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Quick Build or Legacy for RV-10?

ledude

I'm New Here
Hi all.

I've been doing my research for my plan of attack with the RV-10. I've been watching the youtube channel that Jason Ellis made with his adventure to build the RV-10. A bit on the scary side with the amount of work that needs to be done. Not from the complexity perspective but the time consuming part that kind of make me wonder whether i should go with the QB route.

My concern (has not been confirmed yet) is that the QB was built without priming against corrosion/rust on the inside part. I thought it's a best practice to rust proof the inside part of the plane in order to avoid future headache with corrosion and rust. Can someone who has bought the QB RV-10 confirmed whether the QB kits come pre-primed with all the good stuff? Cuz if not, that'll be a major strike against QB for me. I just want to make sure that it's being built the right way.

Also has anyone ever look at the aeromomentum engine? They don't have the kit for RV-10 yet but I've been emailing back and forth with Mark Ketteing(I think he's the owner) and he said he'll build the firewall kit for me if I ordered the engine. I'm thinking of using his brand new AM-20T which is supposedly lighter than Lycoming IO540, it's very energy efficient and it used MOGAS. Here's the fuel consumption result from his test.

AM20T fuel consumption:
% power HP GPH
75% 195 13.3
65% 169 11.0
55% 143 9.3
45% 117 7.6

The spec on their website is 260HP. Not sure why the test is on the lower end of the spectrum. Its a conversion brand new engine from suzuki, if I'm not mistaken. Very interesting engine spec though.

http://aeromomentum.com/am20t.html

Any comment on both of my questions? I'm curious to hear your thoughts. Many thanks.
 
If you have the money, go quick build with a factory Lycoming and the Hartzell prop.

The 10 is a big project and after all that effort and expenditure, you'll be really glad to have followed a proven solid recipe.
 
lycoming engine and propeller

i strongly reccomend a tried, true and reliable Lycoming engine. After all that building work why risk a problem when you have 3 of your friends/family on board.

I admire those that are working on alternative engines but I am not willing to risk my butt on an engine that has not been really put to the test through millions hours of real world experience.
 
Start building. QB is the way to go if you have more money than time.

Even with a QB, you're probably 2-3 years from needing an engine. In that timeframe, let someone else (or several someone elses) be the early adopters for the Aeromomentum engines and make your engine decision with their experiences in mind.
 
I went quickbuild with no regrets at all. In my view it will pay for itself by putting the plane in the air 1-2 years early. What is flight time worth?
 
While I do not fall in the category of more money than time..... I am doing a QB wing. Travel work schedule and a 18 month old at home warrants it for time. I am lucky to have a friend/building partner working on the fuse to bring it up to QB stage, so I will essentially have a full QB kit. If purchasing outright I probably would not have the finances to go with the QB fuse. I've been told if you do one QB kit out of the mix, do the QB wing due to its level of completion.
 
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Like Bob said, the QB kits are primed with a wash primer.

QB's are a great deal if you have the money, why not? Unless you just love the build process.

To build a standard build 10 is gonna take at least 2400 man hours and that is without much deviation from the standard Van's plan. Any modifications you do are going to take longer.

Almost anyone can build a plane but if hand tools, mechanical concepts, reading and following technical documents, assembling complex assemblies, etc. are hard for you, expect more hours. On the flip side if all that stuff comes very easy, you may get away with a few less hours. You may be great at mechanical concepts but stink at electrical and vice versa or you may be great or poor at both. The 10 has a great deal more composite work required with the cabin top and doors. This can be a huge learning curve for some.

Fancy interiors, fancy panels, and alternative engine installs can drive up the work required drastically. Builder paint jobs can also pile on the hours.

Jason's videos are fairly representative on what it takes to build a plane. The only thing is understanding how many hours of work are really behind a few minutes of time lapse video.
 
While I do not fall in the category of more money than time..... I am doing a QB wing. Travel work schedule and a 18 month old at home warrants it for time. I am lucky to have a friend/building partner working on the fuse to bring it up to QB stage, so I will essentially have a full QB kit. If purchasing outright I probably would not have the finances to go with the QB fuse. I've been told if you do one QB kit out of the mix, do the QB wing due to its level of completion.

I am doing the same thing as Brad.... My slow build fuselage is being delivered next week, and I plan on ordering QB wings when I am 9 months or so away from flying. In my case, I currently have a 7A that I finished in 2012, and will need to sell it at some point in the build to fund my 10.

My goal is to "back-load" as much of the costs as possible to minimize the period of time I am without a plane.
 
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Start building. QB is the way to go if you have more money than time.

Even with a QB, you're probably 2-3 years from needing an engine. In that timeframe, let someone else (or several someone elses) be the early adopters for the Aeromomentum engines and make your engine decision with their experiences in mind.

Everyone's circumstances are different, but for the typical builder, Kyle is correct.

I did a -6A 20-25 years ago, the kind where they shipped you plans and a box of aluminum ore. I bought my 10 kit finished to the QB stage by another USA repeat RV-10 builder who thankfully (I guess) put generous AKZO on all the interior and fay surfaces. Even with a large, well-equipped shop and the occasional kitchen pass from Saucy Wench, I am 2.5+ years into my work on it and still gluing in windows, not yet on gear, no engine or panel on site yet. It's a huge time commitment, and QB / equivalent is the way to go unless you're young and/or poor.

ETA: Post #1111. This place is awesome. Thanks again, Doug!
 
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Thanks for the warm welcome Mike and many thanks for the info everyone. I'm glad that I found this forum. Y'all sounded very passionate with this Vans RV product and that's a good thing.

