Yeah, that is scary. I will stick with 40 year old technology.
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thjakits
Well-Known Member
...I thought the 60km/h thing was relevant to the scaled MODEL!
As cblink and others pointed out - that speed range is not a "problem" for any existing rotor-design.
Contrary, you are not going to make anything useful (full-size) if you insist in wing-borne flight at these speeds, nor do you take advantage of rotor-borne flight....
As cblink said - study up and understand (...if not ask and have it explained until you do!) on everything that DOES exist and flies today - THEN start to explore improvements.
Whatever you try to accomplish - your design idea blatantly relies on known physics and principles - rotor and wing aerodynamics are explored/tested/understood to the very maximum possible within the limits of today's rotary and subsonic fixed wing flight (....no need to worry about supersonic and hypersonic studies and development - you won't use these in your design. Rotor aerodynamics do go into trans- and super-sonic regions, but very likely your design won't be affected by that - also that area is researched to the max...)
Presently - it seems to me - you are trying to invent a new system just because you can, not to actually solve a problem or improve on limits.
You name a number of "problems" which are actually not problems at all! Furthermore, with what we see from your design so far - with technology available today - you won't improve anything over the present systems with your stated operating parameters - that is - if you really look at a 60km/h transition from rotor to wing flight - simply because your design literally will out-weigh any perceived benefit over existing systems....
Your quote from the Horten brothers is a great inspiration - you might as well take up another principle they took very serious (and which Elon Musk very much embraces and emphasizes too) - "take away everything you do not need to make it work!" - The Horten brothers took that to the extreme and tested it - and later found that certain aspects were not beneficial and reverted to more traditional ways - e.g. pilot position in their Flying Wings - prone! No protruding canopy - aerodynamically perfect - however, a pilot needs to see and be able to work in the airframe! After a few great prone piloted sail-planes, pilots were sitting upright again!!
One other tip from my own experience in various fields - as a designer don't think you know it all, go out and talk to the people that will have to work on/in/with your design - mechanics! Go out and talk to the people that will have to fly your design - pilots! (unless you are going for autonomous flight from the start - that is coming anyway, but still, a pilot can tell you a lot about the behavior of these machines, what is present practice, what would be wished for to be improved...)
I already told you that a rotor below the fuselage will not work and the reasons for it - ask other professionals on this thread, and they certainly will repeat my assertion!
(This comes from experience too - I have 15k+ hours in the small helicopter utility field - you do NOT want a rotor under the fuselage! Even if you restrict your operations to hard surface only - there are ALWAYS FOs (Foreign Objects) around that can get picked up easily by a close to the ground rotor....)
You may not LIKE how present rotorcraft-technology looks or works, but it does so for a good reason.
Study and learn HOW and WHY a rotor works as it does on todays rotorcraft - then see IF you actually can improve on that!
Your design's different components have nothing (revolutionary) new - you only put existing principals together in a different configuration. The physics and dynamics of these components are well known and the technical solutions implemented are based on that. Certain principals can and are solved in different ways (in detail) but still address the basic underlying problem/solution - e.g. instead of 3 separate hinges you can implement a hinge-less design (as it is done!), but the principle need for 3xhinge function is still there!
In your design - as presented so far - you're using well researched and understood components - whether you can make these work together BETTER than they did in any other design before - that is what you seem to try to work out!
E.g. - you want retractable rotors - in principle a perfect thing to do - in practicality it is a technical nightmare - as many a design engineer realized in the past! I think you are still in the "primitive - basic idea"-phase and it seems incomprehensible that no one ever built this "simple" retract system!
Well, many tried! And I am certain they got to the point where it possibly could work - BUT at what cost??
Too heavy, to unreliable, too short a number of fatigue cycles, too much maintenance necessary...
As also mentioned above by others - often past concepts were just not practical for the technology available at some time and certainly can/should be revisited from time to time! (Your "friend" Igor Sikorsky was at that point too, when he invented the helicopter, but engines weren't there yet - and he had to wait another 15 years to get the power plant that would enable him to lift off! In the meantime he dedicated himself to design a number of magnificent Flying Boats!)
Here a very specific part of your design - just take one rotor and study up on it!!
You want a retractable/extendable rotor - figure out if you actually will be able to do that! IF you manage - THEN go on to the next problem - IF not - it doesn't make sense to continue with a theoretical technology that you cannot master in a efficient way and to a level that will work in your design. So - start there and calculate/design it into detail!
ALL existing rotor principals still apply to your design, so eventually you HAVE to learn and understand principals of rotorflight ANYWAY!! Learn which movements are required and how they are achieved today and THEN how you might be able to improve on that! Learn what kind of forces you are dealing with on your rotor - how you want to design your rotor, materials, stresses, fatigue cycles, flexing, resonances....
Once you understand at least at a basic level HOW a rotor works (the internal forces going through a rotor with every revolution) - AFTER THAT - it's time to think about HOW you possibly can make a retractable rotor-blade!
HOW will you support the retractable part in the non-retractable part? HOW will you actuate the retraction/extension?
IF with a cable-pulley system - are the pulleys able to work correctly under the acceleration-loads present? Can the cables be kept out of resonance frequencies? What happens if a cable breaks or a pulley seizes?
IF you plan on a jack-screw - how will you design the thread to avoid stress risers? Is the jack-screw also your rotor-spar? How heavy will that be?
Maybe hydraulics?
AFTER you find a viable solution to all that - NOW the mother of all problems - HOW will you SYNCHRONIZE ALL of the blades when retracting/extending?
Certainly a model is great place to physically implement and test concepts!
After the model - start calculating full-size numbers, often a model with work, but at full-size numbers do not work anymore - forces start to increase exponentially and rather sooner than later exceed available material parameters....
