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Honda 1.8L on RV6A Now Flying!

Jim,

Yes. I know they also make heat shields for the turbine housing too. It would be good to put some temp sensors in there to get some data to see what is really happening. But right now I just need to try to stay focused on getting it flying!

Charlie
 
Charlie, interesting project!

I've been curious what all goes into adapting an automobile engine to work in an airplane. On the surface, seemed as easy as plopping it in and putting a reduction drive between the engine driveshaft and the propeller, but obviously things are never that easy haha.

I'm curious: what do you think of Mercedes' M139 2 liter engine outputting 416hp? https://en.wikipedia.org/wiki/Mercedes-Benz_M139_engine

Seems like it would be the perfect automotive engine to stick in a plane? It's a Mercedes engine so you know it's going to be very reliable. And it's a 4 cylinder only 2.0 liters that is producing over 400hp. My guess is that weight will be the biggest problem? I believe it weighs 385 lbs. But given all of that power, the weight should be easily overcome so I suppose the real enemy will be CG?

Also, I'm no airplane engineer but how does one increase MTOW? Will extra power increase MTOW or is MTOW dictated by something else in the structure of the plane? Or will engine power increase MTOW slightly, up until you reach structural limits of the airframe?

So if engine power will increase MTOW then you don't have to worry about the extra weight of the engine, except for the CG, is that right? And then could you just add counter weights to rebalance the CG?
 
Charlie, interesting project!

I've been curious what all goes into adapting an automobile engine to work in an airplane. On the surface, seemed as easy as plopping it in and putting a reduction drive between the engine driveshaft and the propeller, but obviously things are never that easy haha.

I'm curious: what do you think of Mercedes' M139 2 liter engine outputting 416hp? https://en.wikipedia.org/wiki/Mercedes-Benz_M139_engine

Seems like it would be the perfect automotive engine to stick in a plane? It's a Mercedes engine so you know it's going to be very reliable. And it's a 4 cylinder only 2.0 liters that is producing over 400hp. My guess is that weight will be the biggest problem? I believe it weighs 385 lbs. But given all of that power, the weight should be easily overcome so I suppose the real enemy will be CG?

Also, I'm no airplane engineer but how does one increase MTOW? Will extra power increase MTOW or is MTOW dictated by something else in the structure of the plane? Or will engine power increase MTOW slightly, up until you reach structural limits of the airframe?

So if engine power will increase MTOW then you don't have to worry about the extra weight of the engine, except for the CG, is that right? And then could you just add counter weights to rebalance the CG?

There is so much more to adapting an auto engine to aircraft than just plopping it on with a gear reduction. There are heat issues, lubrication, redundancy problems. they can be addressed, but when it comes down to it, the engine wasn’t designed for that application. I can imagine the engineer that designed whatever auto engine you are using , he would stomp his feet and pull his hair out saying, “if I knew that you wanted to do THAT with the engine, I would have DESIGNED it differently!”I have yet to see a successful auto engine conversion.. yes, people have flown auto engines on planes, but there is always problems that seem to take lots of time money and lack of promised performance.. eventually the plane either gets totaled, scraped, sold, or converted to an aircraft engine. Please someone prove me wrong and show me a successful plane with an auto conversion. If they were so wonderful, there would be a lot of them out there. There is so much more to an engine than water cooling, and prob reduction drives. Car engines don’t have the surface area on the rod bearings, or the beefiness in the crank and rods that aircraft engines do. Aircraft engines and their crank, rods and bearings are tremendously oversized for their hp load..low surface speeds on the bearings, wide crank journals, all add to their reliability. This isn’t meant to poopoo on the original poster and his project.. I support others experimenting with.. well, experimental aviation. I think it’s great that he’s doing something out of the box and having fun and learning from it. I was just addressing the guy who thought it may seem simple..

As for your MTOW question, there is a lot that goes into the max gross weight. One simple thing that I can think of is the main spar is only designed to hold so much weight, plus allowable “G” loading. Other factors to consider are fatigue cycles, motor mount, fuselage stringers etc...So no, you can’t safely increase takeoff weight based on more engine HP.
 
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Charlie, interesting project!

I've been curious what all goes into adapting an automobile engine to work in an airplane. On the surface, seemed as easy as plopping it in and putting a reduction drive between the engine driveshaft and the propeller, but obviously things are never that easy haha.

