Sonex Onex

steingar said:
What is really valuable (and nearly impossible to ascertain) is the accident/time flown rate. That relates both to fleet size (which can be gleamed from FAA records) and time flown, which can be gleamed from your local neighborhood gypsy, perhaps. You can get a bit of a clue from fleet size. I imagine time in flight is less for the Sonexes and their brethren, since they aren't very big, don't have a lot of creature comforts, and I imagine aren't mostly used for travel.
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Just by chance :) I also analyze the FAA registry to try to determine the number of registered examples of each homebuilt type. Put them together with the accident data, and....
hb_fleet.jpg

"Fleet Accident Rate" is the average number of aircraft of that type that suffers crashes in a year.

The overall homebuilt fleet accident rate is about 0.7% per year. The overall GA rate is about 0.6%

Hours are a major factor here, but reliable estimates aren't really out there. The FAA publishes some broad estimates, not by aircraft type, and the majority of the GA hours they list are for commercial or business purposes, which doesn't really apply to homebuilts.

THAT said, I do run my own, rough, estimate of annual hours by homebuilt type. This IS rough and ugly, based on the utilization rates of the aircraft in the accident database. I hesitate to post any real details. But the main gist is that the lil' sporty guys (like the Fly Baby, Piet, Sonex, etc.) see 40-50 hours per year, while the fancier machines (RVs, Lancairs, etc.) see 60-80.

Ron Wanttaja
 
Kinda what you'd expect, in that the faster machines used more for travel than just flying around suffer more accidents. More complex systems (to manage, misbuild or break), more hours flown, and flown though more challenging conditions.
 
So bottom line, if you know how to assemble and care for the engine then it's probably not any more or less unsafe than any other engine.

The fact that you buy the engine as a kit means you get the chance to induce error.
 
As a sonex builder/owner I'll chime in here. The airframe of the Sonex/Waiex/Onex is extremely robust, simple to build, and fairly inexpensive. Except for one accident on a Waiex where the tail failed (read the report and it becomes very obvious that the builder had no idea what they were doing) there have been no other structural issues with the airframe. They are very much overbuilt. Take a look at the wing spars and you will see what I am referring to.

Here is the rub though. The aerovee engine has a horrible safety record. There have been way too many engine failures on takeoff with many of those resulting in fatalities or severe injuries. It isn't just a problem of people not building or maintaining the aerovee correctly. If that were the case then there wouldn't have been two factory with aerovee's who failed and crashed on takeoff. One ended up killing the owner's son and a factory employee and the other severely injured a company flight instructor and a customer doing transition training in the factory Waiex.

My plane has not been flown in a year and a half because I just don't trust the aerovee engine. If the factory with all their knowledge can't get it right how are other builders supposed to. I am currently trying to decide if I want to sell the whole plane, change the powerplant to something else, or modify the aerovee to remove what I think are its weak spots.

Keith
Sonex #554
 
kmacht said:
As a sonex builder/owner I'll chime in here. The airframe of the Sonex/Waiex/Onex is extremely robust, simple to build, and fairly inexpensive. Except for one accident on a Waiex where the tail failed (read the report and it becomes very obvious that the builder had no idea what they were doing) there have been no other structural issues with the airframe. They are very much overbuilt. Take a look at the wing spars and you will see what I am referring to.

Here is the rub though. The aerovee engine has a horrible safety record. There have been way too many engine failures on takeoff with many of those resulting in fatalities or severe injuries. It isn't just a problem of people not building or maintaining the aerovee correctly. If that were the case then there wouldn't have been two factory with aerovee's who failed and crashed on takeoff. One ended up killing the owner's son and a factory employee and the other severely injured a company flight instructor and a customer doing transition training in the factory Waiex.

My plane has not been flown in a year and a half because I just don't trust the aerovee engine. If the factory with all their knowledge can't get it right how are other builders supposed to. I am currently trying to decide if I want to sell the whole plane, change the powerplant to something else, or modify the aerovee to remove what I think are its weak spots.

