to find the surface wind direction, from an Ontario pilot. Read and heed the cautions against adjusting any aerotow cart so that the glider's keel rides too high!

"Lockouts"-- some excellent reading from the "Dynamic Flight" school in Australia. Read and the heed the warning against relying on a weak link to protect you from a lockout! See also the detailed information specific to ground-based towing.

the Oz Report newsletter (hang gliding)

the Oz Report discussion forum (hang gliding)

"HangGliding.org" discussion forums

www.landings.com hang gliding/paragliding page --hundreds of hang gliding links, and navigation to thousands of other aviation links.

Basic information about hang gliding:

How Hang Gliding Works-- from the "How stuff works" website

Hang gliding FAQ from DFSC in Michigan-- a good FAQ page for those unfamiliar with this unique way of flying

 

 

Where to learn hang gliding:

United States Hang Gliding Association index pages for finding instructors, schools, and clubs near you.

Wallaby Ranch (FL), Quest Air (FL) -- two of the premier flight parks for aero-tow-based hang gliding and aero-tow-based hang gliding instruction

Windsports --expert hang gliding instruction based at Dockweiler beach and nearby mountain sites, in the Los Angeles area.

San Francisco Hang Gliding Center --expert hang gliding instruction in the Bay area

Hang Glide Utah -- based around the famous "Point of the Mountain" site.

Learn to hang glide in Oklahoma --Jim Reynolds is a master instructor who has recently relocated from the Pacific Northwest

Hang gliding via aerotow in Kansas

Cowboy Up Hang Gliding --Hang gliding via aerotow, truck tow, and foot launch in Wyoming, offered by master instructors.

www.oregonhanggliding.com --John Matyonek's web page. John is one of those hard-to-find people--a dedicated, active, hang gliding instructor. John is based in Corvallis, Oregon. If you need to purchase gear, John can ship equipment anywhere. (John is a dealer for Wills Wing, Brauniger, Flytec, and many other manufacturers).

Cloudbase Ultralights --A source of "trike" instruction in Oregon's Willamette Valley.

Paraventures -- Brad Hill and Maren Ludwig offer expert paragliding instruction based in northwest Oregon. Includes good "weather" links.

 

 

Some hang gliding clubs and site guides:

ValleyVille Hang Gliding Association, Peterson Butte site guide -- my local hang gliding club that focusses on the central and southern Willamette Valley (Oregon) (member ohtofly)

Oregon Hang Gliding Association -- a Portland-based hang gliding club that covers all of northwest Oregon (ohga newberg)

Cloud Base Country Club, site guide -- a Washington hang gliding club

Rogue Valley (southern OR) Hang Gliding and Paragliding Association, Woodrat Mountain site guide, Starthistle fly-in (around Memorial Day)

Cascade Paragliding Club, site guide, (site map) -- includes good "weather" and "flying site map" pages for Oregon.

Desert Air Riders paragliding club, site guide, Pine Mountain fly-in (around Labor Day) -- includes good weather and site information for sites near Bend OR including Pine Mountain, Mt. Bachelor, etc. Hang glider pilots will also find some of the information here to be useful.

Hat Creek Rim info from Shasta Sky Sailors. There is often a fly-in around Labor Day.

Chelan Flyers, site guide, events including the Chelan Classic around July 4

Calendar for Lakeview Festival of Free Flight information and site guides. The meet is held around July 4 each year in Lakeview, Oregon.

King Mountain Hang Gliding Championships website, site guide. The meet is held each year in mid-July.

 

 

Some hang gliding video clips:

D's ride to cloud base, WA 2005

DG's morning wave flight at the Gulf of Carpentaria, Australia, September 2005

Flex-wings, rigid-wings, and Swifts aerotowing at Big Springs TX, August 2005

Hang gliding gone wrong-- mishap compilation from you-tube

 

 

Some hang gliding video clips that show how flexible wings change shape in flight:

Airborne glider looping-- note how the outboard trailing edge flexes up, then drops back down

 

 

Some more hang-gliding-related "how to" links:

Joe Greblo on No Flare Landings

Building a Helmet Headset & PTT for a Yaesu/Vertex VX-150/170 2M Handheld Transceiver

"Go Pro Hero" miniature video camera website-- this is a great camera for mounting to a hang glider or even an RC model. The "Helmet Hero Wide" package comes with a good collection of mount accessories suitable for creating a mount for use in hang gliding or RC modeling. A high-definition version is coming out soon.