I'm curious: what do you think of Mercedes' M139 2 liter engine outputting 416hp? https://en.wikipedia.org/wiki/Mercedes-Benz_M139_engine

Seems like it would be the perfect automotive engine to stick in a plane? It's a Mercedes engine so you know it's going to be very reliable. And it's a 4 cylinder only 2.0 liters that is producing over 400hp. My guess is that weight will be the biggest problem? I believe it weighs 385 lbs. But given all of that power, the weight should be easily overcome so I suppose the real enemy will be CG?

Also, I'm no airplane engineer but how does one increase MTOW? Will extra power increase MTOW or is MTOW dictated by something else in the structure of the plane? Or will engine power increase MTOW slightly, up until you reach structural limits of the airframe?

So if engine power will increase MTOW then you don't have to worry about the extra weight of the engine, except for the CG, is that right? And then could you just add counter weights to rebalance the CG?

I do get this question fairly often. While I want to answer some of your questions I have had to work real hard since I started this thread from becoming a forum whereby people tell other why it won't work or can't work, or shouldn't be done. (Especially when many of them have no personal experience on the topic that would suggest their opinions should be taken seriously)

As anyone who has read this thread knows - I am not an engineer. I am just a private pilot who has embraced the idea of using an alternative engine in and experimental airframe, I have followed the auto conversion aspect closely since 1980 when I got my Private ticket.

The main challenges when adapting an alternative engine in to an experimental airframe are: This is loosely listed in order of degree of challenge.

1) PSRU - Gear box. There are few manufacturers out there and fewer who have a lot of time on their units. If you cannot fine one that will serve your application well then you have a very steep mountain to climb. I use the Viking Aircraft Engines PSRU (but not their engine). It may or may not work with other engines.

2) Weight. Many auto conversions end up being too heavy. This is something that you need look in to very carefully.

3) Ignition and injection/Carburetor. Needless to say this is very significant and it is getting very unlikely you can use an automotive OEM system for an airplane application. There are many aftermarket injection/ignition systems that work well, but they are not compatible with all engines. I use WWW.SDSEFI.com and it is excellent.

4) Cooling. Adding a radiator and cooling system can be quite the challenge.

5) Time. It will take more time to adapt an auto engine on to an experimental airframe than say a lycoming.

6) Personality. To do this you have to have a intense desire to see it through. You have to have an above average knowledge of piston engines. I personally had as much drive to see the auto conversion becomeing functional as I did to see the airframe completed. For me the engine conversion has been the most enjoyable part of this project.

7) An incredibly supportive family. I cannot imagine doing this while trying to raise kids. No way. I have a very supportive wife, and no kids.

It can be done, but it is not for the faint of heart.

If others want to comment about this, please share if you personally have any experience with auto conversions. I would appreciate this and to me it is more meaningful than folks who are just expressing 2nd or 3rd hand information.

Good flying to all.
 
Charlie, I hope my post wasn?t taken to be a negative jab at what you are doing. I commend you and others like you who are trying something different, and I hope you enjoy the journey down the road that you are taking. I was only commenting to maybe help educate the other guy that doing an auto conversion isn?t as easy as ?dropping it in?. While I haven?t tried to adapt an auto engine into an aircraft, I worked as a machinist and engine builder for over 10 years, and I have yet to see a car engine that I would use in an aircraft. Aero engines are way beefier for their hp levels than a car engine is. I would love for there to be a viable alternative engine to deliver the power, weight, reliability and beat the cost of a Lycoming, but I have yet to see one that comes close.
 
Please someone prove me wrong and show me a successful plane with an auto conversion. If they were so wonderful, there would be a lot of them out there. There is so much more to an engine than water cooling, and prob reduction drives. Car engines don’t have the surface area on the rod bearings, or the beefiness in the crank and rods that aircraft engines do. Aircraft engines and their crank, rods and bearings are tremendously oversized for their hp load..low surface speeds on the bearings, wide crank journals, all add to their reliability. This isn’t meant to poopoo on the original poster and his project.. I support others experimenting with.. well, experimental aviation. I think it’s great that he’s doing something out of the box and having fun and learning from it. I was just addressing the guy who thought it may seem simple..

