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Thread: Synergy Aircraft

  1. #121
    Site Developer Jman's Avatar
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    Re: Synergy Aircraft

    Ive just lost another detailed posting (!!) -- there is some sort of time out apparently but it is just too frustrating
    Ross, make sure you have cookies enabled. Also, anytime a lot of work is involved, it might be worth selecting and copying your work in case it flakes out on you. Then you can just paste it in again and submit it. Not a perfect solution but prudent when working with computers and the internet.

    I'd like to reiterate what Topaz said. Sarcasm doesn't have a place in good natured debate.

  2. #122
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    Re: Synergy Aircraft

    Ross,
    EAA365 is really bad about losing a post. This forum has not been a problem for me. (my posts are shorter) Just copy and paste as Jake said.
    I agree, you should end any pointless debate. I also agree with your point that the Synergy design will not save GA (even if it did work as promised). We don't need fast six place airplanes, in my opinon, we need entry level.

    Ross, please post on other threads, I like your comments.
    BB

  3. #123
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    Re: Synergy Aircraft

    Quote Originally Posted by BBerson View Post
    EAA365 is really bad about losing a post. This forum has not been a problem for me. (my posts are shorter) Just copy and paste as Jake said.
    Being one of the longer writers too, yepz CTRL+A, CTRL+C, CTRL+V
    I also agree with your point that the Synergy design will not save GA (even if it did work as promised). We don't need fast six place airplanes, in my opinon, we need entry level.
    This is where I'm totally with John.

    Entry level is there. A C152, a Sonex or the LSA's are about as "entry" as it gets, as long as we're speaking practical aircraft that can be used to travel and are affordable and reliable for an owner. If we're extending it to "fun", gyro's, ultralights and so on qualify too.

    But that fun/owner market is limited and less and less people can afford the time and money for it.

    If GA really wants to grow we should grow in the commercial market; transportation. Cirrus kicked off an "airtaxi" concept and I think it has huge potential. Then you're looking at 4-6 seat small aircraft, ranging from the faster piston singles to the cheapest minijets. If prices can be around 1 US$/mile (including everything, so fuel, finance, insurance, pilot) you're looking at a market that's a multiple of the current GA fleet.
    There a slightly bigger aircraft (3 passengers+ lots of luggage) makes a lot of sense, especially a pusher like John's design because it's quiet. Not only does that give the passenger(s) some "privacy", it's much more comfortable than the typical spam can. Also, for a reliable taxi service you're looking at IFR, de-ice (pressurization), possibly a lavatory, a very quiet cabin and half a dozen other things. A small, cheap aircraft simply doesn't have the payload to carry all that.
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  4. #124
    Registered User Tom Nalevanko's Avatar
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    Re: Synergy Aircraft

    Pushers may be quieter for the passengers but they are absolutely terrible for people on the ground. My airport is the base for a fleet of Piaggios and there is an unwritten agreement that they only land straight-in or from a pattern over the agricultural lands south of the field. Their noise is extremely irritating. They overfly an older part of the city landing straight-in only because no city councilpeople live there, so that's the way it goes. I believe that interior noise can now be mitigated equally whether a tractor or pusher design.

    I think that passengers will be very uncomfortable riding in John's design unless he provides a co-pilot seat next to the pilot. No one wants the fear of what-if the pilot collapses on the controls and no one can even come close to trying to save the situation. I guess they can pull a parachute but they may be going too fast or may pull it when not desired.

    And the old school in me believes that tractors are the way to go and that wings belong on top. LOL

  5. #125
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    Re: Synergy Aircraft

    Lunch break!

    Thank you Mr. Nolan. My words to you are sincere; my Dad and I have always had a love for amphibious aircraft and we were fans of the Opal. I regret that I was not aware of your contributions to so many other notable designs, but I tend to pay more attention to the work itself than to the people behind the designs I notice. I consider that a personal fault to some degree.

    Regarding care and refinement: it takes physical restraint to keep me from designing Synergy v.31-99 as I love the process and there is always another improvement that can be made. But at some point, my hardwired inclination to endlessly continue doing just exactly as you wisely recommend must stop until we gain another experience benchmark.

