Thank you very much for your patience, I see your kindness in it.VTOL history is long and full of imaginative aircraft concepts that even on paper failed, concepts that went to prototyping and failed. Most of these aircraft are represented in the famous - VTOL wheel of mis-fortune published by vertical flight society. From hundreds of configurations only 3 types actually succeeded:
- the classical helicopter - the best hovering performance due to low disk loading, but it's cruise performance is lacking due to low L/D, and has limited speed due to retreating blade stall.
- Tilt wing/rotor - a compromise between hovering and cruise performance
- Jet VTOL configuration - representative harrier and F35
The last two are military aircraft, and the military specification aspect to perform the mission are the reason of their success, the economic cost being secondary, and the real reason why you don't see a tilt rotor in commercial service despite more than 20 years of AW609 development.
Some people think that electric propulsion offer advantages to bring some VTOL configuration to commercial success, and for good reasons, like high inherent efficiency, distributed propulsion and other effects, but a hidden aspect that kills the high efficiency of electric propulsion is the aerodynamics of VTOL. If the aerodynamics is not right, you end up with an inefficient aircraft, that only exacerbates the unwanted characteristics of electric propulsion - the weight and low specific energy of current batteries that for now cannot compete with fuel as a source of energy especially for longer flights.
You see, there is a problem that isn't solved yet for VTOL designs and that is making an aircraft capable of vertical takeoff and landing, having good hovering performance, but still having high cruise performance and economy. This distils to conflicting requirements for the driving parameters of cruise and hovering performance: L/D drives the performance in cruise and that means large aspect ratio wings, low wetted area and small propeller size. Disk loading and no flow interference drives the hovering performance and that means large rotors and no wings.
All VTOL configurations of today are lacking one aspect or another, there are compromises driving performance for hover or cruise, or more likely both, to be lower than what is commercially viable.
Designing an aircraft needs discipline and a fundamental knowledge of physical laws, especially aerodynamics and aeronautics, the physical laws don't really care of who are you and that you 'beat millions of people' - I guess this is a language issue - I assume the meaning is you are the best in millions?
The stories told on this forum are not meaningless - if you cannot find the meaning - your loss. If you don't want to waste your time, I suggest to start from some good aerodynamic and aircraft design books. Learn why most aircraft have long slender wings and why helicopters have large rotors.
Why do your aircraft have coaxial rotors? If for swirl recovery - it is totally meaningless. The weight and complications of the second rotor largely surpass any benefit for swirl recovery. If for anti-torque, there are better ways, especially as you have propellers. You also mentioned coaxial propellers - why? You also mentioned wings. How do you account for the destructive interference in hover, fountain lift and impingement? As I understand your concept is lift + cruise configuration, you have separate lift and cruise systems, the killer of this configuration is weight - you always have a system that is 'dead weight' not contributing to performance, but taking expensive cargo or fuel weight, how do you manage the weight increase? Do some preliminary calculations and show us how your design would perform in hover and cruise. A lot of good VTOL concepts and prototypes were 'killed' by transition performance, so keep an eye on that as well.
Once a very intelligent man said: 'Those who do not learn history are doomed to repeat it.' I think this is a very good motto for the vanabee VTOL aircraft designers of today.
I feel your motherland is China for your logicA great part of your problem here is inability to communicate your ideas.
Such as, "suppress rotor lift fluctuations with fixed wings"; post a sketch that illustrates your concept. No one here knows.
Then, and this is especially necessary, the "the side-flying gyro effect". The model you show gives us no hint. Post a sketch of the concept. Add numbers if possible (rpm, moments of inertia, precession forces and moments, and so on). No one here is likely to steal your ideas.
Anyone can draw and yak about air vehicles with 10 kg 200kW engines and tiny wings with complex high lift devices that produce lift coefficients of 20, all in 50 kg airframes that cost the price of a 12 pack of beer that can be built under a shade tree in a couple of afternoons from materials bought at Walmart, that occurs here at least weekly. Imagination flies, physics, and especially gravity, has the last say.
If you are not able to explain how your concept functions, then you cannot produce an analysis that gives the idea credibility. Understanding your own idea is fundamental, and a tiny bit of analysis will give you insight into its viability.I feel your motherland is China for your logic
Thank you for your pertinent point .Moderator Note: Let's all take a deep breath and step back a moment. This has turned into a snarking match.
dong090909: If you have specific questions, ask them. Listen to the answers and consider them. There are some extremely knowledgeable people here. In the long run, the best way you can prove your ideas is through calculation, a flying model, or a prototype. Simply saying that they'll work or are revolutionary isn't constructive discussion.
Everyone else: You're skeptical. You're sure this isn't going to work. Okay, not unreasonable. We've seen plenty of 'out there' ideas here on HBA. Try and help the guy learn. Provide specific answers to specific questions. Point him at reasources. Share your knowledge. Simply being one of thirty people telling him, "Your ideas won't work, it's stupid," isn't helping anyone here. Everyone here started at zero. Help them get to one. If they won't accept your help, walk away. Beating on them doesn't do anyone any good.
Advanced autogyros approach the complication of helicopters, require lots of power, they are slow, and cost too much for their utility.Good machine but nobody wanted to buy them .... same as the Mculloch J2 and Air and Space 18-A .... all gone now
No need to wonder. If it doesn't perform as the company hoped it would and the customers were told it would perform eventually the truth is learned. Efficiency and performance matter.I wonder why this project has been not succesfull...
It was technically interesting, test flown and certified solution.
OK, thanks.Same with the B 747 SP.
No need to wonder. If it doesn't perform as the company hoped it would and the customers were told it would perform eventually the truth is learned. Efficiency and performance matter.
Yip, and the sad thing is that each and every one of those designers/builders thought their particular machine is going to revolutionise air travel.This video covers the topic; counter rotating rotors and props, ornithopters, threshing machines, egg beaters, and flaming butts -
This one covers most of the same ground and adds the flapping vane parasol -
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