I wish you all the enlightenment possible for this task!
Enough said for today!
cheers,
thjakits
As cblink and others pointed out - that speed range is not a "problem" for any existing rotor-design.
Contrary, you are not going to make anything useful (full-size) if you insist in wing-borne flight at these speeds, nor do you take advantage of rotor-borne flight....
As cblink said - study up and understand (...if not ask and have it explained until you do!) on everything that DOES exist and flies today - THEN start to explore improvements.
Whatever you try to accomplish - your design idea blatantly relies on known physics and principles - rotor and wing aerodynamics are explored/tested/understood to the very maximum possible within the limits of today's rotary and subsonic fixed wing flight (....no need to worry about supersonic and hypersonic studies and development - you won't use these in your design. Rotor aerodynamics do go into trans- and super-sonic regions, but very likely your design won't be affected by that - also that area is researched to the max...)
Presently - it seems to me - you are trying to invent a new system just because you can, not to actually solve a problem or improve on limits.
You name a number of "problems" which are actually not problems at all! Furthermore, with what we see from your design so far - with technology available today - you won't improve anything over the present systems with your stated operating parameters - that is - if you really look at a 60km/h transition from rotor to wing flight - simply because your design literally will out-weigh any perceived benefit over existing systems....
Your quote from the Horten brothers is a great inspiration - you might as well take up another principle they took very serious (and which Elon Musk very much embraces and emphasizes too) - "take away everything you do not need to make it work!" - The Horten brothers took that to the extreme and tested it - and later found that certain aspects were not beneficial and reverted to more traditional ways - e.g. pilot position in their Flying Wings - prone! No protruding canopy - aerodynamically perfect - however, a pilot needs to see and be able to work in the airframe! After a few great prone piloted sail-planes, pilots were sitting upright again!!
One other tip from my own experience in various fields - as a designer don't think you know it all, go out and talk to the people that will have to work on/in/with your design - mechanics! Go out and talk to the people that will have to fly your design - pilots! (unless you are going for autonomous flight from the start - that is coming anyway, but still, a pilot can tell you a lot about the behavior of these machines, what is present practice, what would be wished for to be improved...)
I already told you that a rotor below the fuselage will not work and the reasons for it - ask other professionals on this thread, and they certainly will repeat my assertion!
(This comes from experience too - I have 15k+ hours in the small helicopter utility field - you do NOT want a rotor under the fuselage! Even if you restrict your operations to hard surface only - there are ALWAYS FOs (Foreign Objects) around that can get picked up easily by a close to the ground rotor....)
You may not LIKE how present rotorcraft-technology looks or works, but it does so for a good reason.
Study and learn HOW and WHY a rotor works as it does on todays rotorcraft - then see IF you actually can improve on that!
Your design's different components have nothing (revolutionary) new - you only put existing principals together in a different configuration. The physics and dynamics of these components are well known and the technical solutions implemented are based on that. Certain principals can and are solved in different ways (in detail) but still address the basic underlying problem/solution - e.g. instead of 3 separate hinges you can implement a hinge-less design (as it is done!), but the principle need for 3xhinge function is still there!
In your design - as presented so far - you're using well researched and understood components - whether you can make these work together BETTER than they did in any other design before - that is what you seem to try to work out!
E.g. - you want retractable rotors - in principle a perfect thing to do - in practicality it is a technical nightmare - as many a design engineer realized in the past! I think you are still in the "primitive - basic idea"-phase and it seems incomprehensible that no one ever built this "simple" retract system!
Well, many tried! And I am certain they got to the point where it possibly could work - BUT at what cost??
Too heavy, to unreliable, too short a number of fatigue cycles, too much maintenance necessary...
As also mentioned above by others - often past concepts were just not practical for the technology available at some time and certainly can/should be revisited from time to time! (Your "friend" Igor Sikorsky was at that point too, when he invented the helicopter, but engines weren't there yet - and he had to wait another 15 years to get the power plant that would enable him to lift off! In the meantime he dedicated himself to design a number of magnificent Flying Boats!)
Here a very specific part of your design - just take one rotor and study up on it!!
You want a retractable/extendable rotor - figure out if you actually will be able to do that! IF you manage - THEN go on to the next problem - IF not - it doesn't make sense to continue with a theoretical technology that you cannot master in a efficient way and to a level that will work in your design. So - start there and calculate/design it into detail!
ALL existing rotor principals still apply to your design, so eventually you HAVE to learn and understand principals of rotorflight ANYWAY!! Learn which movements are required and how they are achieved today and THEN how you might be able to improve on that! Learn what kind of forces you are dealing with on your rotor - how you want to design your rotor, materials, stresses, fatigue cycles, flexing, resonances....
Once you understand at least at a basic level HOW a rotor works (the internal forces going through a rotor with every revolution) - AFTER THAT - it's time to think about HOW you possibly can make a retractable rotor-blade!
HOW will you support the retractable part in the non-retractable part? HOW will you actuate the retraction/extension?
IF with a cable-pulley system - are the pulleys able to work correctly under the acceleration-loads present? Can the cables be kept out of resonance frequencies? What happens if a cable breaks or a pulley seizes?
IF you plan on a jack-screw - how will you design the thread to avoid stress risers? Is the jack-screw also your rotor-spar? How heavy will that be?
Maybe hydraulics?
AFTER you find a viable solution to all that - NOW the mother of all problems - HOW will you SYNCHRONIZE ALL of the blades when retracting/extending?
Certainly a model is great place to physically implement and test concepts!
After the model - start calculating full-size numbers, often a model with work, but at full-size numbers do not work anymore - forces start to increase exponentially and rather sooner than later exceed available material parameters....
I wish you all the enlightenment possible for this task!
