# Synergy Aircraft

Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by Tom Nalevanko, Apr 30, 2011.

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1. Apr 30, 2011

### Tom Nalevanko

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BuildingSynergy | SlideRocket, Online Presentation Tools

What do you all think?

Synergy discussion @ HBA
Synergy discussion @ Oshkosh365
Cafe Green flight challenge website
EAA news reveals Synergy project

Some specifications:

Overall Length: 21 feet
Wing Span: 32 feet
Wing Area: 156 square feet
Gross weight: > 3,100 pounds
Competition weight: 2400 lbs
Empty weight: < 1,650 pounds
Power: 180-hp two-stroke V4 turbo/super diesel Delta Hawk
Cabin Width, interior: 56 inches
Gear: Tricycle, retractable
Minimum flight speed: <55 KIAS (dirty)
Range: >1,500 nautical miles w/std reserve

Synergy video

Last edited by a moderator: Mar 20, 2019
2. Apr 30, 2011

### Mac790

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3. Apr 30, 2011

### Tom Nalevanko

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This is the first presentation of the flying model; I believe. And a nice view of the construction...

It is really somewhat of a flying wing. Interesting concept!

4. Apr 30, 2011

### berridos

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It looks a little unstable at landing as a model. Should have a small cg range.
And somehow I dont like the guy whos talking...

5. Apr 30, 2011

### Voyeurger

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How about Bill Gates, do you like him? Are you a PC or MAC guy? The proof'll be in the pudding. Assuming all is as promised by the test data of the first flight, will you be able to like the product regardless of the man? OF COURSE! Give the guy a break. He's gone balls to the wall to launch this project. He deserves every consideration. IMHO.
Gary

6. Apr 30, 2011

### Bart

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Fair enough. John took some heat on this forum from some folks including me, for not disclosing specifics on his new design despite discussing it for quite some time.

Now that he's publicly putting cards on the table, I have much greater appreciation for the plane, and wish him full success.

7. Apr 30, 2011

### orion

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Difficult to establish any handling opinions from models simply due to their scale and the flying environment, and of course the skill of the RC pilot. Making that statement just by looking at one RC landing is probably a bit unfair.

Regarding the aircraft's CG range, yes, a first glance might suggest a narrow allowable range due to the short coupled nature of the layout however, remember that this airplane does not use flaps and as such is not penalized in a way that a more conventional layout might be.

Given the scope of this development and the combination of technologies they are employing in the work, I'd suggest giving them a fair chance, rather than criticizing based on the briefest of glances.

8. Apr 30, 2011

### berridos

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I was just kidding. (still remeber the old thread)
I understand their enthusiasm and a appreciate a nice design with innovative ideas.
However they should let the plane talk and dont be that aggressive in their marketing statements. 80% drag reduction? Compared to what? Any wind tunnel data comparing the plane to a piper cub?
The plane has plenty to say (factual) and is really overshadowed by unserious/pedant marketing.

Last edited: Apr 30, 2011
9. Apr 30, 2011

### Voyeurger

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Berridos,
I agree that, based on history, lofty claims are off-putting. BUT, the unfortunate reality is, that they need investors. Imagine putting everything you've got and ALMOST being there, and needing just a few more things ($10 or$20K). Their marketing, I believe, is only to lure investors, and involuntary. And likely as repugnant to them as it is to you.
Regards,
Gary

10. May 1, 2011

### Workhorse

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I admire everyone's endeavour for pursuing precision. His words are at least backed by hard work. I see a thinking work, a built shop background and these are just not theories.

I'd be interested in listening to his model flying with zero power or idled.

11. May 1, 2011

### Synergy

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Hi everyone. Thanks for your comments. Just a clarification, the video was a mandantory requirement of all competitors in the GFC back in August, and both EAA and CAFE Foundation requested permission to use it because they liked what we said and did in it. We had to say no for many months, and there are things about it that we don't like outside of their original (limited) context. But it is better than anything else we have right now.