That's good to hear about the wash primer. Since I'm not a builder by trade and I really couldn't tell whether the inner parts were primed or left bare just by looking. I'm very thankful for the info. This will definitely help me solidify my decision on QB or legacy. I'm not a purist. I just want the darn thing to be done with so that I can spend more time flying rather than dinking around with the build. I just don't have the patience like Jason or some of you to go through the parts one by one, riveting thousands of rivets for the plane parts day by day. That'll absolutely drive me bonkers. I do enjoy the learning part though but once I have done the rivets number 200, I'm ready to move on. :) Hopefully with the QB, it'll help speed things up a bit.

As for the engine, yes I hear ya. That's one of the reason why I'm asking the question with the other engine. Although, as much as I should, I'm actually not too worry about the plane going down due to the engine failure because well, when it's my time, its my time. I can use the Lycoming engine and the possibility of failure is still going to be there. Even though may be a small chance or I should say smaller? :)

My only concern with other engines are more on the difficulty in installing the engine that's not built specifically for the RV-10 plane. Or perhaps the quality of the engine. Again, this opinion is from know nothing someone who's not a builder. However, I really like the idea of using Mogas instead of Avgas (My apology if I insulted someone. I'm really not trying to start a religious war as a noob in this forum :) ). It will help justify more of my flying time from the cost perspective. :) Kind of strange thing to be concerned about consider it's already going to cost me a fortune to build it but it is what it is. :) I like the aeromomentum engine also because it's a turbo engine with the ability to go beyond 260 hp if I wanted to while keeping the same weight of the engine and it doesn't hurt that it's a turbo engine as well. With lower gas consumption and lighter engine, that'll translate more to longer distance for me. The less hops I have to take to fly to SoCal to visit my parents the better the plane for me. :)

As for the prop, I was thinking of using the airmaster but when I did the research, I found out that Hartzell also have the composite propeller which IMHO is much lighter. Not sure whether it matters. Also I like Hartzell constant speed hydraulic system more than the airmaster electronic constant speed control. Any food for thought on the hydraulic vs electronic?

Yeah if all the QB parts are all primed, then I'll just go with the QB. I don't have a lot of money but at the same time my time is very limited with business travel and family. So, whatever helps with the speed of the build, will be the route I'll take. From practicality perspective, it'll cost me something, one way or the other.

I think when I'm ready to execute it, I'll go visit the factory for a tour and see it myself on the QB parts before I make the decision. My other concern is space. I don't have a hangar yet and hangar cost a fortune in Seattle area and most of them is quite a drive from where I live. Well, actually it's not that far away from distance perspective but to some of you who've been to Seattle, you know how lovely our traffic is. So I'm guessing, if I went with the QB, I'm gonna need a hangar ready to go right? My extra single car garage may not going to cut it. I'm speculating that there really is not much of a lot of building other than perhaps the empennage? At least that's how it looks like from the QB picture on Vans' website.

rv-7_quickbuild_lg.jpg


Comment?

Many thanks again everyone for the warm welcome and the help. :)
 
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Slow Build

I'll offer a different perspective. Although it took 8 years to finish my build :eek:, I was done with the airframe (less fiberglass) in 2 years. The slow build fuse, fully primed with Akzo, was done in not much more than the wait time for the quick build kit at the time. I really enjoyed that part of the build. The wings followed and while repetitive, they weren't too bad. I should mention that I had a Cherokee all this time, so I wasn't grounded while building. Once the airframe was done, I had to schlep it across the country for a job move, spent the next 4 yrs in a travelling job, had two kids, moved to an airpark :D and finally got down to finishing the thing. If I were to do it all again (and I might, don't tell the wife :rolleyes:), I'd go slow build again without hesitation. Wiring the panel took longer than building the fuselage, so if you're really looking to save time, the cost of a quick build kit, plus a plug 'n play panel is gonna add a good $50k to your build at least. That $50k was just enough to get me a hangar attached to the house! Just sayin...
 
Or perhaps do it the way you did it, Paddy. Buy other plane (used one. Been eyeing that Cherokee 6-300 for a while), ride it for 10 years or until whenever the RV-10 is done. Take the time with legacy and perhaps like what Kyle suggested, since it'll take that long to build the darn plane, the aeromomentum engine could be ready by then and I don't have to be the quinea pig. Or better, other new engine may have popped up by then. The priming part (even though, Vans already do the wash primer) still bothers me a bit. I'd like the normal Akzo slathered all over the inside of the frame than just the wash prime.

Not a bad idea. I can always sell the Cherokee and assume the lost (or gain) as money I'll have to pay no matter what if I had to fly the RV-10. and by taking the time to build it, I don't really have to buy all the RV-10 parts right away while I'm building it. Plus I can always use that extra 50k to load all the plane with all my dream toys. :) Although that may not fit what Bill said. Young and poor? Depend what's the definition of young and poor nowadays right? I could go both ways with the young and poor. LOL...


Thanks for the advise everyone.
 
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I'll add my experience to the list above. I went with the QB wings and fuselage for my RV-10, and am very glad that I did. The 10 is a very large and time consuming project, even with the QB. As for rivets, even with the QB you will be setting thousands of rivets by the time you are done. And I'm satisfied with the primer that Van's recommends and uses on the QB interior parts, and used the same primer for my empennage and other parts.

I believe the $50,000 estimate for QB and panel is way too high. The QB wings are $6200 extra and the QB fuse is $7475, so total extra for QB is $13,675. As for the plug & play panel, the cost will depend on what avionics you select. If IFR well equipped such a panel can cost $36,000, most of that is for the avionics, not for the panel shop work. So you might spend $3 - 5k for a panel shop doing the cutting and wiring, you won't save $36,000!