    Tom: Sorry; can't go there regarding hypothetical numbers. re: side by side; we have side by side pilots in the six place, and side by side pilot/copilot, with an optionally pilotable seat ahead, in the five place. Who, if anyone, gets the VIP chair is up to the PIC. This opens some interesting possibilities for later versions and instruction. Re: pushers; The fact that most if not perhaps all current pushers are noisy is irrelevant to whether pushers must be noisy. Wake propulsion favors small diameter multiblade impellers, which are among the quietest concepts possible when designed as such.

    Duncan: Thanks again for your encouragement.

    Bill: I think what John Paul meant in the video is that we see future 'general public-friendly' creature comforts as mandantory, not optional, and regardless of our design these topics touch a nerve that will trigger a resurgent industry-wide motivation to listen to the future aviation customer, who quite frankly will greatly outnumber 'us old guys' when they emerge. I don't see how Synergy can 'save GA' as it is still a science project at this point, and the key to getting it done by whomever using whatever is about value and volume. I do believe that the principles it explores (which include the idea that fast airplanes still ought to be able to land very slowly on short unpaved runways with less complexity) can't really be ignored if we are to change the paradigm successfully. As to seat count, I think NASA has it right this time and their conclusion mirrors a lot of discussion about the reason cars won the first war over cheap transportation. Good points made in SAE paper 2006-01-2429 and in Mark Moore's latest summary of the work done under their last aeronautics initiative.

    I'm excited to fly her solo, as well. I don't think I'll mind the seats and space behind me if the economy beats the norm. The image below is out of date re: aerodynamics (v.21!) but the footprint is still about the same.
    Synergy Aircraft-synergy-vs.-c172-size.jpgClick image for larger version

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    Viscosity is a bullwhip.

  6. #126
    Registered User Tom Nalevanko's Avatar
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    Re: Synergy Aircraft

    "which include the idea that fast airplanes still ought to be able to land very slowly on short unpaved runways with less complexity"

    John; thanks for your reply. With regard to your very important statement just above.... What ratio of cruise to landing speed do you think that you will be able to maintain? This ratio is very telling. Hoping that it is a big number for Synergy.

  7. #127
    Registered User Tom Nalevanko's Avatar
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    Re: Synergy Aircraft

    John,
    Thanks for the Synergy vs C172 diagram. Your side view reminds me of the Questair Venture, a good performer.
    Blue skies,
    Tom

  8. #128
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    Re: Synergy Aircraft

    Maybe I should clarify my position vis a vis this thread -- I don't have any ill feelings towward John Mc Ginnis as a person and I hope I have expressed my genuine delight in seeing something being created that is not a relic from off the ark or the umpteenth scaled down re incarnation of the P51 Mustang for example ( let's see they've done 9/10ths,7/8ths.3/4,1/2 ,2/3. 60% ....... what's left ? Not a joke actually the firm that I did some redesign and tooling on their Alvarez Poliwagen 'derivative' ['Cobra'] is now in the process of building yet another scaled P51 . With all the opportunity that the experimental category provides why go back to the distant past and build someone else's design made for a totally different reason ? (Kindelberger would be appalled I'm sure )

    The Synergy was, until very recently, a series of pretty undefined but extraordinary claims that revolved around not a particular design (we had no idea of specifics) but a fundamental 're understanding' can I put it -- of the very foundations of aerodynamics and even physics . Goldschmied had indeed published papers with titles like "the self propelling body" and without wading through them to filter the research findings seemed to contradict conservation of energy even -- his work has been sporadicly noted over the last thirty years or so even in mainstream journals like Kitplanes (1985 ) --I had access to the biggest aerospace technical library probably in the southern hemisphere at the defence science and technology organization (DSTO) for a couple of years while working there on contract and had earlier filtered right through the technical libraries of three major universities looking for anything that might apply to improving small aircraft and ultimately roadable aircraft -- thousands of papers in total but most of them are now available at the click of a mouse and powerful computer programs now take out the sheer drudgery that used to be needed even to lay out airfoils let alone three dimensional bodies (and do analysis of flow fields and forces etc etc ) As an engineering patternmaker (amongst others) I have seen the total elimination by CAD CAM of this traditional field , still the old adage "data is not information, information is not knowledge and knowledge is not wisdom" -- I have seen examples of this with recent graduates who often fail to check whether they are in the ballpark but have figures 'accurate' to ten decimal places . This has led to cases of egg on face syndrome and a bit of caution thereafter .

