revoutionary new design --only

HomeBuiltAirplanes.com

Help Support HomeBuiltAirplanes.com:

Aircar

Banned
Joined
Feb 20, 2010
Messages
3,567
Location
Melbourne Australia
I have noted previously that the overall heading of this section of HBA is mostly honoured in the breach viz. "emerging new technology that might revolutionize our sport " -in practice most of the threads in this section are not about anything remotely 'revolutionary' so I thought that a SPECIFIC thread (with links to those posts or other threads that are potentially 'revolutionary' might be of value and isolate from the 'how to' material.

Maybe a definition of what is considered 'revolutionary' should be the starting point.- not having a dictionary handy I would venture to include those things that might RADICALLY lower the cost of flight (dollars and man hours together ) that might bring flight within reach of many many more people than now (in the literal and metaphorical senses) that employ new scientific principles (eg Henryk's vortex lift theory of his colleagues or the single line power transmission)
that might expand the flight envelope enough to give more capabilities (more speed is unlikely to do much for anything but very much LESS (minimum speed) might open up new opportunities for operation outside of airports for example , new powerplants and fuels,new materials or processes, new aerodynamic devices and any sort of innovation that yields something that opens new threshold as examples. Defining what the barriers are also defines the breakthroughs of those barriers--so the desiradata must come first.

But MOSTLY this thread should be NOTHING BUT truly revolutionary inovations or advances and steer away from shop issues or
how to' in the fabricate or analysis sense --maybe it is best encapsulated as the 'synthesis' thread rather than analysis. "what to" rather than 'how to'

Maybe links to the existing HBA dtabase as meeting the spirit of this concept and other's criteria and thoughts would be the best start. over to you.
 

Hot Wings

Grumpy Cynic
HBA Supporter
Log Member
Joined
Nov 14, 2009
Messages
7,076
Location
Rocky Mountains
Revolutionary? I don't think one can develop revolutionary. It just happens. We can however be on the lookout for ideas in other areas to adapt to our aviation exploits.

If we want to reduce this to an engineering task of designing an airplane "to include those things that might RADICALLY lower the cost of flight (dollars and man hours together ) that might bring flight within reach of many many more people than now" we need to start with a list of the problems to be overcome, then move on to finding solutions.

Assume that we can build a plane that is inexpensive to build and operate. Further assume that the population wants, and will allow, general use of personal air transportation. That leaves designing a plane that can be safely flown with little or no training. FBW solves this part of the overall problem, and we are on the cusp of having everything we need to make this a reality. Once this happens we can expect our regulators will be forced to change our laws to accommodate the wishes of the masses and private industry, or the governments, will develop the infrastructure, if any, that is needed

So, we are back to trying to create this revolutionary/radical new plane. We are limited by our understanding of the laws of physics.

We have to move a mass of a specific density - people and cargo - in an on demand and sufficiently rapid manner. Using conventional methods means that we need a minimum amount of power and a minimum amount of wing area to move a minimum amount of air. Even if Synergy's goals exceed everyone's expectations by a huge margin we will still be a long way from a practical form of mass personal air transport using conventional methods.

So what variables do we have to work with?

Mass of the passengers (note: not pilots)/cargo: Unless we find a way to alter either the effective mass or density of matter we are stuck with this parameter as is.

Energy storage and conversion density: Until we develop the miracle battery, or something like Mr. Fusion, we are stuck with liquid hydrocarbons as the best available. Another option is to move the energy storage off the aircraft an locate it remotely. This can be done now, but is not efficient or up to the power levels we need. Could remote energy storage and transfer be made practical?

Drag: Humans are only getting bigger as we evolve. We have a minimum area that will produce a minimum amount of drag. Unless we find a way to selectively alter the Reynolds number of air our aircraft will still have a finite amount of drag. Can we find a practical way to alter the air?

Lift: The math for this is pretty ridged and well defined. We need X amount of wing to move Z amount of air to provide the required lift at speed Y. Without resorting to massive amounts of power, which we don't yet have in economical or practical form, to get away from having to use fixed wings to move air to provide lift any personal air transport device will most likely be larger than we would like. Finding a way to shrink the wings for ground use or storage is another option but so far no one seems to have been able to do this. Again, Altering the physical characteristics of the air is an option. Can we do this?