Enough said for today!
cheers,
thjakits
Last edited:
dong090909 will need to move that rotor on the lower side of the fuselage before he can start down a path of credibility. It's somehow a
mandatory key in the success of his configuration, so I suppose he'll also continue the hunt for soft takeoff and landing clouds to support the fantasy.
mandatory key in the success of his configuration, so I suppose he'll also continue the hunt for soft takeoff and landing clouds to support the fantasy.
Dan Thomas
Well-Known Member
- Joined
- Sep 17, 2008
- Messages
- 6,982
No. Not my job to educate you. The internet has everything you need. Just go looking for it. When I was young, the only sources of information we had was a few magazines and whatever the local library happened to have, which was pretty much nothing.
Start with this textbook:
dong090909
Well-Known Member
Cblink & Thjakits:
Section1:
1. First of all, thank you so much for being so patient with your views,
2. I even think that today is the real start of the discussion
3. Therefore, I attach great importance to and rigorously clarify my thoughts, and then express them as much as possible
4. Let me summarize your content first:
A. This cruising speed scheme is meaningless
B. Look at what worked in the past, what worked at the moment, and what didn't work, and think about why
C. If there is a rigid rotor plan, the calculation results should be announced at the same time, and communicated with Sikorsky as much as possible;
D. The lift balance problem at the core of the rotor, resulting in the inevitable hinge (various forms)
E.S-97 vibration effects frighten pilots
F. This solution cannot solve the actual problem of the rotor now
G. The rotors under the fuselage must be removed
H. It is recommended to communicate with the pilot
I. The retractable rotor system is a terrible nightmare
Section2:
1. Now I officially start, starting with the most core:
One of the aerodynamic foundations of my aircraft is:
A.DONG090909 rotor conjecture, I think:
The number of blades is a cheap and efficient way to solve the lift balance of the rotor,
Even when the number of blades is large enough, there is no core problem of rotor lift balance, which is the core of the rotor system. From another point of view: the reason for this historical core problem is that the rotor has too few blades.
B. When there is no objection, I acquiesce that they are correct.
C. So, I tried my best to increase the number of blades. I must be the opposite of what you think of as great rotor history.
D. If you guys can prove my point wrong, I'll retract and review my design right away.
to be continued
Section1:
1. First of all, thank you so much for being so patient with your views,
2. I even think that today is the real start of the discussion
3. Therefore, I attach great importance to and rigorously clarify my thoughts, and then express them as much as possible
4. Let me summarize your content first:
A. This cruising speed scheme is meaningless
B. Look at what worked in the past, what worked at the moment, and what didn't work, and think about why
C. If there is a rigid rotor plan, the calculation results should be announced at the same time, and communicated with Sikorsky as much as possible;
D. The lift balance problem at the core of the rotor, resulting in the inevitable hinge (various forms)
E.S-97 vibration effects frighten pilots
F. This solution cannot solve the actual problem of the rotor now
G. The rotors under the fuselage must be removed
H. It is recommended to communicate with the pilot
I. The retractable rotor system is a terrible nightmare
Section2:
1. Now I officially start, starting with the most core:
One of the aerodynamic foundations of my aircraft is:
A.DONG090909 rotor conjecture, I think:
The number of blades is a cheap and efficient way to solve the lift balance of the rotor,
Even when the number of blades is large enough, there is no core problem of rotor lift balance, which is the core of the rotor system. From another point of view: the reason for this historical core problem is that the rotor has too few blades.
B. When there is no objection, I acquiesce that they are correct.
C. So, I tried my best to increase the number of blades. I must be the opposite of what you think of as great rotor history.
D. If you guys can prove my point wrong, I'll retract and review my design right away.
to be continued
dong090909
Well-Known Member
2. The second core issue: speed
A. With the vertical lift function, the method to achieve high speed
---The idea of the great man is to increase the speed of the rotor as much as possible
---My idea is: the rotor is only used for lifting, and the speed of the fixed wing is used to defeat the speed of the rotor
B. Because I have studied the history of the rotor, I think: great people make mistakes, their thinking is to make great problems and then solve them great.
C. So, I insist on making the rotor work at a low forward speed.
D. This means: fixed-wing high-speed flying aircraft, need to slow down the transition process, and then turn to rotor work.
E. There can be many tricks to this transition process, which I will focus on in the future, in addition to what I have mentioned before.
F. As a start, of course I want to avoid this transition process, so I start simple.
G. As for its meaning:
If it succeeds, it would monopolize the world's largest agricultural market and potentially bankrupt the world's largest airplane toy company.
A. With the vertical lift function, the method to achieve high speed
---The idea of the great man is to increase the speed of the rotor as much as possible
---My idea is: the rotor is only used for lifting, and the speed of the fixed wing is used to defeat the speed of the rotor
B. Because I have studied the history of the rotor, I think: great people make mistakes, their thinking is to make great problems and then solve them great.
C. So, I insist on making the rotor work at a low forward speed.
D. This means: fixed-wing high-speed flying aircraft, need to slow down the transition process, and then turn to rotor work.
E. There can be many tricks to this transition process, which I will focus on in the future, in addition to what I have mentioned before.
F. As a start, of course I want to avoid this transition process, so I start simple.
G. As for its meaning:
If it succeeds, it would monopolize the world's largest agricultural market and potentially bankrupt the world's largest airplane toy company.
Martin W
Well-Known Member
- Joined
- May 14, 2021
- Messages
- 209
NO ... NO .... NO .... and .... NO
A helicopter will fly just fine with just one blade (it has been done)
But it requires a heavy counterweight to balance everything
Might as well just add another blade instead of the counterweight (and that is what they do)
Remember that a spinning rotor acts like a round disc in the air .... more blades or less blades do not change that.
