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RV-12 Alternative

Surface Warrior

Surface Warrior

Member
Has anyone done any research on the Sonex? Thinking this might be a good alternative to the RV-12 because it is approved for aerobatics and accepts 3 different engines. The Jabiru 2200 (80hp), Jabiru 3300 (120hp), and a kit built 80hp VW variant engine.

Sonex website says all three meet the LSA rules. Although, it states, the Jabiru 3300 (120hp) meets LSA speeds at Sea Level. It cruises at 170 mph at altitude.

Anyway, I was reading the November issue of Motor Trend, and on the cover, they compared two sport coupes with the following statement, "150 mph, under $25,000, and 28 mpg." And I thought, wouldn't it be great to have an LSA that meets these parameters. Much more fun to fly than drive, and if you can roll/loop along the way, even better...

Well, the Sonex with 80hp will cruise at 150 mph, under $25,000 (including the 80hp kit engine), and 27 mpg. Sounds like a flying sports coupe, and an alternative to the RV-12, and as a bonus, the Sonex is approved for aerobatics.

Any thoughts?
 
Sonex

I am comparing several kits, the Sonex being one of them. I have not flown in one yet - so can not attest to any qualities there. There are at least a couple folks here on the board who have flown in and/or owned a Sonex which could speak better to that.

My only observations after looking at them, and talking to owners are as follows:
  1. Small plane - Small cockpit! Your needs may vary.
  2. Subjective opinions vary widely about its appearance.
  3. Positive reputation of its manufacturer.
  4. VERY economical build - especially if you go with the AeroVee.
  5. Reputation as being a fun flyer.
  6. I've never heard anyone badmouth anything other than the appearance of the Sonex. (see number 2 above).
I am fortunately (??) not in a position to make a decision/purchase for another year or so... and thus am waiting for the RV-12 and S19 to be flight tested and further developed. Then I will make the rounds and try them all out in the air before making a purchase decision. (I'd be happy to fly in anybody's plane at anytime... but don't plan to really "test-drive" until I can arrange to do them in a narrow time frame - so the experience of each is fresh).

A deciding factor for me will probably be the availability of a quick-build version. (Sonex does not currently offer one). Once I start - I hope to be in the air in 18 months. Then, I'll probably start an RV-9 (or 10) on the 5 - 6 year rivet-bucking program.

They have a site on Yahoo which is accessible from the Sonex Mfg. webpage. I hate Yahoo boards - but there is some good info there. Of course all the sites pale in comparison to Doug's site here. The reputation of Van's and the SUPER strong support on this page is another factor in my waiting for the RV-12 to come out. You can't put a price on the value of this site and the great folks here.

Don't know if this helps...

dj
 
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Unfortueately, as I recall, the Sport Pilot certificate is not approved for aerobatics :mad:

But, as an experimental, you would still be able to do them as a private pilot :confused:

I think......
 
ddurakovich said:
Unfortueately, as I recall, the Sport Pilot certificate is not approved for aerobatics :mad:

But, as an experimental, you would still be able to do them as a private pilot :confused:

I think......
Click to expand...
I haven't seen anything about aerobatics in the Sport Pilot limitations. You can't operate an aircraft contrary to it's operating limitations, so you'd need a Sport aircraft that is capable of aerobatics.
 
more Sonex

All the RV'ers at the local airport thought the Sonex was a bit on the ugly side, but after the first 200 mph pass with the Jab 3300 sounding like a mini-Merlin it got better looking real fast.

If you're interested in a LSA compliant aircraft that is capable of basic aerobatics and want to see what the Sonex will do, spend the big bucks ($5) and get this DVD:

http://www.sonexaircraft.com/choosing/rightseat.html

I owned one for six years and flew it 550 hours. For the money, you'll not find a better flying airplane. Had the building bug not bitten quite so hard, I would still have it. The current project is an RV-3B with the tail feathers complete and wing about 80% finished.

Tony
RV-3B 11395
 
Flying Qualities?

I have not flown a Sonex, but I owned a Moni. If you remember the Moni, then you know why I mentioned it. The Sonex looks like a Moni that got middle aged. John Monnet designed them both and the Sonerai series.

A friend flew a Sonex from Michigan to the west coast for someone else who was considering buying it. The return was done because the Sonex's flying characteristics are not tame. My friend is a very capable pilot, owned a Moni and a Sonerai, and easily adjusts to the aircraft. That said, if I understood him correctly, the Sonex will not fly like an RV. That's not necessarily bad, depending on your requirements and desires, but it's not a replacement for any RV and certainly not the -12.