I personally would not consider installing an automotive engine in my aircraft. These engines are not designed to produce 70% power for hours at a time. They are designed for brief bursts of power for a few seconds of acceleration, followed by perhaps 15-20% while cruising down the interstate. They don't have dual ignitions and you have the additional complexity of water cooling and the need to install a PSRU "transmission" which is a frequent failure point. And if the engine is lighter, you will either need to move it farther forward from the firewall to maintain the designed CG point, or do some major redesign of the fuselage to get the plane into the design CG. For me, this extra work and risk isn't worth it. I also expect that an RV-10 with a non-Lycoming engine will be harder to re-sell and will have a lower resale value.

But at the end of the day, this is an experimental aircraft and so we each have the right build what we think is best. So have fun with your build, no matter what route you decide.

Cheers,
 
Avionics Shop

Where can you get an IFR panel done for $5k over the cost of the hardware? I'd love to have found that place when I was building!
 
A single car garage is sufficient to build any major component on an RV-10. Depending on the maximum dimension, you may or may not able to complete the engine/cowl/prop in that space.

For most folks, moving the project to the airport really slows progress compared to working at home. It generally increases discomfort and places you farther from a restroom, food, and all of those other conveniences of home. You won't need hangar space for years, other than to possibly store finished components.

If you have a driveway, you can temporarily fit the wings and tail there, then disassemble it the same day.

As far as mogas is concerned, there are plenty of people successfully burning it in lycomings. Realistically, Mogas isn't widely available at airports, so if you're building the airplane to travel, you're going to burn a lot of avgas anyway.

One more thought. You mentioned the risk of an alternative engine vs a Lycoming. I don't think many of us would choose to fly ourselves or ourselves plus passengers behind an engine we don't have faith in. That's where many alternative engine users meet their Waterloo. Sure, the engine runs, but it doesn't cool well, or the redrive is making metal, or there is an intermittent miss that is hard to track down. So the alternative engine guys often (not always) end up doing a tremendous amount of development work on their installation before they are truly comfortable with the airplane. Plenty of times they either walk away and sell the project, or convert it to a purpose built aircraft engine. You take a big financial hit when you do that. Something I haven't seen mentioned with regard to Aeromomentum is how they have addressed harmonic vibration, thrust bearings, and all of those things you have to address when you take an engine and convert it to aero use. Those are tricky issues to resolve
 
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Reading your comments (?...after 200 rivets you?re ready to move on...?) makes me wonder if you?d be happier buying someone else?s RV. Personally I thought building was a great, enjoyable experience, but not everyone feels that way. And if you don?t, it will turn into work. My suggestion: invest in the tail kit and basic tools. If you don?t like it, well, you haven?t lost a huge amount.
 
I personally would not consider installing an automotive engine in my aircraft. These engines are not designed to produce 70% power for hours at a time. They are designed for brief bursts of power for a few seconds of acceleration, followed by perhaps 15-20% while cruising down the interstate. They don't have dual ignitions and you have the additional complexity of water cooling and the need to install a PSRU "transmission" which is a frequent failure point. And if the engine is lighter, you will either need to move it farther forward from the firewall to maintain the designed CG point, or do some major redesign of the fuselage to get the plane into the design CG. For me, this extra work and risk isn't worth it. I also expect that an RV-10 with a non-Lycoming engine will be harder to re-sell and will have a lower resale value.

But at the end of the day, this is an experimental aircraft and so we each have the right build what we think is best. So have fun with your build, no matter what route you decide.

Cheers,

I agree with most of your post, however to say automotive engines are not designed to operate at 70% power for hours at a time is not factual and contrary to the actual testing paradigm employed by most automotive engine manufacturers. If you don?t like the idea of using an automotive, that?s fine by me - everyone is entitled to their opinion. But they do work well in the role of aviation with many of them in active service on many aircraft, even ones here on VAF.
 
My Dos centavos. The fuselage is fun to build. Lots of gratification and seeing results as you build. Legacy build let’s you plan wiring and do other things like A/C hoses and/ or sound insulation. (I did both).

Wing is relatively boring and repetitive and a pain to store until final assembly. You can do the fuselage after the empennage by ordering the spar box kit with the fuselage kit and save the wings for last. I went QB on the wings.

When I started building, there were two “hot” engines with impressive (in theory) numbers at attractive prices. (One Subaru, one Corvette). At first I was attracted to the glossy brochures, but the old salt brain trust talked me into staying legacy Lycosaur, and boy, in hindsight, am I glad that I did. Neither company is still around in its original form leaving a bunch of frustrated orphans.
I am glad that next level experimenters are out there. They are a vital part of our culture and maybe someday a “real deal” might emerge, but personally, I wouldn’t buy into anything with a two digit serial number or less. Caveat emptor.
 
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First, pleas study aircraft building techniques. Aluminum does not rust.

I really enjoyed the four years and two months of assembling my RV-9 but when I looked at the numbers, I paid myself something like $8/hr to do it myself.

You have to ask yourself if you enjoy building or do you want to go flying.

Build the tail kit and then decide which way you want to go.
 
Wow. You guys are all very well spirited when discussing this option. I can feel the passion even by just reading your comment. I hope I haven't just started a civil war with my curiosity. Thanks everyone.