    The explanation for unprecedented levels of performance and revolutionary revelations to be due to 'open thermodynamic systems' as opposed to the standard adiabatic,closed control volume basis for 'classical' aerodynamics has not been elaborated on or given any theoretical underpinning --as least to my mind. It COULD just be possible to extract heat energy from the surrounding air by some means using the well known temperature drop with pressure in a vortex ( aerocyclone cooling systems are known ) and some sort of non conservative phase change heat extraction or something hypothetical along these lines -- an "open" thermodynamic system requires the import of heat energy or it's equivalent --as would apparent negative drag --or the 'gain' of energy from your own tip vortex rather than just reduce net losses by well known means ( Whitcomb winglets, Spillman tip sails, Tip tail, windturbine etc ) Something overturning the aerodynamics of closed or non planar, multiplane or tandem wings --such that carrying opposite loads is seen as beneficial -- has yet to be proved and seems non credible.


    Break


    I don't think John is trying to run a scam with his design (one of the rules for the forum is not to solicit money or use it to push something commercially ) which is not something I can say for the likes of Paul Moller and his ostensible 'flying car' "Skycar Volantor" -- he never attends or displays his wares at Oshkosh or other Aviation conventions despite decades of making astonishing claims but never demonstrating a working man carrying gadget --not ever flying it in non VTOL mode off a runway for example but also having raised ,up to, $250 Million and spent it all without much to show for it and even then his vehicle is simply not capable of road operation (or amphibious as he also claims ) He has shown 'new designs' consisting of a cast off BD5 fuselage with tow of his ducts stuck on --and raised more cash-- his latest is a cheap die cast model Ferrari with holes bored through it ("lift ducts") and a crude folding wing that would need to do 150MPH to lift it .

    I met him at the SAE 'future transport' conference at Costa Mesa in 1998 and his reaction to unwelcome ,but invited, questions after his - non technical but slick,- presentation was to fold his papers and walk off stage .
    There is another 'start up' aerospace company making vast volumes of 'corporate speak' about apparently non existent aircraft with an all singing all dancing website -- their design of closed wing system, rear wing joined via both tip fins and inboard etc is almost a mirror image of the Synergy in fact but at higher aspect ratio. Check out STAVATTI aerospace -- I'll check the spelling but it is at least close and should Google ) -- when outlandish claims are made for aircraft that the public will associate with "joined wing' or 'roadable aircraft' and are not legitimate the fallout damages the whole movement so the ethics of every player in the game are of concern to all.

    when I visted Julian Wolkovitch in 1990 and showed him photos of my aircraft and various other previously built things (local aircraft design was illegal unless fully FAR 23 compliant --which is why I again headed to the US to have some chance of doing anything in aviation design -- he particularly liked my joined wing free flight models and sailplane then under construction and offered me a job building prototypes for him (ACA industries) --he died later that year and thev firm was wound up when I returned en route to Oshkosh in 1991 (Barnaby wainfan from Kitplanes wind tunnel fame was brought into our meeting --showed then both my copy of "An airplane in every garage" by Dan Zuck who live only a few miles from them but had been 'forgotten' and "the book' was treated like I had a Gutenberg bible by both of them (!) --I met Dan the next year and he showed me his "Planemobile" flying car from the fifties -- extraordinary that such ground breaking and pioneering work was just 'overlooked' in his own country ( A prophet is not without honour save in his own land, his own time and among his own people)

    At Oshkosh in 1998 Bruce Holmes from NASA Langley held up a book in front of a crowded tent of hundreds of aviation enthusiasts and on the same stage as Burt Rutan and John Roncz -- he creditted this book with inspiring the NASA "AGATE" and Small Aircraft Transportation System (SATS) programs --intended to really revolutionize aviation and the whole personal transport picture for society at large.

    The book was "An airplane in every garage " -- I had a tear in my eye and just wished that Dan could have been there and seen his lifelong dream apparently about to bear fruit . The CAFE competition is the outgrowth of that inspiration but has diverted away from the original intention and aim --back to runway to runway standard aircraft with all their shortcomings no matter how fast in theory. Dan would roll in his grave if he could see where it has gone since. --although I think he too would be intrigued by the Synergy as an example of unorthodox aeronautics and something of this century to quote John himself
    (I was put up overnight in Dan's study surrounded by pictures of the Lockheed S3 Viking,SR 71,F 104 and others all signed by Kelly Johnson and thanking him for his fine work in the Skunk works --it was because of Dan's 'top secret' status that he was prevented from selling his books which had his home address in them --he had boxes of unopened copies and gave me a "new" one to accompany my beat up old one and signed by him with the words "Utility will be aviation's salvation" --meaning that we don't need more speed in the air or any other thing beyond real everyday useability and usefullness.