You are wrong on so many levels here about engine design and this topic has been discussed at length here on VAF. Perhaps you can look here: http://www.vansairforce.com/community/showthread.php?t=154193, page 4, post #34 to see an airplane which has been flying over 20 years now, trouncing Lyconentals in multiple SARL races using Subaru power for many years. There are many other examples.

If you aren't involved in auto conversions, you are probably not aware of the hundreds of successful auto powered aircraft flying around the world. I've been involved with dozens of them supplying EFI and consulting on systems. I've flown one myself for 17 years.

Charlie stated that he didn't want this to turn into a debate at the outset of this thread. Let's sit back and see how this all works out.
 
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Tom.

Truthfully (to a degree) I violated my own request by venturing off of the focus of this thread, which is to highlight my experiences with this particular engine and airframe. My apologies.

Ross is right that if anyone wants to debate or speculate on auto conversions there are many other threads that this can and have been discussed in detail.

So please take those thoughts and share them freely on another thread.


UPDATE:


As far as my project goes, if all goes well I plan to move the project to the airport a week from today. I really do wish I had it farther along before the move but on top of this project we are also putting our house on the market to sell and we have to clean up the shop. (Probably more than folks want to know).

I also have received about 12 hours of dual in an RV6A in the past 2 weeks which is great, but not when it comes to getting my plane flying.

I suspect there will be a 2 to 4 week window of time where my time is obligated on other tasks besides plane building.

So no fear that the project as stalled due to project related issues. Life just happens. I will share all good or not-so-good news as things progress.

Charlie
 
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I?m reading the latest comments and following this thread with great interest. Wishing Charlie the very best...

I take exception to a comment ?Aircraft engines and their crank, rods and bearings are tremendously oversized for their hp load..low surface speeds on the bearings, wide crank journals, all add to their reliability?.

In my opinion aircraft engines are designed very light and must be spoon-feed very carefully to maintain reliability. Highly-leaded fuel must be used to prevent detonation. Likewise, very conservative ignition timing is used to limit pre-ignition / knock. Aircraft engines develop case and cylinder head cracks with regularity. Air-cooled cylinders don?t stay round and shock-cooling is the enemy. Acceptable oil consumption is something like 1 qrt/4 hours. Fill engine to full mark and it blows oil overboard.

Just adding my two cents?
 
I?m reading the latest comments and following this thread with great interest. Wishing Charlie the very best...

I take exception to a comment ?Aircraft engines and their crank, rods and bearings are tremendously oversized for their hp load..low surface speeds on the bearings, wide crank journals, all add to their reliability?.

In my opinion aircraft engines are designed very light and must be spoon-feed very carefully to maintain reliability. Highly-leaded fuel must be used to prevent detonation. Likewise, very conservative ignition timing is used to limit pre-ignition / knock. Aircraft engines develop case and cylinder head cracks with regularity. Air-cooled cylinders don?t stay round and shock-cooling is the enemy. Acceptable oil consumption is something like 1 qrt/4 hours. Fill engine to full mark and it blows oil overboard.

Just adding my two cents?

Jim,

I appreciate your and others support for my project but I do want to be clear that I hope to avoid mission creep/hijack of this thread to turn in to the never ending debate on alternative/auto vs common aircraft engines.

I am opened minded about my project and have been and will be very clear about the successes and setbacks of my project. I believe I have a viable plan. But since it is not flying yet, and I have not done a total W+B it is too early to call it a success or not yet. But all indications so far is that things look real good to me and I certainly look forward to the future.
 
The BIG move

A little over a week ago we made the BIG move to the airport. I had contemplated doing this a lot of different ways and ulitmately decided to hire a flatbed tow truck as you will see in the photos.