It's a different airplane. Not better or worse unless you clearly define what you want from it. Think it through - my suggestion.
 
Wow that is something.

Tony Spicer said:
All the RV'ers at the local airport thought the Sonex was a bit on the ugly side, but after the first 200 mph pass with the Jab 3300 sounding like a mini-Merlin it got better looking real fast.

If you're interested in a LSA compliant aircraft that is capable of basic aerobatics and want to see what the Sonex will do, spend the big bucks ($5) and get this DVD:

http://www.sonexaircraft.com/choosing/rightseat.html

I owned one for six years and flew it 550 hours. For the money, you'll not find a better flying airplane. Had the building bug not bitten quite so hard, I would still have it. The current project is an RV-3B with the tail feathers complete and wing about 80% finished. Tony
RV-3B 11395
Click to expand...
200 mph! That's 3 mph over Vne. The Jabiru is 120 HP at 3300 rpm but only intermediately, normally 107 hp. Sound like he was showing off; hope he does not bust his tail.

The Sonex has been around for a while and has a good rep. It's a super small plane not tolerant of builders over indulgance in "super inst panels" from weight and space standpoint. Its a bear bone deal, which I like and think is cool, but its not comparable to a RV. I also think they like pull rivets, which I am not fond of, but I am not sure that's still true.

Bottom line how can a LSA really do 200 mph flybys. It sounds like it is too fast?
 
I also built and flew a Moni for a couple of years (see Sport Aviation May, 1995) and as for great flying airplane, it is. Cruise 105 mph on 25 hp, aerobatic and a 20:1 glide ratio.
But it does NOT fly like an RV. It is much more pitch sensitive. I have flown most of Monnett's designs but not the Sonex. So I can't elaborate on it.
 
yet more Sonex

gmcjetpilot said:
200 mph! That's 3 mph over Vne. The Jabiru is 120 HP at 3300 rpm but only intermediately, normally 107 hp. Sound like he was showing off; hope he does not bust his tail.

The Sonex has been around for a while and has a good rep. It's a super small plane not tolerant of builders over indulgance in "super inst panels" from weight and space standpoint. Its a bear bone deal, which I like and think is cool, but its not comparable to a RV. I also think they like pull rivets, which I am not fond of, but I am not sure that's still true.

Bottom line how can a LSA really do 200 mph flybys. It sounds like it is too fast?
Click to expand...

George,

If you really want to quibble about 3 mph I'll be happy to say it was really 197 mph.

I'm not real sure just how the comparison between the flying qualities of the RV and the Sonex crept into the discussion. It certainly wasn't me that made it. I've flown the RV-4, RV-6 and RV-6A as well as the Sonex, and would suggest that perhaps you should fly a Sonex before making a comparison. And don't forget that this thread got started comparing the Sonex to the RV-12. It will be quite some time before that comparison can be made.

You do not understand the LSA rule on speed. Nowhere is Vne mentioned. What is in the rule is Vh, which is the maximum speed in level flight with maximum continuous power. What is maximum continuous power for the 3300 Jab? The manufacturer only lists maximum continuous rpm. To see what that is, go here:

http://www.suncoastjabiru.com/Files/Engine Docs/3300/Instruction and Maintenance 3300.PDF

and have a look at section 2.7 on page 10 and you'll see that it's 2750 rpm. A 3300 powered Sonex equipped with the recommended prop will do 135 mph on a standard day at sea level. On the new 3300 equipped with hydraulic lifters that has been changed to 2850. On long cross-countries at 8000 feet or higher, I ran my 3300 at 3100 rpm all day long. Discussions with the engine designer indicated that at below 75% power, not much could be done to hurt the engine.

Want a ride in the Sonex? Just send me your address and I'll send you a copy of the DVD.

Tony
 
A few years ago my son was interested in the Sonex. I remember Tony Spicer's name as being one of the first Sonex builders. IIRC, there was a feature article on him in either Sport Aviation or Kitplanes magazine.
Tony, if your RV-3B turns out as neat as your Sonex, it will be a trophy winner. Glad to have you in our midst.
Don
 
DGlaeser said:
I haven't seen anything about aerobatics in the Sport Pilot limitations. You can't operate an aircraft contrary to it's operating limitations, so you'd need a Sport aircraft that is capable of aerobatics.
Click to expand...
Might have been something I saw before the rule was finalized.

That's the trouble with getting old, I can't seem to remember what I've forgotten :D

Or something like that.....
 