Keith
Sonex #554
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Your candor is greatly appreciated. Thanks.
 
kmacht said:
Here is the rub though. The aerovee engine has a horrible safety record. There have been way too many engine failures on takeoff with many of those resulting in fatalities or severe injuries. It isn't just a problem of people not building or maintaining the aerovee correctly. If that were the case then there wouldn't have been two factory with aerovee's who failed and crashed on takeoff. One ended up killing the owner's son and a factory employee and the other severely injured a company flight instructor and a customer doing transition training in the factory Waiex.

My plane has not been flown in a year and a half because I just don't trust the aerovee engine. If the factory with all their knowledge can't get it right how are other builders supposed to. I am currently trying to decide if I want to sell the whole plane, change the powerplant to something else, or modify the aerovee to remove what I think are its weak spots.

Keith
Sonex #554
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The NTSB said the engine had no anomalies one the one that killed the owner's son. They think it was the turbo waste gate. They also said he used a small portion of the runway for an intersection takeoff and would have had enough room to land if he didn't.

Sorry to hear you don't trust the engine. That has to be frustrating after building a plane. A friend of mine had a Corvair engine in his and loved it.
 
kmacht said:
As a sonex builder/owner I'll chime in here. The airframe of the Sonex/Waiex/Onex is extremely robust, simple to build, and fairly inexpensive. Except for one accident on a Waiex where the tail failed (read the report and it becomes very obvious that the builder had no idea what they were doing) there have been no other structural issues with the airframe. They are very much overbuilt. Take a look at the wing spars and you will see what I am referring to.

Here is the rub though. The aerovee engine has a horrible safety record. There have been way too many engine failures on takeoff with many of those resulting in fatalities or severe injuries. It isn't just a problem of people not building or maintaining the aerovee correctly. If that were the case then there wouldn't have been two factory with aerovee's who failed and crashed on takeoff. One ended up killing the owner's son and a factory employee and the other severely injured a company flight instructor and a customer doing transition training in the factory Waiex.

My plane has not been flown in a year and a half because I just don't trust the aerovee engine. If the factory with all their knowledge can't get it right how are other builders supposed to. I am currently trying to decide if I want to sell the whole plane, change the powerplant to something else, or modify the aerovee to remove what I think are its weak spots.

Keith
Sonex #554
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Wanna trade for a Luscombe?
 
Lowflynjack said:
The NTSB said the engine had no anomalies one the one that killed the owner's son. They think it was the turbo waste gate. They also said he used a small portion of the runway for an intersection takeoff and would have had enough room to land if he didn't.

Sorry to hear you don't trust the engine. That has to be frustrating after building a plane. A friend of mine had a Corvair engine in his and loved it.
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It's true that the NTSB found nothing internally wrong with the engine or the waste gate on the first factory aircraft crash. They spent considerable time looking at the turbo setup as this was supposed to be the factory demonstrator for the turbo. That doesn't negate the fact that there was a puff of smoke coming from the exhaust during takeoff right before the engine stopped and it crashed. The report confirmed that there was no rotational damage to the engine which was consistent with a loss of power before the accident. If this were a one time incident I would have put it off as a fluke but the fact that it happened to a second factory aircraft (non-turbo aerovee) a year later as well as also to a number of other people flying behind an aerovees says indicates that there is some sort of systemic issue. Personally I think it has to do with the aerocarb and the fuel system but I don't have data to back that up. Regardless, it is enough to keep me from flying behind one.

As far as the intersection takeoff, it obviously wasn't a good idea but the runway he had available was longer than some others regularly fly out of. He had a little more than 2500' available for takeoff. The sonex usually uses between 600 and 800 feet before it lifts off. The whole accident was a series of unfortunate events. Had the engine not quit, had he used the full runway, had there not been oshkosh trucks parked just off the end of the runway, had he not stalled it after the engine quit, etc all contributed to the outcome.

