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RV9 200HP Yamaha Sidewinder

Several years ago in a conversation with Craig at OSH he mentioned a constant speed project he was working on. Perhaps yours might be a good test bed for such testing if he is still pursuing that avenue.
 
Great news on the propeller front. Craig Catto is working on blades for my Airmaster hub so I can replace the sensenich blades. After some calculations Craig says that I should be at 174KTAS, 14kft at my current cruise of 8GPH and 120hp as calculated from the ECU.
 
Great news on the propeller front. Craig Catto is working on blades for my Airmaster hub so I can replace the sensenich blades. After some calculations Craig says that I should be at 174KTAS, 14kft at my current cruise of 8GPH and 120hp as calculated from the ECU.

Very nice. With a Vne of 182 KTAS on the 9/9A, this is about as far as I would care to take it - and I would probably prefer to be a couple thousand feet higher doing it to ensure smooth air.
 
Great news on the propeller front. Craig Catto is working on blades for my Airmaster hub so I can replace the sensenich blades. After some calculations Craig says that I should be at 174KTAS, 14kft at my current cruise of 8GPH and 120hp as calculated from the ECU.

@Teal Any updates on your set up!? Long term looking to do the 3 CYL turbo Yamaha on a Mustang II /RV14
 
I am currently at 170 hours and I have been really loving this set up with the exception of not having the correct blades for high altitude flight. I did have an in flight emergency lately. The water pump broke sending the coolant temp instantly soaring. I went to idle and set up for best glide and the engine cooled to just hot but not over heated. I was able to glide to an airport thankfully. I had replaced the water pump only 2 hours before this with a aftermarket unit that was supposed to be better than the OEM which uses a poly impeller. The shaft broke in in half on this unit. I have since replaced the pump with the stock unit but have designed a new water impeller and shaft taking into account MMOI and fluids dynamics. I will be testing at least 4 different impeller design on the test stand. I hav also installed a variable speed electric water pump that is PWM controlled. Currenty I do not have the ECU controlling the electric pump as I want to control it while testing coolant temps and pressures through out the system at different flow rates. I may eventually turn control over to the ECU and add a table in the ECU base map to adjust speed based on the coolant temp. My goal is to build a better mechanical water pump and use this electric for ground use during taxi or after shutdown to continue to cool turbo down as it is water cooled. No progress on the propeller blades. Not sure at this time if CATTO is going to make them. It has been slow going there.
 
Oh, yeah, MMOI. I was thinking the same thing myself.......🙄 😳 😂

My hat is off to you, and everyone on the forum who is keeping the word Experimental in EAA, especially when you use science and engineering to do it. I am humbled.

OK, so I "Googled" MMOI. 3 hits:

1. Matière Molle aux Interfaces (French: Soft Matter with Interfaces)
2. Multi-Mode Optical Isolation
3. Mass Moment of Inertia (physics)

So, help me out, if you wouldn't mind. Always looking to learn something new!
 
Awesome Teal and thanks for the update!!!

When my LYC gives out I am planning on copying your setup for my Mustang II getting into the 200-250hp turbo with an electric constant-speed propeller and its laminar wing would make this plane scream.

Cheer and can't wait to hear more about it
 
Good news on the Propeller blades. Craig Catto has the new blades modeled up and mold will be finished in a couple weeks.
 
Craig Catto has the first blade from the Mold!! Currently have 223 flight hours. Recently I have been recording a bunch of numbers to give a good comparison between props.
Today I recorded numbers at 10kft, 14kft and 16kft. Numbers are in true airspeed. The order is MPHT, alt, fuel flow, AFR, ECU calculated HP. these are more eco cruise numbers. it is interesting to note that I can still make 180hp at 16kft. Also important to note that I do not maintain this power in level flight as it will easily exceed the VNE. I obey the True air speed VNE of the RV9 and am very cautious of this at High altitude where true airspeed numbers can creep up fast. From some of the Data we have determined that the blades are stalled from adding so much pitch as I go up in altitude so these new blades should give great improvements at altitude.
155MPHT, 10Kft, 5.0GPH, 13.5AFR, 66HP
177MPHT, 10Kft, 8.1GPH, 13.3AFR, 106HP
158MPHT, 14kft, 5.3GPH, 13.5AFR, 75HP
190MPHT, 14kft, 8.2GPH, 13.3AFR, 109HP
166MPHT, 16kft, 5.5GPH, 13.4AFR, 78HP
180MPHT, 16kft, 7.1GPH, 13.3AFR, 98HP
192MPHT, 16Kft, 8.2GPH, 13.3AFR, 109HP
 
Teal,

Thanks for posting the numbers, impressive.