I have flown twice in a Sonex and fly regularly to fly-in events with a person that owns a Sonex with a VW engine. His plane goes at 125MPH or so because of the smaller VW engine. His ROC is bad with that engine and he does not operate from my 1100 strip with it, so the best bet would be the Jabiru 2200 if you like those engines to get good performance.

Here are the things that turned me off when I flew in my friend?s Sonex:

1. Visibility. It is pretty bad when compared to most airplanes I have flown. It also has to get into step to get good forward viz, meaning if you like slow flight be prepared to fly with high nose attitude.
2. Windshield rake and glare. You have to work hard to control it by adding dark colors inside. The Sun was murder going west on his plane.
3. Pretty small. I am 6?0 and 200# and the owner is 5?10 and 160# and we were pretty tight in there.

The brother of the Sonex owner bought a Sonex kit. After a few flights on his brother?s plane he decided to sell it and keep his current bird instead. I thought about buying the unfinished kit from him but decided against it and started an RV7 I found unfinished in my local area.

I am used to sensitive controls and that did not bother me much. The plane flew OK but it was too small for my taste and the visibility really sucked. Then again, I am used to fly a high wing pusher so I am very, very spoiled when it comes to looking out the window. Before buying an LSA a guy should fly both high and low wing to see what they like best. Cruising the country side at 1000 feet AGL @ 100MPH is done best without a wing blocking the view of the fall colors and such. For LSA type of flying speed should be one variable, and not THE variable. Visibility, STOL, GPH, Maintenance requirements, ease of build should be on the list too.

If you know Dave Goulet, you know the Challenger UL airplane. Many moons ago, Dave scratch-built an RV4 look alike with a Hirth engine using tube and fabric. That airplane exists today in my area with a Rotax 912S engine and the feathers of an RV6 I donated to the project in exchange for a set of wheels and brakes. With the Rotax 912S it does about 140MPH at 5200 RPM. I got wind from this year?s Challenger?s meeting that there is a strong possibility the plane may enter the LSA market fray. It would be a fairly quick build since the fuselage would be factory built and the wings would be almost complete. If you know Dave?s designs it would be a rib and fabric cover job mostly. Not sure what they would do about the tail feathers since Vans would not be selling them to them, I suppose? I?ll look for a picture and post it.

J Borja
 
Mel said:
I also built and flew a Moni for a couple of years (see Sport Aviation May, 1995) and as for great flying airplane, it is. Cruise 105 mph on 25 hp, aerobatic and a 20:1 glide ratio.
But it does NOT fly like an RV. It is much more pitch sensitive. I have flown most of Monnett's designs but not the Sonex. So I can't elaborate on it.
Click to expand...

Hi Mel,

When you inspected Sonex #664 you ask for a report after the flying started. Unfortunately I still don?t have a tail wheel endorsement. However, Kevin Ross (friend, fellow RV pilot, and former Moni builder) has volunteered to help me out with initial testing. I just got home from KMWL. Kevin put a solid hour on the N663SX today. He has had nothing but praise for the airplane. For the record, N664SX is a conventional gear, dual stick, AeroVee powered Sonex. Following are some of the comments Kevin has made.

?I can?t believe how smooth it is.?
?It flies like an RV.?
?It is very easy to land. Can you imagine how easy a tri-gear would land??
?It has no bad habits.?

Kevin was flying today at 3500 msl. I don?t have a clue what density altitude was but here are some rough numbers:

Mid-range cruise: 125 mph indicated.
Full throttle: 147 indicated.
Stall: 37 indicated.

I?m sure the stall speed wasn?t accurate due to the steep deck angle. Kevin said that stall was just a little shutter followed by a nose drop. I?m guessing that?s right since the pitch in his voice didn?t change during the event :)

If you want the straight poop, Mel, drop me an email at [email protected] and I will give you Kevin?s email address.

Tell Tim to keep at it, and expect a call from Kevin when the Cub is finished.

Tailwinds,

Wes
C-150 Flying since 1973
RV-6A Flying since 2003
Sonex Flying for two weeks.
 
Sonex like an RV

Having built and then flown a Sonex for two years, I can say they fly great. AS far as comparison with RV's, I only have about 5 minutes stick time in a 6A and I found them quite similar; light on the controls and quick response. The Sonex is the best bang for the buck, but won't do what current RV's do. The RV-12 may be much closer. By spring I should have my RV-6 done and by next year at this time I will be under way building another Sonex. Partly because I love building and partly because the Sonex is so inexpensive to build and fly. BTW, I had $18,000 in my Sonex and the -6 isn't done and nearing $40,000. You can bet the RV-12 will cost at least 25-30,000 to build.
Ron Voss
RV-6 almost ready for paint
 
Surface Warrior said:
Has anyone done any research on the Sonex? Thinking this might be a good alternative to the RV-12
Click to expand...
While I was seriously considering the Sonex, I visited their facility at KOSH. Nice operation, CNC parts, and outstanding "bang for the buck".