The corvair is one option I am seriously looking at. I bought the WW conversion manual and currently have a torn down serviceable core sitting in pieces on a bench in my shop. What is stopping me is the cost. It is going to be 10k or so to build the motor up, install a new mount and build a new cowling. Not sure if it is worth putting that much more money into an airplane that sells for 25k on a good day. For those considering a onex, there might be an option for the rotax 912. I know that the factory was selling rotax mounts for the sonex/waiex models. Not sure on the onex. A few have put in the 6 cylinder jabiru's and a few others have installed other VW competitor engines. I know at least one person has put an o-200 in a sonex.

Keith
 
Is there an alternate VW based engine nit eold as a kit? As in, mount, plumb, fly?
 
Lowflynjack said:
However, running at 3200 RPM for that long, I hope to have an engine I can believe in.
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HKS like in my Carlson only lasts 1,000 TBO at 5,800 rpm. That's it. Although, the Rotax 912ULS last 2,000 hours easily, if flown regularly. They spin at about 5,000 rpm and factory representatives say that it's actually good for the engines. They caution against running a 912 family below 4,800.

A 80hp Rotax would be great on Onex, I think. It's not much heavier than AeroVee (same weight when dry, but unfortunately needs water). The only problem is cost. It's about 2 times more expensive.

BTW, after years and years of resistance, Sonex introduced factory parts for Rotax 912
https://www.sonexaircraft.com/pr_071417-2/
 
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Sundancer said:
Is there an alternate VW based engine nit eold as a kit? As in, mount, plumb, fly?
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Revmasters are sold complete and test run as well.

Also, UL Power offers an engine mount for most Sonex kits. It will add about $15,000 to the final cost to use UL power rather that the Aerovee.

I would personally not fly behind an engine that wasn't built by someone who does that on a regular basis or hadn't been run in on a test cell or on a dynamometer.
 
FormerHangie said:
Also, UL Power offers an engine mount for most Sonex kits. It will add about $15,000 to the final cost to use UL power rather that the Aerovee.
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UL always was expensive. Roughly, the 80 hp Rotax 912 is 2x Aerovee, and the (smallest) UL is 3x. But you get a FADEC, direct drive, and way more power: 97 hp rated (may need an unusual prop to convert all that power into thrust, given Onex's prop diameter).
 
I can’t vouch for the Hummel product as I haven’t flown behind it but will say that the guys running the business are top notch. I got stuck for two days in Bryan Ohio due to weather while trying to fly the sonex to Oshkosh. I didn’t know it at the time but Hummel was based there. They offered me free use of their hanger for the plane, a car to get around, hotel and food recommendations, as well as some great local weather knowledge. They made a frustrating and stressful stop somewhat enjoyable.

One other engine to look at is the Viking. It is a Honda Fit engine with some modifications. A few are flying in sonex airframes with good results. The only down side is the reputation of the company founder. He didn’t have a very good track record with his Subaru conversion and left a bunch of people out of money and with bad engines. Haven’t heard the same about the Viking but it’s hard to regain trust in the small aviation community.

Keith
 
kmacht said:
I can’t vouch for the Hummel product as I haven’t flown behind it but will say that the guys running the business are top notch. I got stuck for two days in Bryan Ohio due to weather while trying to fly the sonex to Oshkosh. I didn’t know it at the time but Hummel was based there. They offered me free use of their hanger for the plane, a car to get around, hotel and food recommendations, as well as some great local weather knowledge. They made a frustrating and stressful stop somewhat enjoyable.

Keith
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The Hummel VW engine is actually from Scott Casler in Arizona, near Phoenix. Different company altogether AFAIK. No idea how he came by the Hummelbird connection.

Cheers
 
I think you guys have convinced me to keep looking for a fun airplane! I'm not interested in building a Onex, just buying one, but all of them on the market have the Aerovee engine. My two biggest reasons for liking this plane was the size and that it is aerobatic. On paper, this is a cool little plane. Aerobatic, folding wings, up to 150mph cruise (depending on who you ask) at only 4 gph. If I felt I wouldn't get stuck with it or that I wouldn't have issues with the engine, I would like to fly one for awhile. Oh well, off to other dreams.

