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What times have u guys been getting? I've been getting 15 sec.

Not on ELG myself, but at SoCal State, my teammates got 29-31 seconds and ended up with 1st.

Indiana's winner, Thomas Jefferson MS, had a string from 27 seconds to win with a score of 81. Used a five joint polyhedral wing and weighed 4 grams. Not a flapper and not a kit.
Tom

fifty_missions wrote:Indiana's winner, Thomas Jefferson MS, had a string from 27 seconds to win with a score of 81. Used a five joint polyhedral wing and weighed 4 grams. Not a flapper and not a kit.
Tom

How big are your wings , and how high was your testing area?

The wings on their state competition airplane was basically made from 3/32" thk X 3" wide X 30.5 cm before dihedral was added. The state site was 60' high. They are heading to nationals which has a decent footprint but 30' high. Means a new airplane. They have had nice luck with the SO glider kit from RC Retro in MI. There times are around 20 seconds+/-. So I set about working on a new design for them and we tested the prototype today. Its called the ELAN (Elastic Launch Aero Nominal). It came in at 3.21 grams and uses various features that have been proven elsewhere with Bill in Atlanta and Kurt in Illinois. This was the first to use the launch grip tab under the wings and canted wing tips to reduce vortex drag. It is a flapper and we developed a new technique for sanding and polishing the wood surfaces. It was tested at a fieldhouse today with a 30' ceiling and eventually was doing 28-30 second flights which they were happy with. They will build at least 4 more to get them trimmed out before heading off to Wisconsin.
The leading edge of the wing was set at 1/2 degree positive and the stab at zero degrees with no tilt. For recovery into the transition and glide was an almost imperceptible amount of up elevator bent into the trailing edge of the stab. This glider has no carbon fiber and was built using "hobby shop" balsa wood carefully screened. I might add that a large majority of the wood was removed using an electric palm sander with fine grit sandpaper. Though it goes against the norm, the palm sander actually allows some ham-fisted builders a chance consistency. Various magic marker lines were drawn on the top and bottome surfaces to help monitor material reduction.

Tom