 

 

Basic information about soaring in sailplanes:

Introduction to Soaring-- this is a beautiful little series of photos and text

How Gliders Work-- from the "How stuff works" website. See especially the explanation of how ballast works, and the picture of the yaw string, on this page)

Soaring Society of America (sailplanes) -- many interesting links here

"Where to fly sailplanes in the US": SSA's interactive map of clubs and commercial operations

A directory of US soaring (sailplane) clubs and commercial operations -- also navigation to other soaring (sailplane) related links

Another directory of US soaring (sailplane) clubs and commercial operations

Northwest Sky Sports-- Gary Bogg's commercial sailplane operation, operating from Hood River, Sunriver, and other Oregon locations. Among other things, Gary is an expert mountain wave pilot.

Willamette Valley Soaring Club (sailplanes)-- operating primarily from North Plains in the spring/ summer/ fall, and from Hood River (for wave flying) in the late fall/ winter/ early spring.

High Desert Soaring Club (sailplanes)-- based in Bend, Oregon

Coburg Hills Sailplane Club (sailplanes)-- operating just north of Eugene Oregon

 

 

Links page of the vintage ultralight and lightplane association--a very interesting collection of aviation-related links including hang gliding and sailplane links.

Pilotfriend's sailplane and soaring links--an interesting collection of sailplane/soaring links.

Soaring tips and ideas from Peter Kelly--an interesting collection of sailplane/soaring aricles, including some good articles on soaring weather

Pretty pics: Northrop N-9MB #1, #2, #3, #4, #5

 

 

www.whittsflying.com --This site contains a vast array of real-world, experience-based information about the practical aspects of flying conventional airplanes in the modern environment. Not so much about aerodynamics and physics, or about gliders or flying wings, but we include it here because it is so comprehensive.

FAA regs: Airspace classes and cloud clearance requirements, Part 103 (Ultralight vehicles) regulations and commentary

 

 

www.radiocarbonart.com -- Paul Naton produces spectacular videos, most of which feature aerial footage shot from radio-controlled model sailplanes. "Just Want to Fly" includes a fascinating description of dynamic soaring (which is conducted in the rotor behind the hill top, where there is no lift) and "Secrets of Thermal Soaring" provides some detailed, practical lessons on thermal formation, including the smaller-scale phenomena that full-scale pilots aren't aware of.

www.shredair.com -- Quality RC sailplanes and other gear from Dieter Mahlein and Marcela Leal

Portland Area Soaring Society (RC sailplanes)

Links to 5 other OR/ WA RC soaring clubs and many other RC-soaring-related links from the PASS website

"What do thermals look like" by Wayne M. Angevine, from the PASS website

"An Addendum to the Old Buzzard's Soaring Rules"by Jay Decker, from the PASS website

Seattle Area Soaring Society (RC sailplanes)

RC soaring information from SASS -- includes a site guide and much more

RC soaring technical information from SASS -- includes airfoil and design information and much more

RC soaring technical information from SASS -- includes airfoil and design information and much more

"Trimming and setup of a glider with a 4 servo wing" by Erik Dahl Christensen--includes notes on butterfly (crow) mixing, V-tail mixing, differential ailerons, flaps coupled to ailerons, rudder coupled to ailerons to counteract adverse yaw, camber adjustments for thermalling and cruising, snap flaps, CG location and pitch stability testing, and more. Also includes navigation to many other interesting technical articles on RC sailplanes by the same author, and navigation to many other related websites.

rc-soar.com/links/index.htm -- a vast number of RC-soaring-related links

www.rcgroups.com -- RC soaring discussion groups, including areas for "slope", "thermal", "dynamic soaring", and more. (Scroll down past the "airplane" section).