Thanks for all of the info!
 
Something to think about. The engine failures linked here were all from the builders building engines themselves. You might ask the sellers who built the engine. Perhaps they hired it out to someone experienced in engine construction. Or perhaps they were sufficient gear heads to be able to do it competently. There are lots and lots of these things flying around without incident, and I doubt there's anything inherently wrong with the engine. It's an engine from the VW Bug for Odin's sake!
 
steingar said:
Something to think about. The engine failures linked here were all from the builders building engines themselves. You might ask the sellers who built the engine. Perhaps they hired it out to someone experienced in engine construction. Or perhaps they were sufficient gear heads to be able to do it competently. There are lots and lots of these things flying around without incident, and I doubt there's anything inherently wrong with the engine. It's an engine from the VW Bug for Odin's sake!
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The problem is that two factory maintained airplanes with factory built aerovee engines operated by factory built pilots were lost in crashes due to what appears to be loss of power events.

If they can’t get it right - what makes you think anyone would have?

I considered one a few years back. Ultimately I walked away from the idea for these reasons:
- The factory designed friction fit slip on prop hub design is flawed imo. Nothing wrong with it in principal - it’s just that the OEM vw crank is not set up for this. The friction fit prop hub isn’t going to slip off. But the crank may crack. No thanks.
- they shipped many cases with the oil passage completely blocked to the No. 4 bearing. Something like 1 in 8 at one point. Wouldn’t matter so much in a vw car where the bearing is taking basically no load. Matters a lot when you’re putting a prop on it. Damn bearing doesn’t get enough oil if everything is ideal for that much load (it wasn’t designed to).
- the Aerovee carb sounded like junk to me. I read of too many problems. Too sensitive to flow bubbles. Leaks fuel. Vapor lock problems. Won’t tolerate a fuel pump. Too ****ing sensitive.
- the oem quality control on the factory sold engine components was not acceptable imo. Just randomly shipping out parts that should in theory make an engine if you assemble it, though likely a poorly balanced engine given the loose vw factory tolerances combined with no real effort to reduce that margin.
- I was convinced the engine needed more displacement for two people.

At the end of the day - I don’t think the vw engine makes a good aircraft engine - for countless reasons. It’s tempting to do to save a buck but it’s a serious compromise with some engineering flaws that just aren’t acceptable in a production product.
 
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jesse said:
The problem is that two factory maintained airplanes with factory built aerovee engines operated by factory built pilots were lost in crashes due to what appears to be loss of power events. If they can’t get it right - what makes you think anyone would have?
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I still say that on at least one of these, calling it an engine failure isn't fair. The NTSB agrees there was a loss of power, but found nothing wrong with the engine. We tend to hear what we want to hear and once the rumor is out, we stick with what we believe. The engine was found to have no issues, it seems they would suspect the turbocharger, but couldn't even prove that. Still there's enough concern about the engine to make me skeptical of flying behind one at least for now.

CEN15FA249

During examination of the wreckage, no evidence of airframe malfunction or failure was detected. The propeller displayed no evidence of rotational damage, consistent with a loss of engine power before impact. The engine's turbocharger would not rotate, and the turbocharger compressor housing displayed impact marks made by the compressor wheel, indicating that there was little relative motion between the blades and the housing at the time of the impact. The turbocharger's wastegate system was tested on an exemplar engine, and no anomalies were noted. It could not be determined whether the turbocharger would not rotate due to impact damage or whether it seized in flight resulting in a partial loss of engine power. Engine test runs with a turbocharger in a seized condition could not be conducted.