I'm getting more and more interested in yamaha conversions now that there is a good gearbox for them, but still have questions regarding the vibration/balance of a 3 cyl engine, as well as observed TBO times.

Are there rpm ranges to avoid with the 3cyl vs 4cyl? What vibration/harmonic testing was done?

Also, where is the best place to discover this information? If someone put 1000 hours on this engine, did a teardown and inspection, where would I go to find that information?

With lycoming everything is known, but with this new experimentation it all boils down to experience, so where/how is this experience collected?

thanks
schu
 
So far I have not discovered Any RPM's to avoid. Comparing to the Lycoming that came off this Plane runs smoother in all RPMs. Some of my passengers that have turbo prop time say that it reminds them of a turbine.
Unfortunately there is not a good place to discover the information you are requesting. Also the TBO time or in this case TBR is not yet even close to being determined. For me I use 500 hours as a basis of if it would be worth it. I am pretty sure it will be well beyond that but as an investment thats what I used. I brand new long block is about $6000. I am currently at 230 hours. I would consider this very early stages of a track record for these engines in aircraft use. Thats one of the big reasons most are sitting on the sidelines and not jumping in. I am an experimenter at heart and love the challenge and potential reward to be gained is why I jumped in.
 
TBO...

Teal: Would be interested to tear it down at 500 hrs. and check out where it's at...with in service limits, etc. Tracy Crook did that years ago after hitting 800 hrs. on his Rotary Mazda 13B, and was happy to discover it was still well within service limits and should have been able to easily reach a 2000 TBO.

Doug

RV-3A restored and sold
RV-9A Mazda 13B/FWF
 
Teal: Would be interested to tear it down at 500 hrs. and check out where it's at...with in service limits, etc. Tracy Crook did that years ago after hitting 800 hrs. on his Rotary Mazda 13B, and was happy to discover it was still well within service limits and should have been able to easily reach a 2000 TBO.

Doug

RV-3A restored and sold
RV-9A Mazda 13B/FWF

I used to race 13Bs in cars with just overlap, port and polish, and we would work them hard. When others in the group had to overhaul the Toyota 22Rs we decided to do the same but found are engines still didn't need it.
 
Fortunately its the same base engine that Yamaha is using in their Side by sides. But that aside there is 1000's of used engines available for years to come.
 
Ron,
I am curious what software you used for propeller simulation and did you use this particular Sensenich blade profile?
 
Hi Teal,

Glad to hear that these Yamaha snowmobile engines or similar will be around for the future.
I saw a post here on VAF recently by an otherwise prolific builder who said he was hanging it up because it didn't make sense anymore due to the high prices of engines. Your efforts add hope to many for having viable alternatives.

I am curious what software you used for propeller simulation and did you use this particular Sensenich blade profile?

I have been dabbling with design for a very long time. For propellers, I have used the freebee Javaprop. It can give reliable results with good data input, but the learning curve requires some dedication and everything is metric. I duplicated a similar prop in a more limited but easier program, PropDesign and the results were close.

No, I did not have any specifics on the Sensenich blade other than the posted 67 inch diameter, 3 blades, estimated cord and your posted flight data. That is enough to get pretty close to what the prop is actually doing. Those factors also give a hard upper bound to prop performance.

The results show efficiency is fairly good at cruise, pushing the blade loading a little with a lift coefficient of .8 at cruise and maybe a lot at higher horsepowers, though . As others on this thread have suggested, increasing the diameter might help the most and be better all round. A few extra knots is always nice.

Ron
 
We have been recalibrating the fuel flow by making a flight and draining fuel to see how close display is. We were about 10 percent off all this time. I knew early on that it was a bit high but just left it since I would always have more in the tank than what the display said. Now that I am getting the new prop I want to make sure I have good numbers. Currently I can cruise at 150KTS (173MPHT) on 7 GPH if I run it on the rich side.(13.5 AFR) If I run it at 14 AFR it 6.5GPH. We also adjusted boost target to be as low as possible below 60% throttle in the cruise RPMS. This has lowered IAT's and makes turbo not work as hard. It so cool to be able to fine tune these engines for a particular application. I just made a flight of 300 miles, burnt 11.9 gallons precisely (drained tank and verified) averaged 150KTS in cruise and climbed up and down a lot through 15kft a few times. Thats averaging 25MPG!!
 