So, yes thanks as well for the input Bill. Yes I do know aluminum doesn't rust, it corrodes. It's just a lazy way of me describing corrosion. My bad. Dang, the details that you guys pick on based on my comment is amazing and I mean it in the most sincere way. :p

So when I said, I got bored passed 200 rivets, I don't mean it literally. I just meant to say that I'm not good at doing repetitive stuffs. My brain is just wired differently and what ended up happening most of the time is that I ended up trying to find the more efficient way to do thing (AKA: Shortcut :)). That's all. Not shortcut in a negative way like shortcut not doing things that I have to do but I didn't do just because I'm lazy. Well the lazy part is still there but that's what drives my brain to find a way to do things more efficiently. Anyway, enough of my soapbox.

Well thanks for all of the suggestions. Very good input indeed. Bob, to answer your question whether I'll be happier buying someone else's RV, I'd say big "NO" and that's part of the reason why I asked whether I should do QB or legacy. I may not be able to build it perfectly myself but I trust what I build better than someone else's. At least I know where the potential issue that I may have when I build it, where if it's someone else's built, god knows what's behind it. I'm not saying that they don't build it right. I just don't like catching surprises that I'd have known if I built it myself.

One example. I always thought that changing brake pads and brake rotors for car in general is a pain in the ***. Out of curiosity one day, I did try to change the brake pads for my car myself. Guess what I found out. Some other mechanic who replace my brake pads in the past (which I can't remember who) install the brake pads and forgotten to put a couple of the spring back to hold the brake pads. That could end up catastrophic to me, or not but that doesn't matter. So I forced myself to learn how to change the brake pads and all the rotors for all my cars since. Annoying, yes. Pain in the ***, absolutely. But at least I live with the satisfaction of knowing that it's being done correctly. I know plane is more complex than my **** brake pads but I hope you got my point.

I'm not saying that what Vans build for the RV-10 is troublesome. I'm just saying that if I built it myself, I'd have known all of those nooks and crannies down to the details and I don't have to second guess what other people did or didn't and be paranoid about it. My challenge just like everyone else is of course, "Time". I think of myself as "do it once, do it right, or don't do it" person. Not to a point of being a perfectionist but I still would like to get it done right. Especially for something like an airplane where if I screwed it up, it could kill me and my passengers. But just like anything else in life, there's a trade off. I travel a lot and not being able to touch the building process at least an hour a day will slow down the progression of the build. Plus the most important part, my family time. We all only have 24 hours a day. No matter how we slice it, it's still 24 hours/day. Something has to give. That's the $100 million dollars question, right?

BTW, thanks Kyle for the input on single garage. I agree with you. As much as airport hangar is a bigger space, having to go there to do the work everyday will slowly diminish it to become once a week, then once a month, then once a year. Then I got frustrated that the project never get completed. So I guess I'm converting my single car space to become my lab then. :) I can always move the other 2 cars out of the other garage spaces if needed.

Sorry I digress. So from tools perspective, I'll say it'll cost the same for me whether I do 500 hours work or 2500 hours work, so there's no saving there. I still need to buy the **** tools. But I'll try your suggestion though Bill. Try the Empennage first since there's no QB for that and I have to build it no matter what. If I could manage my time to do it, I'll continue buying the rest of the pieces. I hear you all about buying the boring part such as wing. The issue is, after watching Jason's video on his journey to build the RV-10, there's something in the wing build that I know if Vans is the one who build it in QB, I'm not going to be happy. Again, I'm not saying that the quality is not good. It's just that there are a couple of things that I want to do that's different with the way Vans build it. Such as for example, adding a conduit in the wing instead of using the grommet for example. That has always been a preference of mine, even with my home. I've always complaint that the previous home builder didn't use enough conduit in my house and when it comes time to do some upgrade, man, it's such a pain in the ***. That's just one example. But back to the question, do I want to go through all the painful 1 rivet at a time? Hmmm :confused:.

As you can tell, I'm still trying to decide whether I should just suck it up, build it the way I want it, learning everything and squeeze whatever time I have to work on the plane, or just say the **** with it, and buy the QB version.

Back on the engine discussion. Thanks for the input Dave. Here's my comparison. Lycoming IO-540 260 HP about 47.7k per engine as of today. Aeromomentum AM20T, as of a week ago, I got quoted for 18k. Dang, the difference. Lycoming TBO normally is around 2000 hours, right? With average cost for Lycoming TBO? Around 10k, give and take a couple hundreds. Aeromomentum, TBO is currently at 1500 hours and I was told when the TBO time has come, it'll probably cost less than 5k by replacing the long block and a couple of other parts and the engine is back to almost brand new with another 1500 hours. Of course I'd expect the value of the plane to be lower. That's a reasonable assumption cuz when you use a cheaper engine, you can't expect the plane to be sold at the same price like the RV-10 with Lycoming. Just the way it is and I have no beef with that. Plus knowing myself, if I spent this much time building the **** plane, I'll probably own it till I die. By then it's my kids' problem. LOL. Plus even if I assumed I fly say 200 hours a year, that'll still take me like 7 years before I have to TBO the engine which by then, a new type and more efficient engine is going to enter the market. So I'm not too worry about the company disappearing. It's an auto conversion and any car mechanic can fix it. The way I see it, that's the beauty of auto conversion. :) FYI, the AM20T is still in a test stage and Mark said, it will hit the alpha stage by the end of this year I believe. Not that I'm in hurry anyway. I have tons of time to think.