3 or more blades do have many advantages .... shorter blades can be used and they make less noise ... etc
Study the 1968 Bell 212 .... two huge blades .... about 3 feet wide .... WOP WOP WOP sound (Viet Nam era) ... max speed about 140 mph
Modern Bell 412 is pretty much the same machine with 4 blades and other updates .... max speed about 160 mph .... not much faster but quieter..
dong090909 .... your problem is you dont know what you dont know .
Spend more time studying helicopters
Then start inventing.
.
dong090909
Well-Known Member
3. The third core issue: collection, Embeded rotor oriented craft
A. Since no one questioned: efficiency, weight, strength, drive, power supply of diamond jacks. . . . . . I take them as feasible.
They are without a doubt the most important breakthroughs in aircraft design for embeded rotor oriented craft, in terms of structure.
B. Next, the way of collecting will naturally take into account the lift rotor shaft, and I did the same back then.
C. Later, I found out: In the initial stage, there are at least N solutions, which are easier to implement than the lifting shaft. For example the following:
D. Then, I thought: the purpose of collection is to reduce the drag caused by the rotor when the fixed wing is flying, and at a speed of 60 kilometers per hour, the rotor has been harvested in a straight line, how much is the wind resistance?
E. I would like to ask university professors for help, but they are worried that my political theories will affect them.
F. So I want to gamble with the convertible, this cheapest wind tunnel:
--- Try it out first,
---If the result is not ideal, I will consider partial packaging,
---Partial packaging is not ideal, I will pack it in full,
---The jack can also be ducted to expose the longest screw
to be continued
A. Since no one questioned: efficiency, weight, strength, drive, power supply of diamond jacks. . . . . . I take them as feasible.
They are without a doubt the most important breakthroughs in aircraft design for embeded rotor oriented craft, in terms of structure.
B. Next, the way of collecting will naturally take into account the lift rotor shaft, and I did the same back then.
C. Later, I found out: In the initial stage, there are at least N solutions, which are easier to implement than the lifting shaft. For example the following:
D. Then, I thought: the purpose of collection is to reduce the drag caused by the rotor when the fixed wing is flying, and at a speed of 60 kilometers per hour, the rotor has been harvested in a straight line, how much is the wind resistance?
E. I would like to ask university professors for help, but they are worried that my political theories will affect them.
F. So I want to gamble with the convertible, this cheapest wind tunnel:
--- Try it out first,
---If the result is not ideal, I will consider partial packaging,
---Partial packaging is not ideal, I will pack it in full,
---The jack can also be ducted to expose the longest screw
to be continued
Attachments
dong090909
Well-Known Member
Although you've obviously gone in circles and didn't answer my most central question, I don't want to simply dismiss you.
I'll put your question aside for now, I'll have to focus my energy on answering Cblink & Thjakits .
Step by step.
dong090909
Well-Known Member
4. The fourth core problem: the rotor under the fuselage
A. This is undoubtedly the most alternative and most questioned.
B. The only reason is: the traditional dual rotors on the fuselage, I can not collect.
C. Putting it under the fuselage, although there are indeed many drawbacks, but at least I can achieve the goal. Compared with the new problem that cannot be achieved, I choose the new problem.
D. Also, I already have multiple options to reduce the impact of new problems (discussed later). I also believe that Sikorsky will have a very short time to solve this problem compared to more than half a century to come up with the first rigid rotor.
E. Remarks:
I really learned from the flying saucer: the rotor is placed under the fuselage.
When the number of rotor blades up and down the fuselage is infinite, it is essentially a flying saucer.
A. This is undoubtedly the most alternative and most questioned.
B. The only reason is: the traditional dual rotors on the fuselage, I can not collect.
C. Putting it under the fuselage, although there are indeed many drawbacks, but at least I can achieve the goal. Compared with the new problem that cannot be achieved, I choose the new problem.
D. Also, I already have multiple options to reduce the impact of new problems (discussed later). I also believe that Sikorsky will have a very short time to solve this problem compared to more than half a century to come up with the first rigid rotor.
E. Remarks:
I really learned from the flying saucer: the rotor is placed under the fuselage.
When the number of rotor blades up and down the fuselage is infinite, it is essentially a flying saucer.
dong090909
Well-Known Member
COMMENT:
This cruising speed scheme is meaningless
---Refer to the previous content
B. Look at what worked in the past, what worked at the moment, and what didn't work, and think about why
---I have been donging
C. If there is a rigid rotor plan, the calculation results should be announced at the same time, and communicated with Sikorsky as much as possible;
----After reviewed by the world, I will employ engineer to CFD.
By the way, how to contact Sikorsky.
D. The lift balance problem at the core of the rotor, resulting in the inevitable hinge (various forms)
---Let world approved.
E.S-97 vibration effects frighten pilots
---Decrease speed.
F. This solution cannot solve the actual problem of the rotor now
---Let world approved.
G. The rotors under the fuselage must be removed
---Suspension,maybe fucture ok.
H. It is recommended to communicate with the pilot
---Good idea, I try my best.
I. The retractable rotor system is a terrible nightmare
---Suspension, at least it isn‘t the critical issue.
End
Thanks.
This cruising speed scheme is meaningless
---Refer to the previous content
B. Look at what worked in the past, what worked at the moment, and what didn't work, and think about why
---I have been donging
C. If there is a rigid rotor plan, the calculation results should be announced at the same time, and communicated with Sikorsky as much as possible;
----After reviewed by the world, I will employ engineer to CFD.
By the way, how to contact Sikorsky.
D. The lift balance problem at the core of the rotor, resulting in the inevitable hinge (various forms)
---Let world approved.
E.S-97 vibration effects frighten pilots
---Decrease speed.