The mixture control lever was found near the idle-cutoff position with a corresponding witness/impact mark around the circumference of the control stem, indicating that the lever was in the cutoff position at the time of impact. It could not be determined at what point during the flight the lever was moved to the cutoff position. Attempts to produce white smoke from the engine by leaning the mixture to the cutoff position and by inducing a loss of engine power due to water contamination were unsuccessful. The exemplar engine's failure to produce white smoke when the mixture was leaned suggests that the loss of engine power was not the result of the pilot moving the mixture control lever to the cutoff position during takeoff. It is possible that the pilot moved the lever to the cutoff position after the airplane departed from controlled flight. The reason for the loss of engine power could not be determined.

The circumstances of the accident are consistent with the pilot failing to maintain sufficient airspeed following a loss of engine power during takeoff, resulting in the airplane's wing exceeding its critical angle-of-attack and a subsequent aerodynamic stall. Instead of using the full runway length of 6,179 ft, the pilot elected an intersection takeoff with about 2,570 ft of available runway. Calculations showed that, had the pilot used the entire runway for takeoff, sufficient runway for a landing following the loss of engine power would likely have been available.
 
steingar said:
Something to think about. The engine failures linked here were all from the builders building engines themselves. You might ask the sellers who built the engine. Perhaps they hired it out to someone experienced in engine construction. Or perhaps they were sufficient gear heads to be able to do it competently. There are lots and lots of these things flying around without incident, and I doubt there's anything inherently wrong with the engine. It's an engine from the VW Bug for Odin's sake!
Click to expand...

There are not lots of VW powered airplanes flying around. Quite a few have been built, but you do not see them at pancake breakfasts or Oshkosh. There is a reason. Fundamentally, the engines do not perform as advertised and the maintenance to keep 'em flying is excessive. They become hangar queens, then go to the great fly-market in the sky or show up on Craigslist.

Capt. Geoffrey Thorpe said:
Many have a single ignition system so a failure would seem to more likely to result in lost power compared to an engine with two mags.
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We had two KR2's go down locally (one fatal) due to ignition failure.

Personally, I am unimpressed with the VW engine as applied in the Sonex, Onex, KR-2, etc. If you were willing to run it at 2700 rpm/35 HP, it would be a fine engine for a low and slow putt-putt airplane with a low stall speed. But, put a tiny prop on it, spin it 3,000+ RPM trying to go fast in an airplane with a higher stall speed, and then subject the crank to the forces involved in aerobatics or similar flying ? No, no, no, and no.

As an EAA tech counselor, I've inspected three aircraft with alternative engines. None of the pilots have been hurt (yet), but none of the aircraft are flying today with their original engines, either. Too many problems, too poor performance, too little reliability, etc. The above average Joe simply doesn't have a good record of success with alternative engines.
 
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jesse said:
The problem is that two factory maintained airplanes with factory built aerovee engines operated by factory built pilots were lost in crashes due to what appears to be loss of power events.

If they can’t get it right - what makes you think anyone would have?

I considered one a few years back. Ultimately I walked away from the idea for these reasons:
- The factory designed friction fit slip on prop hub design is flawed imo. Nothing wrong with it in principal - it’s just that the OEM vw crank is not set up for this. The friction fit prop hub isn’t going to slip off. But the crank may crack. No thanks.
- they shipped many cases with the oil passage completely blocked to the No. 4 bearing. Something like 1 in 8 at one point. Wouldn’t matter so much in a vw car where the bearing is taking basically no load. Matters a lot when you’re putting a prop on it. Damn bearing doesn’t get enough oil if everything is ideal for that much load (it wasn’t designed to).
- the Aerovee carb sounded like junk to me. I read of too many problems. Too sensitive to flow bubbles. Leaks fuel. Vapor lock problems. Won’t tolerate a fuel pump. Too ****ing sensitive.
- the oem quality control on the factory sold engine components was not acceptable imo. Just randomly shipping out parts that should in theory make an engine if you assemble it, though likely a poorly balanced engine given the loose vw factory tolerances combined with no real effort to reduce that margin.
- I was convinced the engine needed more displacement for two people.