It turned out to be a real smart move. The width of the landing gear fit perfecdtly inside the rails of the bed of the truck. Plus, the owner operator was a real professional who had just the perfect gear to snug it down very securly for the 50 minute trip.

oNY.jpg


Here is another view that my wife took as we followed the truck up I-5. It was actually quite uneventful - thankfully!
oNl.jpg


I think I previously reported a heck of a time finding a hangar to rent. I finally found a 1/2 share of a 45' x 45' hangar at KTDO. It really turned out to be a super way to go and I am very thankful to have it.

oNr.jpg


Also, one point worth noting is that I struggled with the best idea on how to attach the lines from the tow truck to pull the plane up on the deck. I ended up using swimming pool noodle foam (that I bought at the aviation section at a local walmart) and cut them lengthwise and secured them above and below where I tied a 1/2 poly line that the tow truck could attach to. This proved as an excellent method. The foam kept the attachment from sliding up or down the gear leg and kept the line low enough so that it did not interfere with the cowl. I did not have anything attach to the nose gear. It went on great with zero difficulties.

oNw.jpg


There will be many trips to bring all the rest of the pieces and parts and tools to put this puzzle back together.

I have also had quiet a bit of flight instruction in two RV6A lately so things are getting done.

Charlie
 
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Good progress. I remember the days bringing my 6A and -10 from the shop to the airport. Always a bit worrying something would go wrong but both turned out ok.

Big step forward!

Thanks for the progress report.:)
 
Yes. Now if I just didn't have to spend a ton of time on our home getting it ready for sale I could actually work on the plane! I only mention that to explain why I have not posted much in the way of progress reports in the past few weeks. But I am hopeful that house will sell soon, and I can get the plane back together again....
 
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Jim, I know it looks like that but it's just where some of the fins are slightly bent. The light must have been just right to reflect so it makes them stand out. No worries (or bugs) at all. I'll tweak them before the shroud goes back on.
 
W+B done 1036lbs 71"

We did the Weight and Balance today. It was - mostly - good news.

I came in at 1036 lbs with a C.G. at 71.4".

Considering I am in uncharted waters with a never-before-tried engine, PSRU, Enging mount, liquid cooling system, etc, etc. I am happy with the numbers. If anything, the engine is too light!

For those of you who are RV6A guys, you will see the C.G. is a bit on the "AFT" side of the world. I did a full weight work up and I am still "in the box" at 76" but real close to the aft limit which is 77". With very low fuel, and 60 lbs in the baggage area I am at 76.4". I was a bit concerned that the cowling I made was on the heavy side, but now I am glad I did not make it any lighter. Of course there are a few creative things I could do to move the C.G. forward but at this point. It is good.

*** Updated. The full weight configuration was configured in the worse case scenario, certainly not what it will be during phaseI. Configuration during phaseI puts the C.G. at 73.2" which is very good. I add this because someone has thought I would be at 76.4 during Phase I which of course that will not happen....Just for clarification).

On a side note, I am 12 lbs heavier on the right tire than the left. I am sure this is for two reasons. The turbo is on the right, and the panel is heavier on the passenger side. Considering if I fly solo and/or that my wife is lighter than me, it is actually a "good thing" that the right was the "heavy" side and not the left.

So for now I am good with it. It is not "ideal" but it is good.

Also, is anyone else having problems accessing the Halie photo hosting site? I cannot access it anymore. It just is a blank website. No error, just blank screen.
 
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House move must be progressing well with restart on airplane project.

Good to see COG in acceptable limit. Airplane design / modification is an art form with tradeoff's affecting everything.

I'm following this project with keen interest...

Halie not working for me either - blank white page. I use Postimage to insert photos in VAF.
 
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Pretty darn light. Congrats on that. You're the lightest auto powered RV I've heard of.

Light planes fly nicer and perform better.

Looking forward to seeing how it all works and performs.:)
 
W+B clarification

I added some more info on the W+B post but since some folks may not go back to read it Ill add the info on a new post so there is a better understanding about the "full picture" of my set up.

The full weight configuration listed in the first post was configured in the worse case scenario, *(full weight, low fuel, full baggage, etc). certainly not what it will be during phase I. Configuration during phase I puts the C.G. at 73.2" which is very good.

At 1036lb I could easily improve the CG by adding some weight up front in the engine bay or move the batteries forward, etc. and I would still be fine on Total weight.

I cant say I feel the need to do this, certainly not now, but it is something to consider for the future.

If anyone every considers doing this set up. I just would have moved the radiator forward about 6" - 10". and may be even have a longer engine mount an inch or two. Minor, but worth the thought.....
 
... I just would have moved the radiator forward about 6" - 10". and may be even have a longer engine mount an inch or two. Minor, but worth the thought.....

I think that moving batteries closer to firewall would be first step. You'll save some weight from the shorter cables. Extending engine mount will add weight.