Anyway, sorry for the long post. I thought the least I can do is to respond to all of you kind people who have been generous with your advise by taking your valuable time away from your busy day to day life activities to answer my annoying questions. Really appreciate the thought. I learn so much from y'all. So if this has not become a civil war, please do continue with the passionate conversation. I enjoy learning from many different perspectives. Have a wonderful weekend everyone and happy flying. :D
 
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I agree with most of your post, however to say automotive engines are not designed to operate at 70% power for hours at a time is not factual and contrary to the actual testing paradigm employed by most automotive engine manufacturers. If you don’t like the idea of using an automotive, that’s fine by me - everyone is entitled to their opinion. But they do work well in the role of aviation with many of them in active service on many aircraft, even ones here on VAF.

+1

Many common auto engines are put in tough duty when installed in large boats (most have stock auto auto engines with adaptions for prop drive and cooling). THey typically run around 3000-4000 RPM and high load (i.e. high MAP). The load is comparable to aggressive acceleration in a car. They run most of their lives in this state and there are no issues with longevity.

I agree with others that it is not the engine that is the issue, it is all of the adaptation, including PSRUs that cause most of the trouble. Though it does seem that many also struggle with dialing in the mixture and timing that causes problems. Engines running under higher loads are intolerant of lean mixtures and agressive timing.

Larry
 
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Back on the engine discussion. Thanks for the input Dave. Here's my comparison. Lycoming IO-540 260 HP about 47.7k per engine as of today. Aeromomentum AM20T, as of a week ago, I got quoted for 18k. Dang, the difference. Lycoming TBO normally is around 2000 hours, right? With average cost for Lycoming TBO? Around 10k, give and take a couple hundreds. Aeromomentum, TBO is currently at 1500 hours and I was told when the TBO time has come, it'll probably cost less than 5k by replacing the long block and a couple of other parts and the engine is back to almost brand new with another 1500 hours. Of course I'd expect the value of the plane to be lower. That's a reasonable assumption cuz when you use a cheaper engine, you can't expect the plane to be sold at the same price like the RV-10 with Lycoming. Just the way it is and I have no beef with that. Plus knowing myself, if I spent this much time building the **** plane, I'll probably own it till I die. By then it's my kids' problem. LOL. Plus even if I assumed I fly say 200 hours a year, that'll still take me like 7 years before I have to TBO the engine which by then, a new type and more efficient engine is going to enter the market. So I'm not too worry about the company disappearing. It's an auto conversion and any car mechanic can fix it. The way I see it, that's the beauty of auto conversion. :) FYI, the AM20T is still in a test stage and Mark said, it will hit the alpha stage by the end of this year I believe. Not that I'm in hurry anyway. I have tons of time to think.
:D

It appears that AMT20 is 150 #'s lighter than the 540. You will have a significant W&B problem.

Larry
 
Larry. You are correct. The AM-20T is lighter than Lycoming. I don't think it's by that much. Thus, they don't have the kit for Rv-10 yet and it needs to be built and weighted to balance the CG.
 
What a fun problem

It appears that AMT20 is 150 #'s lighter than the 540. You will have a significant W&B problem.
Larry

Considering that the normal comment is that the alternative engine to a Lycoming weighs too much for the power, it’s a fun problem to have it “too light”. It’s dimensionally smaller than the 540, so it could be moved forward a little bit. You could skip the composite pro and go with the heavier metal prop, use a prop extension, mount batteries on the FW, yada, yada, yada. It can be done. Just need to set “builder” skills to the side for a minute and focus on “experimenter” skills.

One other thing, Time Before Overhaul is a regulatory construct and has no value or legal influence in the experimental world, or certified part 91 operations for that matter. Even more so, with most pilots flying much less than 100 hours per year, it’s the seals hardening and cracking that limit the age of most engines. Somewhere between 12 and 20 years is the real life of your engine, irrelevant of the arbitrary assignment of TBO. If you fly your airplane several hundred hours per year and maintain it well, it will last multiple thousands of hours. I had a set of IO-520’s (TBO 1700 hours) with close to 3000 hours on them before OH’d.

I would be less concerned with a TBO assignment, which is going to be a very conservative number on a new engine package, and more on what fits your needs and installation.
 
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I came late to the discussion. The old wisdom for homebuilts has always been "if you want to fly, buy. If you want to build, build." That covers the people who regret that their aircraft can't be built in X timeframe because LIFE. So they often give up when it's going to take longer to get in the air than they had anticipated. In the OPs case, it sounds like he partially enjoys the building, except that some of the tasks are boring. We all have that problem and building a QB is not going to entirely alleviate it. You will still have thousands of holes to drill, deburr, and rivet. You will still have to do all the glass work, including the sanding, priming, sanding, etc. Building an aircraft is detail oriented and many of those details are boring at best and frustrating at worst (says the man who is having to disassemble his entire mid fuselage section). But if you don't have the strength of will to push through those details, then building may not be for you. One idea may be to get yourself a building partner who can ease some of the burden and help motivate you.

As for the engine question, unless you really want to spend the time to engineer and build, there really is no choice. The RV-10 is currently only produced for the Lycoming IO-540. That's not to say there are no alternatives, but they require modification to the kit and extra time and effort to install, not to mention any operating issues that may arise. Again, if your object is to build and experiment, then by all means do. But if you want to shorten the time to get it airworthy, then you will want to minimize deviations from the plans.
 
Alternate engine

Unless you were born with a box wrench in your hand, I would not consider an alternate engine for the RV10. JMHO. I worked race cars for years, and still would not consider it due to the work involved it making the firewall forward stuff all play nice.
 
LeDude,

When I raced cars, we always said, if you build it light, you can add weight where you want. That is a GREAT position to be in. However, if you build it heavy, you have no idea where to remove the extra weight from.

The members of this board have seen auto conversions come and go over the years with the same promises as you have mentioned. Thus, we are always a bit more than skeptical.