At the end of the day - I don’t think the vw engine makes a good aircraft engine - for countless reasons. It’s tempting to do to save a buck but it’s a serious compromise with some engineering flaws that just aren’t acceptable in a production product.
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I had been doing some armchair research on VW powered airplanes, and came to the same conclusion. I really object to the idea of sending an inexperienced builder a box of parts and expecting him to successfully assemble a reliable aero engine. Maybe the factory built ones such as Revmaster and Limbach are fine, but I sure wouldn't fly behind one of the kits. I'm just about astounded that Aerovee is selling a turbo kit for an engine that is known to have thermal limitations.

If I were looking for an 80 HP engine for airplane or trike, I'd almost certainly go with Rotax.
 
BTW, if heat is a concern, there are high performance racing heads you can get for VWs, even some single cylinder heads so you can cool them individually. The engine runs normally in a car for hours on end at high RPMs on highways and pretty much as long as they have oil they don't have catastrophic problems. Personally, the VW engine doesn't fit me well. I want my airplane to go fast, so 80 or even 130 HP doesn't really work for me. I'm closer to the 180+ range, but maybe an o320 on the right (RV) plane...
 
I really wanted this to be the plane/toy for me. I have a 170 I can fly, and hopefully a Monocoupe soon! I just want a toy that I can go up for a quick flight and not worry about the cost. Even people who support the engine would have limited data to pull from it seems. Nobody has many hours one them and a couple of these have multiple owners in their short flying life.

Of the ones listed right now:
25 hours TT engine and airframe.
100 hours TT engine and airframe.
137 hours TT engine and airframe. At least two owners.
315 hours TT engined and airframe. This is the only one with around 100 hours per year on it.

Now I'm looking at something simple, like a Baby Ace!
 
Lowflynjack said:
Nobody has many hours one them and a couple of these have multiple owners in their short flying life.
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Low hours is typical for small, slow experimentals. I only has put something like 120 hours on the Carlson since 2013. It has 272 on Hobbs right now. Ron W. corraborrated this observation in the distant past. I suspect that it happens because hours are mostly gained in cross-countries, which these airplanes fly only rarely. Imagine that someone flies that Onex for an hour every Sunday afternoon, for months, without fail. That's a lot dedication to the hobby of flying, but only amounts to 50 hours a year. It's frankly amazing that someone's putting 100/y on one of those that you found.

I'm not surprised about owners either. The Carlson had 4 owners and is currently up for sale. The hangar rent is expensive and I cannot afford keeping this many airplanes. Unlike some rich pilots :)

Monocoupe sounds sick though. The only thing that's stopping me from wishing I had one is the realization that I'd never find time to fly it.
 
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I came here because I've fantasized about a Onex since they were announced. Not sure I have anything to add other than Ron Wattanja is the GOAT when it comes to providing perspective on this stuff. Maybe I should just build a Fly Baby instead and basically have a way slower, open cockpit, Onex.
 
dembro said:
I came here because I've fantasized about a Onex since they were announced. Not sure I have anything to add other than Ron Wattanja is the GOAT when it comes to providing perspective on this stuff. Maybe I should just build a Fly Baby instead and basically have a way slower, open cockpit, Onex.
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Come to the dark side. We have cookies.

Also, it doesn't necessarily have to the open cockpit. A number of Fly Babies have had canopies, and one of the Fly Baby crew even wrote up instructions.
mason3.jpg

Also, in honor of Pete Bowers' 100th birthday last month ("PB100"), the Fly Baby community is developing construction guides to go with the "How to Build a Fly Baby" articles that were published in EAA Sport Aviation 55 years ago. EAA members can download all 14 articles for free, and use the PB100 site for updates and more in-depth information.

http://www.bowersflybaby.com/PB100/index.html
pb100%20head.jpg

Ron Wanttaja
 
If you're going to build a sonex

subsonex.jpg


Otherwise like others have said, why not just a RV or a glasair or something.
 
kmacht said:
As a sonex builder/owner I'll chime in here. The airframe of the Sonex/Waiex/Onex is extremely robust, simple to build, and fairly inexpensive. Except for one accident on a Waiex where the tail failed (read the report and it becomes very obvious that the builder had no idea what they were doing) there have been no other structural issues with the airframe. They are very much overbuilt. Take a look at the wing spars and you will see what I am referring to.