Good advice for beginning RC glider pilots: Leonard Barton's RC sailplane page, Fatlion's RC sailplane page

Check out the TG-3 on this DAW website. It looks like a great trainer RC sailplane that should be both durable and user-friendly. I have a soft spot for TG-3's as I learned to fly full-scale sailplanes in one. Check out giant scale Ka-6 as well!

Some other websites of RC glider manufacturers: Micheal Richter Designs (www.dream-flight.com), Leading Edge Gliders, North County Flying Machines, Combat Wings, Trick RC (Zagi)

RC sailplane ideal CG calculator from silentflight.net.

Some RC video clips (see also the RC dynamic soaring video clips listed near the top of this page)

Excerpts from "Just Want to Fly"

Excerpts from "Just Want to Fly 2"

Excerpts from "Lift Ticket"

Excerpts from "Lift Ticket to Norway"

 

 

Some interesting content from on-line discussion groups--thoughts on the relationship between control stick position and angle-of-attack from the Aeroplanner website (I'm "hangglider" in this conversation and I describe some interesting experiments which will be eventually posted on the Aeroexperiments website).

Are you thinking "outside of the envelope"?--Escaping the planet...

Click here for an additional page of randomly assorted aerodynamics-related links

 

 

Some compass-related links and GPS-related links:

Bohli compass links: Manual for Bohli compass (Adobe document), company home page -- This remarkable non-gyro non-electronic device is free from the errors that affect a standard magnetic compass, and provides 3-dimensional attitude information to an aircraft in cloud.

Explanation of northerly turning error -- this is why a southerly magnetic heading is your only hope (in the northern hemisphere) if you are whited out with only a standard magnetic compass.

Using the GPS as a safety tool -- by Peter Gray

David Wheeler's hints on using a GPS for soaring competions

Tiger Mountain area waypoints (for "Tiger Tag"), plus relevant portions of Seattle class B airspace downloadable to Garmin GPS, plus freeware for uploading these items to Garmin GPS and downloading tracks from Garmin GPS -- created by David Wheeler

Soaring software links: using PDA's as soaring flight computers, displaying GPS and barograph data after a flight, etc:

Soaring Flight Software Comparison from Cumulus Soaring, Inc. -- a great resource for comparing products intended to be used on PDA's during soaring flight. Includes many links to related topics.

"See You" -- software for creating a 3-D depiction and analysis of your soaring flight from vario and GPS data

"See You mobile" -- moving map, navigation, and soaring computer software for use in flight on a pocket PC

Dr. Joe Jordan's Skypower website -- Focuses on renewable energy. (We are digging ourselves into a deep hole by relying on the "black energy" of fossilized sunlight, while our earth is being continually bathed in enough new sunlight to vastly exceed our energy needs). If you ever get the chance to hear Dr. Jordan speak on renewable energy, astronomy, or atmospheric optics (mirages, glories, etc), don't miss it.

From the Astronomical Applications Department of the US Naval Observatory: sunrise, sunset, moonrise, moonset, civil/astronomical/nautical twilight, solar/lunar eclipse calculators for any date, any location. This link includes a calculator that allows the user to input his elevation above sea level, and produces the time and the azimuth of rising and setting of the sun, moon, and other major bodies--this is extremely valuable for planning certain kinds of artistic aerial or mountaintop photography shots. Earth's seasons: Equinoxes, Solstices, Perihelia, and Aphelia 1992-2020. Links to much more.

Current moon phase

"Solar System Live" by John Walker -- this model generates views of the solar system showing the position of the various planets and other bodies. See also John Walker's "Home Planet", a public domain earth/space/sky simulator.

Calendars of meteor showers and other astronomical events: Brief summary of major meteor showers (2007, 2008), "Meteor Showers Online" by Gary W. Kronk, IMO comprehensive calendar of meteor showers (2007, 2008)

Auroral forecasts from the University of Alaska at Fairbanks, with links to custom maps of the aurora centered on your location, and information on signing up for email auroral alerts.