Unfortunatley, I had to rule out the Sonex after I sat in one. It just doesn't have nearly enough headroom for me.

Without knowing your situation (aka - if you're a short guy, then "go for the Sonex"), I'd encorage you to take a look at the Zenith 601XL. There's also the RANS S-19, however that is an unproven design as far as I know.

Good luck!

- PatrickW
 
I'm not sure if this is too dis-similar because it isn't metal but it is a low wing fast build jabu 3300 LSA compliant [or regular experimental if you'd rather] alternative:

Lightning Aircraft

LSA compliant and experimental version

Lightning forum:

http://forums.matronics.com/viewforum.php?f=64

website:

http://www.arionaircraft.com/


a short description and pilot?s impression:

http://forums.matronics.com/viewtopic.php?t=12480

It is most similar to the -9A in performance and is a modular composite design [a major modification of the Esqual [there is a recent thread describing the differences between the two in Matronics]]. If you go to their factory in Tn you can have something ready to paint in a week... After painting [they will job it out there or you can trailer it] they say you can spend another week at their shop and have it ready to fly. Their web site has all the details.

I'm not trying to cause a rukus... just give another alternative to the LSA mix

John
 
Thanks everyone for your thoughts on my original post about the Sonex as an alternative to the RV-12.

I am 5'8" and 165lbs. so I would probably fit easily in the Sonex. Wife is 5'4" and 125lbs. (but don't tell her I told you!) so we should both fit easily in the Sonex.

I ordered the brochure and DVDs from Sonex last week, and I am very impressed. Especially impressed by Tony Spicer's DVD showing the flight characteristics of the Sonex.

Having owned a M20C, I'm sold on low-wing aircraft for their great vis in the air and especially in the pattern.

The key for me is the low cost for an LSA compliant aerobatic speedster at $25-$35,000 depending upon which engine. I like the Aero Vee because it is a kit built engine, and would provide great education to build my own engine; however, at 80hp I'm leaning toward the Jabiru 3300 for the extra hp, and cruise speed at altitude.

Just exploring options before I commit to building. Wife thinks I should build an RV; but I'm leaning toward Sonex for the lower cost and LSA. Nevertheless, waiting until the RV-12 flys before ordering a kit.

I am considering attending the Sonex workshop to get a hands on introduction. I took the RV workshop here in Indianapolis last year, and learned my wife and I have the skills necessary to build our own airplane.

I also think I'd prefer pulled rivet construction over flush rivets from an ease of build perspective.

Thanks again for the thoughts you all shared with me.
 
Zenith Zodiac XL?

It is not a Sonix by why not take a look at the Zenith Zodiac XL?

It has more room than an RV-6,7,9 and can be built as an LSA. It is pulled rivet construction like the Sonix.
 
Something about that center "Y" yoke in all the Zenith planes just rubs me the wrong way... early on I was looking at the 801 for Baja travel, but 100 mph is just a bit too slow for my liking.

See Octobers issue of EAA's Sport Aviation for a great article on a customer built Waiex that cost $24k to build with tons of extras like a smoke system, glass instrumentation and custom paint and flame job.

I don't know - now it's got me thinking...
 
Baja_Traveler said:
Something about that center "Y" yoke in all the Zenith planes just rubs me the wrong way...
Click to expand...
Dual sticks are available for the 601XL. All in all, a pretty nice plane. Only real downside is getting in and out is a little tough due to the seat recline. Lots of operating experience with this airplane, and you can a matched hole kit. And, if you're really lazy, you can get a factory built bird ;)

Seriously, though, I'd like to see the differences between the factory built 601 and kit built 601s. Wonder what they're doing differently.
 
Sport Pilot Aerobatics

ddurakovich said:
Unfortueately, as I recall, the Sport Pilot certificate is not approved for aerobatics.

I can't find anything about acrobatics in the FAR 61.315, which would mean acrobatics are o.k.

Where did you read that Sport Pilots are not approved for aerobatics?

Chase
www.flybigbend.com
Click to expand...
 