Remember, auto engines are not designed to run at 75 or even 55 percent power all the time. The normal duty cycle for an auto engine is up and down, never continuous at one power setting. Even on the highway, with the cruise set, an engine is very lightly loaded.

Aircraft engines, on the other hand, are designed to make TBO while spinning on the redline at 75% power. That is a HUGE difference in duty cycles.

Yes, the IO-540 is expensive but so is building. I was stunned to realize I spent well north of $10,000 just on tools by the time I was finished and I'm still buying tools AND I've been flying for over 11 years now.

This airplane building thing is a lifestyle more than anything. Either you embrace it or you don't. Hopefully your spouse is on board because if she isn't she won't be your spouse much longer. As for your friends, you will be exchanging them for others who are builders and/or fliers. That is just the way it seems to go.
 
Remember, auto engines are not designed to run at 75 or even 55 percent power all the time. The normal duty cycle for an auto engine is up and down, never continuous at one power setting. Even on the highway, with the cruise set, an engine is very lightly loaded.

Aircraft engines, on the other hand, are designed to make TBO while spinning on the redline at 75% power. That is a HUGE difference in duty cycles.

Not the "car engines can't hold an airplane duty cycle" canard again <facepalm>

The reason "traditional" airplane engines tend to be fairly successful when installed by amateur builders, yet we hear stories about troubles with so many alternative engines, has little to nothing to do with the duty cycle on the engine.

Rather, people installing traditional Lycoming/Continental are standing on the shoulders of decades of industry practice and millions of man-hours and dollars spent by NASA, NACA, and the engine/airframe OEMs on the specific topic of "how to properly and optimally install air-cooled piston engines and their accessory parts in airplanes". We can buy our Lycoming/Continental/Clone, obtain a reasonably-complete FWF "package" with instructions from several vendors, or if nothing else at least raid a certified aircraft for parts and duplicate the installations on thousands of other aircraft.

And even at that, look at how many of these "standard" engine installations require tweaking and adjustment after they start flying. How many people have high oil or cylinder head temperatures? How many people say they have hot-start troubles while others with the same engine claim they don't?


By contrast, someone installing an auto conversion usually does not have all that nice guidance material. Some past vendors have attempted (with debatable levels of success) to provide complete "package" engines, but for the most part alternative engine installations are much more individualized and often require things like reduction gearboxes, liquid cooling systems, and electronic engine controllers, that don't have anywhere near the same installed user base. Someone installing such an alternative engine will likely have very little material to base their installation on, relative to that which is available to someone installing an O-360. If you aren't very familiar with those topics, you might be facing a very steep learning curve. You'll definitely be doing a lot more "figure it out on your own" and experimentation with a conversion installation.

In short:
it is all of the adaptation, including PSRUs that cause most of the trouble. Though it does seem that many also struggle with dialing in the mixture and timing that causes problems. Engines running under higher loads are intolerant of lean mixtures and agressive timing.


I think it will take three things for a conversion engine to be successful on the market.

1. A complete FWF package with good directions--think RV-12/14 level kit and manual, but for an engine. And complete meaning mount, engine, gearbox, cowling, any accessories, and everything done to the level of "insert tab A into slot B".

2. Extensive testing of the same configuration.

3. A price point below a "standard" Lyclone installation, or significant improvements in power for the same cost and weight.

Unfortunately, the costs involved in producing the first two are likely to prevent the third from happening, short of a Musk/Bezos style sugar daddy getting involved.


Back on the main subject, there's lots of tedious, boring work that will need to be done regardless. But make sure your significant other is on board--otherwise, you may well wind up a few years down the road with no airplane and no SO.
 
Auto Engines

I work for a car company. A couple of decades ago, we had a senior executive who happened to be a keen pilot. During his tenure, a project was launched to build a light single around our top of the line V8 engine and certify it. That engine was a clean sheet design and was simply superb, both in performance and reliability. In fact the engine eventually received FAA certification, which was a huge milestone in the project. The airplane project got as far as a flying prototype but was shelved for a number of reasons. From what I understand, the engine was bulletproof, the airframe state-of-the-art, and the resources available to put the two together virtually unlimited. Yet, the project was shut down. A few years later, I was in the warehouse where we kept all the secret car stuff and came across the airframes and equipment. Guess what was on the shelf next the fuselage? You guessed it - a good 'ol IO-540 brand new, still in it's crate. Long story short - a Lycosaur is a crude, heavy, antiquated and expensive motor that's just about perfect for powering light airplanes. The design is incredibly tolerant in terms of cooling, fuel delivery, power settings and many other things that we as builders don't even think about. Add to that the direct drive configuration (no PSRU) and it turns out that the old relic is kinda hard to beat.
 
But

But you really didn?t say WHY the project was shelved. I would speculate that it had VERY LITTLE to do with the engine or airframe and EVERYTHING to do with the lawyers. I can go down to the local hydraulic shop and get any kind of hose I want made, as long as I do not say it is for an airplane. That one word shuts evrthing down and closes every door. Back to the point, it wasn?t that the Lycoming was better, it was most likely the lawyers and potential liability...
 
?

someone installing an auto conversion usually does not have all that nice guidance material. Some past vendors have attempted (with debatable levels of success) to provide complete "package" engines, but for the most part alternative engine installations are much more individualized and often require things like reduction gearboxes, liquid cooling systems, and electronic engine controllers, that don't have anywhere near the same installed user base. Someone installing such an alternative engine will likely have very little material to base their installation on, relative to that which is available to someone installing an O-360. If you aren't very familiar with those topics, you might be facing a very steep learning curve. You'll definitely be doing a lot more "figure it out on your own" and experimentation with a conversion installation.