I think if I understand Topaz correctly, everything is marketing, but there is nothing for sale here. I am just trying to build a cool airplane based on some things I've spent a long time refining. I already know that cool airplanes are what we all like, and if this all works out we'll get to earn a living from it. That's the dream, anyway. It's harder than most of us are willing to find out.

Thanks again guys. I get back to work Monday so if anyone wants to interact with me now is a pretty good time (after my nap, anyway. 21 hour day yesterday, four hours sleep).

12. May 1, 2011

### Voyeurger

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Heck yeah I want to interact with you! I just got in, so I'm a little late.

John, seriously, how far away is first flight? Have you installed that hot new diesel (Deltahawk?) in it yet? All made up and being assembled? Please don't give me the old 90% saw. 30,60,90 days? Where's final construction and taxi tests to be done?
If you will answer any 3 of the 5 questions above, I would be very happy.:gig:
Thanks,
Gary

13. May 1, 2011

### Synergy

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1. six weeks
2. No
3. No
4. KGPI

Count again, Gary!

OK, people, completing this project on someone else's schedule utterly depends upon being able to fund it. We are 100% committed to completion and it's presently worth \$24,000 a day to us to do so. Without some tiny fraction of that being available in advance, we will all just have to wait. This is FYI because I have been on the record about this need from the start, and anyone who wants to get on my case about the schedule ought to at least have bought a T-shirt to ask.

14. May 1, 2011

### berridos

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My subjective opinion:
I would have tried to do the wing tips rounder to reduce the interference between the horizontal and vertical surfaces.

15. May 1, 2011

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I think there's a cultural background in that too. US marketing is vastly different from what we see here and honestly, if I'm looking at the ads of Cirrus or Lancair, I get the same feeling.
Yepz, those 80% seems implausible (if you "benchmark" against a Cirrus 22 for example). But let's face it. This is one of the very few places on the internet where we can actually talk about design and where everything, different then a spamcan isn't immediately rejected or laughed at. It looks like most people (pilots) lack the knowledge, the interest or an understanding about actual aircraft design. Thus, it's not necessarily unwise not to talk too much about that, simply because the big majority is more interested in other things he does discuss.

Regarding the design; I like it. Some criticism:
*Retractable landing gear? I think many have made (and proven) a good case for welded-down landing gears. Lots cheaper to develop too I would think, not to speak of insurance for pilots.
*The tail. I follow (or think I follow) the reasoning behind a "fat pod" and a Prandtl wing, but I would suppose that a continued upper "wing" has lower drag and weight, compared to this configuration and a structural advantage too. Is that correct?

Last edited: May 1, 2011
16. May 1, 2011

### Autodidact

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That is very impressive any way you look at it. The phrase "pressure recovery augmentation" keeps popping into my head; I don't know why - it just sounds cool... :grin:

17. May 1, 2011

### Inverted Vantage

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Nice looking design. I'd be interested to see some more detail on the ailerons up top.

18. May 1, 2011

### Tom Nalevanko

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John, best of luck to you as you run down the homestretch. It can come together faster than you think, particularly if you just shoot a few naysayers; LOL.

If you have the time I would appreciate some words on your approach to engine cooling and also scalability of the design.

I like the fact that it is a retractable. Some of the arguments against on the forum are just plain silly and largely based on fear and the assumption of dumb pilots.

Blue and big skies,

Tom

19. May 1, 2011

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Not sure whether you're referring to my post, or that the above sentences are unconnected, but the facts are clear:
*Insurance of an RG is more expensive and quite a bit too.
*RG is heavier compared to FG
*RG's for homebuilts are a lot more labor-intense to build
*RG's are way more expensive, homebuilt or factory-built
*RG's are less reliable, simply because they have more failure modes compared to FG

Yes, there's something to be said for retractable gear (speed isn't a major one of them imho), but I think that - especially for the market where John is going for - RG is a surprising choice.

20. May 1, 2011

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