From the IAC web site.

http://www.iac.org/programs/competition.html


What are the Requirements to Compete in a Sanctioned Aerobatic Contest?
You must be a member of the Experimental Aircraft Association (EAA) and the International Aerobatic Club (IAC), a division of the EAA. You must also possess a minimum of a Sport Pilot certificate if flying a qualifying Light-Sport Aircraft (LSA), or at least a Recreational Pilot certificate with rating appropriate for the class of aircraft to be flown (power or glider) if flying an aircraft other than a LSA. A pilot competing with a Sport Pilot certificate must also possess either a valid U.S. driver?s license which complies with the restrictions set forth in the applicable sections of the FAR?s, or a current medical certificate. All other certified pilots of powered aircraft must possess a current medical certificate. These licenses and certificates must be shown to contest officials on request.
 
N941WR said:
It is not a Sonix by why not take a look at the Zenith Zodiac XL?

It has more room than an RV-6,7,9 and can be built as an LSA. It is pulled rivet construction like the Sonix.
Click to expand...

I have not flown in one but I know a person that went to the factory in Mexico, MO to fly one to help him make up his mind. He came away liking the airplane roominess and feel of the interiro but disliking the heavy controls and roll rate. He owns a Titan Tornado with 1200 hours and likes to do loops and rolls which he felt the Zenith would not do. BTW, he flew to the Zenith factory in an RV6 from MN to do the check ride so he is well aware as to what light and responsive controls are all about.

One goofy thing about the Sonex is the factory's unwillingness to do demo rides. Not sure why they do that but that does not sit well with many folks.

J Borja
Elk Mound, WI
 
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My understanding is the "heavy" controls primarily reference the ailerons. They have two styles - a "hingeless" one in which the top skin of the wing and the aileron is all in one, and a second style which uses a piano style hinge. Supposedly all the quick-build use the piano style hinge.

http://www.zenithair.com/zodiac/xl/design-wings.html

I have read several places that the piano-hinge provides much better controls - and is quite pleasant to fly.
 
Phyrcooler said:
My understanding is the "heavy" controls primarily reference the ailerons. They have two styles - a "hingeless" one in which the top skin of the wing and the aileron is all in one, and a second style which uses a piano style hinge. Supposedly all the quick-build use the piano style hinge.

http://www.zenithair.com/zodiac/xl/design-wings.html

I have read several places that the piano-hinge provides much better controls - and is quite pleasant to fly.
Click to expand...
You can find details of the hingeless ailerons on the Zenith site. Chris Heintz seems to be comfortable with the hingeless design, but obviously, some perfer the hinge design.

I believe that the AMD built 601XLs use the piano hinge design.

Doug
 
Phyrcooler said:
My understanding is the "heavy" controls primarily reference the ailerons. They have two styles - a "hingeless" one in which the top skin of the wing and the aileron is all in one, and a second style which uses a piano style hinge. Supposedly all the quick-build use the piano style hinge. I have read several places that the piano-hinge provides much better controls - and is quite pleasant to fly.
Click to expand...

That style of aileron, where the hinge is at the front edge of the aileron does not lend itself to provide light controls forces. For example, the RV aileron is counterbalanced and has a hinge several inches aft of the front edge of the aileron. The RV has a shorter throw to overcome the aileron forces than the Zenith design (think fulcrum or momentum).

The aileron design in my airplane is similar to the Zenith design with the hinge at the leading edge. To achieve light controls we install aileron spades or as we call it power steering. I imagine the Zenith could use them too but being a low wing one must the windful of the weeds. I flew my airplane for 400 hours w/o spades and thought the controls were nice when compared to my Cessna and Piper days. When I installed the spades the airplane's ailerons can be maneuvered with two fingers and I can use my knees as a form of Auto pilot with gentle nudges on the stick.

The stabilators use an anti-servo tab that makes them light as long as the trim is set at the right spot. Hard to do a loop if the thing ain't right. The RV12 uses a stabilator and the tab seems to be a bit large but only flight testing will tell. Too much tab and the stab becomes too heavy. Not sure if the RV12 ailerons will use the same RV aileron design from the big guys.

J Borja
 
over 30 to choose from

The latest EAA sport aviation has the who's who list of LSA's ready to fly and kits. I did not know, there are over 30 models and types. I like the cub look a like.

It remains to be seen how many will be around in a few years.

I just have a problem with the 135 mph limit. HP limit, weight limit, I can see, but speed means you have to detune the airframe, make it less efficient.

Why have a slick airframe? Might as well have struts and stuff hanging out. That is why I like the STOL LSA's. You could under power it to keep the speed down, but climb will really be poor.

I think they would have been better to limit the HP not the speed, but that is my opinion.
 