F. This solution cannot solve the actual problem of the rotor now
---Let world approved.
G. The rotors under the fuselage must be removed
---Suspension,maybe fucture ok.
H. It is recommended to communicate with the pilot
---Good idea, I try my best.
I. The retractable rotor system is a terrible nightmare
---Suspension, at least it isn‘t the critical issue.
End
Thanks.
dong090909
Well-Known Member
Now, let me answer your question.
1. In fact, we have warmed up many times.
2. I also said: we are not talking about the same question: I hope you attack the core: A, and you said B.
3. Now I change the angle, from a logical point of view this question:
A. Despite my poor knowledge of flexible rotors, I understand that your statement about flexible rotors is correct based on history.
Logic:
---To solve the core problem of rotor lift balance,
---Solved within the scope of the flexible rotor
Only by compounding these 2 conditions, your statement will make sense.
B. Unfortunately: from more than ten years ago, I thought: I use rigid better than flexible, so I almost ignored the essence of flexible rotor.
C. I can achieve my goal, why I must use it: the conditions and factors that a flexible rotor must have
4. I do have poor knowledge and I have been learning. But even if I have the level of Rukovsky now, I will communicate with you in this logic: please deny my conjecture first.
5. I reiterate that I dare to compete with Sikorsky, Boeing, Martin…… because of my battle-tested creativity.
To make it easier to explain, you directly treat me as the second Sikorsky:
Without the theoretical level of Rukovsky,
But dare to challenge authority, dare to innovate, and always act.
6. Perhaps the biggest difference between me and Sikorsky is that I have not made up my mind to go to the United States to make aircraft because of political treatment.
7.Don‘t take It mind, just a joke
Martin W
Well-Known Member
- Joined
- May 14, 2021
- Messages
- 209
.
dong090909
From the beginning you have nothing good to say about Sikorsky
You pretend to be better than them with your cardboard tube , sticks , and glue gun..
Here is what Sikorsky was doing in 1948
Speed record 129.6 mph
First helicopter to perform a loop.
You were not even born yet
Your father was not even born yet.
dong090909
From the beginning you have nothing good to say about Sikorsky
You pretend to be better than them with your cardboard tube , sticks , and glue gun..
Here is what Sikorsky was doing in 1948
Speed record 129.6 mph
First helicopter to perform a loop.
You were not even born yet
Your father was not even born yet.
thjakits
Well-Known Member
Dong09,
I am too tired at this time to answer - again - your various and some of these very erroneous assumptions - I'll see if I have some time and patience tomorrow...
At this stage I only can assume (....and actually hope) that most of what comes through in your posts is really just a difficult translator!!
Your posts seem to indicate, that you have absolutely NO understanding - not even basics - of powered rotor flight.
You seem not to listen at all, what accomplished professionals are suggesting to you!
Most of your arguments make no sense - you try to correct non-existing problems by inventing REAL problems!!
Just a very quick observation:
You think you can solve dissymmetry of lift and the required and proven solutions just by increasing the number of rotor-blades!! My friend, a helicopter rotor is NOT a fan!! To be able to control a powered rotor you need to really study how a rotor works! It doesn't matter if you use a 2-blade rotor or a 8-blade rotor - still, every blade goes through the same motion on every revolution of the rotor!! You cannot do away with rotor control just by increasing the number of blades and slowing the overall possible forward speed - it does not work like that!
Your fantasy speed of 60 km/h will not work as a transition speed - you are not in airplane territory there - you are in slow ultra-light territory!!
[Actually - you COULD make it work at 60 - with FANS!! NO rotors, just fans! You will need a LOT of power and control surfaces for the fan flow - THAT could possibly work if you are careful with the design - it will be very inefficient compared to a rotor, but if you limit your vertical powered flight regime to that stated by you - you very likely would be successful with a multiple ducted fan design for the vertical flight part! Look up the "Moeller Flying Car" and ....about every Electric Vertical Take-off and Landing Vehicle dreamed up so far!]
Back to REAL rotors:
You CANNOT increase your blade number into infinity and pretend a solid disc - saucer - UFO will still work like a rotor system!! You seem to have NO understanding of aerodynamic flow over an airfoil/rotor - eventually you will have flow from a rotor influence the flow of the next rotor ( and usually in a bad way!).
When you go infinity/solid - there is no more flow over rotor blades - there is only flow over a solid disc - which has absolutely NOTHING to do with aerodynamics over a rotor!
For a powered rotor to work you need to control it! A light gyroplane rotor is NOT a powered rotor - it is a fixed pitch windmill - it is at a fixed speed - a permanently autorotating system - most are a crude - essentially - weight-shift affair! A more sophisticated system would still require a fully controllable rotor (like the Air&Space 18A).
According to your plans you have TWO fully powered rotors!!
Before you even think about diving into the above mentioned MECHANICS book about helicopters - learn how a conventional helicopter works - get yourself ANY book that has these words in the title: "Principals of rotor flight" or "Principals of helicopter flight" here is one example: Amazon.com
When you have actually read, learned and understood the presently in production an working fairly flawless classic/traditional rotor system of presently perfectly working helicopters - THEN come back and start discussing any plans you still might have to revolutionize powered rotor flight!!
What you are presently arguing is close to nonsense - your arguments that will lead Sikorsky (and presumably every other rotorcraft powerhouse) into bankruptcy shortly have absolutely no reason or substance in the rotorcraft industry. Learn what is possible with the present rotor systems before you argue their flaws ...and worse - invent problems that do not exist and only can be remedied by your "solutions" that are actually worse problems than you seem to see!!
Again - I hope that most misunderstandings here are a translation problem and not your actual arguments!!