    When I see or get wind of anything promising any real revolution in aviation or roadables etc I track it down regardless of the cost if there is a chance of furthering the same dream of a real impact of flight on the lives of millions of people to their betterment in everyday affairs and at the sort of cost that can be affordable to even the young (who could afford to fly when I was young but not now --they are the future rather than trying to create a flying "Cadillac"(as per the Synergy video) I think that we need to start with a flying "model T" or even better a flying bicycle.
    Revolutions seldom start from the overindulged rich who want still more but mostly from the downtrodden and underprivileged who just want SOME and will be happy with it (be "IT" democracy,freedom,food shelter or mobility -- giving a man in a wheelchair or on a bicycle "just" 200 MPH will do a great deal more good than disparaging a "200MPH homebuilt" that no longer satisfies the owner --we live in a world where the vast bulk of humanity have never left the ground in any fashion --or even made a phone call so 'revolutionary' can mean a lot of things rather than just breakneck speed.

    Break 2

    I had another drop out and can't trust even 'refreshing' periodically so this will be quick and to the point.

    As to patenting and claims associated.

    1. I do not believe there is anything transcendental about the aerodynamics or physics involved ( ie not an "open thermodynamic system" -- no exploiting exhaust heat or any new art involved --neither does this design rely on anything new on the other hand it is all well known art )

    2. I am philosophically opposed to 'blanket' patenting in ORDER to exclude others from experimentation --if a truly novel idea is found and wanted to be patented that is OK but a 'dog in the manger' attitude to 'protecting' all possible combinations or variations that could be devised on a particular theme is oppressive --the little 'thumbnails' revealed on this thread indicate such a course is likely (the blended wing body with tip joined elevator and jet engines is clearly something at an entirely different scale --in any event the recently published Luigi Colani blended wing body biplane is in essence equivalent and not patented but in public domain so precluding a valid patent.)
    ( I visited SCALED in 1990 and showed Burt rutan the exact Pond Racer configurastion published in English Aeromodeller from the 1950s to his amusement (twin rubber band )
    also the Voyager in a Mc Donnel advert . To top it off his patent on the 'cantilevered flap' -as on Grizzly and ATTT was anticipated in a second world war German patent by Kurt Tank (which he thought was OK since he respected him !!)

    3. I state here, for the record, that I believe that I have anticipated (in both theory and practice) the aerodynamic 'principle' relied upon in the Synergy aircraft as disclosed by drawings and computer rendering -- discounting the designer's claims to some not understood 'open thermodynamic system' or supersonic flow effects .
    I also believe that the prior art in couple wing systems also 'teaches' an identical aerodynamic design .

    Specifically, - in relation to a wing or airfoil system consisting of a main fore wing connected to a rear down lifting wing by a pair of inwardly cambered and appropriately toed vertical or substantially vertical rear swept surfaces that may or may not function also as directional fins . Any of the surfaces may additionally be twisted or vary in camber,airfoil or to an extent sweep or vertical location (ie not straight or parallel for example) without affecting the operating means or principle.

    Although I conceived such an arrangement for a flying vehicle ( ram wing surface effect aircraft and applicable to full free flight ) I first embodied this in a race car called the "Bob Jane Monza GT" and well known from published sources,-- to be quoted - they date the public domain disclosure to April 23 1982 as the latest possible date -- from publication in "Australian auto action " front cover and thence Pg 10 -- this was the first public release of any pictures or description of the vehicle embodying the closed airfoil system.

    This car was subsequently photographed and had considerable exposure in journals that received wide exposure both within and outside Australia --in the hands of Allan Grice it won the GT class Australian championship in 1983 (published evidence again with clear colour pictures ) --much of the,then,innovative aerodynamic design was internal in the cooling system but the external aerodynamics of interest in this case is easily seen --the novel "slotted' A pillar design was complimentary to the flow into the rear airfoil system but not strictly relevant to the functioning of the rear aerodynamics but together with the internal flows and the mixing of those flows in the front of the vehicle crucial to the stability and handling of the vehicle.

    In this context the rear airfoil, main cambered vehicle body and the supporting side airfoils are relevant to disputing a subsequent patent claim . No attempt was made to patent the aerodynamic design at the time of incorporation into a car (1982) and the drawings and models of aircraft using it are unpublished but have been disclosed .