I think the reasoning is that an inexperienced pilot is more likely to get himself in trouble with a fast airplane, as opposed to a powerful one. I agree with that.
 
Cessna made their first LSA flight yesterday. I wish Van's would have beat them to the punch. Looking forward to ANY news of progress.
 
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PatrickW said:
Hey - take a look at this: http://www.airfox.com.br/modules/news/

Scroll all the way down - it looks a lot like the RV-12 prototype that was at Oshkosh this year.

Looks like it's still under construction, but further along. Does anybody know Spanish who can tell us anything?

- Patrick
Click to expand...

It's portugese. The company took a Zenith Zodiac XL and made some modifications of their own (turtledeck, canopy, and wingltes), including a BRS system. The named it Zodiac XL 601 RB.

Jose B.
ELk Mound, WI
 
Doug says that Ken talked about the RV-12 at LOE. Did anyone on the forum hear his talk? I so, what did he say about the progress?

Thanks...
 
Performance claims

I would offer the cautionary note that not all kitplane manufacturers are realistic when it comes to performance claims.

My little Zenair as supposed to cruise at 140mph on only 80HP. The reality was 120mph flat out.

I was dissappointed on my very first flight....Don't let this happen to you...buy an RV...:)

Frank
 
frankh said:
I would offer the cautionary note that not all kitplane manufacturers are realistic when it comes to performance claims.

My little Zenair as supposed to cruise at 140mph on only 80HP. The reality was 120mph flat out.

I was dissappointed on my very first flight....Don't let this happen to you...buy an RV...:)

Frank
Click to expand...
Agreed - the Zenair and RANS claims seem a little high. Some estimates are low however - I'm still flying the CTSW this week and because of the LSA rule, the prop is set very aggressively, and we develop max 5100 RPM in flight. This is about 75Hp according to the Rotax graphs and 115 kt according to the GPS.

If I were building a non-LSA 601XL, I'd go for the Jabiru engine - you could use the extra power for speed.
 
the_other_dougreeves said:
Agreed - the Zenair and RANS claims seem a little high. Some estimates are low however - I'm still flying the CTSW this week and because of the LSA rule, the prop is set very aggressively, and we develop max 5100 RPM in flight. This is about 75Hp according to the Rotax graphs and 115 kt according to the GPS.

If I were building a non-LSA 601XL, I'd go for the Jabiru engine - you could use the extra power for speed.
Click to expand...

5100 RPM flat and level on a 912S makes me believe the engine is only developing about 4900 RPM on takeoff and climb unless a Warp Drive tapered prop is used. After much experimenting, my 912S is set for 5360 RPM straight and level and short only 140 RPM from the max continous of 5500. Thanks to the WARP drive prop I do not experience a significant lloos of RPM on take off and still expereince 1200 fpm solo at 5340 RPM.

I would not operate my engine if it only reached 5100 RPM at WOT. I find it hard to believe the CT takes off at all since 5100 RPM is only 2090 RPM on the prop. That is a testament on the CT designs ability to fly underpowered.

If it were me, I would have the tach checked against prop RPM because 5100 RPM is way too low. Withot looking at the EGTs, it's hard to say how that puppy is working. If the RPMs are accurate that helps explain why we saw a CT airplane at a recent flyin this summer in Minnesota eat up all the 1100 feet of the grass runway and barely clear the bean field. The good news is those that want to thinker with the prop ona CT can get a lot of juice from a single squeeze. I would hang a Warp drive and set it at 5500 RPM wot and call it a day.

J Borja
Elk Mound, WI
 
PepeBorja said:
5100 RPM flat and level on a 912S makes me believe the engine is only developing about 4900 RPM on takeoff and climb unless a Warp Drive tapered prop is used. After much experimenting, my 912S is set for 5360 RPM straight and level and short only 140 RPM from the max continous of 5500. Thanks to the WARP drive prop I do not experience a significant lloos of RPM on take off and still expereince 1200 fpm solo at 5340 RPM.

I would not operate my engine if it only reached 5100 RPM at WOT. I find it hard to believe the CT takes off at all since 5100 RPM is only 2090 RPM on the prop. That is a testament on the CT designs ability to fly underpowered.
Click to expand...
Yes, that's right, we see just shy of 5000 RPM on TO.

I'd really like to adjust the prop for the CT to reach 5400 at level flight and WOT. This would allow the Rotax to make (near) rated power on TO. The legality of this under LSA rules is iffy, unfortunately, as it would result in higher cruise.

