video 1Comet ultralight glider with fairing, tow to 1100m

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Aesquire

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Nice! Good talent on that team, I've flown with Eric.

Without spoilers/air brakes that eats up a landing field. Hope the price is less than a F-35.
 

jedi

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Sahuarita Arizona, Renton Washington, USA
High performance and high price. I am looking for a practical aircraft, one that can be flown into and out of many areas and easily transported. Guess I need more of a powered paraglider.

Still interesting though. Just too much work for limited usefulness. It reminds me of a high fashion lady, nice to look at but not good to own.

I like the idea of the foot launch but 65 kg is a bit heavy and it sounds like that is not achieved yet. Add the motor on and it will likely wheels only most all of the time.

I would settle for half the weight, half the cost and half the performance. Then add the motor and see if it could still launch from a level field or a hang glider launch. Result: Fly five times more often.

Anybody else agree?
 
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Aesquire

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I would settle for half the weight, half the cost and half the performance. Then add the motor and see if it could still launch from a level field or a hang glider launch.
Half the performance is still decent local soaring, as long as you don't want to go much more than, say, 400 miles a day. :)
65kg is more than I want to run with. About half is in Hang Glider range.
But as is, performance is right up there with a classic training glider, and a better sink rate, which is the key, IMHO, to more soaring days in lighter winds. A hang glider tow plane should be just fine, and electric? Self launch is a game changer.

Although, ( Braces for Flames ) I suspect the price of the electric system will be significant, and my first thought is a Paramotor back pack rig would adapt pretty good, as a "engine & gear" bolt on to the foot launched version. Or an entirely new enclosed pod.

The advantage of a removable pod vs. integrated, like a "regular sailplane" is the ability to change as desired. You do get a performance hit, but if I had to chose between 40-1 and tow, or 33-1 self launch, well, excuse me while I mix up this 2 stroke oil.
 

John.Roo

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Letohrad / Czech Republic
Summary of techical data from their web:
65 kg weight
L/D 1:36 (1:40 in case of "glider version")
Wing span 15 m
Wing area 11.5 m2
Vne 140 km/h (170 km/ for "glider version")
Any idea of price?

I just don´t like so much the stick from top and vissibility. In thermals with other gliders you must have as perfect as possible vissibility of upper hemisphere. And I miss efficient airbrakes.

I also agree that without self launch system is not interesting. I am also lazy to run with 65 kg weight from top of hill :)
 

nestofdragons

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Near Antwerp, Belgium
Jim Marske had a homebuild glider (Monarch) with a control stick like this. His later model had a normal stick.

65 kg is a lot. But remember the hangglider SWIFT (first generation) was 55 kg. Good winds at launch sites make it less heavy for the pilot of course. It might be a good competition for the current hangglider winners in this class. I keep following the progress.
 

patrickrio

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From their Facebook:

1comet prototype nr2
There are no major aerodynamic changes as prototype nr 1 flies well. At first glance you may note that we modified the shape of the vertical stabilizer. Not for aerodynamic reasons, but in order to reduce torsion loads on the tail boom. The tailboom gets lighter and the CG of the glider moves further to the front.
The wing is now equipped with speed brakes deployable up to VNE. For practical reasons the spoilers mounted on the cabin of prototype nr 1 could not be built as big as calculated. So they lacked efficiency.
The Mitchell Wing like hang-stick of prototype Nr 1 was replaced by a more conventional Swift-like side stick mounted on the down tube. We invested 2 years in engineering and in hundreds of hours of FEM calculations. This allowed us to optimize the inside structure: lighter, safer and simpler to produce.
What remains unchanged: The nice laminar wing, the all-over sandwich glider like surface, the sleek cabin, the forgiving stall characteristics and the fast roll rate.


1617190205094.png
 

patrickrio

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My favorite part of the design is it's basic modularity. Tail feathers, boom, wing, pod, (propulsion). The layout combines well with current rapid prototyping technologies for composites and potentially speeds up the design-build-test iterations for these components as well and dropping iteration costs.

I think that a true rapid prototyping shop for something like this is almost within financial reach of garage hobbyists. Obviously a garage hobbyist doesn't have the expertise this project has, but the modularity means a hobbyist can specialize on one area and test optimizations... and have a higher chance of actually improving that part.

I think it also more easily allows mission change testing on the same platform. In all cases... once you get a component mission optimized it is easier and cheaper to move the better perfected tech to more integrated airframes.
 
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John.Roo

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From their Facebook:

1comet prototype nr2
There are no major aerodynamic changes as prototype nr 1 flies well. At first glance you may note that we modified the shape of the vertical stabilizer. Not for aerodynamic reasons, but in order to reduce torsion loads on the tail boom. The tailboom gets lighter and the CG of the glider moves further to the front.
The wing is now equipped with speed brakes deployable up to VNE. For practical reasons the spoilers mounted on the cabin of prototype nr 1 could not be built as big as calculated. So they lacked efficiency.
The Mitchell Wing like hang-stick of prototype Nr 1 was replaced by a more conventional Swift-like side stick mounted on the down tube. We invested 2 years in engineering and in hundreds of hours of FEM calculations. This allowed us to optimize the inside structure: lighter, safer and simpler to produce.
What remains unchanged: The nice laminar wing, the all-over sandwich glider like surface, the sleek cabin, the forgiving stall characteristics and the fast roll rate.


View attachment 109136
Air brakes - 👍
Side stick instead of "stick from roof" - 👍
So... any idea of expected price?
 

henryk

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krakow,poland
Pod iteration idea.... F1 CF crash cage covered in this plastic aero shell.

=more technical data...
 

peter hudson

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May 24, 2020
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66
I've been working on conceptual design for a 15M self launching electric sailplane that weighs under 120kg. It's not too easy. I've been watching the 1comet for a while as encouragement that it can be achieved! In my case it has more design features to make it easier for homebuilding, and less dependent on complex curved molds.

Many parts do have an expectation that the builder (me) has at least a CNC router and resin infusion skills. I expect a fuselage pod, canopy , and wingtips to be the only complex curved molded parts. Everything else can be ruled surfaces and sheet/former temporary molds.
 
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