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JoeM
01-10-2012, 11:03 AM
I will be going to Sebring next week to help decide what kit I would like to build. I am looking for your thoughts and experiences on things I should look at to help my decision. The aircraft that meet my mission are the RV-12, Zenith CH-650 and the Sonex. The factors driving my decision are useable load (I am fat, 235 lbs), ease and time of construction, and I need to be cost conscious. I will be a first time builder and am still a student sport pilot. Following are my current observation:

RV-12.
PROS: Looks like the easiest to build with everything included in the kit and match drilled parts
The support of many in the VAF world.
CONS: Don’t care for the Rotax, would probably go E-AB with the Jabaru 2200.
Don’t care for the flarerons, prefer standard flaps.
Vans does not support any changes to their perfect design. It says so in one of the first pages of the instruction manual.

CH-650:
PROS: Best looking of the three.
Wing fuel tanks.
CONS: Seems to be more fabrication, skins not cut to size and parts not match drilled.

Sonex
PROS: Built to exceed LSA speed rules, wider safety range in structure strength.
Aerobatic. Not really important but the ability to do a few barrel rolls could be fun.
CONS: Lower Gross weight.
Interior doesn’t look too comfy, but I will find out at Sebring.

David Darnell
01-10-2012, 01:39 PM
Well, A couple of thoughts regarding your choices.

RV-12- Yes, lots of builders support from the VAF - certainly a positive factor IMO
IMO hard to tell the difference between it and the 650 (visually, that is)
Not entirely sure I like the "my way or the highway" with regards to the design. However, I can relate to need to limit things with all the copycating and liability concerns.

Zenith 650- Like the fact that they have the builders workshops where you can get a feel for it. Also its my understanding they have a distributor a couple of hours from you in Lakeland- if you run into a "gotta have" you should be able get the part fairly quickly.
Like the fact that you have several engine choices, from the Corvair to Lycoming O-235
The wing issue a couple of years ago have me somewhat leery about the Zeniths. Hopefully they have it resolved, but IMO too soon to tell

Sonex- Probably the one I have done the least research on.
I'd really be concerned that you would be pushing gross weight fairly quickly. Looks to me that it has the lowest GW and payload of the three- factor in the fuel, baggage etc, you would soon have a single seat.
Do like the variety in engines
Imagine it would be snug to fit in- close dimensionally to the Cessna 152

CarlOrton
01-10-2012, 01:51 PM
Hi, Joe;

HooBoy, another Ford vs Chevy thread! OK, so here are my opininions, and they're just that.

I am currently finishing up a Sonex. It's 99.9% complete, but since I'm still finishing my tailwheel endorsement, I'm using the time to paint the fiberglass and polish the skins. The costs advertised on the Sonex website are pretty close to being dead-on. I went with an Enigma color EFIS, the microAir comm & xpndr (I'm under a Mode C veil), so my costs are a bit higher, but right in line with what they say. I'll have bout $33K in mine when complete. Other builders state that the performance is dead-on with what Sonex says, as well.

I helped my neighbor build an RV12. He has about $60K in his, and like you say, that's w/o options (and that was before he paid to have it painted.). EXTREMELY easy to assemble. Pull out the parts, cleco, rivet, and you're done. I think each wing took him about 1 week. Very nice plane; I fly it regularly. He flew it to AirVenture 2010 with 7 (no typo) hours TT on it (ELSA only have a 5-hour Phase I checkout). Flew it there last year as well. Hopefully we'll have a flight of two (my sonex) for 2012. Decent performance; about what my 172 did.

I have the least information on the Zenith. I guess it's because I just haven't had any close contact with any. If there's a bunch completed, they don't show up at fly-in's is all I'm saying (flames begin).

The main reason I chose my Sonex was support. Let's face it; a bunch of a/c and kit manufacturers have gone under. Do you want an orphan? While I doubt that any of the 3 you're looking at will fail, nothing is impossible in these interesting times. With Sonex, I have every single dimension contained within my plans; the others are assembly manuals. Need to build a new part for, say, a bird strike? I can. Sonex (and Van's) tech support is great; I've never had more than 24hrs go by w/o an answer from Sonex themselves (I can also call if need be). My main source of help, though, are other builders. There are several Sonex discussion groups, similar to VAF in nature, where you can post a question and get all sorts of responses. The last time I checked (many years ago), I believe that Zenith depended on the Matronics news feeder; never saw much traffic there. Things may have improved by now.