Math and conversion links: trigonometry calculator, conversion calculator, other useful scientific and mathematic calculators, still more on-line calculators

Simple calendar (with holidays and approximate moon phases)

Video of "gravity wave" in atmosphere at Tama, Iowa, with explanation, from Live Leak

Photo of spectacular mammatus clouds over Hastings, Nebraska

Amazing photo gallery of birds in flight by Herbert Knufken

WEATHER LINKS -- The remainder of the links on this page are sites I use to check the local (Oregon) weather for hang gliding etc, followed by some weather tutorials, followed by some weather cams from Oregon and elsewhere.

Click here to skip down to the weather cameras.

Click here to skip down to some tutorials on soaring weather, or click here to skip down to some tutorials on using the MM5 sounding diagrams.

A few introductory notes on the weather links:

There are many different weather products listed here! Only a few need be used at any given time.

For many of these products, it's helpful to bear in mind that Pacific Daylight Time is 7 hours earlier than UTC (also called GMT or Zulu time), and Pacific Standard Time is 8 hours earlier than UTC. In many cases (near midnight) this can cause a difference in dates.

* Click here to see my favorite links to check when considering flying at Peterson Butte, near Lebanon Oregon. (All these links also appear in the main list of weather links below.)

* Click here to see my favorite links to check when considering flying at the north or central Oregon coast. (All these links also appear in the main list of weather links below.)

* Click here to see my favorite links to check when considering a wave attempt at Hood River.

MM5 "Soundings": NAM 12 km*, GFS 12 km*, extended GFS 12 km.

* NOAA NWS forecast discussions from the Portland, Seattle, Medford, Pendleton, Boise, and Spokane offices. This is a very interesting resource that often gives commentary on the various versions of the MM5 weather model, along with a great deal of additional information. (Each of these links appears one more time further down on this page.)

Soaring forecasts (the "height of the minus 3 index" is a good indicator of how high a glider will likely be able to climb in thermal convection over flat ground):

Notes on how to get soaring forecasts for Salem and Medford by phone: dial "1-800-wx-brief", and when the recording starts, enter "221". Or dial 1-800-wx-brief and ask a human weather briefer to read you the Salem and Medford soaring forecast. (Note April 2007: due to budget cuts and contracting-out of FSS services, these items are no longer available by phone.)

* NOAA soaring forecasts for Salem and Medford today (this is the best link for Salem and Medford and is based on actual balloon soundings; the other links below are based on a computer model and seem to be more experimental), second link for Salem today, Salem tomorrow, second link for Medford today, Redmond today, Redmond tomorrow, navigation to soaring forecasts for Washington, ID, and MT locations, plus sounding charts

Upper air soundings for various spots in the US from topaflyers.

Home page for DrJack's soaring forecasts -- thermal forecasts and other soaring forecasts from Dr. John W. (Jack) Glendening

DrJack's NAM blipmaps for the Pacific Northwest

DrJack's RUC blipmaps for the Pacific Northwest

For some of the sounding generators listed below, it is useful to know the coordinates of various flying sites. Here is a link that provides the coordinates of some Oregon hang gliding sites.

MM5 weather model: (MM5 home page):

Brief notes on the MM5 model: MM5 forecasts are initiated at 0000 and 1200 UTC, which is 5AM and 5PM PDT or 4AM and 4PM PST. The first frames of the runs become available several hours after this time (around 9AM/PM PDT or 8 AM/PM PST) and it takes at least an hour longer for the entire run to be completed.

The GFS version is generally the best, especially for longer-range forecasts, but the NAM version is often more useful because the latest run of the NAM model is available about an hour earlier each morning or evening than the latest run of the GFS model. Check the initiation time of the run you are looking at and see if the NAM version is fresher. All the models cover a 72-hour time span when they are finished running.