    A brief description of the operating principle follows.

    (shutting this window and then sending )
    Last edited by autoreply; May 20th, 2011 at 07:48 AM. Reason: Merged several posts in one topic

  9. #129
    Registered User rtfm's Avatar
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    Smile Re: Synergy Aircraft

    their design of closed wing system, rear wing joined via both tip fins and inboard etc is almost a mirror image of the Synergy in fact but at higher aspect ratio. Check out STAVATTI aerospace
    Come on Aircar - this is hardly a fair comparison. Inasmuch as all aircraft have wings, I guess you could say they are all "almost a mirror image". If you honestly think the STAVATTI SM45 Aviara shares a similar wing to the Synergy (beyond the obvious visible fact that it is joined) then you seem to have missed the basic design principles behind the Synergy completely. And because I have no doubt at all that you have a pretty savvy understanding of how the Synergy is purported to work, I can only ascribe your comparison to a moment of meanness.

    Play nice.

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  10. #130
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    Re: Synergy Aircraft

    Hold your horses just yet Duncan --I have some 'homework' for you -- if you are willing to indulge a little effort and I am taking you as a trustworthy supporter of John's so could be taken as an 'honest broker', but certainly not biased towards me in determining this matter .

    It is :--
    If you, or someone you know in Melbourne that can come to me, or I go to them, with the documentary and photographic (or if here, solid ) evidence to back up ALL the claims and facts I have made here and then report back to this website if it is as I say .

    Simple and open offer to test my veracity and the substance to this claim of patentability .-- or the existence or not of some hitherto unknown physical effect .
    No secrecy, no non disclosure agreements or mystery. So how about it ?

    The significance of the STAVATTI configuration is merely that it is a variation on the same structural and aerodynamic layout -- adding a canard to John's design and then stretching a little here and there will transform their embodiment into John's basic layout --you cannot just do some 'topological' alterations and either evade a valid patent or likewise merely change relatively arbitrary proportions to create a 'new' patent . (extending John's wing or tail outboard would create more span and operate in the upwash field to get some 'free thrust' like Spillman tip sails (google) --the STAVATTI wing does that as do non tip joined joined wings in general --if you want low induced drag you cannot beat span )

    A patent covers a basically non dimensional idea and the embodiment is very secondary (the Lippisch delta wing is not invalidated if the sweep angle is changed for example --many invalid patents are issued though and just never used or need to be challenged . a recent example of a falsely claimed patent was for the much touted and awarded "Freewing" --identical to Dan Zuck's design from 1938 disclosed in his book but also being fundamentally flawed (no roll damping in essence ) as he found out by full scale test . Paul Moler copies the Lippisch Aerodyne lifting duct without acknowledgement --but this is drifting off the specific case involved here.

    My point about the STAVATTI website thing is that there are reams and reams of verbiage about their corporate plans for world domination almost with more buzzwords per square foot than most self help tomes but very little if anything that is remotely concrete --John has produced at least a flying model and looks to be actually in the throes of attempting to put something into the air .

    Without exception designers will say that they are 'aiming to make it light,strong,fast' etc etc as though every previous designer had wished to make things heavy, weak or slow by inference -- either they were stupid or ignorant or lax in this scenario unlike the proponent telling the story . (in this case John is claiming prior ignorance by others and that he has discovered a wholly new phenomenon unknown to others 'familiar with the art' to quote patentspeak. His embodiment may or may not in fact incorporate some marvellous new concept --either way it could still fly, or not, well or badly or work for other reasons than his claims ( for example Withold Kasper made incredible claims for his flying wing glider, and subsequent testbed powered tailess aircraft ,to have discovered an entirely new lifting phenomenon and there were anomolous results and flight behaviour --it was extensively wind tunnel and free flight tested by SAAB (who pioneered vortex lift aerodynamics) and found that his patent flow structure simply did not happen --any unusual behaviour (which there was) was inadvertent and due to almost the opposite flow field to that he conceived --like much of science this led on to discovering some usefull new 'art' (spanwise blowing, enhanced vortex lift etc )

    Every claim to have discovered "cold fusion' has to be taken with a grain of salt and the saying "extraordinary claims require extraordinary proof" is true -- I have not seen the model even in slow flight or at the limits of control -- it had 3 HP according to the website --you can fly a full size sailplane on that much power . You would want fast at least (give me half a day and I will fly a standard toilet seat by radio control --an annular wing actually and quite efficient but proving next to nothing about the flight envelope and nil quantitative --you may have known of Ben Buckley flying the annular wing glider at Benambra of this exact shape .(?)