Propulsion. Interrelated with the drag parameter. Moving air to provide propulsive energy has the same limitations as does a wing to provide lift. We either alter the air or find a way to use some other mechanism to transfer energy to do work. Can we do this?

So it seems to me that unless we find a practical way to alter air, develop some new very high density energy storage and conversion system, or find a way to bypass air as a mechanism to transfer energy we are stuck with evolutionary, rather than revolutionary, advancements to develop general use of personal air transport. I'm not saying that saying that revolutionary is impossible, but given the limitations of my rather classical education I'm not able to think that far outside the box.

[h=1]"Scientists investigate that which already is;
Engineers create that which has never been.''
[/h]
Albert Einstein
 

henryk

Well-Known Member
Joined
Mar 8, 2010
Messages
5,282
Location
krakow,poland
It

=Russian saids="iff you have power,no need in ratio!"...

-Terrafugia TF-X=300+600 kW for 4 person\400 kg\ =circa 0,5 kG thrust from 1 kW !!!!!

-dr Sorokodums flapper=circa 100 kG thrust from 1 kW...

-hard to compare!

-Single Wire Line=circa 30 kW electric energy transmitted via 8 mikron tungstam wire...
 

PTAirco

Well-Known Member
Joined
Sep 20, 2003
Messages
3,528
Location
Corona CA
Well, I guess we need to talk about this: It

I'll talk. "Terrafugia launches the next generation of flying cars!" What happened to the first one? The Transition? Oh, yeah, it basically failed. But hey, they're already a step ahead. Based on their success of pumping millions and millions into a bad car that flies badly (or a bad airplane that drives badly) and which you cannot buy a single example of - they are now ready to go one step further and give every garage in America its own vertical take-off, anyone-can-fly-it Jetsons transporter. Well not quite yet. I quote: " ...this will need orders of magnitude more money that the Transition. More like hundreds and hundreds of millions. We'd like to keep it under one billion..." ONE BILLION! (From an Avweb podcast.)

How often do we see this nowadays? Companies that have succeeded in making a great living for their bosses by doing nothing but perpetual R&D. Never producing anything marketable or even remotely successful. I have way too much faith in humanity; I keep thinking people are smarter than to give money to these enterprises. But they do. And keep giving more!

I guess I should applaud these people for being able to make a great living at the expense of gullible investors.
 

Aircar

Banned
Joined
Feb 20, 2010
Messages
3,567
Location
Melbourne Australia
The comments about the basics of physics are all assumed to be so yet the greatest scientist of his time (Thompson -Lord Kelvin ) declared that he had 'not one molecule of faith in the attainment of manned flight by whatever combination ..etc etc' --somewhat proven in error by a couple of ill educated bicycle mechanics . WE know the ground rules and that being so claims of marvellous but mysterious physics defying 'breakthroughs' are specifically ruled out (the Synergy was mentioned and the just announced Terrafugia TFX - spoken of on the roadable thread already is rightly taken to task over their 'business model' -a la Paul Moller . It was in today's Melbourne Age newspaper (same paper that refused to even listen to an Australian design only a week ago -we call it the cultural cringe here --anything from overseas is great but something local has to be no good --the exact opposite of the American "not invented here" syndrome (or at least how it was some years ago )

The spiel on their website BOASTS " I megawatt lifts you" - 1 BLOODY MEGAWATT - ca 1200 Horsepower !! --that is progress? Was a time it took one horse to get a man around .... The pandemonium associated with absorbing one megawatt in those props would be indescribable -- they look to be hoping to control the pitch of each blade individually to get control in hover and transition with pico second response times needed (almost) and god knows how complex a flight computer . The far more sedate V22 tilt rotor (Osprey) has encountered numerous snags not least being the vortex ring state and settling under power . It makes no sense to fold back the rotors in flight and then use a second (ducted)prop and motor with higher disc loading and having to stop and fold the multi blade proprotors (this design is a pastiche of several 1960s tri service VTOL concepts --in their case folding the props in flight allowed jet speeds . As it was no stopped rotor or folding rotor design made it to flight test while much simpler designs ran into big problems .