Be aware that comparing the GFS model with the NAM model is a bit like comparing apples with oranges. For example, imagine that you checked the weather late in the evening when both the GFS and NAM models were available, and you chose to look only at the GFS model. Now you are checking the weather again in the mid-morning, and only NAM model is available. If you see something in the model that looks very different from what you saw the previous evening, before you assume that a real change in the meteorological conditions has caused a significant change in the forecasts, it's worth taking a look at the previous evening's run of the NAM model. Often there is more consistency between consecutive runs of a given model (e.g. the 5AM and 5PM runs of the NAM model) than there is between simultaneous runs of different models (e.g. the 5PM run of the GFS model and the 5PM run of the NAM model).

Favorite MM5 links:

Oregon. winds and 1 hr precip: NAM*, GFS*, (extended GFS), GFS 4 km scale.

Oregon and Washington together, winds and 1 hr precip: NAM, GFS, (extended GFS), GFS 4 km scale

12 km full view (extends into southern British Columbia and northern California) winds and 3 hr precip--extended GFS

12 km full view (extends into southern British Columbia and northern California) sea level pressure, 10m winds, 925 mb temps--NAM, GFS, extended GFS

"Soundings": NAM 12 km*, GFS 12 km*, extended GFS 12 km.

Click here to see a larger collection of MM5 links.

"Weather forecasting using the MM5 website" by Steve Roti--lots of good information here, especially on how to read the "soundings" graphs.

"How to find and read an MM5 sounding chart" by Matt Amend--a superb step-by-step tutorial.

"Soundings"--this tutorial is from the MM5 website

"Soundings in depth"--a more detailed tutorial from the MM5 website

Some more links to tutorials on soundings are given in the list of weather tutorial links near the bottom of this page.

NOAA GSD Rapid Update Cycle home page

NOAA GSD Rapid Update Cycle "13 km oper RUC" model, northwest US region, surface wind field, all times

* The Rapid Update Cycle model is updated much more often than many other weather models, such as the MM5 GFS and NAM models

* I'm not familiar with the pros and cons of the various scales and versions of the RUC models-- experiment and see what seems to work best for you

NOAA GSD Rapid Update Cycle soundings (skew-t log-p diagrams)

Some notes on using the above Rapid Update Cycle soundings link: (Click here to skip past these notes)

* This is a great resource!

* Scroll down & click the button called "Bak20 (Backup 13km RUC on 20km grid)".

* Then select the number of hours out that you want the forecast. (E.g. "12" if you are checking on the morning of the day of interest.)

* Then enter the site designation or coordinates. (Some Oregon designations: Salem is SLE, Medford is MFR, Redmond is RDM).

* Then click on Java-based plots.

* After a little while it loads all the soundings at 1-hr. intervals. Click on the hour of interest: for PST, 0000Z is 1700 hrs (5PM).

* The chart is interactive, so you can zoom in by clicking & dragging to outline the part of the chart you want to zoom in on.

* Move your mouse up & down the temp line (red) to see a readout of wind direction, speed, temp., pressure, etc.

* Click on the ground-level elevation at the expected surface temperature for that hour. This will project a pink line. This pink line represents the temperature experienced by a unit of air rising from the ground without mixing with the surrounding air. At some point there will be a black line, and a change in angle of the pink line. This represents the point where a cumulus cloud will begin to form, so that the cooling rate of the thermal changes from dry adiabatic to wet adiabatic. The thermal should continue through all altitudes where the pink line remains to the right of the red line. When the pink line meets the red line, the thermal will stop rising.

Instructions for using the interactive parcel trajectories on the RUC soundings chart from the RUC soundings web page

Some more links to tutorials on soundings are given beneath the MM5 links a bit further up this page, and in the list of weather tutorial links near the bottom of this page.

Links for longer-range forecasting: our local weather guru says: "For those who are somewhat comfortable with model output and peering into the future based on the jet, the surface pressure systems, and the 500 mbar surfaces, the following two parent sites have absolutely fantastic graphical model results available so you can peer a bit further into the 'future' of large structures in the atmosphere:
http://wxmaps.org/
http://weather.unisys.com/ "

"Where to fly"-- Jimmy B's weather forecasting program for foot-launched flying sites in the Pacific Northwest

Cascade Paragliding Club weather links page

Cascade Paragliding Club interactive map of Oregon and Washington with weather forecasts, MM5 soundings, weather observations, and site guides -- this is a great link. It is especially useful for sites like Pine Mountain that are remote from the established "sounding" locations for the MM5 model (but be careful not to click on the nearby Pine Ridge site by mistake!)