Finn
 
I think that moving batteries closer to firewall would be first step. You'll save some weight from the shorter cables. Extending engine mount will add weight.

Finn
I

With an empty weight of 1036 and arm of 71.3" I am in good shape with W+B.

I have two small LiFePo4 batteries. One on the fore and one on the aft side of the firewall. No meaningful gain in moving the aft one to the other side of the FW.

But thanks for the consideration.
 
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Filling the coolant.

As I continue to get the plane back together after moving to the airport, one of the unique aspects is to properly fill the coolant system.

Every liquid cooling engine system is different and I have learned how essential it is to get all the air out of the system.

For this set up I have learned that it works best to disconnect the large hoses (cool side and hot side) disconnected up near the Cyl head. Once those are full then I attach them and leave two ports open on the head. One was where the original OEM temp sensor was and the other was a small line that went over to the TB.

I am going to try to attach a picture here using a new method since HALIE seems to no longer bee working.


and......

Coolant-Fill-system-pic-color-coded-450px.jpg


(the embedded image was done using postimages.org - do not confuse with postimage.com)

There are 3 colored circles and an violet colored lines. Here is what those represent.

Yellow. This is where the OEM temp sensor was. Notice the extension on the port. This is only attached when filling. Once the air is burped out, I cap it off.
Green. This is where the coolant line for the TB was. I also cap this off when done filling the syste.
Violet. This is the aftermarket catch can that "catches" any bubbles left over. Notice the reinforced silicone line that goes from the thermostat housing over to the catch can.
 
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Filed for Air Worthiness inspection

I have applied for the Air Worthiness Inspection.

I have been working very hard on putting it all back together and doing a lot of finish work that just could not be done before the control systems were installed for the last time. Mainly routing the stick grip wiring antenna wires, ELT wires, etc through the spar. It has been a lot of tedious work but so far I think it has gone well. I will feel much relieved when the panel is back in and the engine is making heat again.

I will keep the updates coming.
 
regarding the cooling filling, I recently purchased and used one of these vacuum fill setups. it's supposed to solve any trapped airbubbles problem:


https://www.amazon.com/UView-550000...e+Tool+Kit&qid=1596726370&s=automotive&sr=1-1

It seemed to work really well, and fast to fill the system. I haven't done a test flight yet (maybe I'll get to fly today).

Here is a guy using the same one on a truck:
https://www.youtube.com/watch?v=eMvalUMNyYU

Jeff, Good to hear from you and thank you for the tip. I have not had any issues once I switched to the method I described, but I am always looking for better ways to get the job done...
 
I installed the panel yesterday. So far everything seems to be working properly. I was made much more challenging because in a moment of self indulgence I purchased two grips from Infinity. They are very very nice and very very complex. It added a ton of time wiring the switches to the grip like 2 axis trim, PTT, Flaps. etc.

My next venture is to reinstall the rudder pedals. I took them out to give me more room to work on the wiring.

Then on to bleeding the brakes for the first time. I have bled brakes on cars for years. But I have not used the "pressure up" method. But it seems to make sense. I have Cleveland 40-78B wheels and 30-9 brakes.

I am leaning on trying the pressure up method.

If anyone has any experience on this, please share.

Thanks
 
My wife has joined me in wrenching on the plane, every day for 2 weeks to get this ready for the airworthiness inspection. She's an absolute gem.

It is tedious but we are making good progress.

One thing that stands out to be is how "sqatty" it is. Quite tail low. I put a 1.5" thick board under both tires and it is still quite squatty. I have always known the -6 still low compared to the -9 an -7 and I don't like it.

It makes for poor visibility. on landings. Larger diameter tires would help in several ways. 1) More stability, wider tires, stronger tires. 2) Better visability over the nose. 3) better larger brakes. Tires are actually cheaper too. The down sides are reduced speed, and some added weight. I care more about better visibility and stronger breaking and stronger tires than I do the reduced speed and increased weight. So I am 98% sure I am going up to 6.00x6 tires on the mains. I know this is unusual for a -6a. But the -6 guys do it all the time. I set it up this way and put a level on the longerons and it takes me from 5.2 degrees tail low up to only 3.7 degrees tail low with a 1.6" lift that I expect I would get with 6.00x6 tires.