Topspeed- I won't be censoring anything you post least of all because it offends the conventional mind - go for it (but not if you want to preserve patentability as a warning ) . It was only because people THOUGHT that flight SHOULD be possible based on intuition and watching birds etc plus a little mathematical common sense that they perservered and showed that the 'impossible' was not.

(incidentally Percy Pilcher was a laboratory technician at the same university as Kelvin and Kelvin knew about his private work on flying machines which might have given rise to the infamous quote. )
 

RonL

Well-Known Member
HBA Supporter
Joined
Jan 9, 2007
Messages
502
Location
Texas
"... The conversion of heat (or caloric) into mechanical effect is probably impossible, certainly undiscovered"

Kelvin does leave this open to a probability of being accomplished (IMHO). What has been impossible for me, is explaining how it can happen
:depressed
Perhaps one day it might happen (presenting a clear explanation of what is in my thoughts), two processes working against one generator inside a single cold reservoir, can bring in heat by two methods in exact proportion to electric energy sent out..... a lot of mechanical detail inside that cold reservoir ;).
 

Dan Thomas

Well-Known Member
Joined
Sep 17, 2008
Messages
5,345
The comments about the basics of physics are all assumed to be so yet the greatest scientist of his time (Thompson -Lord Kelvin ) declared that he had 'not one molecule of faith in the attainment of manned flight by whatever combination ..etc etc' --somewhat proven in error by a couple of ill educated bicycle mechanics .
Yup. And 110 long years later we still have exactly the same layout: wings to lift, and propellers driven by an internal-combustion engine to produce thrust to achieve forward speed to generate the lift in those wings. In fact, those bicycle mechanics were building on previous work by Langley and Lilienthal and others. Since 1903, most change has been in airframe materials and power density. We still have to run for long distances to attain speed to fly, unless we can afford helicopters, and look at the horrible power-to-weight ratios required in those things with their long, efficient rotors. I laugh when I see machines like Moller's trying to fly on tiny fans. Very good at turning gasoline into noise and not much else.

If every man had a flying machine in his driveway? Imagine the pandemonium in the air. Look at the craziness on the highways and streets now, and add a third dimension and mix in all the guys who wouldn't fly by the rules or who would disable the computerized controls so they could do whatever they want. Stop signs mean little to some folks; what good would computerized ATC do?

Dan
 

jedi

Well-Known Member
Joined
Aug 8, 2009
Messages
2,121
Location
Sahuarita Arizona, Renton Washington, USA
..... If every man had a flying machine in his driveway? Imagine the pandemonium in the air. Look at the craziness on the highways and streets now said:
I look at the gnats flying in a swarm and think this is the key to air traffic control. If only every aircraft had a flea brain there would be no mid air collisions.
 

karoliina.t.salminen

Well-Known Member
Joined
Oct 7, 2008
Messages
407
Location
Finland
What would truly revolutionize aviation:
A fixed wing plane that does not need airport to take off and land, in other words has tiltable rotors.
Airport fees are a major cost nowadays, especially in Europe. You need to pay landing fee, parking fee, car parking fee and also time to get to distant airport far away and then pay the gas for driving there as well. etc. And if you would use autogas in the plane, and you are not allowed to drive with car at the airport, you have to carry the gas for the plane by foot in canisters. Not very convenient. Using an airplane to travel short to medium distances is not at all practical because of this (eg to get to next city with the plane that is 200 km away takes more time with even a fast plane than driving there directly by car or motorcycle), and this would be the cure, personal air travel would become somewhat desirable.

Hybrid electric tiltrotor could be a thing that could disrupt the market. You park in your own garage, and you do not go to airport at all, and refuel at gas station for cars. This should be feasible at least with a computer stabilized tricopter configuration where the front rotors would be tiltable. There is a UAV with that config already. A single or two seater would not be that much further stretch from that UAV.

IAI Panther - Wikipedia, the free encyclopedia

Hybrid system is required because the stabilization in tricopter mode with piston engines might prove to be tricky due to too slow engine response time, and I suspect that is one of the problems Moller has always had. Therefore a piston engine with good power to weight ratio (ie one from motorcycle) drives generator and the tiltrotor flies with electric drive motors. To have redundancy in hover, two independent motors per one shaft could be a good idea. Battery could be usedfor emergency landing in case of generator engine out. Because the plane lands vertically, emergency battery does not need to have very long endurance, just enough to survivably land the thing if generator breaks.