    Break

    A bit distracted in responding to Duncan but the offer to verify the facts is itself germain to this issue about 'corralling' whole fields of aircraft design with blanket patents --leaving aside the Synergy as an aircraft there are the( now we find patented) claims that have preceded it for eighteen months on this and the EAA 365 forum that have amounted to a build up to a great revelation only just made 'flesh' (a few days past to most of us )

    Whether John and Stavatti choose to cross defend patents or fight it out in a court over who is the most 'original' I will just do a pre patent disclosure disclosure here so that others who might be disadvantaged in future can make up their own minds if their hands are tied .

    Even if the outlines of the Synergy were still secret the principle of demanding truth in description of a product is unaffected and knowing that the assumed principle was not in fact new could save them a lot of lawyers fees both upfront or later on.

    When windsurfers appeared there was a rash of legal action to prevent other companies from entering the market and public advertisements appeared asking if anyone knew of the principle of a stand up type 'sailboat' using manual fore and aft movement of the sail to steer and balance -- many came forward with the earliest being in the 1800s (earliest photographic possibility in fact )and one from a bloke who sailed ammunition cases across a river using a hand held sail during WW2 in New Guinea --in the end the high priced monopoly brand was held to be open domain .

    Returning to the BobJane Monza and the rear end aerodynamics -- I had built my Stiletto canard "mini eze" at that time and needed to get the actual NASA wind tunnel data in order to load the winglets and to also allow for the upwash effect of the canard --beyond it's tips - on the main wing in oder to satrify the chief technical officer i who was to witness the proof loading --a Whiffle tree had to be applied to the winglets and I was surprised by the amount of load involved and rechecked some of the figures and looked into the other data I had on closed wing systems and things like Nenadovich which a friend who was a technical librarian could get for me .

    The flow mechanism that applies to winglets includes the 'induced' inwards spanwise flow that tends to add to the mass flow dealt with by the wing system --it is both 'sucked into' the influence of the wing and then expelled outwards to increase the effective span in the same general way that a ducted fan induces flow into the prop disc and generates forward thrust on the ring airfoil (like a townsend ring or NACA cowling --if not screwed down these will go forward into the propeller from the thrust vector although the flow redirection by the engine inside has already cost energy so it is NOT 'negative drag' or 'self propulsion' --likewise after the actual nose cone an annulus on the forward fuselage would also 'suck' forward implying negative drag but it only happens because of the redirection of the flow ahead of it so there is no defying Newton involved .

    At about this time the America's cup challenge had been won by Australia 2 using the 'revolutionary ' "winged keel" which was simply a type of 'fanned' wing tip using some of the camber principles of the Whitcomb winglet but limited by the need to work on opposite tacks in a boat .

    I was approached by a friend of Bob Jane's and introduced to him to see if I could help him with overheating of the original Monza bodied racecar and then became aware of the shortcomings of the body aerodynamics and was asked to submit a proposal of how to improve it WITHIN the class race rules -- one feature of these was a prohibition on going outside the existing production vehicle's side profile above the wheel acle height nor could the rear airfoil be visible from head on --ie within the top passenger 'turret' --this very much limited the span and height possible and led to examining the options to get more downforce (with up to 800 HP to be cooled and held on to the race track )

    The aerodynamics of closed wing systems giving a greater effective span --and free directional stability from the side fins which had just been flat plates at the then state of the art and without any airfoil section,camber or twist and no angle of attack .

    The previous investigation of a very narrow (boat 'hangar' width) water skimmer had also led to looking at 'active' vertical surfaces and the pitch up or down tendency in ground effect between waves that resulted in wallowing like a hovercraft -- and coupled wing systems (that did not look like Lippsch's either for patent reasons...... )

    Break 2

    So in the wash up, a pair of airfoils, lifting in opposite directions -- as on the rear of a race car and the upstream cambered body -- (arranged in a box shape regardless of the aspect ratio of the whole show) can benefit from the favourable influence of induced flow if the connecting surfaces are cambered and designed to actively lift inwards rather than being symmetrical airfoils or just flat plates --the static stability of such an arrangement in free flight is higher than with two tandem lifting surfaces but the lift itself in less and the induced drag higher as a result of trim forces .