The TO and climb performance is highly dependant on the flap setting. For shorter runways, use Flaps 15. Distances are pretty short and the climbout is good. During transition training, we did intersection takeoffs with about 2000ft of runway, pretty heavy (factory pilot wasn't exactly thin), DA around 2000'. We were doing T&Gs (more "slow and go"s) in this distance quite happily.

Using Flaps 0 results in a longer TO roll, but the airplane climbs out faster (IAS) and lower deck angles. The CT's wing is highly affected by the flaps, and going from Flaps 15 to 0 results in a very noticable sink and jump in airspeed; you also see it going from Flaps 0 to -6.

Strangely, using Flaps 15, I haven't noticed a big difference in climb performance between solo and dual. Maybe the drag is dominating performance?
 
the_other_dougreeves said:
Yes, that's right, we see just shy of 5000 RPM on TO.

I'd really like to adjust the prop for the CT to reach 5400 at level flight and WOT. This would allow the Rotax to make (near) rated power on TO. The legality of this under LSA rules is iffy, unfortunately, as it would result in higher cruise.
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Has the tach been checked? 5000 RPM sounds really low. What is the Manifold pressure on takeoff? Maybe the engine/prop is ok but the tach is reading goofy? I have seen that before when I synch carbs for 912 engines.

I know what I would be doing to that airplane if it were in my tuning hands. If it does that sweet a job at 5100 I can't imagine dialing up 5500 RPM and 25 inches of MP for some fast cruise.

I have seen two CT airplanes and they look fine. The interiors are very nice and the visibility appears to be great with the high wing and no struts.

Jose Borja
Elk Mound, WI
 
PepeBorja said:
Has the tach been checked? 5000 RPM sounds really low. What is the Manifold pressure on takeoff? Maybe the engine/prop is ok but the tach is reading goofy? I have seen that before when I synch carbs for 912 engines.
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I think the engine is Ok. The problem is that the prop is set by the factory so that the CT does not exceed 120kt to qualify as an LSA. It's a ground-adjust prop.

PepeBorja said:
I know what I would be doing to that airplane if it were in my tuning hands. If it does that sweet a job at 5100 I can't imagine dialing up 5500 RPM and 25 inches of MP for some fast cruise.

I have seen two CT airplanes and they look fine. The interiors are very nice and the visibility appears to be great with the high wing and no struts.

Jose Borja
Elk Mound, WI
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Visibility is indeed very good. The interior could use some more storage cubbyholes, etc. Lots of baggage room and weight allowance (110 lb). Landings are a little tricky due to the nose-down pitch on final with flaps 30 or 40 and the spring gear's tendancy to bounce, but they improve with practice.

I would be most interested in flying the CT with the prop set to allow 5500 RPM.
 
the_other_dougreeves said:
I would be most interested in flying the CT with the prop set to allow 5500 RPM.
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Get the tools out and adjust the prop to see what numbers you get. Of course, that depends on your tolerance for Fed paranoia in that they will somehow know the propeller was adjusted to make the engine work like the good Lord intended it to work. I did have my prop adjusted for cruise at 5550 RPM and takeoffs were sweet but my cruise hurt a little. I finally settled on the 5360 max RPM as a good compromise.

I have been in this hobby long enough the Feds don't bother no one unless they end up soing something radically stupid. By then the prop can be set back or it wil be in pieces from the impact , so what differenece does it make anyhow.

It's like the militaty deal, "Don't ask, Don't tell". They don't want to know and you don'e want to tell.

After flying the high wing CT I am not sure you would like to have 120 sq ft of aluminum blocking your downward view, but that's just me. Them CT's are made for rough field too, right? The one I saw was at a U/L gathering flying off an 1100 foot wet grass runway.

Nice plane allright.

J Borja
 
PepeBorja said:
Get the tools out and adjust the prop to see what numbers you get. Of course, that depends on your tolerance for Fed paranoia ....
It's like the militaty deal, "Don't ask, Don't tell". They don't want to know and you don'e want to tell.
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Well, if it were my airplane, I might be spured into action. However, this one is on loan to me, so .....

PepeBorja said:
After flying the high wing CT I am not sure you would like to have 120 sq ft of aluminum blocking your downward view, but that's just me. Them CT's are made for rough field too, right? The one I saw was at a U/L gathering flying off an 1100 foot wet grass runway.

Nice plane allright.

J Borja
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Rough fields and the CT are a good question. Believe it or not, the stock tires are 400x6 mains and 400x4 nose. The "Tundra" tire option is 600x6 mains and 500x4 nose. Those seem small, but remember that MGTW is 1,320 lb. The "tundra" option also includes a reinforced nose gear and motor mount as well as enlarged wheel pants (that look HUGE).

