The goal in the development of our tandem hang-gliders was, to develop a wing, which through modern sail design together with stiff wing-tubes has little twist and can be flown comfortable and with confidence, with low bar pressure in UL-tow or fast flight. New standards were to be set for general tandem gliders in sink and glide performance.
Since modern tandem training wings have to carry, besides both pilots, sturdy landing gear, bigger emergency equipment and special harness systems, the wing should still be light, but capable of a high surcharge and sturdy construction for training operations. The result speaks for itself: The BiCo weighing 42kg [93 lbs] can be loaded after model test and certification with min. 187 lbs and max. 523 lbs [80 kg and 237 kg].
This opens up a wide range of applications.
The BiCo despite its weight is well balanced on the shoulder and easy to launch with passenger as well. Since the BiCo has light control pressures in normal flight, a slight pull on the base tube is all what is needed to increase speed. The wing accelerates instantly.
Launch with landing gear or start-cart/dolly
Even on wheels or start-cart and dolly the BiCo does not need a long runway. The wing has, according to tow-pilots testimony, a similar behavior as solo hang-gliders. Correspondingly the wing gains with the UL quickly in altitude too. Control-bar pressure under tow is moderate and comparable to that of a solo glider. A tow assist bridal may be dispensed with.
Starting under engine power
The BiCo is well suited for a solo trike wing, as minimal motorized two seater wing and as tow-trike wing. For a tow-trike the engine output can be reduced, because of the large sail and the slow flight-speed; thus hang gliders have no problem to follow the tow-trike. Special tow-trikes are presently developed and tested by various manufacturers.
The BiCo has compared to common two-seater wings less twist and distinctly more sail-battens top and bottom. The glider is tracking true and is good controllable over its full speed range. The neutral turning characteristics install instant confidence and grant thermal flights with surprising altitude gaining performance. In headwind or fast flight the good glide performance is convincing.
The landing approach begins at higher altitude with repeated determination of the wind direction. Only after one is sure of the wind direction, one should set final approach direction and also stick with it. Glide in straight with extra speed into the wind and let the wing loose surplus energy in ground effect. For foot landings change hand position when the glider is flying straight at trim speed. Till flair time keep legs bent back and a hollow/straight back. The BiCo has a long final glide and the stall is soft and friendly. The nose pulls up almost by itself finally.
The BiCo comes within a round speedbar and the corners are easy and cheap to repair. When learning hanggliding, it sometimes comes to little accidents and therefore we have kept it simple...
Upon our clients request, we have once upgraded a BiCo with a bowsprit to have a crumple zone in case of a crash. The flight teacher and trainee pilotes appreciate this little detail very much as the pilots swing underneath the nose instead of crashing into the glider. Should you wish your BiCo to be equipped with a bowsprit, you can order it as an optional extra.
Max Take-off weight:
Sail leading edge grid or matrix:
185 sqf [17.2 sm]
31.5 ft [9.6m]
Top 22 + 1 nose batten, Bottom 8 + 2 folding tip battens
3 each side
1 each side
92.5 lbs [42 kg]
523 lbs [237 kg]; (Test: Pos. 3420 lbs [1550 kg] Neg. 1720 lbs [ 780 kg])
615 lbs [279 kg]
leading edge PX 10, Upper sail 5 oz Polyester, Lower sail 4 oz Polyester
ca. 17– 23 mph [27-37 km/h]; dependent on load
56 mph allowed [90 km/h]
167 – 236 ft/min [0.85 – 1.20 m/s]; dependent on load
ca. 1 : 13 at 22 mph [35 km/h] with min. load, ca. 1 : 10 at 29 mph [46 km/h] with max. load