# Synergy Aircraft

### Help Support HomeBuiltAirplanes.com:

Status
Not open for further replies.

#### Jan Carlsson

##### Well-Known Member
Re: Synergy Aircraft - was it a "rope-a-dope" after all?

Using traditional tools we can plot a curve given just a few pieces of information about a spot on that curve. When we gather detailed in-flight data, there isn't a curve driving it, there are just all the data points, that usually tend to conflict to a small degree with a purely ideal mathematical curve, but not by much. If Synergy fits the usual curves given a few starting points, then the result will be that we haven't successfully used power to reduce drag, only to overcome it by traditional means. Since that completely normal process is what my design targets were based on (just relentlessly adjusted in response to new potential), I will still be happy. As the curves show, an airplane with abundant NLF potential, and its max L/D at a higher speed, scores well against other aircraft designs.

If we find that fitting the curve at the low end makes the high end data points non-conforming, or vice-versa, or if we see curve flattening or other anomalies in the data, we won't jump to the easy conclusion, that it's just test error. We'll investigate it, and such deviation from the standard predictions will tell us where and how we see synergistic benefits. From there, specific sources can be proposed and checked. It's not time to worry about 'wake prop efficiencies' vs 'cowling suction credits' just yet, but I'm sure a lot of researchers will help figure it all out.
We see this fenomen on modern gliders sink rate/speed polars, some where at medium high speeds the curve bend sharply down even more, (sink rate increase more with speed) due to that the laminar flow length is changed (wing bottom) when nose is pointed down, less AoA, the curve can not be described with a simple equation. The Synergy with help of suction will hopefully bend the other way.

Some members here say we can not fool the rule saying speed increase with the cube of power increase, but that is not correct on any aircraft, it is just a lasy dog for quick estimates, it depends on where on the drag polar curve we are, so it changes with altitude due to the changes in IAS/TAS (we come to a different place on the curve)

that rule of thumb is a combination of the power/thrust change with speed and the airplane polar curve.
the thrust= power * efficiency * (550) / V = equation is fixed, (but the efficiency change with speed) sometimes the power change with speed too, just to make things more interesting, so we (me) can make calulations till I dye (I don't want to die) it will not be 100 % correct anyway.

Last edited:

#### Aircar

##### Banned
I just lost a long response to Jan and much more -it might have saved abd be retrievable but I cannot do so right now. So a quick update of my last few hours of searching under Synergy --I have paid little attention to the PR other than anything directly linked on this site and nothing ton the rules for kickstrater until just now . I am gobsmacked at the way the checks and balances and protections have been bypassed to say the least.

One site with some straight talking I just chanced across -www.rcadviser.com/synergy-airplane-model-this or google "model this synergy airplane" gives a detached assessment worth reading. and Synergy Aircraft is Better than Cars for it Saves Fuel is another with disquieting misrepresentations that I had not been aware of till now . Neither had I checked the Synergy website to find that THIS thread is being redirected to for "technical information" and "acclaim has been universal" --doesn't sound like 'INFORMED (their captitals ) donating' as per the kickstarter rules .

#### gordonaut

##### Well-Known Member
Ross, give it a rest for goodness sake...

The man has been VERY gracious in dealing with a lot of sniping here...not from you so much and I think your critiques have been based on solid technical ground...unlike most of the vinegar pissed John's way...

But now you are starting to squawk about this kickstarter nonsense...so what...I'm glad John was able to raise a few lousy bucks...it pales in comparison to the personal sacrifices I'm sure he has had to make...have you seen some of the other crap on that website, some of which is collecting huge amounts of money...?...none of that garbage is near as worthy of any financial support as I can see...and I think all of folks who kicked in will be thrilled when the airplane flies...

You've made your points about the technical issues and leave it at that...I too am curious about this open thermo thing as my background is in thermo and I would have looked it at becoming applicable only in the region of compressible flow which this airplane does not really operate in...but whatever...it is not appropriate for the man to reveal everything at this time...it will all come out when the flight test data is complete...

Until then let's let it rest...

Regards,

Gordon....

Last edited:

#### davidb

##### Well-Known Member
I just lost a long response to Jan and much more ....
That's not a bad thing. Seriously, if you pm your proposed posts to me before posting them in this thread, I will edit them and pm them back to you to post here. They will be 1/3rd in length, weight, and drag. The message will be clear whether or not it is pertinant or just obstructive.

