| Rigid Wings |
New Rigid Wing
Seedwings is currently designing a new footlaunchable rigid wing that is foldable and car top-able. It is designed to close the gap between hang gliders and sailplanes. Although we are not yet ready to share in public more detailed information, we are interested in the personal exchange with interested pilots. If you would like to talk with us about this new craft please do contact us. The above image shows the new rigid wing in configuration with an integrated pod. However, Seedwings is still very much committed to the prone, free-in-the-air style flying and our new rigid wing can be flown with a control bar and the pilot hanging prone under the wing.
Our Vision for the New Rigid WingOur vision is a wing that performs like a club sail plane and can be launched and landed like a hang glider, and does not cost significantly more then a high performance hang glider today. Improved performance, on the other hand, allows more cross country distances at far more flying sites, usually closer from home. The major downsides to sailplanes are their high costs, portability and that they will usually have to be landed on at least an improved grass airstrip, to prevent damage. In essence, this means most sailplane pilots hesitate to even try cross country flying, because they do not want to damage the club's glider or tie it up for the duration of the retrieval from a remote airport.
The Original PetrelThis is how Bob Trampenau and Seedwings started 35 years ago, with the original Petrel. It was planned to be built mainly of fiberglass with carbon spar caps. Its wing was to be wire braced from the bottom and cantilevered in the negative direction with a span of 12 m or 39.36 feet and a wing area around 110 ft.². It was planned to use Fowler flaps increasing the wing area and camber for takeoff, thermaling and landing. Quite a bit of thought went into the pilot position arrangement. The result was a cockpit where with open clamshell doors the pilot could do a 360, head over heels even with the canopy closed, harnessed to a padded parachute harness, hooked into a belly yoke and pinned into the sides of the fuselage. This would allow the pilot to run, fall forward or be seated at any time unobstructed. There would be rudder pedals and side sticks for control. At that time the empty weight was targeted at 125 pounds. The way it worked out was for a good reason, it should be built a little differently now. In the meantime the sport of hang gliding has advanced a tremendous amount. What we have today in hang gliding has taught us a great deal about design, construction and flying hang gliders. The Petrel has been on the drawing board ever since the 70s. It's gone through several revisions in aerodynamics, wing geometries and construction methods. It's an ever exciting challenge to think of how much performance and fun can be enjoyed by running down a slope on a mountain and soaring up into the air. Specifications: Original Petrel in 1975 |
|||||||||||||||||||||||||||
| Petrel | 12 meter | with Fowler flaps | |
|---|---|---|---|
| Span | 39.4ft, 12 meter | same | |
| Area | 110 sq. ft. 10.2 sq.m | 140 sq. ft. 13 sq. m | |
| Aspect Ratio | 15.5 | 11 | |
| Glider empty Wt. | 125 lb. | ||
| Glide ratio estimated 25 to 1 | |||
| Minimum sink depending on flap setting estimated 100 to 120 ft./min. | |||
Speed range 20 –75 mph VNE | |||
The Sunseed flying wing
Rigid wing hang gliders are a bridge in the gap between sailplanes and flex wing hang gliders. The original Sunseed weighed only 55 pounds and might not have passed HGMA airworthiness loads tests today, but the third prototype however was noticeably stronger than the first prototype flown. A rigid wing with a king post and wires is the least expensive, lightest weight just like that of king posted flex wings. The current market for rigid wings however, is predominated by topless and cantilevered configurations where as the market for flex wings utilizes both. The Sunseed was from an era where king posted rigid wings were popular mainly because flex wing performance was less at that time and it was seen as a means to higher performance. Even though estimating the Sunseed's glide ratio at 14 to 1, it was easy to see in the mid-70s that flex wing development would surpass the performance of king posted rigid wings with all those tubes and wires.