Just food for thought....

Oh....I dont plant to run with pants. Seems like more hassle than the speed gains you get that are not that important to me anyways....
 
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TLAR Engineering Ground Attitude

My wife has joined me in wrenching on the plane, every day for 2 weeks to get this ready for the airworthiness inspection. She's an absolute gem.

It is tedious but we are making good progress.

One thing that stands out to be is how "sqatty" it is. Quite tail low. I put a 1.5" thick board under both tires and it is still quite squatty. I have always known the -6 still low compared to the -9 an -7 and I don't like it.

It makes for poor visibility. on landings. Larger diameter tires would help in several ways. 1) More stability, wider tires, stronger tires. 2) Better visability over the nose. 3) better larger brakes. Tires are actually cheaper too. The down sides are reduced speed, and some added weight. I care more about better visibility and stronger breaking and stronger tires than I do the reduced speed and increased weight. So I am 98% sure I am going up to 6.00x6 tires on the mains. I know this is unusual for a -6a. But the -6 guys do it all the time. I set it up this way and put a level on the longerons and it takes me from 5.2 degrees tail low up to only 3.7 degrees tail low with a 1.6" lift that I expect I would get with 6.00x6 tires.

Just food for thought....

Oh....I dont plant to run with pants. Seems like more hassle than the speed gains you get that are not that important to me anyways....


Before just doing some TLAR re-engineering of your aircraft's ground attitude and landing gear, you need to consider the potential impacts that this may have on the takeoff and landing performance as well as the impacts on the performance of the nose gear. I'm pretty sure that Van's designed the ground attitude of the -A models with a reason...

Skylor
 
Skylor

Yes I have considered that and done some home work on it.

Having looked Vans aircrafts for decades I often wondered why some (especially 6A's) sit noticeably more tail low than others. While there are certainly many reasons for this, I suspect part of the reason that mine might sit lower than others is that my engine is light and the weight on the nose is a bit lighter than others. It would be fascinating to get real world numbers of static angle of attack on say a dozen -6A to see how similar, or not, that they are.

I have talked with a guy who has worked at vans for many decades about this and some of the reasons the other -6A models sit tail low compared to the -7A, 9A, etc.

I do hope though this does not cause thread drift on the virtues, or not, of different size tires on Vans models. Not that it is not a valid topic, it is just not the purpose of this thread.
 
fuel flow testing

This past few days has been a lot of under the panel work. What could be more fun that lying across the wing spar upside down in 90 degree heat looking at wires behind the panel and bleeding the brake system!

The other task was doing a fuel flow check. My wonderful wife helped me test the fuel flow with the plane at the extreme climb attitude as well as on the ground. This was done testing the Walbro (USA made) in line pumps. One at a time of course, with the left tank and right tank. It took several hours.

Results: Single pump. 42 gal/hr. Both pumps. 66 gal/hr.

There was no change in delivery volume at static vs max climb attitude.

I did have a real challenge bleeding the brakes. Not because of a leak, but oddly enough, because air was being sucked in to a line upon release of the application of pressure. I after hours of testing and cussing, I traced it down to one of those compression fittings. I will post more on this with photos that show some lesson learned on the type of compression fitting to use, and the ones NOT to use. IMHO.
 

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Update: progressing well

Just wanted to say that things have progressed well over the past 2 weeks.

I am in the final stages of prep for the air worthiness inspection. There are a ton of "little things" to take care of. Cotter pins, torque values on important nuts, torque seal, spiral wrap on wire looms, securing hing pins on control surfaces, etc.

I have the EAA prep docs and flight card check lists and they are quite helpful.

The engine is running well, other than one pesky small oil leak on the oil pressure sender.

I also have two very small air bubbles in the cross over brake lines. The brakes are quite firm but I do want to get rid of those. I have a considerable loop in the lines that cross over between the left and right side and its no surprise that the air wants to stay put in the top of those lines. I am using a 12v diaphragm pump which works quite slick to pressure feed the brake fluid upwards through the system.

Who knows, I may be airborne in a few weeks.....but no promises. I am sure Murphy will visit here and there.....
 
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Air Worthiness Certificate: PASSED

To those who have been patiently following, I received my Air Worthiness Certificate today. I am very happy about that.