The Sonex is tight; I'm bigger than you, but my wife and I can fit in there. We had shoulders touching in my 172; the dimensions on the Sonex say that it's about the same, but it is a bit tighter. If she rests her left arm on the crossmember behind the seat, it's much better. With any of these 3 planes, unless you wanna get hard-nosed about it, you will want to land after 2-3 hrs just to stretch.

As with any plane selection, you have to know your mission. 95% of mine is solo flight just to have fun. I bought the plane to fit my mission. That's not to say that it's not a capable xc machine; Phil Simon hit all 48 contiguous states in his; Kerry Fores (Sonex Tech Support) has made numerous flights from OSH to SnF in his. Many others share similar excursions; one guy has even made multiple flights to the Bahamas in his.

As builder, *you* determine what your gross weight will be. Just cause Sonex says 1100 lbs doesn't mean you can't change it. Now, don't get all stupid and try 1500 lbs or something like that, but I know several builders who've taken theirs to 1200 lbs. I'm building mine to 1150; that will allow full fuel with my wife on board. Will it be a dog at that weight? Sure. Will it be safe? Should be (I say that only because *I* haven't flown it at that weight yet.)

Lastly, I, too, felt strongly about "no Rotax." Funny what a little experience;knowledge does to one's opinions. I think it's a great powerplant. The US support side appears to have their act together quite well; lot's of training and parts available.

Have fun at Sebring!

Dave Prizio
01-11-2012, 10:45 AM
The Vans RV-12 admonition against changes is there because the -12 was originally concieved as an E-LSA which by law requires total compliance with the original design. Now that it hs been approved for experimental amateur built status it no longer has to comply with the E-LSA rules.

Do you homework on the Jabiru before you get too excited about it. There is a Yahoo forum dedicated to Jabirus that is worth exlporing if you are really thinking about going that way. The engine definitely has some quirks to it that you should know about.

There are good reasons why Vans sells more kits than everyone else put together, and there are good reasons why Rotax engines power more LSA airplanes than all the other brands put together. That is not to say that you should not consider the alternatives; it is just to say that you should not be in any hurry to discount the collective wisdom of such a large number of people.

Dave Prizio

Dwight Nicholas
01-13-2012, 09:03 PM
We are approximately 40% through a RV 12 construction project. Plans are good, support from Vans has been great. The couple of parts I have needed (failed to read directions carefully) they shipped the same day I ordered them. I am still amazed at how well EVERYTHING fits. It is truly a giant erector set. Currently we have 325 hours in it. Tail is done, vertical and horizontal stabilizer is done, Rudder is complete, wings are complete and the fuselage is about 50% complete. Ordered our finish kit this week.

I was a little concerned about the Rotax (something about cruising at 4900 RPM) but after talking with what I believe were a number of qualified folks, I believe IF you maintain the engine as specified (at least 70% mogas, use the correct oil and make sure the oil temp is up prior to taking off) it will be OK . Most manufacturers are using it so you would have to wonder how Rotax dominates the LSA market if they really were a problem. VANS has never used anything other than a Lycoming in their other planes and they chose the Rotax for their LSA.

We looked at the Zenith 650 and the Jabiru. The Jabiru has had some past problems of engine overheating and I was a little skeptical of the composite from both a construction and maintenance standpoint. The engine looks really nice and was EXTREMELY smooth when I flew it. It was an impressive flying plane.

I liked the 650 but the past wing issues (although they claim the problem is solved) were a little concerning.

I also liked the Breezer but the lack of US built kits was too risky.

Vans is extremely conservative but I believe that is one reason they have been so successful- NO surprises! Although we are not done, to date we have been extremely pleased with our decision. I flew it 3 times before we purchased and every time it was amazing how stable and forgiving it was. My only real heartburn with the RV12 was the lack of a steerable nose wheel which I will just get over.
Dwight

Jim Hann
01-15-2012, 01:49 AM
Vans does not support any changes to their perfect design. It says so in one of the first pages of the instruction manual.
JoeM,

That is the mantra of every designer of homebuilt aircraft and probably a lot of other things also! Their biggest concern is a major alternation with out sufficient engineering to maintain safety and integrity of the design. (Just check out and old Canard Pusher for Burt Rutan's comments or a Co-Z newsletter for Nat Puffer's).

The RV-12 is now approved by the FAA as a "major portion" E-AB kit, so you can do what you want as long as you don't have commercial assistance that will take you below 51% of "the work" however they are defining it now.

