Ground-effect gliding

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In ground-effect hang gliding as a focus (abbreviated to ground-effect gliding (GEG), the pilot intends to stay in positive ground-effect assets. Although ground-effect gliding occurs during the launch and landing of most (not all) flights of other hang gliding types of flying, the pilot who intends to launch, fly, and land in ground-effect assets joins a special GEG community and faces a set of challenges of design to meet the safety and enjoyment aspects of GEG. GEG occurs going slow as well as going fast. A GEG pilot might select equipment and sites with slow flying in total focus; another GEG pilot might select equipment and sites for faster flying.

Contents

Patents facing GEG challenges

GEG2.jpg

GEG flying craft design and development

  • "To get the most benefit from ground effect the closer the wing is to the ground the better. With the pilot suspended below the wing it limits getting close to the ground. The optimal height for ground effect is one foot for every twelve foot of span. To this end it would be much better to have the pilot on top of the wing and clear of ground obstructions. Such a design could be fitted with wheels with the pilot in a hatchway allowing him to run and push on the glider to gain flying speed." Note from Tony Prentice, developer of hang gliders since 1960.
  • During the development of pilot-powered aircraft on flat airstrips, pilot-above-wing was considered carefully; upon gaining airspeed and stopping pilot-power inputs, some momentary gliding would occur; the main intention of such pilot-powered flying was powered flight, and so such would not be full-session GEG. Kiceniuk was also a contender for the first Kremer Prize for human-powered flight. His human-powered aircraft was actually a ground effect vehicle that flew only inches above the ground. He later worked with Dr. Paul MacCready on MacCready's Gossamer Albatross.

What are the special enjoyments of GEG pilots?

  • Close-up photography occurs easily.
  • Strong odors impinge on the pilot's receptors.
  • Launchings and landings mount in count more easily than in other sorts of hang gliding.
  • Staying up in flight mode can occur when wind conditions and slope are well selected.
  • The land flashes by fast.
  • Exhilation of many launches and landings.
  • Potential of skip GEG (SGEG) where craft is designed to touch down with low friction (absence of grab) and then getting airborne again; repeat many touchdowns in one flight down the slope.
  • For FGEG, seeing just how far one might fly before touching the level ground by part of the craft or pilot. Craft design makes a difference. Pilot skills matter. Practice and good coordination are part of the challenge space.

GEG Safety

  • Being ever near the ground while gliding has its safety concerns. GEG in full calm with slow craft on groomed slopes with cares for meeting the ground safely and skillfully upon landing can be challenging. There are many reasons aircraft normally want to stay far clear of the ground; but in GEG, the pilot stays in a tight connection with the ground. The closer to the ground, the more one cares to choose the smoothness of the land that one flies over; being 12 inches off the ground for a mile would mean that one would not want to suddenly come upon a 13-inch obstruction. Vertical changes and perhaps oscillations become more critical relative to closeness to ground; a change of down 4 inches when flying at 3 inches above ground level (AGL) puts one underground!
  • Contacting with the ground with wheels, feet, skis, rolling booms, siliconed flats, are attempts to prevent damaging and injurious sudden stops or crashes.

Flatland GEG or Flatland long gliding (FLG)

Flatland GEG (FGEG) has been practiced by many who later intend to get into non-GEG hang gliding; the intent of a particular run and lifting of feet off the ground is familiar to many non-GEG pilots as they first practice running with their new hang glider (usually in this instance the hang glider is designed to do non-GEG hang gliding. In the literature "flatland long gliding" (FLLG or FLG) has been described; such FLG is a GEG that has a focus on getting long glides when on flatland only, that is, no slopes are involved in FLG; ideally the land is truly level. Precisely, though, FLG can occur beyond ground-effect, so a proper subset of FLG can be GEG; for instance, the FLG that places the high-hat wing up out of ground effect would not be GEG.

FGEG stays in ground effect for launching, flying, and landing. Long-jumpers in official track and field competions ruled by such as the Olympic rules are not allowed to carry devices like wings or weights that might give distance advantage to the long jumper. However, aside from those rule sets, a long jumper who does use wings to aid in the gliding lengthening of his or her jump flights begin to be in the GEG community. Distance records could be established for FGEG in many categories (pilot weight, wing weight, age, gender, altitude above sea level, etc.).

http://ozreport.com/forum/viewtopic.php?p=89209 Discussion some and image.

Slope GEG

Short or very long smooth slopes for GEG may be naturally found or artifically manufactured or groomed. A slope for GEG may be commercially operated, part of a public park, a public street, or private land.

When is hang gliding not GEG?

Defining thresholds for GEG is part of the adventure of exploring GEG. Notice that it is possible to hang from a wing while the pilot's body is set hung within a wing chamber and even hung in a way that the pilot's body during gliding is actually above the wing.

GEG Records

Who holds what GEG record? What are some feats that might be attractive to GEG pilots? The FAI does not yet recognize GEG as a distinct category of records; however, that won't stop GEG pilots from recognizing special achievement!

Timeline of GEG

  • 1971 GEG was recognized as a special activity by editor of Low & Slow hang gliding periodical.
  • 1973, March 5: Roger A. Oberle filed instructions that resulted in an approved patent; he gave focus to GEG in his instructions.
  • 2010, June 14, GEG gets a featuring at this wiki in HangGliding.org to celebrate the founding of Hang Gliding Association of America (HGAA) in partial memory of the Ground Skimmer periodical of the early 1970s that followed a club's growth out of the Self-Soar Association world organization space and its Low & Slow that recognized GEG as a special category of hang gliding.

Questions open for answerings

  • Q1. Did Otto Lilienthal get out of ground effect flying? Did he intend being in GEG?
  • Q2. Did anyone at the great Otto Party of 1971 get out of ground-effect flying? Did any of the pilots intend being solely a GEG pilot?
  • Q3. Is there any agreement as to when a pilot is considered to be flying beyond ground-effect? Is there any motion to standardize the meaning and threshold of ground-effect for GEG participlants?

Quotations found in the GEG world

  • If we live by the Spirit, we should also fly by the Spirit.
  • If you are led by the Spirit, you are not under the law of gravity.

External GEG-associated links

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