Revision History for "The Lever Link"

• 2009-Dec-22 00:00 MDT
  • Updated "last-edited" date.
  • Fixed minor XHTML typo (one missing </li> closing tag) which was causing the page to fail W3C validation.
• 2009-Jun-17 22:00 MDT
  • Updated "last-edited" date.
  • Fixed typos in first paragraph of "New Thoughts" section. Changed "is will move" to "it will move" and removed redundant "with good effect".
• 2009-Jan-29 23:00 MST
  • Updated "last-edited" date.
  • Added the term: "aerodynamic" to discussions mentioning control surfaces to clarify the idea that the floating keel is in fact, a mechanism that can actively warp the wing to achieve roll forces comparable to ailerons.
  • Added links to the forum threads which discuss the Lever Link idea as a note to the "Forward" section.
  • Added a new "Con" to the Pros and Cons section; that is, the Lever Link may make gliders more prone to spins. Also added this as a "Pro" because aerobatic pilots might like this capability. (Thanks to my Dad (William H. Roberson), for pointing this out to me. Note that he was a B-24 pilot during WWII and later an Engineer, so he knows a bit about both aircraft design and pilotage).
  • Changed wording in "Assumptions and Glider Configuration" section from "crosses over" to "passes over'.
• 2008-Aug-07 15:30 MDT
  • Updated "last-edited" date.
  • Added a note paragraph to the "On the mechanics of Hang Glider roll control" section describing how the force of gravity and the aerodynamic force are actually resultant forces.
  • Reworked the text of the "On Forces and Moments" section to add clarification.
  • Added summary paragraph statement to the end of the "The keel really wants to float!" section.
  • Added a note paragraph acknowledging that billow shift on a bladewing will likely manifest as differential washout.
  • Reworked the "Forces on the keel" section. Added "Basetube push/pull" forces diagram and discussion of the undesirable sideways force from the rear flying wires.
  • Modified the "Lever Link Design #2" section to better illustrate the significant force amplification made possible by the Lever Link principle. Reduced the pilot weight and changed the Lever Link geometry to increase the force amplification to 11X.
  • Fixed duplication of Figure 10. (Changed "The 'Plate' Lever Link in 3d" diagram to Figure 11.)
  • Added a sentence saying that the "Plate" design is probably the best design presented.
  • Added a "Performance could be improved by using a shorter pendulum" bullet item to the "Pros" section.
  • Swapped order of "Pros and Cons" section data.
  • Added revision date code to this revision history webpage title.
  • (HTML/CSS) Modified HEAD meta tags.
  • (HTML/CSS) Fixed all instances of self closing tags missing a space before the "/>".
  • (HTML/CSS) Changed main DIV element ID attribute from "content" to "wrap".
  • (HTML/CSS) Changed "border:0" to "border:none".
• 2008-Apr-26 10:00 MDT
  • Corrected reference to the control bar geometry which provides an elevated virtual hang point. The control bar/flying wires geometry actually resembles a "Pitchy" and not a "French Connection" as was erroneously stated in the previous version. Thanks to Karl Stice for pointing this out.
  • Added credit to "Darlet" as inventor of the French Connection.
  • Added revision date code to webpage title.
• 2008-Apr-24 22:00 MDT
  • Initial posting.