    Peter Brock (nine times Australian touring car champion I think ) raced the car in it's first season and told me it was the most stable car he had driven and only got better at speed --Allan Grice (who won the championship against all comers( Porsche 935 etc )in 1984 said on receiving the trophy and sash "Gee, I feel bad about taking this --even my grandmother could have won in this car " -- published in Australian Motoring Year Book 1984 P218 -231 with lots of pictures . And I am creditted with the design ,by name, in the Auto action article although I hasten to add I did not seek publicity and the guy who did the story and took photos breached the security to get his 'scoop'.

    Something about the proof in the pudding was mentioned -- I do not dispute that an enclosed wing system using matched interconnecting verticals can increase the apparent span and that this is a good thing IF there is a physical constraint on pure span --as there was in this case -- but the 'span squared' term in induced power is so powerful that any any factor is dwarfed by it . Even though sailplanes have made huge strides in absolute (non dimensional )terms like L/D and achieved speeds and distances the actual decrease in raw power to fly one man has only been in the fraction of one horsepower range over the last sixty years -- a 1964 Libelle takes less power to fly at 60 MPH than some of the more modern designs simply because they are considerably heavier (150 lbs or more ) and even carry another half their empty weight, or more, in water ballast . the factors applying to a powered aircraft are considerably different and weight is a first order term and the stubby wings of things like the RVs reflect the structural cost of long span --extending the span 'grabs' a progressively bigger extra annulus of air but exacts a disproportional cost in weight of spar (and gliders have minimal payloads hence shear loads ) --the secondary benefit of most joined wings is to relieve the wing bending loads and to save weight --even to the extent of having ZERO wing root bending moments in some designs --and to stiffen and stabilize the structure against flutter or just excessive deflections (check the ETA sailplane website to see what the present structural limit with cantilever wings is --in the best carbon fibre available and exorbitant cost ) "Synergy" means getting an output or result increased by the interactions of separate parts in combination in a positive manner but with the Synergy aircraft there is no structural enhancement rather the reverse -- other aircraft that have split the tail into two pieces leaving a big gap in the middle include the Transavia Airtruck and the recent Rutan/Scaled white knights and global flyer -- the Airtruck stiffens the attachment by a separate sesquiplane and struts while the other two are very much single point low manouverability designs with very unique tasks that drove the choice .

    It is so far very hard to see any configurational advantage from not just extending the booms and adding a tail as per most twin boom pushers --that would allow the wing span to increase and be much simplified while reducing the induced drag and interferences --all in all a "synergistic' combination of features with out losing anything for the passengers . Any claim to novelty in regard to the geometry is I think dubious at best with no indication of how energy is brought into the system to be thermodynamically unique.
    Last edited by autoreply; May 20th, 2011 at 07:47 AM. Reason: Merged several posts in one topic

  11. #131
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    Re: Synergy Aircraft

    Aircar, for heavens sake! Write your text in Notepad or Word. Then, when it looks beautiful, cut and paste it into here. No more timeout issues.

    Grelly

  12. #132
    Moderator autoreply's Avatar
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    Re: Synergy Aircraft

    @ Aircar

    Grelly's sugestion is a good one. Makes it a lot easier to read your posts too. Alternatively, you can "edit" a message and add there the later parts of your posts.

    I've done that for your last 6 posts (now merged into 2), to keep this popular topic a bit easier to read.
    Quote Originally Posted by Aircar View Post
    2. I am philosophically opposed to 'blanket' patenting in ORDER to exclude others from experimentation
    I don't like it either. But if given the choice between John finding investors, because of the above, vs "open knowledge" and nothing happening, then the options really aren't that hard to choose between. Homebuilding has pretty much come to a standstill and we should applaud and support anybody trying something new.
    John has to eat too and working on a new design ain't exactly cheap and neither is building.
    Quote Originally Posted by Aircar View Post
    Even though sailplanes have made huge strides in absolute (non dimensional )terms like L/D and achieved speeds and distances the actual decrease in raw power to fly one man has only been in the fraction of one horsepower range over the last sixty years -- a 1964 Libelle takes less power to fly at 60 MPH than some of the more modern designs simply because they are considerably heavier (150 lbs or more )
    This is not completely true. If we compare apples to apples (and not a light 50 ft glider vs a 100 ft, twinseater with a heavy engine), we see that performance has improved by about 50% and thus power is cut down by a third in the Diana II for example, which has the exact same empty weight. Not a really fair comparison, because the Libelle takes no ballast with a heavy pilot, while the DII can take more ballast than the weight of Libelle and pilot together. If we do a fair comparison with the Sparrowhawk; weight has been cut in half, for Libelle-like performance, so half the required power.
    Doubling efficiency (no matter how you look at it) is pretty impressive and GA still has a long way to go before we've achieved anything similar to that leap forward, compared to 50 years ago...
    The factors applying to a powered aircraft are considerably different and weight is a first order term and the stubby wings of things like the RVs reflect the structural cost of long span --extending the span 'grabs' a progressively bigger extra annulus of air but exacts a disproportional cost in weight of spar (and gliders have minimal payloads hence shear loads)
    Most gliders have about 300 kg (650 lbs) of "non-lifting" mass. The twins are looking at typically 450 kg (1000 lbs) of fuselage, engine and payload. That's not so much less than the typical RV is it? The shear stress of a big open class ship is roughly the same as a King-Air at MTOW...

