agile +++ suited to daily use +++ elegant +++ ergonomic +++ flexible +++ harmonic +++ comfortable +++ light weight +++ optimized +++ safe +++thermal-sensitive +++ variable +++ open

Antares 23: Amenable to anything. The happy medium. No compromise.

Thoughts about the „Open Class“

Since its introduction in the 1950s, especially the oldest competition class has always been the one that represented the biggest innovation – unregulated und therefore open to any - be it - extensive (and expensive) solution. Their technologic top-rate performance in the sailplane industry is not called “super orchid” for nothing. This expression stands for something truly extraordinary and technologically “exotic”.

For more than a decade a simple formula was effective: a bigger wingspan automatically means a higher glide ratio, and thus higher performance – until some ten years ago a more than 30 meter wingspan would correspond to a best glide of 70. The expectations were high.

But realized and realizable performance would then be disproportionate to the necessary work input: the costs are immense and therefore the lot size could be just small. What’s more a larger wingspan requests a higher stability and therefore will, despite all material- and manufacturing-innovation, be heavier. A higher weight means higher inertia, which in any case rises with the square of the wingspan. Plus, carrying additional weight is not only awkward in the air but also handicaps any necessary movement on the ground.

A big sailplane’s inertia especially affects its circling characteristics, and with large wingspans another problem arises: while the inner wing is circling relatively slowly, the outer one flies fast – very fast when you pilot a very large wingspan. On a 30 meter wingspan the speed difference in a thermal when banking at an angle of 45 degrees may measure 40 kilometers per hour. Circling really steep and at the same time slow to catch the best climb in a narrow thermal is reserved to small gliders.

Those significantly smaller open class gliders, for example the 21 meter ships, do have obvious advantages when thermaling. However in weak or turbulent thermals their very small average wing depth is aerodynamically disadvantageous (small Reynolds Number).

Therefore it is good to know: The past years have revealed that 23 meters are clearly the optimum recommended for our Antares 23’s wingspan. Three times European champion Peter Harvey (GB) flew the Antares 23T prototype (still with the Antares 20E’s shorter fuselage) at the WGC 2012 in Uvalde/Texas. And he did not win three days out of the blue - on day 7 he flew a 553 kilometer task averaging at 161 km/h! Moreover he won the Robert-Kronfeld-Cup!


  • Not merely wingspan raises the performance, but an optimized aspect ratio does
  • There are some extreme movements in the open class, some use very large some very small wingspans.
  • The optimum can be found between the extremes, without compromising: Antares 23

The proper engine for any purpose

Electric engine for the Antares 23E

The patented propulsion unit which is a keystone for the Antares-concept was especially designed for our Antares. Lightweight and environment friendly batteries, a brushless electric 42 kW external rotor motor, state-of-the-art power electronics and a large-sized low-speed propeller had been designed as a complete system for Antares 20E. It was subsequently adapted to her bigger sister Antares 23E. For years, Lange Aviation has now worldwide accumulated the leading know-how in off-the-shelf electric propulsion systems for light aircraft.

Antares 23E – performance and independence!

Reliable sustainer unit for our Antares 23T

The well-proven Solo 2350C engine’s 30 hp and a specially proportioned big propeller with a diameter of 1.36 meters take care of a good climb rate, which also applies to flying in higher altitudes and at higher temperatures. Due to a straightforward engine handling your flying is stress-free. An optional starter adds to perfect reliability. The propulsion unit weighs only 55 kilos – without water ballast an Antares 23T has a wing loading of only 34 kg per square meter. The fuel tank carries 16 liters – good to fly an hour under full load.

Antares 23T – exceptionally variable wing loading for the „open class“!


Not only are our two different motorization alternatives responsible for the Antares 23’s high flexibility.

With an extremely big spectrum of different wing loadings ranging from 34 to 58 kilos per square meter especially the Antares 23T's variability seems to be unrivaled. The version which is optimized for contest flying has no less than twelve individually controllable, hands-off coordinated wing tanks as well as a fin tank, which may be emptied in 4 steps - a total capacity of more than 353 liters. The tanks may smoothly be regulated according to any weather situation, without having to change the optimal center of mass. Our Antares 23T can thus at high speeds well keep up with any competing wing span, and its best glide is - flying an impressive speed of 148 kilometers per hour - at 60.

Best climbing qualities, excellent gliding performance even at high speeds, most efficient in thermals as well as non-problematic handling characteristics.

Extreme concepts tend to malfunction; sometimes they are not that practical. However we are offering an optimum solution between the extremes, without taking any prisoners. Weak weather in spring or during fall time, strong days in the peak season – at the same moment it will at all times be suitable for daily use, and it is an insiders’ tip for contests.

Antares 23 – this means major technological expertise in designing ultra light and high tensile structures, high construction quality due to our large and continouosly growing experience in the serial production of the Antares-family, permanently enlarged service - well,... that's Lange Aviation.