If you check a video how Panther UAV does transition from hover to flight, it actually just flips the prop and does not have more special system than that. To make the same with the big props and big plane of course is more tricky and things will happen slower on them, but a single seater as I said, would not be that much bigger than Panther.
 
Last edited:

Head in the clouds

Well-Known Member
Joined
Mar 11, 2012
Messages
1,983
Location
Gold Coast, East Coast of Australia
IAI Panther - Wikipedia, the free encyclopedia

Hybrid system is required because the stabilization in tricopter mode with piston engines might prove to be tricky due to too slow engine response time.....
Much as I'm a fan of the hybrid electric concept I wouldn't disregard ICE power for this application. In fact even electric motors are rather slow to respond for the true needs of a rotored aircraft. The use of collective pitch change as part of the prop's constant speed system would allow ICE engines to be used, should they be the preferred powerplants.
 

karoliina.t.salminen

Well-Known Member
Joined
Oct 7, 2008
Messages
407
Location
Finland
Much as I'm a fan of the hybrid electric concept I wouldn't disregard ICE power for this application. In fact even electric motors are rather slow to respond for the true needs of a rotored aircraft. The use of collective pitch change as part of the prop's constant speed system would allow ICE engines to be used, should they be the preferred powerplants.
It depends on the rotating mass and power how fast it will respond. You can not generalize electric motors therefore as quite slow.

ICE engines are not good also because of reliability and redundancy needs, regardless if the stabilization is handled with prop pitch control or prop rotation speed. Any of the three props goes away and a fatal crash will result. Electric motors can be more easily doubled to same shaft without complex mechanics and also battery can be used as a backup, in event generator fails and this can result magnitudes safer system.

We were speculating this today with my partner that
- This plane could have: 2 x Kawasaki ZX6R engines, 130 hp each (turbo possibly needed though to replace the ram air of the motorcycle on takeoff/hover) turning two generators (for redundancy). Each generator can be designed quite small and lightweight due to the high rpm it is turned - the takeoff would be e.g. at 14000 rpm (redline is at 16500 rpm) and cruise around at 8000 rpm. The engine can be run at 14000 rpm everyday (last time I was making my bike scream, was today, 1st gear 120 km/h = 14000 rpm :) and 8000 is just normal highway rpm at fourth gear. Not the most reliable engine maybe and not the longest lasting maybe, but has very good power to weight ratio and is cheap as salvage from a wrecked bike and two of them mitigates the redundancy issue (1 engine + battery = safe emergency landing) also. The initial takeoff power could be doubled using battery for a very short period of time (until the transition to horizontal flight)
- Smallest possible footprint that would generate enough lift for the plane would be - what else - than a Facetmobile kind of shape - lifting body. Without facets of course. But that could enable fitting e.g. on a street. The lifting body geometry would lead to CriCri-like front prop placement (pylons). There could be little folding or manually retractable extension wings outboard the lifting body center section. Of course the plane could be also high aspect ratio like the IAI Panther, but it would be more difficult to find landing spot for that long wings and it would be less practical as go-everywhere plane.
- the three props would be as big as fits to have as low as possible disc loading

Well would be interesting to now calculate how large props would be actually needed to lift the ~1000 kg thing up with the power from the ZX6R engines without running them exactly redline on takeoff. Would be very cool sounding craft too. Not the Lycosaurus brrrrrrr but a sound of a sportbike.

And then the control system:
One very simple possibility:
Raspberry Pi commanding Arduino via mavlink protocol and the Arduino running software which is a combination of Arduplane and Arducopter. No supercomputers needed, no lasergyros, no ultra-expensive stuff, no BS, just stuff that works. Solid state mems sensors - very inexpensive stuff, that would be no problem at all to double (or quadruple) for redundancy.

So this plane could be revolutionary not only in vtol capability but also in price, bill of materials total could land to a number that is less than the price of one Lycoming IO-360.
 
Last edited:
Top