In short:

I think it will take three things for a conversion engine to be successful on the market.

1. A complete FWF package with good directions--think RV-12/14 level kit and manual, but for an engine. And complete meaning mount, engine, gearbox, cowling, any accessories, and everything done to the level of "insert tab A into slot B".

2. Extensive testing of the same configuration.

3. A price point below a "standard" Lyclone installation, or significant improvements in power for the same cost and weight.

Unfortunately, the costs involved in producing the first two are likely to prevent the third from happening, short of a Musk/Bezos style sugar daddy getting involved.


Back on the main subject, there's lots of tedious, boring work that will need to be done regardless. But make sure your significant other is on board--otherwise, you may well wind up a few years down the road with no airplane and no SO.
Not the "car engines conversions will work" canard again <facepalm>

Seriously, we have a new builder who is drinking the conversion cool-aid. You won't find a bigger fan of the idea than me; however, the truth of it is that we don't have a Musk/Bezos funding such projects.

The people funding these conversions typically are doing it on a budget and a small budget at that. Thus, they don't put them on a dyno and run multiple test samples to destruction and then fix what fails.

Typically, that test until destruction cycle occurs on the front of a customer's plane.

If the OP decides to install an auto based engine, great, I will be the first to wish him luck and cheer him on. However, he needs to understand what he is getting into.

I do not want to read about another alt-engine RV crashing.

If you doubt me, look at how many alt-engine RV's have been converted to aircraft engines.

My business partner was the second person to fly behind a rotary and has almost 500 hours on it. He also has more RV glider time than anyone I know. His attitude is, if you like to tinker, put an auto engine up front. If you like to fly, put a Lycoming up front.
 
I would speculate that it had VERY LITTLE to do with the engine or airframe and EVERYTHING to do with the lawyers.

Speculation of course is optional and free :). Serious R&D, on the other hand - aint! As an engineer, I know you have an appreciation for that. Rest assured, if there was a buck (or a yen) to be made by putting those power plant packages into production, even without the airframes (which was an ancillary goal as a halo marketing effort for the cars with the same motor), it would have been done. I was told that scale of the effort required to deliver automotive level reliability between the motor, PSRU and prop just wasn't feasible from a cost perspective. The project never even made it to the lawyer stage. The only time the lawyers were involved that I know of was when some RV-10 builder tried to get his hands on that new 540 in the crate :p. He was told the motor and everything else associated with the the project was slated for destruction :(
 
Speculation of course is optional and free :). Serious R&D, on the other hand - aint! As an engineer, I know you have an appreciation for that. Rest assured, if there was a buck (or a yen) to be made by putting those power plant packages into production, even without the airframes (which was an ancillary goal as a halo marketing effort for the cars with the same motor), it would have been done. I was told that scale of the effort required to deliver automotive level reliability between the motor, PSRU and prop just wasn't feasible from a cost perspective. The project never even made it to the lawyer stage. The only time the lawyers were involved that I know of was when some RV-10 builder tried to get his hands on that new 540 in the crate :p. He was told the motor and everything else associated with the the project was slated for destruction :(

So how heavy was that Lexus/Toyota V8 and how much power did it produce?
 
Remember, auto engines are not designed to run at 75 or even 55 percent power all the time. The normal duty cycle for an auto engine is up and down, never continuous at one power setting. Even on the highway, with the cruise set, an engine is very lightly loaded.

Aircraft engines, on the other hand, are designed to make TBO while spinning on the redline at 75% power. That is a HUGE difference in duty cycles.

This statement is not true. You?re obviously opposed to using an automotive-based engine in an airplane and enjoy what you?ve built - which is fine, but to say they are not able to employed for this purpose as a matter of fact is false and continues to propagate this myth. Even more so, what wears an engine out is not the continuous at-power operation, but the duty cycles themselves. If operated at a continuous rpm and load, just about any engine will last longer due to the stabilized oil film and temperatures of components.

There have been several automotive adaptations for aircraft that have, and continue, to work well. Probably the greatest modern example of a repurposed automotive engine in an airplane is the Diamond twin engine diesel aircraft using a Mercedes engine.

The ?Fear, Uncertainty and Doubt? spread by saying you don?t want to hear about aircraft with alternative engines crashing is a display counter to experimentation. The flaw with most alternative engine installations is just that - not the engine, but the installation.

While the vast majority of Van?s aircraft are constructed by ?builders?, please don?t discourage ?experimenters? out of your own fears portrayed as fact. It?s this continuing negativity that makes me consider using an ?alternative? engine on my new RV10 if for no other reason than to demonstrate the viability of it.
 
Well said.

Very well said.

It is the experimenters that lead the way and make strides in progress possible, not the followers...
 
Remember, auto engines are not designed to run at 75 or even 55 percent power all the time. The normal duty cycle for an auto engine is up and down, never continuous at one power setting. Even on the highway, with the cruise set, an engine is very lightly loaded.

Aircraft engines, on the other hand, are designed to make TBO while spinning on the redline at 75% power. That is a HUGE difference in duty cycles.
This statement is not true.
...
Even more so, what wears an engine out is not the continuous at-power operation, but the duty cycles themselves. If operated at a continuous rpm and load, just about any engine will last longer due to the stabilized oil film and temperatures of components.

