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THE NEW DLG "C O N C E P T" INTRODUCTION

We Proudly introduce the very new "CONCEPT"
To provide better chances for all of the not so well trained and experienced DLG fans as well as for the worlds top DLG-Pilots, we have carried out comprehensive research to find any further possible improvements in gaining more altitude by reducing energy losses during the early stage of launch.

Based on the very clear result, we found an epoch making clue to reasonably improve the "efficiency factor" given by the limited human body power and design features of the model in use vs. throw height by reducing still present but actually avoidable drag, as it appears to be common in any conventional modern DLG design. The result we call just "CONCEPT"! What is the peculiarity in it?

More sophisticated throw analysis has revealed a dramatic weakness which all of the "state of the art" designs have in common.... or better, suffer from physical principles and properties during the "DLG" or "SAL" launch, (where really terrible things are going on) which haven't been watched closely enough before.

What does that mean????? Simply up to 40 % of throw energy so far was and still is wasted by conventional designs, which could be used to gain considerably more throw height otherwise....

We all know that during the circular acceleration all masses of- and inside the model will maintain this circular motion after release and therefore delayed transition into the straight climbing path. Nothing and nobody can ever overcome this very physical principle! Therefore a SAL glider features a somewhat oversized ruder fin to stabilize and dampen "rocking" movements (at least a half swing) caused by circular inertia.
During this (at least half) swing something more dramatic happens...... This "side slip" causes considerable increase in drag and therefore a slowing down of the wing and the more heavy fuselage masses below the wings mass center. The more heavy Fuselage masses will induce more kinetic energy which generates a force momentum to cause the model to roll (we call that "rock'n roll), generating even more drag which exceeds the side slip drag by several times, gulping up to 40% of throw energy, lost for the conversion into height.

How the NEW "Concept" can help?
1) As mentioned before, we can do nothing about the "rocking" but there is a very effective cure against the by far more dramatic "rolling". HOW? Simply by bringing the mass / force centers as close as possible together to reduce or even eliminate the roll momentum.
In case of the "CONCEPT" this goal could be achieved by putting the wing mass center to the closest possible distance to the Fuselage mass center..... Therefore the wing was placed very unconventionally UNDER the fuselage where it belongs anyway to match any physical conditions during a SAL launch.

2) This measure even can reduce some drag of the fuselage surface during the "rock" where about 40% of the fuselage front part is in a "wind shadow" behind the wing, saving further precious throw energy in amount of ~40% of the fuselage drag.

3) The fuselage front part is designed as a "LIFT BODY" featuring a airfoil shape with more width than height, adding some lift and reduced drag to the total performance.
The Canopy has been unconventionally placed in a 90° shift to the side of the fuselage front. Not only that this measure is the only way to provide enough space for servos and RC installation.....The fuselage surface which faces the flight path during the "rock" is free of any gaps by the canopy fit, hence saving even more energy.....

TO CONFIRM THE "CONCEPT" functionality, we have adapted the wing, tail boom and tail surfaces of our "OPIUM" to have a direct compare between booth Low- and High wing configurations.
The analysis of the flight tests showed a result even better than expected......
The "CONCEPT" generated an exceptional increase in throw height in average of 15-20% in compare to the original OPIUM which was launched under the very same conditions by the very same person.