Do yourself a favor and try to study up actual helicopter flight principals and understand them - that alone will do away with most of your misconceptions and as a result will severely change your design!!
If you cannot access the above mentioned book or similar:
I don't know if you can access these sites in China but here are a few just to get you started!
science.howstuffworks.com
www.explainthatstuff.com
barossahelicopters.com.au
here a search - query on youtube:
As I said - I have NO idea if you are able to access these sites from China, if you can - search for any basic term of a helicopter and you will find something to study about it!
I am pretty sure China has it's own version of educational internet. Principals of helicopter flight are no secret.
You should be able to access ALL the information you need to learn the basic things about helicopter flight!
Learn and understand what is working today!! Only then you can try to improve or revolutionize Rotor-flight!!
The problems you state are NOT REAL!!
I hope you understand this post after translating it!
Dong09 - DO as was suggested to you by various people above (incl. myself) - STUDY what was suggested and THEN come back and discuss again...
Just repeating your misguided assumptions and dismissing professional suggestions will thin your audience to zero in a very short time....
We all love to discuss aviation on here and the more extreme it gets the more exciting for all!
We all love to help out and introduce new people that are enthusiastic about aviation!
We all share experience willingly and free of charge!
WE do NOT hang around very long for useless arguments....
Good luck Dong09!!
thjakits
I am too tired at this time to answer - again - your various and some of these very erroneous assumptions - I'll see if I have some time and patience tomorrow...
At this stage I only can assume (....and actually hope) that most of what comes through in your posts is really just a difficult translator!!
Your posts seem to indicate, that you have absolutely NO understanding - not even basics - of powered rotor flight.
You seem not to listen at all, what accomplished professionals are suggesting to you!
Most of your arguments make no sense - you try to correct non-existing problems by inventing REAL problems!!
Just a very quick observation:
You think you can solve dissymmetry of lift and the required and proven solutions just by increasing the number of rotor-blades!! My friend, a helicopter rotor is NOT a fan!! To be able to control a powered rotor you need to really study how a rotor works! It doesn't matter if you use a 2-blade rotor or a 8-blade rotor - still, every blade goes through the same motion on every revolution of the rotor!! You cannot do away with rotor control just by increasing the number of blades and slowing the overall possible forward speed - it does not work like that!
Your fantasy speed of 60 km/h will not work as a transition speed - you are not in airplane territory there - you are in slow ultra-light territory!!
[Actually - you COULD make it work at 60 - with FANS!! NO rotors, just fans! You will need a LOT of power and control surfaces for the fan flow - THAT could possibly work if you are careful with the design - it will be very inefficient compared to a rotor, but if you limit your vertical powered flight regime to that stated by you - you very likely would be successful with a multiple ducted fan design for the vertical flight part! Look up the "Moeller Flying Car" and ....about every Electric Vertical Take-off and Landing Vehicle dreamed up so far!]
Back to REAL rotors:
You CANNOT increase your blade number into infinity and pretend a solid disc - saucer - UFO will still work like a rotor system!! You seem to have NO understanding of aerodynamic flow over an airfoil/rotor - eventually you will have flow from a rotor influence the flow of the next rotor ( and usually in a bad way!).
When you go infinity/solid - there is no more flow over rotor blades - there is only flow over a solid disc - which has absolutely NOTHING to do with aerodynamics over a rotor!
For a powered rotor to work you need to control it! A light gyroplane rotor is NOT a powered rotor - it is a fixed pitch windmill - it is at a fixed speed - a permanently autorotating system - most are a crude - essentially - weight-shift affair! A more sophisticated system would still require a fully controllable rotor (like the Air&Space 18A).
According to your plans you have TWO fully powered rotors!!
Before you even think about diving into the above mentioned MECHANICS book about helicopters - learn how a conventional helicopter works - get yourself ANY book that has these words in the title: "Principals of rotor flight" or "Principals of helicopter flight" here is one example: Amazon.com
When you have actually read, learned and understood the presently in production an working fairly flawless classic/traditional rotor system of presently perfectly working helicopters - THEN come back and start discussing any plans you still might have to revolutionize powered rotor flight!!
What you are presently arguing is close to nonsense - your arguments that will lead Sikorsky (and presumably every other rotorcraft powerhouse) into bankruptcy shortly have absolutely no reason or substance in the rotorcraft industry. Learn what is possible with the present rotor systems before you argue their flaws ...and worse - invent problems that do not exist and only can be remedied by your "solutions" that are actually worse problems than you seem to see!!
Again - I hope that most misunderstandings here are a translation problem and not your actual arguments!!
Do yourself a favor and try to study up actual helicopter flight principals and understand them - that alone will do away with most of your misconceptions and as a result will severely change your design!!
If you cannot access the above mentioned book or similar:
I don't know if you can access these sites in China but here are a few just to get you started!
How Helicopters Work
Believe it or not, the marvel we know as the helicopter began as a Chinese top consisting of a shaft — a stick — adorned with feathers on one end.
science.howstuffworks.com
How does a helicopter work? | Who invented helicopters?
A simple introduction to how helicopters stay airborne and steer.
How do Helicopters Fly? • Barossa Helicopters -
barossahelicopters.com.au
here a search - query on youtube:
As I said - I have NO idea if you are able to access these sites from China, if you can - search for any basic term of a helicopter and you will find something to study about it!
I am pretty sure China has it's own version of educational internet. Principals of helicopter flight are no secret.
You should be able to access ALL the information you need to learn the basic things about helicopter flight!
Learn and understand what is working today!! Only then you can try to improve or revolutionize Rotor-flight!!
The problems you state are NOT REAL!!
I hope you understand this post after translating it!
Dong09 - DO as was suggested to you by various people above (incl. myself) - STUDY what was suggested and THEN come back and discuss again...