Jim

JoeM
01-20-2012, 12:46 PM
Thanks for all of the replies. I visited Sebring yesterday and got to look over two of my three choices. I tried on and looked over the CH-650 and RV-12s with both the Rotax and Viking engines. Both the RV and the Zenith felt about the same to me for comfort and ease of getting in and out. I did not see anything to dislike about either one. I will definitely get a flight in both before making my final decision. I will say I am leaning towards the CH-650 for the option of building as a taildragger and the wing fuel tanks however these things are not dealbreakers. Sonex did not have anything at the show.

Frank Giger
01-21-2012, 02:24 AM
The "no changes to the plans" becomes a big plus when one goes to insure an RV, though.

Insurance companies like the track record of RV's versus other experimentals because they're a well known design and build, and premiums reflect it.

Eric Witherspoon
01-21-2012, 04:22 PM
Sonex did not have anything at the show.
They just announced they will be sending a couple of people (company principals, actually) to Sun N Fun to present some forums and host a builder's party. You should be able to see some of their aircraft over there. They have not traveled much since 2000-2001 timeframe, when they experienced a highway accident on the way to Sun N Fun - smaller company like that can't afford to lose that much hardware, even if it is insured (company airplane much damage & trailer destroyed). They are based in Oshkosh - so not only can you see all their airplanes there, plus some prototypes that aren't for sale - you can also go across the field to see the factory (see their website for how they work this during Oshkosh - probably a couple of limited "tour" times only, but it is right there). Builders of the Sonex designs also put together multiple regional gatherings each year. In your area - I believe there is one in N or N central Fla. There's also Tennessee, possibly 2 in Texas, Nor Cal, New England, and probably others. I'm just 22 min by air from Copperstate, so I've brought mine there for the past 3 years. Plus on their website, go to builder resources, find builders, enter your zip code and the distance - will tell you who owns/built one in your area. So no real reason not to be able to find one.

Anyway, you've brought up this "wing tanks" thing more than once. Here's a little information you may not have considered:
Wing tanks require pumps. Pumps you not only have to buy ($) and install (weight), but keep leak-free and running all the time (in areas that may normally be out of sight). Almost universally, this will mean backups - more money, more weight, more leak paths. Wings also can take up a lot of energy in a forced landing. I've seen several "Sonex on ground" photos where the wings run through fence posts & sign posts where the occupants walk away. As I was doing some rapid roll exercises this morning - wing tanks add inertia to the wings, slowing down the roll rate for a given airframe. They also negatively impact spin recovery - not that a spin wouldn't be recoverable, but with lower-mass wings, the spin is quicker and recovers quicker. There also will be traps in a wing-tanked fuel system for water or other contaminants. Can't avoid it - tank lower than engine, there's a trap in there somewhere.

The Sonex in-fuselage tank:
Has no pumps. If there's fuel in the tank, it will fall into the engine (ok, so long as you keep pos-g on the airframe;)).
Has no traps. On my installation, the carb is the low point. So if it doesn't start, there could be water. Once it does start, there will be no more water.
Can be inspected. I can see everything in the firewall-aft portion of the entire fuel system by looking under the panel. There are no hidden parts.
So an in-fuselage tank is lighter, has lower roll inertia, can be inspected, doesn't require pumps, and may be less likely to get blasted open on a forced landing.

To Frank's point - nobody with any of the insurance I contacted asked anything about "no changes to the plans". To my experience, that's an urban legend. Though with any of these three designs, they are well known, there's bunches of them flying - so insurance issues / non-issues would be about the same for all of them. If you're low-time, they're gonna charge more. If you have zero time-in-type, they're gonna not cover you until you do. Of these three, the Sonex is the ONLY one (by virtue of its lower gross weight) that can be insured from zero time via "ultralight" insurance. UL insurance has two big disadvantages to be aware of - first, no pax liability. You injure/kill the guy in the right seat, it's your problem (but during the 40-hour Phase I flight test period, you're not going to have anyone in that right seat, and by the time that's done, you're going to have 40 hours in type...). Second, no hull. As "ultralight" insurance, they assume it's an "ultralight" - cheap enough for you to assume all hull risk. On the plus side, you pay your money, you have the liability your airport requires to get a hangar...

Here's another hint that could get you a Sonex ride - go to Yahoo Groups, join Sonextalk - ask over there. Probably a couple of people not too far away that could at least give you a look, if not a ride. I also second everything Carl says - highest performance for the money, especially among these three.