With each advent of spring, when the air is alive with innumerable happy creatures; when the storks on their arrival at their old northern resorts fold up the imposing flying apparatus which has carried them thousands of miles, lay back their heads and a


California Condor over Grand Canyon--Photo courtesy of Christie Van Cleve                          Juv. Bald Eagle near Peterson Butte, OR

“With each advent of spring, when the air is alive with innumerable happy creatures; when the storks on their arrival at their old northern resorts fold up the imposing flying apparatus which has carried them thousands of miles, lay back their heads and announce their arrival by joyously rattling their beaks; when the swallows have made their entry and hurry though our streets and pass our windows in sailing flight; when the lark appears as a dot in the ether and manifests its joy of existence by its song; then a certain desire takes possession of man. He longs to soar upward and to glide, free as a bird, over smiling fields, leafy woods, and mirror-like lakes, and so enjoy the varying landscape as only a bird can do.

Who is there who, at such times at least, does not deplore the inability of man to engage in voluntary flight and to unfold wings as effectively as birds do?

Are we still to be debarred from calling this art our own, and are we only to look up longingly to creatures who describe their beautiful paths in the blue of the sky?

Let us investigate therefore in a truly scientific spirit, without preconceived notions.”

--Otto Lilienthal, inventor of hang gliding, in "Bird Flight as the Basis of Aviation", 1889.



Hang glider in flight                                                                 Hang glider with rudder, Zagi RC glider with rudder and variable anhedral


Welcome to the aeroexperiments website!
Author: Steve Seibel
Contact: steve at aeroexperiments dot org
Website last updated: June 2008


The main purpose of this website is to share some interesting practical and theoretical ideas about the basic principles of flight in hang gliders, sailplanes, and airplanes. Some of these ideas go a little bit against the grain of the prevailing "conventional wisdom" among pilots. Most of the content on this website is based on a series of careful in-flight experiments, some of which may be easily repeated by any reader.


The content on this website is aimed at a diverse group of people, including pilots of unpowered and powered aircraft, RC modelers, anyone else with a special interest in the physics of flight, and those with an interest in raptors and other soaring birds.


Here are a few of the many topics currently addressed on this site:

Interesting links page including bizarre aviation experiments (winged man), interdisciplinary aviation/ bird study projects, useful pilot-oriented aerodynamics tutorials, more advanced aerodynamics pages (including special attention to yaw-roll coupling in aircraft with sweep, anhedral, and/or dihedral), RC sailplane links, hang gliding links, links to hang gliding and "trike" instructors in Oregon and elsewhere, Oregon weather links, and more.

Photos from the Oregon hang gliding scene

Notes and links on dynamic soaring

Brain teasers for those who believe that an aircraft can "feel" the wind direction in flight, or that downwind turns are "different" from upwind turns, or that an aircraft flies differently in "lift" than in "sink"

Notes for new hang glider and trike pilots and Notes for new airplane pilots

Other practical articles including notes on using a GPS in soaring flight, plus detailed notes on some features of the Garmin GPSmap 76S GPS, Garmin Etrex Vista GPS, and Brauniger IQ Comp GPS variometer.

Photos and articles relating to the "wrong-way rudder": attaching a rudder to a hang glider created a "backwards" coupling between yaw and roll, so that a left rudder input created a right bank and a right turn.

Photos and articles relating to the variable-geometry Zagi (ground-adjustable dihedral/anhedral). This aircraft also exhibited a "wrong-way" response to rudder inputs in some configurations.

Photos from two hours aloft with the engine off (wave-soaring a Cessna 152)

Semi-scale Me-163 Komet RC slope glider with rocket boost (photo courtesy of Paul Naton). (Article and more photos).

Notes on some themes explored in the aerodynamic theory and experimental results sections of the Aeroexperiments website

New feature: The Aerophysics Exploration Pages (still under construction!)

See for yourself--simple in-flight demonstrations that you can do to the explore the physics of flight in a "conventional" airplane

More articles dealing with the physics of flight in hang gliders and "conventional" aircraft: You can't "feel" gravity!, The myth of the slipping turn in hang gliding and "conventional" aviation (debunking the FAA's view of turn "coordination" etc), and much more (see sitemap).

Experimental data wanted from prone powered-harness pilots! (Proposed vectored-thrust experiments in flex-wing and rigid-wing hang gliders)

And more: see the site map for a full listing of content.

A note on site navigation: at present this site is designed to be navigated entirely from the site map. Near the top of each page is a button to return to the site map. For most other movements around the site, you'll have to use the "forward" and "back" buttons on your own browser. Since the content is a bit eclectic I haven't designed a "guided tour" (other than the links given immediately above) to spoon-feed the content to the visitor--but perhaps you'll find something that interests you! If you haven't come for something specific, you might want to start by visiting the photo galleries listed near the top of the site map. If you are a repeat visitor you might want to check the "log of additions and revisions" listed near the top of the site map. Enjoy, and thanks for stopping by.

Click here to advance to site map


Always remember: "Faith is an island in the setting sun... But proof... Proof is the bottom line for everyone!"

**** Note spring 2014: I've started an new, alternate home/ page / site map for the Aeroexperiments website, linked to some newer content. Click here to advance to the new home page/ site map.****


Copyright © 2004 aeroexperiments.org