Just repeating your misguided assumptions and dismissing professional suggestions will thin your audience to zero in a very short time....
We all love to discuss aviation on here and the more extreme it gets the more exciting for all!
We all love to help out and introduce new people that are enthusiastic about aviation!
We all share experience willingly and free of charge!
WE do NOT hang around very long for useless arguments....
Good luck Dong09!!
thjakits
dong090909
Well-Known Member
Perhaps, now is the time to embody your philosophy: put aside the tediousness and use the most direct and simple method.Dong09,
I am too tired at this time to answer - again - your various and some of these very erroneous assumptions - I'll see if I have some time and patience tomorrow...
At this stage I only can assume (....and actually hope) that most of what comes through in your posts is really just a difficult translator!!
Your posts seem to indicate, that you have absolutely NO understanding - not even basics - of powered rotor flight.
You seem not to listen at all, what accomplished professionals are suggesting to you!
Most of your arguments make no sense - you try to correct non-existing problems by inventing REAL problems!!
Just a very quick observation:
You think you can solve dissymmetry of lift and the required and proven solutions just by increasing the number of rotor-blades!! My friend, a helicopter rotor is NOT a fan!! To be able to control a powered rotor you need to really study how a rotor works! It doesn't matter if you use a 2-blade rotor or a 8-blade rotor - still, every blade goes through the same motion on every revolution of the rotor!! You cannot do away with rotor control just by increasing the number of blades and slowing the overall possible forward speed - it does not work like that!
Your fantasy speed of 60 km/h will not work as a transition speed - you are not in airplane territory there - you are in slow ultra-light territory!!
[Actually - you COULD make it work at 60 - with FANS!! NO rotors, just fans! You will need a LOT of power and control surfaces for the fan flow - THAT could possibly work if you are careful with the design - it will be very inefficient compared to a rotor, but if you limit your vertical powered flight regime to that stated by you - you very likely would be successful with a multiple ducted fan design for the vertical flight part! Look up the "Moeller Flying Car" and ....about every Electric Vertical Take-off and Landing Vehicle dreamed up so far!]
Back to REAL rotors:
You CANNOT increase your blade number into infinity and pretend a solid disc - saucer - UFO will still work like a rotor system!! You seem to have NO understanding of aerodynamic flow over an airfoil/rotor - eventually you will have flow from a rotor influence the flow of the next rotor ( and usually in a bad way!).
When you go infinity/solid - there is no more flow over rotor blades - there is only flow over a solid disc - which has absolutely NOTHING to do with aerodynamics over a rotor!
For a powered rotor to work you need to control it! A light gyroplane rotor is NOT a powered rotor - it is a fixed pitch windmill - it is at a fixed speed - a permanently autorotating system - most are a crude - essentially - weight-shift affair! A more sophisticated system would still require a fully controllable rotor (like the Air&Space 18A).
According to your plans you have TWO fully powered rotors!!
Before you even think about diving into the above mentioned MECHANICS book about helicopters - learn how a conventional helicopter works - get yourself ANY book that has these words in the title: "Principals of rotor flight" or "Principals of helicopter flight" here is one example: Amazon.com
When you have actually read, learned and understood the presently in production an working fairly flawless classic/traditional rotor system of presently perfectly working helicopters - THEN come back and start discussing any plans you still might have to revolutionize powered rotor flight!!
What you are presently arguing is close to nonsense - your arguments that will lead Sikorsky (and presumably every other rotorcraft powerhouse) into bankruptcy shortly have absolutely no reason or substance in the rotorcraft industry. Learn what is possible with the present rotor systems before you argue their flaws ...and worse - invent problems that do not exist and only can be remedied by your "solutions" that are actually worse problems than you seem to see!!
Again - I hope that most misunderstandings here are a translation problem and not your actual arguments!!
Do yourself a favor and try to study up actual helicopter flight principals and understand them - that alone will do away with most of your misconceptions and as a result will severely change your design!!
If you cannot access the above mentioned book or similar:
I don't know if you can access these sites in China but here are a few just to get you started!
How Helicopters Work
Believe it or not, the marvel we know as the helicopter began as a Chinese top consisting of a shaft — a stick — adorned with feathers on one end.
How does a helicopter work? | Who invented helicopters?
A simple introduction to how helicopters stay airborne and steer.
How do Helicopters Fly? • Barossa Helicopters -
here a search - query on youtube:
As I said - I have NO idea if you are able to access these sites from China, if you can - search for any basic term of a helicopter and you will find something to study about it!
I am pretty sure China has it's own version of educational internet. Principals of helicopter flight are no secret.
You should be able to access ALL the information you need to learn the basic things about helicopter flight!
Learn and understand what is working today!! Only then you can try to improve or revolutionize Rotor-flight!!
The problems you state are NOT REAL!!
I hope you understand this post after translating it!
Dong09 - DO as was suggested to you by various people above (incl. myself) - STUDY what was suggested and THEN come back and discuss again...
Just repeating your misguided assumptions and dismissing professional suggestions will thin your audience to zero in a very short time....
We all love to discuss aviation on here and the more extreme it gets the more exciting for all!
We all love to help out and introduce new people that are enthusiastic about aviation!
We all share experience willingly and free of charge!
WE do NOT hang around very long for useless arguments....
Good luck Dong09!!
thjakits
Please directly deny my conjecture.
dong090909
Well-Known Member
I have countless examples to sing Sikorsky, but I don't have the time. Because, I am now really improving on the flaws of this great company.
I don't need to cover up hypocritically.
As a tilt-rotor pilot, as has @thjakits has suggested, you are aiming to solve what you perceive as a critical problem. This is great! However, you do not understand the fundamental principles, as you are presenting a solution that makes no sense to any of us; as it creates problems that have been long-since solved.
