4 seat, twin engine, low wing

[fdeppieri]

Hi all,
This is my dream. I was thinking to start from RV-10 kit, redesign several things. I do not find anything else that looks like want I want to build. Velocity V-twin is too expensive. Any suggestins? thanks a lot! Francesco

[Kurt Flunkn]

Buy a Piper Apache .....twins are very cheap now due to demand and operating costs.

[1600vw]

The other day I went for a flight with a friend out of Lincoln airport or Logan Co. airport. Across from my buddies hangar sat a twin engine airplane sitting out in the weather. From my understanding the owner stopped paying hangar rent a long time ago and the FBO moved it out of the hangar.

[Auburntsts]

There are a couple of RV "twin" projects out there. Unfortunately the Duo Deuce (2nd link below) was crashed during a taxi test that ended badly after inadvertent flight followed by an engine failure occurred-- the pilot was hurt but she's recovering. Anyway, you might want to contact either or both to see what's really involved in such a project. As an RV-10 builder I can tell you the amount of work will be monumental at the very least. If you're into the challenge, aren't interested in getting into the air quickly, and money is no object, it would be an interesting project! However, if flying is more your thing rather than building, as the other posts have indicated, it would be way cheaper and easier to buy a used twin.

http://eaaforums.org/showthread.php?4241-Updated-photos-of-Twin-JAG

http://www.vansairforce.com/community/showthread.php?t=142015

[fdeppieri]

I have a clear idea between buy and build, and the decision has been done. I like the right words "monumental work"; they are somethings familiar in my life, for several other past projects...
So the main question is only related to the best way to see the dream realized; more or less within 5 years. I'm not sure the RV-10 can be the best starting point. For the point of view of the final goal, there are some common points, even I suspect the modifications could arrive to a much different design. I try to look some other "old" plans but I never find something able to convince myself. For sure, before to put the first rivet, I want to print the complete design, simulations, analysis etc. It is possible to do. This means at last another year before the building phase. This is the main reasons I posted this question. Thanks to all for any ideas.
I already knew the couple of threads about "twin", and for sure I will contact them for more info about.
Francesco

[Auburntsts]

Just FYI--the RV plans aren't plans in the traditional sense. They are assembly manuals. As such they don't contain engineering drawings with dimensional data.

[Kyle Boatright]

Just FYI--the RV plans aren't plans in the traditional sense. They are assembly manuals. As such they don't contain engineering drawings with dimensional data.

Which is frustrating as hell for this RV-6 builder with an RV-10 in the shop. Dimensioned plans would really be helpful from time to time.

[DaleB]

RVs are wonderful airplanes, but as noted the plans are not intended for scratch building or even for engineering alterations or modifications. The only dimensions given are for parts that need to be fabricated. If you intend to do heavy modifications to an RV kit, you'll have to start by doing all your own measurements.

I suspect the reason you can't find what you're looking for is that you, as someone who wants to build a 4-place twin, are part of a very, very small group. Nothing wrong with that, I find myself in the same boat from time to time. But you'll find that if you move forward it will be with a machete and axe, blazing your own trail as virtually no one has been there before.

[martymayes]

Just FYI--the RV plans aren't plans in the traditional sense. They are assembly manuals. As such they don't contain engineering drawings with dimensional data.

I had a set of RV-4 plans that had the necessary data to build the plane from scratch. I sold them about 2 yrs ago. May have only been an option with the -4.

[Auburntsts]

I had a set of RV-4 plans that had the necessary data to build the plane from scratch. I sold them about 2 yrs ago. May have only been an option with the -4.

Possibly- can't speak to the 3 or 4. I'm pretty sure that 7 thru 14 don't have that data in their plans beyond required parts fabrication as already mentioned. The 10 definitely doesn't.

[Kyle Boatright]

Possibly- can't speak to the 3 or 4. But I know for a fact that the 6 thru 14 don't have that data in their plans beyond required parts fabrication as already mentioned.

The -6 does. The kit came with about 50 large scale blueprints and a 20 page manual. The manual was pretty detailed through the empennage section, but IIRC, it went through the entire process of wing, fuel tank, flap, and aileron construction in 2 pages in the manual and about 15 pages of blueprints.

Good or bad, you either looked ahead in the build or did a lot of rework at some point...

[fdeppieri]

Thanks for the clarifications about the RV plans. I understood they are more or less just some “assembly manuals” and so it is very difficult to use them as starting point for a different design.
The option could be to create a complete model from the real kit, even this means to buy all different sections before to do anythink; and this is what I’d like to avoid. I’d not know if it is possible, but in the short term I will be at Vans Aircraft to understand personally what it is possible to buy and get in terms of useful data. Does anybody have some experience about that?
As said, the other options was to find an existing plans (ex. Cessna 310) but until now what I found are much different from the original personal preference.
Francesco

[FlyingRon]

The crash of the Duo Deuce mentioned earlier was my old mechanic Bobbi Boucher. My wife has talked to her a bunch of times after the crash. Lost an engine on takeoff. I've flown in her earlier RV-4 build.

[Sam Buchanan]

...in the short term I will be at Vans Aircraft to understand personally what it is possible to buy and get in terms of useful data...

Do not be surprised if you receive a less than warm reception at Vans after you explain the purpose of your visit. ;)

[Bill Barker]

You might contact Zenith Aircraft (USA) or Zenair (Canada).
They have a prototype 2 seat low wing twin. They also make the 640, a low wing four seater.
Maybe they will give you some insights. They encourage experimentation much more than Vans does.
Good luck.
P.S. I double checked and Zenair (manufacturer of the 640) does include their blueprints with the kit, as well.

[fdeppieri]

Thanks a lot!
I suspect there are not so many ways to get useful data to realize the dream. Anyway this is not a good reason to avoid to make some attempts.
The twin Zenith prototipe is dated 1996; maybe they could be interested that someone try to make some other invesigation about.

Francesco

[Auburntsts]

What is your flying mission and subsequent aircraft design goals?

Also something you need to think about is insurance, which depending on your ME time might be unobtainable.

[fdeppieri]

I know insurance could be a big problem. Anyway, at the moment it does not effect the technical feasibility of the project. One step per time, even the road is very, very long.

F.

[rhbelter]

Ahoy, Francesco,

I did two pieces some time back in this forum, about a suggested 'push-pull' twin to aid the development of alternative engines. Pretty much fell-flat. I'm a retired TailHook Naval Aviator, am very familiar with asymmetric thrust, and the serious handling challenge it induces. I strongly suggest that you look at the Burt Rutan 'Boomerang' for inspiration. I've looked at it in a casual way. The articles which discuss the result show that that the concept has considerable merit. It probably could be somewhat simplified, be built in metal, and retain most of the benefits. Enjoy /s/ Bob