The inspector, Charlie Cotton from near Puyallup Washington came down and spent several hours looking over the paperwork and the plane. He was very thorough and asked a lot of questions and made several suggestions. He found two issues that needed addressed but they were easily fixed on the spot.

Sandi also took a very short video of my first taxi test. You can find it here.

https://youtu.be/LrTd6YI5WMM

The next step is that I need to trouble shoot some odd readings on my ammeter. I have dual batteries that are separated with two contactors. With one of the battery on line it is charging 30amps.....It usually charges at less than 5 amps. When I bring the second batter on line it jumps to 50amps!!!

I had the alternator tested and the local shop said it runs fine. UGH! This is an OEM Honda Alternator with the ELD/LIM system. It is basically a one wire alternator. If anyone has indepth knowledge (beyond google) about the ELD/LIN regulators please PM me.

I know some may suggest to swap out to an external regulaotor but I am VERY reluctant to tackle modification of the new mounting system it would take to make this happen. The custom mount I am using now was a very time consuming effort. I am not using the OEM alternator mount and I needed that space to make the turbo mount.
 

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Battery charging amps

If your batteries are pretty low you will see high amps initially and then as the levels get higher the charging amps will drop. Are the batteries fully charged?

Is your ammeter measuring the total amps being used by the system or only the amps going into / coming out of the batteries?
 
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If your batteries are pretty low you will see high amps initially and then as the levels get higher the charging amps will drop. Are the batteries fully charged?

Is your ammeter measuring the total amps being used by the system or only the amps going into / coming out of the batteries?

They are low, one at 13.0 one at 13.1. But they have been that low before and I have never seen any amp numbers even close to that before. Never even up to 10 amps, let alone 50.

But, just to make sure, I am going to charge the batteries up full and reinstall the ALT and check it again.

The ammeter measures the output off the B (heavy) wire from the Alternator.
 
Voltage

If the output of your alternator is below 15 volts, there’s nothing wrong with it. The current draw is a function of the batteries and other electronics.


-Andy
 
If the output of your alternator is below 15 volts, there’s nothing wrong with it. The current draw is a function of the batteries and other electronics.


-Andy

I am beginning to believe (and hope) that is the case as well. The only thing that makes me wonder is that I have never seen anything close to that charging rate when the batteries have been low before. But lets hope it is that simple. (If that is the case then the charging rate must be exponential as it relates to the state of charge of the battery and this must be difficult to tell if all you have is a voltage value). Learning all the time!

I hope to get back out to the airport to get the alternator back on and the batteries charged back up to full strength soon.

Thank you.
 
Alternator is good.

Well, good new on the alternator, it was fine. I after starting the engine I checked and the voltage was within range (I think it was 14.6 or close to it). So I let it run. Andy was right. Turns out the batteries were drained more than I would have thought 13.1v would have indicated. The trickle charger just did not bring it up to full charge. A good lesson for me on what to expect out of my ammeter.

I was able to get out on the runway today to get up enough speed to condition the brakes. They hold much better now.

Next up: A new gremlin in the headsets and more finish work to do on the radiator scoop.
 
Well, good new on the alternator, it was fine. I after starting the engine I checked and the voltage was within range (I think it was 14.6 or close to it). So I let it run. Andy was right. Turns out the batteries were drained more than I would have thought 13.1v would have indicated. The trickle charger just did not bring it up to full charge. A good lesson for me on what to expect out of my ammeter.

I was able to get out on the runway today to get up enough speed to condition the brakes. They hold much better now.

Next up: A new gremlin in the headsets and more finish work to do on the radiator scoop.

Way to go Charlie!! Impressive progress, it seems superhuman to me. I'm looking forward to good flight data. Fly safe!
 
Thanks Bill,

I actually had to pull the panel out because of the intercom/radio issue. Fortunately I had the panel wired with 6 cannon plugs so it "only" took me 2 hours to remove. (Hate the canopy release handle!).

Fortunately another friendly hangar neighbor let me slide in his radio in my tray. Same results. So I know its not the radio. Probably the intercom or wiring to the intercom.

I wired up the radio directly (not through the 403mc intercom and the radio works great.

So the intercom goes back to the factory for testing, that way I can learn if its the intercom or some unforseen wiring issue. Nineteen wires going to and from the intercom/radio/antennas/power/ground. ugh.