Intellicast wind forecast centered on Salem OR*--this link is especially useful for coastal wind forecasting

NOAA map of NW Oregon with current winds in graphic form--subtract 1 hour from the time on the map to convert to Pacific time. This link includes many coastal (and other) wind stations that are absent from the other links given below. There is also supposed to be a time-series function but it doesn 't seem to work at present.

NOAA current hourly observations for Oregon

NOAA buoy reports and coastal wind stations for the Oregon coast. (Check the time of observations as these links sometimes go for a while without updating; fresher data for the airport stations (Astoria and North Bend) is often available on the "NOAA current hourly observations for Oregon" link or the "NOAA map of NW Oregon with current winds" link (see above).)

Selected NOAA buoy reports for the Oregon coast (many more are available on the above link):
Washington buoy (approx 200 miles offshore from Tillamook OR)
Tillamook buoy (approx 100 miles offshore from Tillamook OR)
Columbia River Bar buoy
Stonewall Banks buoy (20 nm W of Newport)
Port Orford buoy (16 nm W of Port Orford)
Selected coastal wind stations for the Oregon coast (many more are available on the above link)
Garibaldi
Lincoln City
Cape Foulweather
Newport jetty
Siuslaw jetty (Florence)
For more coastal wind reports, see the "Oregon weather cams" section near the bottom of this page.

Interactive map including Oregon near-shore and far-offshore buoys from "iwindsurf.com"-- this is a great resource for checking coastal winds. Click on the individual stations for a graph comparing the forecast to the actual conditions. Note: the "Washington" buoy is misplaced on this map, it is actually far offshore to the west of the Tillamook buoy.

iwindsurf.com

Nation-wide interactive map including near-shore and far-offshore buoys from "windonthewater.com"

Satellite loops centered on Pacific Northwest USA:
(Notes--to refresh these images, use the "refresh" button near the speed controls. The "still" image is sometimes slightly fresher than the last image in the current "loop" display.)
Visible--1km--2km--4km
Infrared--2km--4km
Water vapor--2km--4km
Fog--2km
Satellite loops cover a 5 1/2 hour span--subtract 7 (or 8) hours to convert from UTC to Pacific Daylight (or Standard) time.
Navigation to other satellite images for the western U.S.

Intellicast radar loop display for western OR with "forecast" option

NOAA Radar images centered on Pacific Northwest USA:
Northwest Oregon
loop version of Northwest Oregon (slow to load)
Southwest Oregon
loop version of Southwest Oregon (slow to load)
Northwest US

NOAA forecast discussion (Portland OR office)*
NOAA forecast, Portland OR
NOAA forecast, vicinity of Lenhart airport
NOAA forecast, Central Willamette Valley
NOAA forecast, Northern Oregon Coast*
NOAA forecast, Central Oregon Coast
NOAA coastal marine forecast for off the Northern Oregon Coast--good for longer-term wind forecasts
NOAA coastal marine forecast for off the Central Oregon Coast--good for longer-term wind forecasts
NOAA forecast for Hood River
NOAA forecast for Cliffside area

NOAA --Western Oregon additional information--satellite imagery and more. Navigation to other geographical regions.

Today's NWS soaring forecast for Salem Oregon (based on a balloon sounding), second soaring forecast for Salem today (based on a computer model), soaring forecast for Salem tomorrow (based on a computer model)

HMSC tide tables*

Graphs of predicted tides for Oregon stations from NOAA/NOS

METARs (weather reports from airports) for OR and WA--particularly useful for checking ceilings on the Oregon coast (AST, ONP, OTH)

Selected METARS for the Oregon coast (many more are available on the above link):
Astoria airport (AST)
Newport airport (ONP)

Terminal Area Forecasts and Transcribed Weather Entroute Broadcasts for OR and WA--the "Terminal Area Forecast" (TAF) links are particularly useful, as they include recent observations (Metar's) as well as detailed forecasts. Again, particularly useful for checking ceilings (current and forecast) on the Oregon coast (AST, ONP, OTH). SOARING FORECASTS may also be accessed from this page.