Here is the rub though. The aerovee engine has a horrible safety record. There have been way too many engine failures on takeoff with many of those resulting in fatalities or severe injuries. It isn't just a problem of people not building or maintaining the aerovee correctly. If that were the case then there wouldn't have been two factory with aerovee's who failed and crashed on takeoff. One ended up killing the owner's son and a factory employee and the other severely injured a company flight instructor and a customer doing transition training in the factory Waiex.

My plane has not been flown in a year and a half because I just don't trust the aerovee engine. If the factory with all their knowledge can't get it right how are other builders supposed to. I am currently trying to decide if I want to sell the whole plane, change the powerplant to something else, or modify the aerovee to remove what I think are its weak spots.

Keith
Sonex #554
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I was thinking, man, best bet is to find another engine, going to have a hard time finding a sucker to pawn that thing off on.

Then

N659HB said:
Wanna trade for a Luscombe?
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Never mind!
 
dembro said:
I came here because I've fantasized about a Onex since they were announced. Not sure I have anything to add other than Ron Wattanja is the GOAT when it comes to providing perspective on this stuff. Maybe I should just build a Fly Baby instead and basically have a way slower, open cockpit, Onex.
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It sounds like the Ones is a decent airframe, it just needs a better engine. As long as you are building, you can install what you want.
 
James331 said:
I was thinking, man, best bet is to find another engine, going to have a hard time finding a sucker to pawn that thing off on.

Then



Never mind!
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I was seriously considering a Sonex (and Kitfox) before I bought the Luscombe. But I'd want a Jabiru 3300 in the Sonex. I'm tired of underpowered flight! ;)
 
wanttaja said:
Come to the dark side. We have cookies.
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I'll shoot you a message - I have questions about the FlyBaby - it just keeps popping up in my brain...

James331 said:
If you're going to build a sonex

subsonex.jpg
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Dude. Yes. I'm seriously thinking about trying to do the training/checkride in that thing just so I can have the experience (probably could never afford that plane though).

FormerHangie said:
It sounds like the Ones is a decent airframe, it just needs a better engine. As long as you are building, you can install what you want.
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Yeah - I was thinking about that, but.... does anything other than the Aerovee really fit on it? I think someone here mentioned a Jabiru, that's a TON of power for a tiny plane.
 
In all honesty an old C85 will not be much more expensive to build than a reliable VW engine. It will likely be cheaper to maintain in the long run especially in an experimental airplane.
 
I would do a C85 w/ 0200 crank, electronic ignition with auto spark plugs, airflow performance fuel injection, run the rpm a little higher, and a tuned exhaust. With some parts scrounging you could have over 100 hp for the same or less than a VW engine.
 
Grum.Man said:
I would do a C85 w/ 0200 crank, electronic ignition with auto spark plugs, airflow performance fuel injection, run the rpm a little higher, and a tuned exhaust. With some parts scrounging you could have over 100 hp for the same or less than a VW engine.
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I wonder how the weight compares?
 
I remember seeing a few Hummel birds with semi modified Polaris engines, wonder how those work in that role.

Personally I'd stick with a proven aircraft engine.

Though I always wished someone would make a good kit to use Harley jugs for a small radial, I'm sure there a million reasons that wouldn't work, but still lol
 
dembro said:
I wonder how the weight compares?
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It would certainly be heavier, I mean compare a C85 crank and case to a VW one. It would more than make up for it in power and tq though. The problem is nobody designs airplanes around those engines anymore. They are all either Rotax or VW/Corvair with the exception of the bearhawk lsa.
 
James331 said:
Though I always wished someone would make a good kit to use Harley jugs for a small radial, I'm sure there a million reasons that wouldn't work, but still lol
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At least it'd sound cool!
 
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