A Case for an Electric Gyroplane Seaplane

[kolibri282]

Et pour 0 t/mn, la vitesse relative à l'air ne devra jamais excéder...0 noeud.

La question etait d'accellere le roteur apartir d'un vitesse de zero du roteur et de l'autogir. J'ai relu la reponse et comme je disait dans mon reponse #49 il est possible de demarrer un roteur si l'angle du disc est très large et si vous pouves controller l'angle d'attaque des pales, mais avec les limites impose par la geometrie d'un autogir et la friction dans le system je pense que c'est a peine practicable.

 

[Hodag]

If the regenerative braking on the rotor would not be useful for taxi, then it would have to be very cheap and not much heavier than existing brakes to be useful it seems.

 

[Hodag]

Takeoff from hydrofoils would seem to save energy. A "Quadrofoil-Copter" would look like a water bug. Make the 5 hp motor retractable for higher speeds to save energy then activate the big prop motor to reach takeoff speeds? I'm sure I would be an engineer's worst nightmare. The foils would need to retract completely for aerodynamics and stay up for landing probably. Although the Lisa Akoya uses fixed foils on the front. (https://youtu.be/UX6qhpIOyEw) Here is an example of 80 mph foils that cleanly retract. (https://youtu.be/xhUL37ITUwE)

 

[Hodag]

Here is an example of an adjustable thrust line and amphibious retraction. (https://youtu.be/51qgtQ-wqGE)

 

[birdy]

"That was presumably before the Big Bang, any gyro afterwards took off with the blades spinning, "

Love this blokes humour.

 

[Hodag]

The only thing I got out of that answer was a jet going 2.9 Mach couldn't make a rotor turn but Ken Brock could.

I'm kinda past that question, though. It would be better to not stop the rotor while water taxiing, making the regenerative braking on the rotor brake less useful.

 

[Hodag]

But, if you had to prerotate to go from boat to boat, some of that energy could be regained.

 

[Hodag]

A 5 hp Torqeedo is 16-18 lbs for an idea of weight. It may be worth the weight. Water is 800 times more dense than air and small foils or props are very effective, but must be very strong carbon fiber. It could be made to offer regenerative water braking and much needed reverse and enhanced steering. It may only move a gyro up to 15 kts without help, but that would save energy for multiple takeoffs if using hydrofoils. You would never need to engage the large motor if simply taxiing around on 5 hp.

 

[kolibri282]

The only thing I got out of that answer was a jet going 2.9 Mach couldn't make a rotor turn but Ken Brock could.

My answers are strewn with a few quips, David, perhaps because I was a bit overwhelmed by your enthusiasm. I don't want to sound condescending, I just wanted to point out that solving the one hundred and one problems you are currently tackling by trial and error might in the end take longer than learning the tools of the trade first and do it the way the great heroes of old did it, by applying sound but also enlightened engineering.

Good luck with your project!

 

[Jean Claude]

... avec les limites impose par la geometrie d'un autogir je pense que c'est a peine practicable.

Yes Juergen, c'est simplement parce que mu est forcément supérieur à 0.35 que nos rotor, réglés à 3° de pas, ne peuvent démarrer seuls sur nos nos autogires.

" it is simply because mu is necessarily greater than 0.35 that our rotors, set to 3 degree of pitch, can not start by themselves on our gyroplanes."

 

[ckurz7000]

Hi Hodag,

it's all been said before in this thread: an electric gyroplane on floats is probably the worst aircraft you could select to venture into the air with an electric motor. Regenerative braking is a miniscule effect, so don't even bother thinking about this before the big problems aren't solved.

Of course an electric gyro would have very desirable features compared to a conventionally powered one...if you disregard energy density and weight of batteries.

Of course, energy technology is going to improve over time. But until then, let's explore electric flight using platforms that are better suited than the most draggy and least efficient concept available.

And I say this as a big proponent of electric cars and enthusiastic gyro pilot.

Greetings, -- Chris.

 

[Hodag]

Juergen,
Thanks for the reply,
I too have a sense of humor and greatly appreciate your experience and patience. I am sure some things are lost in translation as well. I have never taken a Calculus course or seen a gyroplane "in person," but I have ideas that do not stop. I have spent my life on other pursuits that hopefully were not a waste. I consider fun from the prospective of an owner, costs and environmental concerns that an engineer might not. I have developed a base proficiency in communication, but only a little French and no German or other languages. It would take at least three engineering degrees for this project and my biological clock would not allow me the time. You may talk me into it though, Yoda said the same about Luke Skywalker. Perhaps I am just supposed to be the guy asking the questions, and I would have thousands more before completing a quest of this magnitude, or solving it for someone else's profit most likely. But I consider chatting the opposite of trial and error. We can solve many problems cheaply by talking first.