Of course I don't need an intercom for phase 1 but I hate the thought of putting that panel back without a function intercom.

But one way or another this is going to get fixed!
 
100,000 views - DANG!

In case some of you may not have seen it this topic/thread just passed over the 100,000 views mark.

WOW.

There is keen interest interest in the viability of using auto engine with a good track record in an RV. While I certainly am optimistic, I have to say - lets wait - before opening the bottles and celebrating. While all the major components are proven. Its the conglomerate of them that needs to wait to get a passing grade - or not. (But for me I have to confess, I have bought the bottles...)

I do not see anything that suggests in that this is not a viable powerplant concept.

Thanks to all who have provided valuable assistance, including those who have provided respectful helpful critique.

I will keep you posted.
 
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My honda fit has 300,000 km on it and runs perfectly, never let me down. There is no doubt it is a great engine. Like every automotive installation in an airplane the devil is in the details. Every builder does it differently. And little details have become big problems very often in these types of installations.

I would say you should plan to have an engine out in your first 50 hrs. Depending on where you fly and how confident a pilot you are, that might be manageable. Like if your airport has 5000 ft of pavement and you can do your testing 3 or 4000 ft above it. But if you have a 2000 ft strip surrounded by built industrial area and it is always really busy... hmmmmm. Lots of practise of forced approaches... Planning for that scenario just makes sense based on past history of auto conversions of all types. You might not have any problem, but prep and planning is how you manage the increased risk. That’s how the pros do it.

I hope you are very successful.
 
My honda fit has 300,000 km on it and runs perfectly, never let me down. There is no doubt it is a great engine. Like every automotive installation in an airplane the devil is in the details. Every builder does it differently. And little details have become big problems very often in these types of installations.

I would say you should plan to have an engine out in your first 50 hrs. Depending on where you fly and how confident a pilot you are, that might be manageable. Like if your airport has 5000 ft of pavement and you can do your testing 3 or 4000 ft above it. But if you have a 2000 ft strip surrounded by built industrial area and it is always really busy... hmmmmm. Lots of practise of forced approaches... Planning for that scenario just makes sense based on past history of auto conversions of all types. You might not have any problem, but prep and planning is how you manage the increased risk. That’s how the pros do it.

I hope you are very successful.

Scott,

My plans exactly. I am very fortunate I am based at KTDO which has almost 4500ft and is rarely busy.
 
Update

I got great service from Flightcom. They sent me a replacement super quick and I am back in business. (I am not sure what was wrong, but things work well now.)

I am installing the empennage fairing and doing some finish work on the radiator belly scoop and other minor things.

In short, things are progressing well. Not as fast as I would like but things are going well.
 
Yes mechanical things do break for no reason, my first landing in suby powered
RV 4 was dead stick as crankshaft broke 1400’ above airport, exciting but no
Problem ! 2nd engine never even hicuped !
 
Yes mechanical things do break for no reason, my first landing in suby powered
RV 4 was dead stick as crankshaft broke 1400’ above airport, exciting but no
Problem ! 2nd engine never even hicuped !

Tom,

Good to hear from you. Yes, my plan is to be within glide range of an airport during the 40 hour phase 1. Not because I have undue concern, but it is just smart practice, and it should be fairly easy to do with 3 airports close to each other in this relatively low activity airspace. Not to mention I-5 goes right through the middle of my phase I area. But I really want to avoid making "breaking news" on any given night....

I will be very interested in the cooling ability of this radiator scoop design. It is not near as fancy as Ross'. It does not separate the intake from the fuse (which is ideal) aerodynamically. It also does not have a mechanical flap on the outlet portion of the scoop which is also ideal. I took the K.I.S.S. approach. If I need to modify it I will.
 
Scott,

My plans exactly. I am very fortunate I am based at KTDO which has almost 4500ft and is rarely busy.

Flight test risk management is all about prep. Sounds like you are being meticulous. On my 4 I have a rebuild engine so I have to do my breakin in the air, which I don’t like. At least you can ground run as much as you want and can continue tweaking until everything is perfect. I can do a couple of full power runs before I overheat, or lower power runs before I glaze the jugs. Then I just have to go and cross my fingers, assuming all my pressures and temps are good of course.

Look forward to reports.
 
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