1Comet, a high-performance, laminar-flow ultralight sailplane, debuted at Electrifly-in 2025 in Bern, Switzerland. Though looking somewhat like the Ruppert Archeopteryz, there are significant differences.
Both 1Comet and Archaeopteryx come in foot-launch and electric-powered versions. Both fall into the microlight category and are capable of flying in microlift conditions.
1Comet, though, has a broader weight range, from a foot-launched glider with fixed landing gear weighing a total of 165 kilograms (364 pounds) to an electric-powered, retractable gear machine toppin out at 350 kilograms (771 pounds).
Archaeopteryx has a removable electric motor behind the pilot, cleverly strapped in with Velcro fasteners. 1Comet has a fixed-position Front Electric Sustainer motor in the nose.
FES unit in nose provides sufficient power for self-launching and a strong rate of climb
The 1Comet web site makes the following claims for the electric-powered version. “The low weight also makes it the ideal platform for electric flight. With only 30 kg of batteries, you can stay in the air for over 2 hours or climb more than 4000 meters.
“The electric glider version with FES system can be loaded with up to 350 kg (MTOW including 100 L of water) and has a retractable gear. The foot-launch version comes with fixed gear.
Powered flight enables self0launches, and even, as shown at the end of this video, prompt touch-and-go landings. Note that the overhead control stick from the first test flight has been replaced with a more conventional side-stick controller.
What is Microlift?
According to Wikipedia, “The Fédération Aéronautique Internationale Gliding Commission‘s Sporting Code defines the classes for gliding competitions and records. One of the classes is the ultralight glider. These are defined as gliders with a take-off mass not exceeding 220 kg (486 lb). Examples of these are the Apis and Silent 2. Microlift gliders are a sub-type of the ultralight class, further defined by a wing loading that does not exceed 18 kg/m2 (3.69 lb/ft2).” (Editor’s Note: Some experts suggest that controllability issues arise at wing loadings under four pounds per square foot.)
“In addition to the traditional forms of lift used in the sport of gliding, microlift gliding also aims to exploit non-traditional sources of weak lift. In typical conditions, conventional sailplanes may be unable to exploit weak vertical movements of air. However a microlift glider that is specifically designed to have a very low rate of sink and a very small circling radius, may be able to exploit these feeble air movements for sustained flight and may even allow the glider to climb.”
1Comet’s designers show how low wing loading can affect circling radius, and thus, exploitation of those “feeble air movements.”
For a highly detailed analysis of the 1Comet’s design, see this presentation, given earlier this year by Donat Bösch, at the Interlochen SHV Festival. In it, he gives credit to Eric Raymond and Sunseeker 1, which 1Comet resembles and which benefits from Raymond’s skills with lightweight structures.
One important aerodynamic element was reducing the effect of interence drag from the joining of the wing and fuselage. The design team tried 15 different configurations and tested them using computational fluid dynamics (CFD) before settling on a high-wing layout applied a method of creating the least drag from that juncture.
Careful placement of wing above fuselage enabled creating least drag with iinterference between surfaces
Pricing and Availability
The firm is making the first batch of 1Comets available, with almost half pre-ordered already. The firm states, “The price (foot-launched version) of € 69,000 ($69,450 USD) ex works is guaranteed for the first batch of gliders, which means that the price guarantee is limited to the first 15 gliders. We expect the basic electric version to be about € 20,000 ($23,180 USD) more expensive.
“If you are interested in purchasing a 1comet, please contact info@1comet.com.”
1Comet sums up its craft in this synopsis. “1comet is a 15 m wingspan flaperon glider with a laminar profile comparable to that of a modern racing class glider, adapted to the specific Reynolds numbers. The original aerodynamic layout comes from Dr. Martin Hepperle and Dipl. Ing. ETH Donat Bösch. Eric Raymond served as a consultant for lightweight design. AeroFEM GmbH, a spin-off of Pilatus aircraft, made a complete CFD and FEM Analysis. Test flights were carried out by Sören Pedersen, an experienced glider and class 1 test pilot.”
With aircraft like the 1Comet, Swift flying wing and Archaeopteryx in the sky, the promise of microlight, microlift soaring may become its own competition class, with sailplanes able to compete with birds on their own terms.