That is exactly my point. I may be being pedantic, but the idea that "airplane engines can maintain 75% power for long periods but car engines can't" is a load of manure, and it's that part specifically that I'm objecting to. Pretty much any piston engine in normal use will sustain rated power for ridiculous periods of time, so long as fuel and ignition are properly set, and you maintain sufficient lubrication and cooling. Go look at the testing done on mass-production car engines and you'll see them running wide-*** open for hundreds of hours.

You may be interested to know that Part 33 requirements for piston engines, and specifically 33.49, only specify a 250 hour endurance test--a series of cycles between full power and various cruise settings.

The rest of my statement is not intended to encourage or discourage anyone. I'm merely trying to show that there's a lot of work that goes into designing and building a proper firewall-forward installation. Using a traditional engine, and especially the engine supported by the kit manufacturer, means that builders can leverage all of the work done previously by others throughout the industry, over many decades.

What I'm trying to get at, is if you're going to try and encourage someone to go the traditional engine route, then cite the right reasons instead of repeating old wives' tales.


For full disclosure, I will be using an O-360 with an electronic fuel injection package. As interesting and professionally challenging as I would find it to work on an engine conversion, I've chosen to use a traditional engine as the "base" plus a popular alternative fuel/spark system, because I can leverage others' past experience with both and get many of the benefits I want without having to go whole hog on a conversion.



On the topic of the engine that never went into production: something a lot of people don't realize is that you don't just have to get the design itself certified. You also have to get the production line certified*, to include maintaining incredible volumes of records and paperwork, and setting up entire portions of your production and quality-control groups the way the FAA wants you do do them. Liability concerns may have played a part, but I suspect a large portion of the decision probably hinged on the FAA not allowing this company to just divert engines off their normal production line for aircraft use. The FAA would probably want an entirely separate and isolated line, with completely different QC and recordkeeping procedures than the rest of the company used. And I suspect all of the supplier components and subcomponents would be subject to similar restrictions, or at least face more severe ones relative to auto-industry norms.


*okay, well, technically you don't have to get a production certificate, but not doing so likely becomes more expensive once you get out of single-digit production numbers...
 
As a lifelong motorcycle rider I have seen the Chinese reverse engineer half of Honda Motor Company’s engines. They sell for dimes on the dollar. Im surprised we have not seen this with Lycoming engines. Im not promoting this, just surprised. Yes they can build poor quality but they can also build excellent quality. They build engines for several BMW motorcycles at the Loncin plant.

Also as a side note to the current discussion, Lycoming considers its engines at TBO at the earliest of the published TBO hours or 12 years, whichever comes first...
 
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As a lifelong motorcycle rider I have seen the Chinese reverse engineer half of Honda Motor Company’s engines. They sell for dimes on the dollar. Im surprised we have not seen this with Lycoming engines. Im not promoting this, just surprised. Yes they can build poor quality but they can also build excellent quality. They build engines for several BMW motorcycles at the Loncin plant.

The reason there hasn't been a largely competitive engine to the Lycoming IO-540 in its purpose is not reliability or capability - it's simply economics. The economics of liability, research, development and marketing. Consider how many Lycoming engines are produced in a year, and then know that is about one day's production for even the lowest volume car manufacturer. Rotax recently posted a news item that they achieved their 15,000th 912 engine production and over 30,000 of the 582's over 40 years. Toyota makes about 14,000 every work day.

It's all about the numbers...mostly financial numbers - not aviation vs automotive purpose.
 
Quick Build or Legacy for RV10

You can see that auto engine conversions create quite a discussion thread.

Here are a couple other thoughts not mentioned so far.

You should see if any company will insure a 10 with an automotive engine and if so, what is the cost. If I ran the compnay, I would not.

If have been to a thousand airports across the US, Canada, Bahamas, Alaska, and I recall only a handfull that had mogas. The ones that did were no big savings.

You should consider resale value. I personally know 3 builders just in my town that installed auto conversion engines only to abandom them after a couple years of frustration. They then installed Lycs. I would tell anyone asking my advice (built two) to never buy an auto conversion.
 
You can see that auto engine conversions create quite a discussion thread.

Here are a couple other thoughts not mentioned so far.

You should see if any company will insure a 10 with an automotive engine and if so, what is the cost. If I ran the compnay, I would not.

If have been to a thousand airports across the US, Canada, Bahamas, Alaska, and I recall only a handfull that had mogas. The ones that did were no big savings.

You should consider resale value. I personally know 3 builders just in my town that installed auto conversion engines only to abandom them after a couple years of frustration. They then installed Lycs. I would tell anyone asking my advice (built two) to never buy an auto conversion.

What an interesting perspective. I personally know one builder (me) who used a corvair engine in their airplane. It was a fun build and the airplane flew well. I then sold it for a fair price to another who continues to enjoy it many years later! Crazy.

Insurance: I’ve built a few experimental airplanes - I’ve not yet been asked by the insurer which engine my airplane has. I put this myth in the same box with the one about insurers denying claims because the engine was over TBO (certified aircraft).

Gas: I fly my airplane almost daily and buy fuel at the local station and then just fuel my airplane from my truck. I’m not sure why fuel type is that relavent to lycoming versus automotive based engines considering you can run mogas in many Lycs, but being able to burn mogas as well as avgas adds options, and it certainly saves me money (as in more than $1 per gallon compared to the 100LL at the airport) in addition to not having to deal with leaded fuel.

Resale: I don’t really care. I built (and am building again) for myself. If my airplane is worth 20% less than a comparable one built exactly to Van’s plans, so be it. I will likely have spent even less building it and enjoyed it either way.

There are always naysayers, but fortunately we still have a little freedom left to choose how we want build our own airplanes.

My advice is to build it the way you want and enjoy it.
 
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