Selected TAFS for the Oregon coast (many more are available on the above link):
Astoria airport (AST)
Newport airport (ONP)

TAF and METAR decoding guides: #1, #2

www.duat.com--synopses, METAR's, and TAF's, and more; similar to the above links but delivered in plain English as well as abbreviated code. Again, especially useful for checking altitude and coverage of current and forecast clouds. Unfortunately you'll need a pilot's license number to access this link.

Aviation overlook from NOAA from Portland OR office with easy access to latest radar picture, and visual, infrared, and water vapor satellite images, and statewide hourly weather reports, and recent Surface Analysis charts for the Pacific Northwest. (Check the dates of the SA charts carefully--times that lie in the future or very recent past actually link to yesterday's charts; new charts usually are not available until at least an hour after the time that they depict.)

NOAA NWS AWC Forecast winds and temperatures from surface to 42,000' (for entire U.S.)

Infrared satellite image centered on northwest Pacific ocean with illustrated fronts*

Intellicast surface analysis chart for entire U.S.*

Still more weather links:

NOAA forecast discussion (Seattle WA office) --includes Dog Mountain area.
NOAA forecast, Dog Mountain vicinity (Morton)
NOAA forecast, Dog Mountain vicinity (WA Central Cascades west slopes and passes)
NOAA forecast, Dog Mountain vicinity (South WA Cascades range)
NOAA forecast, Dog Mountain vicinity (Foothills of the South WA Cascades)

NOAA forecast discussion (Medford OR office) --includes Woodrat mountain area and Lakeview area.
NOAA forecast for Woodrat vicinity (Medford OR)
Soaring forecast for Salem and Medford OR (based on balloon soundings), second link for Medford today (based on a computer model)

NOAA forecast for Lakeview OR

NOAA forecast discussion (Pendleton OR office)-- includes Pine mountain area and Mt. Howard area.
NOAA forecast for Pine Mountain vicinity (Central Oregon)
Today's soaring forecast for Redmond Oregon (based on a computer model)
Tomorrow's soaring forecast for Redmond Oregon (based on a computer model)
Interpolated MM5 sounding for Pine Mountain from the Cascade Paragliding Club interactive map of Oregon and Washington

NOAA forecast for Joesph OR

NOAA NWS forecast discussion (Boise office) --includes Alvord desert area.
NOAA forecast for Alvord desert

NOAA NWS forecast discussion (Spokane WA office) --includes Chelan area.
NOAA forecast for Chelan WA

NOAA NWS forecast discussion for Sacramento CA --includes Hat Creek Rim area.
NOAA forecast for Hat Creek Rim area (Burney CA)

And still more weather links:

Hourly Accuweather.com forecast--type in your location of interest (for example "Tillamook, OR") in the upper left, press "go", then press "hourly" on the bar below

Weather Underground point forecast-- includes current winds, a 7-day forecast, moon data, day-length data, and notes on civil/ nautical/ astronomical twilights

USAir net surface weather forecasting page-- optimized for sport aviation including hang gliding and paragliding

Cascade Paragliding Club weather links page--includes links to winds aloft forecasts, jet stream analyses, soaring forecast (thermal index) generators, and more.

Oregonhanggliding.com weather links page--Many useful links here.

www.met.utah.edu/droman/states/OR_state_frame.html-- weather observations for a vast number points in Oregon (and navigation to same for other states)

www.met.utah.edu/mesowest-- home page for above link

Water vapor image centered on northwest Pacific ocean

NOAA "Satellite imagery" home page for western US--links to satellite views including visible, infrared, water vapor, fog, convective available potential, cloud top pressure, lifted index, and precipitable water on a variety of scales, plus a list of weather satellite tutorials.