Currently I can't load the engine much above about 13kft even with prop set on full pitch. So I am hoping these larger Blades by Catto will allow me to load the engine more at the lower RPM's. I'm being told that it will help climb performance to but I can't imagine it better than it all ready is. I can maintain over 1500FPM from 15kft to 17Kft.
 
He posted on another social media platform yesterday, made a fine landing and walked away. Has not examined the FWF yet but speculates it was an exhaust leak.
 
Bummer. That's scary. I wonder what caused the fire.
I hope Teal is ok

Very glad he's ok. This is his account of what happened:

"I just wanted to be the first to tell you guys I had an in flight emergency today. The cockpit filled with smoke and it appeared the cowl was on fire. The engine was still running so I flew for a couple miles to get close to a road then secured the fuel and shut it off. Uneventful landing on a paved road with no cars around. There were flames coming out of the cowl vents so I covered every cowl opening and was able to put it out but not before it burnt the front up pretty good. More detailed investigating will unveil more but initial thoughts are possible exhaust leak either at turbo or crossover pipe. Shroud your exhaust really good!!"

HIS UPDATE :

"I believe that we found the cause of my inflight fire. One of the fuel rail fasteners had backed out and allowed one side of the fuel rail to lift of the #1 fuel injector causing a fuel leak or possibly a spray. I am very disgusted and disappointed in myself that I did not either safety wire or thread lock those two fasteners but at this point the best I can do is warn others. This was one of the Skytrax designed fuel rails made of aluminum instead of the stock plastic. I am certain that it was not the fuel rails fault but the stock rail uses a flange head bolt with a soft polymer washer and I used a socket head cap screw with no washer. This may or may not have contributed to the fastener to loosening. At this point I would suggest either thread locker or safety wire on these fasteners. See the attached picture for the gap between the fuel rail and mounting spacer as well as the fastener head gap. For those that asked...the fire was put out by placing anything I could find in every cowl opening to starve it of air. This included my jacket, a towel and some rags I had in the back and every item I could get off bystanders."
 

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Ouch. That looks like pretty much a write-off of everything FWF, and maybe the firewall too.
 
I am relieved yet very disgusted with myself that I did not safety wire the bolts that held the fuel injector rail to the injectors. I also got used to flying it and not opening the cowl every 10 or so hours. I could have caught this bolt coming loose on a quick inspection. I was approaching 300hours on this engine in flight and absolutely loved everything about it. Very Sad that another conversation engine goes down for such a silly mistake.... I will have another one of these engines flying in something at some point.
 
Shows the inherent risk when experimenting with something outside the normal engines.

It's good to know that your on the ground in one piece and able to rebuild and fly again another day.

I really liked your Yamaha project and thought that would be an excellant upgrade for my 9 as most of my flying is out west over the rocks. And 1500 fpm at 15,000 ft:D oh ya baby I can hardly wait.

Looking forward in following you in your repairs and flights in the future.

Tim
 
Teal- If I might comment. It's easy to kick yourself when something like this happens, and yeah, it sucks. But it seems to me that you learned something very valuable from the incident, and a lot of other equally valuable stuff prior to that.

I've spent my career in aerospace, starting as a flight line mechanic in the experimental prototype hangar of one of the major Wichita manufacturers. In that environment, preflight and post flight inspections are about as stringent as humanly possible with calculations detailed engineering oversight and contingency planning in abundance for literally every flight, yet even with all that, I've seen lots of stuff broken in seemingly ridiculous ways.

You can't plan for every eventuality, but each and every event like this can teach something, whether it leads to a process change, a system redesign, or some other product improvement that gets us where we are.

You learned a bunch of stuff that will be foundational elements for next time, provided an honest evaluation of what went wrong as a cautionary tale to others who may come after, and most importantly, nobody got hurt.

Thanks.
 
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Shows the inherent risk when experimenting with something outside the normal engines.
To be fair, if the failure was caused by a lack of a safetied fastener, that failure could happen on any engine, Lycoming or automotive. What's unfortunate is that the naysayers will use this as one more data point justifying their put-downs of converted engines without looking further.

It's good to know that your on the ground in one piece and able to rebuild and fly again another day.
This, 100%. It looks like it's rebuildable from the photos we've seen.
 
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