    My point being, I don't think most current aircraft with a low aspect ratio have spar weight high on the agenda. Practical issues like fitting in a hangar, fitting in a garage (for building), a limited number of ribs and so on are what drives them to stubby wings, much more than the small penalty for long, slender wings. This can be seen too in the new generation of aircraft, you won't spot many who're much below 8 and many are higher.
    Next to that, the typical homebuilt is very fast compared to it's stall and thus only really suffers at climb, not at cruise.

    For a higher span efficiency, with a soft constraint as now existing, a folding/removable wing tip (as several motorgliders already have) is a great option.
    "Synergy" means getting an output or result increased by the interactions of separate parts in combination in a positive manner but with the Synergy aircraft there is no structural enhancement rather the reverse
    I was actually most surprised by it when thinking of flutter, since so many mass of the "flying" parts are behind the attachment to the fuselage. John, any particular tactics there, or just massive analysis?
    Kennis vermenigvuldig je door het te delen.
    (You multiply knowledge by dividing it)

  13. #133
    Registered User billyvray's Avatar
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    Re: Synergy Aircraft

    So I'm getting the feeling that Aircar doesn't believe what John thinks.....

    It's getting nauseating looking at ridiculously long posts about how you don't believe his claims and then spouting your resume back as some type of proof of why you’re right and he’s wrong.

    It doesn’t matter. His plane will do the talking when/if it flies, whether it all works or not.

    If you would like to submit your own threads about your own accomplishments, please do so. I would honestly love to see some of the vehicles you have apparently worked on. Explain their benefits, what you thought, why you were right, why you were wrong. You would receive the same level of support as John has for his design.



    Bilyvray

  14. #134
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    Re: Synergy Aircraft

    Moderator remarks

    *I've deleted two off-topic posts. Normally, a bit of unrelated chat isn't a problem (I'm a frequent offender myself), but this thread is both popular and significant to several people, so let's keep this a bit more focussed.
    *Let's also keep the discussion focussed on the main issue; Synergy and the related topics, like Ga in the future and the Green comp.
    *Let's not talk people, but arguments and thoughts. Like we say here: "good wine doesn't need a crown". If your arguments, designs, opinions or thoughts are good, then arguments and/or proof alone will be sufficient.
    *Agree to disagree. Opinions vary and an internet forum is a natural place for all opinions, if reasonable.
    Kennis vermenigvuldig je door het te delen.
    (You multiply knowledge by dividing it)

  15. #135
    Moderator Topaz's Avatar
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    Re: Synergy Aircraft

    Quote Originally Posted by billyvray View Post
    ...If you would like to submit your own threads about your own accomplishments, please do so. I would honestly love to see some of the vehicles you have apparently worked on. Explain their benefits, what you thought, why you were right, why you were wrong. You would receive the same level of support as John has for his design.
    I second this notion (motion?). We can use more high-end discussion here, and without resort to sniping at someone else's work. I, for one, would very much like to see complete and separate thread streams for both John and Ross's work and ideas.
    "If you have built castles in the air, your work need not be lost; that is where they should be. Now put the foundations under them." - Henry James Thoreau

    Design Project: Conceptual Design of an "Inexpensive" Single-Seat Motorglider
    Discussion Thread for the Project: Discussion: Conceptual Design of an "Inexpensive" Single-Seat Motorglider

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