NOAA NWS CPC Hazards Assessment Briefing map for North America

NOAA NWS CPC Hazards Assessment Briefing map for North America

NOAA NWS Aviation Weather Center

NASA's "World Wind" program--access to the 3-D topography of planet Earth, with the option for weather overlays.

Some weather tutorials:

Tutorial on clouds and precipitation from the University of Illinois's Department of Atmospheric Sciences.

An enormous collection of meteorology links from the University of Utah's Department of Meteorology.

"Chapter 7--Stability and Cloud Development"--these excellent lecture notes help to build an understanding of how to predict convection from a sounding chart, such as those produced by the MM5 weather model.

"Skew T diagrams: new tools for vertical analysis" by Craig Sanders, from the January 2004 issue of "The Front" -- this article is primarily intended to help pilots of powered aircraft use these diagrams to avoid icing, etc. Focuses specifically on the Rapid Update Cycle sounding diagrams.

Tutorial on upper air sounding details from UNISYS

Tutorial on sounding diagrams from Texas A & M University

Some more weather tutorials: Lifted Index tutorial, Notes on the temperature profile of the lower troposphere, Superb collection of weather tutorials by Jeff Haby, Home page for "The Weather Prediction . Com"

Some interesting articles on soaring weather by Peter Kelly:

Lift for Soaring - the atmosphere, types of lift, tips on each type of lift
Soaring Weather Talk - Discussion of weather products, and how to forecast lift
Soaring Weather - List of Links to products used for forecasting
The Thermal Soaring Adiabat Chart (and other info about lift)

Some weather links for other regions:

Kansas weather links: Soaring forecast for Wichita, NOAA weather discussion for Wichita region, NOAA forecast for Wichita, NOAA forecast for Yoder (near Sunflower gliderport), visible satellite loop centered around Wichita, infrared satellite loop centered around Wichita, Access to NOAA forecasts for other locations in SE Kansas, Aviation weather from NOAA NWS Wichita Field Office, River levels for SE Kansas, Kansas Road Conditions (511)

Weather links, other hang gliding resources, and more for Utah and Nevada

Weather links for Rota, CMNI

Oregon weather cams:
Cannon Beach
Oceanside
Cape Kiwanda (KGW)
Lincoln City (KATU) (this webcam lacks a time stamp and appears to frequently go for many hours between updates)
Yaquina Head (OSU)
Yaquina Bay Jetty (includes wind info which is same as given for Yaquina Bay Bridge) (ODOT)
Yaquina Bay Bridge (includes wind info which is same as given for Yaquina Bay jetty) (ODOT)
Newport Embarcadero (KGW) (this webcam lacks a time stamp and appears to frequently go for many hours between updates)
HMSC at Newport (includes current conditions)
Sea Lion Caves (with navigation to current conditions-- caution, the wind report seems unreliable)
Florence (Lane County)
Coburg Hills (from Springfield) (Register Guard) (not working when last checked)
Medford
Pine Mountain (includes current conditions)
Pannable webcam in Bend (good for looking at wave clouds)
Another webcam in Bend (similar to above, not pannable without passwords)
Collection of webcams for central and northern Oregon Cascades region including views of Mt. Bachelor, Pine Mountain, Sunriver/ Three Sisters, Eagle Crest near Redmond, Hoodoo Butte, and the Hood River area. Includes some views suitable looking at wave clouds.
Lakeview (ODOT)
I-84 at Lorenzen road (NE OR) (ODOT)
Navigation to all Oregon Department of Transportation webcams (only a few of these include a good view of the sky)
Webcam at Lenhart's airport (there is a wind sock near the treeline)
Webcam at Morton WA (includes current conditions)
Mt. St. Helens Volcanocams
More Oregon webcams

Distant weather cams:
Grand Canyon AZ
San Francisco Peaks AZ
Sedona AZ
Monticello UT
Cimarron NM
Wichita KS (click on small picture in upper right)
Orlando FL
Click here to find weather cams anywhere in the US
Colima volcano