In the mean time, don't bother to explain why the rantings of an R/C modeler/blogger is relevant here. John addressed the blogger and has offered to answer meaningful questions. The blogger doesn't know what to ask and calls on his followers to provide questions. Granted, some of the people on HBA are also modelers, but should we be reading a modeler's blog for the answers we seek?

Sorry, Jake, feel free to delete this post and get us back on track.

#### Jan Carlsson

##### Well-Known Member
Aircar. Most time I post i use MS Word, not just for spell check ( I need that) but also to have a back up if the post is lost, I think that happend if writing a long post and some one els post in the mean time ? bean der donn datt

#### Aircar

##### Banned
As to the post it is a time out thing again --unpredictable but seems to be about twenty minutes or so at a guess .

Gordonaut -- I feel bad about your recuperative turbine stuff - I cannot afford the postage and that is a FACT -same with the other guy who requested the Lysander tandem info it too is sitting there looking at me -- $165,000 obtained from the public without any effort of technical support might be chickenfeed to you but I can assure you that I don't see it that way . I have exactly$5.02 left of my miserable working overdraft (and no idea where to even get the next feed...) just paid the rent and what bills I could sufficiently to keep the power on --and no chance of recovering $10s of thousands of dollars owed for redesigning, retooling and 'saving' one local shonk's copied design (he declared bankruptcy then advised that this wife (then girlfriend) owned the company and repudiated all the debts he had run up ) -if that isn't enough I took on a contract and built six hearses (that sell for$100,000 each) but after delivering three and building the glass bodies for three more only to be raided by a pack of heavies including hell's angels who worked for the part owner of the hearse builder who also happens to be Australia's most notorious criminal and murderer . I could go on but I thought that John's crying poor and going on about his single handed struggle (and the obvious effect it has had ) should at least be put in context --when I see the equipment and number of workers "on the payroll' that John has and the unlimited freedom that the US regulations allow it does rather gall .

But I only mention this after getting the tone here --the bankrupt 'non designer' has been flogging the whole cobra project including the tooling In built on ebay claiming to have spent "$1 million on the new development " --and seems he got a free$460 000 from our state government to boot --thanks to Bob Kuykendall of HP LLC sailplane (THE HP 24 project) for telling me this too.
Bob has done a magnificent job of building a composite sailplane --for kit building- without making outrageous claims for it or himself and funding it himself as well --I paid for all my work out of what I earned from repairing broken gliders and gen av work and anything else that I could survive on --and saved money by living in my workshop or hangar (incidentally John works in his father's workshop -- I designed my father's workshop, built a fair bit of it and then got kicked out so he could play around with an old glider and other junk .

Denigrating the support and backing of a whole family is not exactly endearing either in this context and failing to raise venture capital after trips to New Zealand and other high profile efforts might say something about the actual technical validity and prospects for a design --even Kickstarter baulked at the idea and seem to have been almost shamed into 'relaxing' their rules and there is NO 'informed' content as is demanded by their rules (they do not want to lose their reputation presumably and there is a definite matter of trust and public perception involved.)

If John can make a business case based on facts then he should have no trouble in raising capital from the many US venture capital sources -- or, as previously suggested getting unequivocal letters of support from the recognized aeronautical experts he named (and David Birkenstock is himself an 'outfielder' trying to get his -- unproven-- theory of fuselage thrust from boundary layer control funded or accepted but being told that it is wrong from the universities and others who have looked at it.

I myself gave a lecture in 1976 to the Sports aircraft association detailing the design of the Opal amphibian --took the fuselage along as well --and, apart from asking for their help in overturning the prohibition on design of Australian homebuiolt DESIGN (the full FAR 23 plus fatigue etc demand) I put myself up for scrutiny with NO limitations before a committee of their most qualified members and on the basis thatr that committee report back to the ,embership if I was spouting bull**** -OR NOT . Either way I put myself up for peer review in public and without restriction. They formed the group consisting of the top engineers in australia's aircraft industry and produced a report that confirmed my design .

I will send you that report Gordon that I would like you to post here and as well im will send you the accident reports onn the Stratos and the Winto sportsman aircraft both of whom I tried to stop causing repeated fatal accidents and produced reports detailing the engineering failings BEFORE hand (including the newspaper reports --one shows the split second before impact of one fatal Sportsman crash that also shows the glaring problem inn the aircraft'd basic layout )be

better end and send before this drops out ..

#### Synergy

##### Well-Known Member
Ross, I'm sorry to hear your plight. Hang in there. If you send a PM my way, we should set up a time to chat for a bit. I'll tell you a few things confidentially that you may find helpful.