It is okay. I have been there before. When I was very young, I thought I had the answers to everything...but then I had to learn things such as physics, aerodynamics, flying qualities and the massive mathematics behind all of it.
Although we greatly appreciate what you are aiming to do, you have much to learn, as it seems apparent you do not have an engineering-type background. It will take time, but I can assure you it is achievable!
I am both and engineer and a pilot, working in the world of developmental flight testing. There are some ethical rules we absolutely live by:
1. Keep it simple to the furthest extent possible
2. Work the problem; do not fight it
3. No problem has ever been effectively solved by guessing & conjecture. Ever.
4. Nobody knows everything about anything. This is why we work in teams.
5. Set realistic goals
6. Know that you will have setbacks
7. Necessity drives innovation
8. Never bash the competition or any received criticism; all it does is tarnish YOUR reputation
9. Manage expectations
10. Celebrate your successes, but own your failures
We are endeavoring to educate you. For free. At no cost to you. Take advantage of it...because we want you to succeed. While we cannot provide you with everything you need to know, we will gladly point you in the right direction, for this is a journey that will require some individual effort on your part.
It is okay to ask questions; we implore you to do so.
You claim that what you are aiming to do is to create some kind of aircraft for an agricultural application. You may be better served pursuing a purely rotary wing solution. Again, as I have stated before, when you embark on an aircraft design project, ask yourself the following questions:
1. What am I trying to do?
2. What is the mission of the aircraft?
3. How fast do I need to go?
4. How slow do I need to go?
5. How far do I need to go?
6. How much do I need to carry?
7. How high do I need to fly?
8. What do I have to work with? (ie, resources, physical & financial constraints)
9. Has this mission been accomplished before? What worked, and what didn't...and why?
10. Has my idea been tried before in some way? If it has and was not successful, why?
Aircraft design is a series of iterations of innovation & compromise. It is not easy, this coming from someone who is currently developing his own homebuilt. You need to be realistic in what you are trying to do.
For example, if you are wanting to carry six people, taking off from a runway up at 3000m density altitude on a hot summer day in less than 200m, travel supersonically 5000km to your destination, but only have carbon fiber tubing, sail fabric and a Rotax 582 engine at your disposal, then you need to accept that you cannot solve this problem, as the physical constraints prohibit it. A lightweight carbon tube frame covered in fabric cannot take the forces applied to it at supersonic speeds, and even if it did, a little 2-stroke Rotax 582 has nowhere enough power to get you into that regime, let alone enough power to do anything else you wish to do.
However, if you desire to create a single-seat ultralight, then that tubing, fabric and that Rotax 582 will be ideal. Why? Because that carbon tubing can be made into a lightweight structure that can handle the structural loads seen in ultralight flight and the fabric can be applied to create the aerodynamic shape you need...and the Rotax 582 offers enough power to get you in the air. Make sense?
If you want to look at something neat...I want you to look at this idea whose time has possibly come:
Bell's Plan To Finally Realize A Rotorcraft That Flies Like A Jet But Hovers Like A Helicopter
After 50 years of sporadic development, Bell thinks it can build a survivable, long-range, high-speed, VTOL aircraft adapted to tomorrow's wars.
www.thedrive.com
Last edited:
TFF
Well-Known Member
You cannot wish something to work. 100 years ago early helicopter inventors were trying to gather data for their ideas to make work. The successful were not guessing but working the problem. Only when knowledge and materials met did they become successful.
Wishing away reality does not work for anything. You can Elizabeth Holmes it, where you can be so convincing that bunches of people will give you money, but you don’t have a clue about anything and you hope you find a solution. She was copying Steve Jobs who did dream of new ways to package what was already doable. Elon Musk is only repackaging what people have already invented.
When you say you want some element a certain way, it seems you are trying to decree it like a king. Black shall be white and white shall be black. Order to enforce order. When someone is telling you it will not work because of known physics, you can’t answer I will get some engineer to CFD it. The only answer to break convention is to give us the engineering answer. We gave you an engineering answer and would like one in return.
You do not have to be an engineer to give an engineer answer. Plenty of smarter people know more than schooled people. You can not answer the question, because I want it that way. We only want to know why it can be that way. That is what the exchange is here. Discussion of why and why not things will work, not video game physics where you can be central leader and order the world to be like it should be to your liking. Copying management at Boeing is the wrong thing to do.
Wishing away reality does not work for anything. You can Elizabeth Holmes it, where you can be so convincing that bunches of people will give you money, but you don’t have a clue about anything and you hope you find a solution. She was copying Steve Jobs who did dream of new ways to package what was already doable. Elon Musk is only repackaging what people have already invented.
When you say you want some element a certain way, it seems you are trying to decree it like a king. Black shall be white and white shall be black. Order to enforce order. When someone is telling you it will not work because of known physics, you can’t answer I will get some engineer to CFD it. The only answer to break convention is to give us the engineering answer. We gave you an engineering answer and would like one in return.
You do not have to be an engineer to give an engineer answer. Plenty of smarter people know more than schooled people. You can not answer the question, because I want it that way. We only want to know why it can be that way. That is what the exchange is here. Discussion of why and why not things will work, not video game physics where you can be central leader and order the world to be like it should be to your liking. Copying management at Boeing is the wrong thing to do.
To build a Flying Saucer make an actuator disc.
Dan Thomas
Well-Known Member
- Joined
- Sep 17, 2008
- Messages
- 6,982
That book covers all the principles of flight of the various helicopter configurations, then it gets into the details of the systems. It's much more than just how to maintain a helicopter. Mechanics are expected to know all of it, and they usually know a lot more about the machine and how it works than the pilot does.
- Status