The landing gear tube (single piece tube bolted to the fuselage) was strengthened for 2006. There were some failures of the gear tube prior to that with some hard landings.

You have plenty of authority to keep the nose light with the enlarged-for-2006 all-flying horiz stabilizer / elevator, but I wouldn't want to fly off anything but a decently maintained grass field with the stock setup. I would be most worried about the nose gear with the stock mount.
 
What's a "CT"?

I'm also eagerly awaiting any RV-12 news.

The 3-view drawings and construction photos of the Rans S-19 look pretty impressive, but they have nothing posted about a timeline - when the prototype is expected to fly, when they'll start shipping partial kits, etc. The wing loading photos are almost 2 years old.
 
KThorp said:
What's a "CT"?
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The CTSW is a LSA built Flight Design GMBH - actual construction has been moved from Germany to Ukrane. CT = composite two-seat, SW = short wing. Kind of looks like a flying jellybean. This shot shows how compact the Rotax is.

Jellybean_ADS-hangar_web.jpg

KThorp said:
I'm also eagerly awaiting any RV-12 news.

The 3-view drawings and construction photos of the Rans S-19 look pretty impressive, but they have nothing posted about a timeline - when the prototype is expected to fly, when they'll start shipping partial kits, etc. The wing loading photos are almost 2 years old.
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I suspect that the RV-12 is getting more attention than the S-19. Van's has more resources than RANS, and Randy and Co. has been spending a lot of time getting the S-7 (modern-day Cub with a Rotax) LSA production line going.
 
That CT looks very interesting, but as far as I can tell there is no kit available.

Do you know of any high-wing kit planes that have similar performance? The Zenith CH-701 has impressive short field capabilities but it's cabin is a bit tight for large pilots and isn't very fast (80-85 mph cruise).
 
KThorp said:
That CT looks very interesting, but as far as I can tell there is no kit available.

Do you know of any high-wing kit planes that have similar performance? The Zenith CH-701 has impressive short field capabilities but it's cabin is a bit tight for large pilots and isn't very fast (80-85 mph cruise).
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RANS has 2 - the S7S and S6S. Both cruise around 100 on a 100hp Rotax. They come in standard build, quick build and a version of the S7S comes ready-to-fly. I have flown an S6 and liked it. After my -8 is flying, I may consider one for 'low and slow' flying.
 
gpiney said:
RANS has 2 - the S7S and S6S. Both cruise around 100 on a 100hp Rotax. They come in standard build, quick build and a version of the S7S comes ready-to-fly. I have flown an S6 and liked it. After my -8 is flying, I may consider one for 'low and slow' flying.
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S6 is side-by-side, S7 is tandem. Both are fabric covered and 912S powered, although Jabiru has a 3300 FWF kit available. The S6 has a new "sport wing" that gives higher cruise speed (100kt) with no loss of climb or stall speed - basically, it improves the tips and smoothness of the fabric covering. It will be ported to the S7 sometime soon - might be worth waiting for.

S7 visibility and access are great. A very nice cub-like design. I have some detailed photos at home - I'll post them tonight.
 
The white S-7 is the first S-LSA certified from Rans. The next in line is a S-6ES which I helped build. The S-7 on floats was just purchased by another local fellow. And finally the Yellow S-7 is about 3 yrs old built by a friend of mine. The are great little "low&slow" flyers. 100mph on <5gph.
4inarow.jpg



The S6 has a new "sport wing" that gives higher cruise speed (100kt) with no loss of climb or stall speed - basically, it improves the tips and smoothness of the fabric covering. It will be ported to the S7 sometime soon
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The "sport wing is much nicer than the older style wing, easier to build also. BUT don't look for it anytime soon on the S-7, this is due to the certification process for the S-LSA.
 
That is a line up of good-looking planes Brian.

Are there any aluminum or composite high-wing kits >100mph?

It looks like a lot of companies are offering low-wing designs but the only semi-speedy high wing a/c I can find are factory-built LSAs. I'm no marketing whiz but it seems like there's a void there.
 
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Take a look

KThorp said:
That is a line up of good-looking planes Brian.

Are there any aluminum or composite high-wing kits >100mph?

It looks like a lot of companies are offering low-wing designs but the only semi-speedy high wing a/c I can find are factory-built LSAs. I'm no marketing whiz but it seems like there's a void there.
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http://www.titanaircraft.com/index.php

I have always admired this one.

Mike
 
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