The support from family, friends, and volunteers has been sufficient to preserve and advance our work, but as to the conclusions you've reached, about anything and everything I'm doing, and how- they just make me wonder in astonishment. Suffice it to say that to this point you really just have no idea about me at all, nor what it has actually required from us, nor anything whatsoever about our business.

Why do you therefore insist on talking about things you don't have any facts about? It seems so unhealthy, given your passion and knowledge.

Have you read my post #659? The seed of an opportunity is in there.

Please write about what you know, and do so professionally. Making myself or this project a symbol of any injustice you've experienced just isn't fair, honest, or accurate.

#### Aircar

##### Banned
John-your piece has popped up after my second installment --if you want to talk with me off site that is fine or email me --(And I haven't ever 'concealed' my identity as implied either ) rossnolan@optusnet.com.au --do it quickly as I might not even be able to keep the net going --my exboarder not only wiped four years worth of emails but files and links to data etc and left me unpaid bills (from playing"world of warcraft' for endless hours ) plus a cost of maybe \$2000 to ,maybe,retrieve some of it --the documents and any previous work I have ever described are all provable from published ,hard copy,verifiable, in print and by photographs.

Just to reiterate - I WOULD like to see your aircraft fly and do so properly and safely -it looks a lot more modern than 90% of the airborne antiques that are in the air now and will presumably have a market at the comparable sort of price to those things now available to the small cadre of well heeled and patient enough pilots who build this sort of thing but that is not what you are offering and as far as the engineering goes I am not 'agnostic' --or undecided, I just do not believe ,based on simple evaluation, with figures, that it will be any improvement over the similar looking contemporary aircraft or those much earlier (eg velocity,FS28 etc --all of whom could have elected to use BLC and the other ideas like laminar flow etc that are stock --the real low drag suction wing work was done in the late 1940s and very early fifties IN Australia with the GLAS 2 suction glider (which they,wisely, converted from a surplus WW3 troop glider to save costs and TEST the wing theory --all the reports (that are public --some are not and still at ARL now DSTO...) have been cited but I could put up links to them again if you wanted. It was your notional 'mentor' dennis Bushnell, who estimated the trillion dollar market for one specific kind of aircraft --the 'Converticar' or flying car -- the most vilified and misrepresented type of flying device in all of aviation so you are dealing with someone not just case hardened to near destitution as a way of life (situation normal --if I can give the cat his daily "death retardant" and feed myself I consider I am doing OK )but one who has been through the mill in many other ways for a long time --none of this exactly is exactly Iwo Jima in terms of privation etc or like the slums of Delhi but the ramifications of one area of aviation --the low cost personal roadable aircraft CAN in fact go way way beyond the toys for the rich category . And a bit of privation and even persecution by your own government and others might in a perverse way actually help to fit one for the task --I like to think of Sergei Korolev, ex glider designer, who was condemned to a Siberian labour camp and only brought back when the soviets realized that he alone could create their space program --imagine being virtually condenmed to death and left to rot for years and still coming back to help 'save' the same country --a bit of perspective helps in these things.

#### gordonaut

##### Well-Known Member
Ross, don't worry about sending the report...I'll send you a SASE from Canada in a couple of weeks and you can stick it in the mail at that time...

Btw I feel for you getting shafted by all those people...including your dad ferchrissakes...you deserve better...hang in there and things will turn around...

Regards,

Gordon.

#### Jan Carlsson

##### Well-Known Member
Aircar, Ross?
Nice to meet you.

I don't want to show my real name here in public, so I stick to Jan,

If I understand you, you ask about if trim drag, W&B and stuff is included in my Synergy aircraft performance calculation?

First, I have not made a performance calculation on the Synergy, I don't have the data to do that.

Next first, the aircraft performance calculation in my propeller program is a large chunk of numbers, one example, it is using wing drag (wing Fo) variation with speed/CL, vertical and horizontal stab areas is added as an percent of wingarea. but trim drag isn't there, (but some fudge factor), making it very accurate, that is the yellow drag curve in the presented diagrams.
The purpose with my performance "estimation" is to make it user-friendly, that is very hard to do, it would have been very easy to make a software where you have to type in all areas and distances found on an aircraft. but then it would have been more like a airplane design tool then a propeller calculation tool.

After next first, The 32´aircraft I name as a normal aircraft is using the same wing area, span and fuselage measurements (about) as Synergy, just to see what it would perform if designer Mr Ben Dover would have made a normal aircraft. If John's Synergy don't beat that, we can all glut? (is that the correct word?)