The reason for my confusion is that it would seem a light gust can move a stationary gyroplane's rotor (but perhaps insignificantly), and if a prerotator spins to 200-220 rrpm and flight rrpm is 320, what happens in between? Airspeed must be factor, according to this site at least (#4)(https://enewbold.com/gyroplaneQA.htm).

But if a static rotor is more resistant to wind than a spinning one, perhaps there might be a simple way to keep it from flapping without prerotation? It may not be a major issue, but I always try to find a way to make things better.

Smoothing out the ride with hydrofoils would help.

Jean-Claude,
Merci pour votre réponse encore.

 

[Hodag]

ckurz7000,

Thanks for the post,
I understand now that fuselage drag is less than rotor drag, so even if we eliminate the floats and make a sleek flying boat, there would still be much drag. Even if we just stick to the seaplane idea without considering electric for a moment I would like to continue this discussion. I am sorry if I hijacked your website but this idea had to come out. I felt the best place to start was here, with the gyroplane experts. The major ideas are not my own. England certified gyroplanes for commercial use, Sweden certified them on floats and Germany made an electric gyroplane. When taken together, it could be a game changer.

Step one: Receive massive grant from government, which I do not see happening if electrics are not involved.
Step two: Sell product endlessly back to all levels of government by keeping it affordable,which would also open a civilian market.

 

[EI-GYRO]

Just as a matter of interest, does ANYONE KNOW if the electric-powered gyro ACTUALLY
FLEW for 45 minutes.
We only saw a photo of two feet of air under the wheels.
Nobody had a video camera, phone, ????? Any link to video ???

I would love to have heard the SOUND, if only to evaluate the actual external noise reduction
compared to petrol.


Li-X batteries lack energy density/weight by a factor of 60, density/volume by a factor of 18.
The energy density is a little less than milk.

 

[Hodag]

More on the e-Cavalon: (https://blog.cafefoundation.org/electric-autogyro/)

It uses a high RPM motor and propeller, I do not think noise was a concern for them.

 

[EI-GYRO]

Thank you for the link, but;

Thank you for the link, but;

It didn't answer any of my points.

The video is of a Rotax-powered Cavalon, which proves they did have a video
camera.

Nowhere have I seen any evidence of a DEMONSTRATED 45-minute endurance.

I, too, admire your enthusiasm, but I fear that if you continue to ignore the
major issues, fiddling around the fine edges of the issue will get you nowhere.

There is a reason it is called HARDware.

Physics/gravity will not be outvoted by enthusiasm, or even pots of money.

And, for the record, noise reduction is a major issue, although perhaps only outside the U.S.

That is one of the main selling points behind the WattsUp. Noisy trainers grinding around the pattern is a major problem for the neighbors.

I know the electric machines are much quieter onboard, which is great, but the external perceived noise level is what counts.

 

[Hodag]

I posted the link before I saw your post, but later added the comments.

The Watts Up is now the Alpha Electro. It is loud inside but not outside. It also uses high RPM.

Many studies have been done and are being done on the effects of noise on animals above and below the water and noise and emissions are the main factors restricting use in reserve areas.

 

[EI-GYRO]

Oddly enough, Dr Tomazic said it is quiet enough inside to converse easily without headsets.
It will do what it says on the tin, I guess, but not more.

Part of the problem is the enthusiasts optimistically misinterpreting the technical statements of the developers. This was evident in the original article you linked to, and
the guy writing the article should have known better.

I like your proposed sig. Just put a smiley after it.

 

[Hodag]

I was just referencing this clip starting @ 4:40 (https://www.youtube.com/watch?v=WiADDbeFanU) (I'll leave the misinterpretations to others.)

But I agree, even high-RPM electric aircraft are much quieter overall than aircraft with reciprocating engines.

In what could become a contest to create the quietest rotorcraft for government contracts, it might be a mistake to not take advantage of the low-end torque of an electric motor and make the extra effort to create a direct drive system, especially since so few are doing it.

 

[birdy]

Bout noise and rotorcraft, the noisiest thing ona gyro, besides the passenger, is the prop.
Ona heli, the main rotor wen at low power settings, and the tail rotor wen you put your foot onit.
A 914 powered gyro or small heli is very quiet, cept for the blades.
So a silent lectric motor wont make the slightest difference.

A gyro or heli on a 914 will have bout 4 1/2 hours duration on 70L.
Cant see a 4 1/2 hour duration electric machine getn off the ground in my life time.

70L of petrol has xxx of energy avalable.
A battery with 4 1/2 hours will also need xxx energy, and where do you think this energy is comen from?

But, if you desigened silent blades, super long life and light batteries that will recharge to 100% in less than 5 mins off renewable energy supplies, youll be on a winner.