Then to give the Normal aircraft a chance it need the same equivalent span as Synergy might have, it will make for some top speed increase, but as we know the induced drag is small at top speed anyway, maybe 2 mph better? (but at a low IAS at height ...)

Last first, the "Synergy" with a top speed of 310 mph isn't coming from information from John, it is the fictive top speed from Howard’s example with a specified L/D at a specified speed. I (me Jan) see that as the high end of expectations we can have, that’s what I think, And it was used by me in the propeller program's "known" in-data, that is what I use if I know what top speed an aircraft have with a certain propeller. The resulting math behind that Blue curve is somewhat simpler then the "estimation" don in the program, and use a fixed Fo for all speeds, only induced drag is altered with speed. But if we look at the graph with the 32`plane with both curves lined up, the small difference is seen only in the numbers, not on the curves, so it make no difference for the propeller design.

So why did I do this? I (me Jan) wanted to see if it is possible to reach the numbers said by Howard, I didn't know if maybe that Normal aircraft would have been just as good, Then I wanted to have something to look back to the day John show us all flight data from test flights ( HURRY UP JOHN, latex gloves on!)

I have not said anything about what to expect from the real world Synergy aircraft, It sure look sexy, The boxy wing from some angles I don't know!? I have a brother in law that like VOLVO 740, I don't.

The performance numbers I come up with, I think it will be possible to reach them or close too plus or minus. if top speed become (at 18k) something like 250-300 mph it is great in my view on this.

If it is safe and easy to fly and don't have any unusually habits it can be a success, and every one will be there to copy and make there own version of the synergy! meaning ! it is smart of John not to give out any information that can cut down on his lead into this design.

Last edited:

#### davidb

##### Well-Known Member
If it is safe and easy to fly and don't have any unusually habits it can be a success, and every one will be there to copy and make there own version of the synergy! meaning ! it is smart of John not to give out any information that can cut down on his lead into this design.
That makes sense of why John is holding back much of the specifics. Didn't he seem to indicate that he was also working toward having methods and proccesses ready to go for mass producing Synergy kits? The idea being if it proves successful, he could move quickly with the right business partner to bring Synergy to market ahead of would-be competitors.

Anyway, here's another question for John. I seem to remember one of the renderings of Synergy that had the control surfaces highlighted in orange. The same rendering had the tail cone in orange. John, is this a hint that the tail cone area will have some sort of movement or changing geometry?

#### BBerson

##### Light Plane Philosopher
HBA Supporter
Re: Synergy Aircraft - was it a "rope-a-dope" after all?

I think discussions about performance of an unproven new configuration are just silly. Especially since some new BLC of some sort is involved.

But the safety discussion of this design (or any new configuration) should be fully explored for the benefit of everyone that may get involved in this design configuration.
BB

#### FarmBoy

##### Well-Known Member
Re: Synergy Aircraft - was it a "rope-a-dope" after all?

I think discussions about performance of an unproven new configuration are just silly. Especially since some new BLC of some sort is involved.

But the safety discussion of this design (or any new configuration) should be fully explored for the benefit of everyone that may get involved in this design configuration.
BB

Definitely! Safety should always be the NUMBER ONE priority! There are many integral design details that place safety clearly at the top of the heap and I'm sure John would be happy to answer questions (within limits of available time, of course, now that completion is full speed ahead) that haven't already been addressed. Various shapes, integration of kevlar and kevlar composite blends in key areas, design load factors, integral ballistic parachute, etc., etc. are but a sampling of the structural safety factors that are part of this design in addition to the (scale and computer modeled but as yet to be full scale flight proven) flight dynamic safety advantages that could possibly shape future GA designs.

Also, I think performance measures are part of the safety envelope and discussion of comparable GA design expectations provide an excellent basis for determination of the efficacy of John's BLC integration (which regardless he has previously stated would not be utilized during any maneuvers which could affect flight safety).

FB

#### StarJar

##### Well-Known Member
the efficacy of John's BLC integration (which regardless he has previously stated would not be utilized during any maneuvers which could affect flight safety).

FB
And remember, it still has to be determined what are the safe manueuers, and what are not. John's answer is probably on the conservative side. Maybe it turns out that the BLC proves safe in more and more flight modes as the test envelope is explored. Might be it "ain't nothin' but a thaing."

#### Aircar

##### Banned
I have gone to great lengths to do exactly as BBerson describes --to deal with flight safety issues and to put aside any quibbling over performance and to do so exactly for the reasons given '"for the benefit of anyone who might get involved in this sort of configuration " --in the first instance that will be John (or rather his test pilot) and I have just spent quite a few hours on the phone with him as part of this.

Since the flight behaviour issues are in fact not specific to any named single aircraft and are part of a spectrum that includes generically similar aircraft that I happen to have been involved with in pre and post accident (fatal-no other kind is investigated here with 'unregistered aircraft" ) investigations --including the Ligeti Stratos and the Mitchell wing U2 (which is another swept wing with external downlifting 'elevons' attached to the wing with central gap) and the published figures on the Golschmied 'lifting body' mega airliner also with the box tail plus the Hall warren and several other counter swept dual wing configurations.

To respect Jake's request not to post anything further on this thread I would ask anyone interested to go to the Ligeti stratos thread to continue the safety related discussion .

#### Jan Carlsson

##### Well-Known Member
Re: Synergy Aircraft - was it a "rope-a-dope" after all?

I think discussions about performance of an unproven new configuration are just silly. Especially since some new BLC of some sort is involved.

But the safety discussion of this design (or any new configuration) should be fully explored for the benefit of everyone that may get involved in this design configuration.
BB
Silly or not, this is a new concept aiming for better performance then older "normal" concept, so it is naturally that every one is having thoughts about what the actual performance will be, we have now showed what the normal configured plane would have, I (Jan) also showed what can be don to increase performance on a normal plane if we are careful in its construction, and how easy it is to destroy its potential. The performance of the Synergy prototype will we see after it have flown for some time, so yes it is silly to continuo that discussion until we know more.

But we can all learn from the clean lines of the Synergy or from just any pure modern glider plane, There was a Shaw Europa, I think it was built in California? that showed lot better performance then the rest due to attention to detail’s. like leaks and caps, I don't remember how much faster it was, but it was several 10's of knots faster. The same was to read about one in Europe, also with a Europa that ferry it over the Atlantic, by just tape the wing/fuselage gap it made 10 knots. "All" glider pilots know this, but there is a lot to learn still.

Last edited:

#### Himat

##### Well-Known Member
Re: Synergy Aircraft - was it a "rope-a-dope" after all?

A few of you, in between personal attacks and other bad behaviors, asked John for some actual numbers at which he is aiming for his Synergy airplane, now in construction. A few (some overlap with the first group?) asked for metrics so that success or failure could be measured when, at last, flight data would be available. That was to include some way of "knowing" if and to what extent the six synergistic design features were working. It was even demanded that it be compared to the Lancair IV-P.

I took the time to re-state in simple, workable, mathematical form, some of those answers. John cooperated and helped me make that work-up as good as it can be at this stage. It provides a minimum performance target that was originally revealed as a requirement for being a contestant in the GFC. It then provides a correct calculation of what those numbers would mean at other flight conditions if the airplane were conventional. Synergy can be compared to others on the first and to some of its additional features on the latter. Any assumptions were both explicit and reader-modifiable because I provided working spreadsheets.

So the result, simply stated, was that Synergy, for the GFC, expected to perform, aerodynamically, significantly better than the two electric motor-gliders that placed first and second with unprecedented PMPG. The follow-on result was a conventional calculation for FL 180 and 20 more available HP against which Synergy could be compared a second time and way. You asked for it. You got it.

And everyone either ignored it or mis-read it.

I'm sorry, but that's just wrong.

We now return you to the WWWF in progress.
Browsing through the thread again I do see that I should do some reading and check out the background information on your spreadsheet. And in the quest for performance metrics on the Synergy airplane maybe other's should do it too. To just measure is no good when doing physical experiments and in many senses the Synergy aircraft is just that. (Do the airplane have a name or is it just Synergy?) To be of any scientific use the measured data must be compared to a mathematical model, and that is as I see it what you offer. A mathematical model on aircraft performance based on known state of the art. And to measure against a mathematical model provided and documented by a third party is reassuring to outside observers. The chance is then greater that the mathematical model is not "weighted" in a favourable way. If now Synergy do not match the predictions in the model (the measuerements are inconsistent with the model) , John might have expanded our knowledge.

#### davidb

##### Well-Known Member
From reading John's update yesterday on the Kickstarter project page, it seems we have a rough idea of the time frame we can expect to see it fly. Sounds like he has a busy summer of getting the big pieces together and having it on its landing gear with the engine installed by this fall. I gather there is a lot of work still to be done after that but he hints at Oshkosh '13.

Gosh, I don't know if I can endure another year of speculation. Godspeed John.

Status
Not open for further replies.