Rans S21 Outbound build French Island. Nic and Mike. Start date 3rd May 2022. Finish date 1st February 2023. Target $ spend to be determined.

[facthunter]

I can't see how the mixture can be a significant factor but if it's lean there will be more roughness in the running and they are more sensitive to detonation. All engines have  critical RPMs you shouldn't run at. The crankshaft journal radii are critical in their formation (Machining) A scratch can be the beginning of a crack. That crank has narrow webs so the metal section is less. I think they have tried hard with the UL motors. Like the Jaburu the motor has 7 bearings on the sixes. I really wonder if the motor needs so many. It's not a diesel. Pontiac made a V8 and put in a lot of main bearings but didn't keep that feature long..  Nev

[Mike Gearon]

On 19/6/2023 at 9:15 PM, facthunter said:

I can't see how the mixture can be a significant factor but if it's lean there will be more roughness in the running and they are more sensitive to detonation. All engines have  critical RPMs you shouldn't run at. The crankshaft journal radii are critical in their formation (Machining) A scratch can be the beginning of a crack. That crank has narrow webs so the metal section is less. I think they have tried hard with the UL motors. Like the Jaburu the motor has 7 bearings on the sixes. I really wonder if the motor needs so many. It's not a diesel. Pontiac made a V8 and put in a lot of main bearings but didn't keep that feature long..  Nev

Thanks Facthunter. Apologies for not looking here sooner. I’ve been immersed (drowning) IFR.

 

I’m getting close to IFR checkride in USA and have recently travelled backward. 2 weeks ago I had “beautiful” and “perfect” as debrief on approaches. We added DME arc and circle to land and it’s all fallen apart. Instructors I’m learning can make a single comment and it can be a game changer. I’d reduced scan from top Center 6 pack and moving away and back from various instruments. I recently asked how many IFR students they train. Chief instructor said it’s the opposite… usually retiring from IFR at 65. Anyway, that’s why I haven’t been here. I’ll respond below to comments on engine.

 

That response is why I still visit rec flier. Depth of knowledge. Huge depth. Id also wondered why there are so many journals. In the engineering I’m familiar with we add a third bearing at our peril. It’s probably going to cause more trouble or expense and/ or assembly/ maintenance problems. I don’t imagine UL would be putting a crank down into the journals where they have to press or hammer it into place. I’ve never pulled apart any engine other than the single 2 strokes I used to race. Do crankshafts get tapped into place? That would indicate stresses that aren’t relieved. Or, stresses build and a crank shaft that did drop in is no longer exact after use. Indicated by no longer being drop in.

 

The engine in question did have temp problems on a number of cylinders. Why? I can only think that the bed in clearances were tight on particular cylinders. How could crankshaft alignment stress translate into cylinder temp problems. 

 

UL. Yes, they really do appear to be working at getting it right. My current opinion is that Nic and I require a brand new crankshaft that’s been appropriately strengthened as well as an explanation of what went wrong. Just an explanation of what went wrong probably isn’t going to be enough.

 

aircraft 1. We may assemble and test. We have a ground adjust Sensenich so we aren’t messing with the unproven airmaster on the UL520t. I think this will be the first such match of airmaster and the 520t. I’ve mentioned before I was on the phone a year ago with airmaster tech and at the time they said it wasn’t approved. 
 

maybe… we assemble and test and if the temps are doing similar things to the failed example we stop flying until a solution presents. I’m 8 weeks from return and would rather be the test pilot. I’m most responsible for the buying decision.

 

aircraft 2. At this time I’ll put the Titan in aircraft 2 or swap them so Nic has the Titan. It’s nice to have options.
 

For build 1 

 

 

[facthunter]

Please forgive me for not seeing this earlier. It's probably best if you and I contact each other off forum. Ian BAKER may do me a favour in that regard and pass on my details. Regards Nev

[Mike Gearon]

On 12/7/2023 at 9:33 PM, facthunter said:

Please forgive me for not seeing this earlier. It's probably best if you and I contact each other off forum. Ian BAKER may do me a favour in that regard and pass on my details. Regards Nev

That sounds great. I’d like to learn more in general on cranks etc before I meet people at Osh Kosh to discuss the failure.
 

I’d posted the above with an off topic IFR discussion. I thought that was why 🙂 I wish the edit function would stay open a little longer, I looked at that the next morning and would have deleted the paragraph.

 

Back to Rans S21 build……Engine looms large. If we’d had the Titan and I’d have painted the first S21 we really would have been flying Feb 2023.

 

Engine.. We finally shipped the UL520t FWF kit from Kaolin Aviation in Florida  2 days back. It’s been a long time promised. I’d even told Ray I’d bring cash to Osh Kosh in 2022 and now we roll around to Osh Kosh 2023. That being said I expect UL USA can now ship S21 FWF kits within a few months of order. That’s if anyone wants them. I’ll report in detail from Osh Kosh on what is what. Arriving there 24th for first day of show and hope to understand whatever is actually going on with that failed crank. 
 

Engine for aircraft 2. I’ll know more after Osh Kosh!
 

Paint..

 

Aircraft 1 as in pic below. Paul Chernikeeff (Rotec and Jabiru water cooled heads) is painting at Tyabb. All control surfaces done and working on wings and fuselage. Nic is going all white and will decal later is I think the plan.

 

Aircraft 2. I’ll continue painting when home early September. I didn’t want to stuff up Nic’s aircraft even though he would have trusted me to paint. I’m enjoying painting. Challenge is to avoid orange peel. Gun settings and speed and she’ll be right.

 

 

 

 

[Mike Gearon]

Day 3 at Oshkosh 2023. Spent time with the UL guys. It’s a different stand in a very good way since some staff shuffling. Herman Eshius is a UL dealer and well liked and respected member of the Experimental Aircraft community. I felt good talking with Herman. 6 years ago he did the ULPower engine workshop in Belgium and knows the engines inside out. I also spent time with Patrick. One of the UL factory owners.

 

Conclusion is that there have been 4 cylinder crankshaft breakages in the past. One example in USA was a prop strike where it was recommended that the crank be replaced. It wasn’t. It broke later. Other 4 cylinder breakages were attributed to metallurgical problems. A small number. 
 

The indications prior to NTSB releasing their findings is that the engine was in a low RPM state with the prop pitched full course at failure. There had been a very hard landing at some point prior to the failure. There was some mention of the waste gate on turbo I’d not quite understood. The airmaster prop is still listed on Airmaster site as suitable for the UL520is. I’m not sure at this point it is. I guess we wait on findings.

 

UL520t on Rans build 1.

 

We have decided to proceed with the UL520t install and fly with due care for the unexpected. The aircraft is fully wired up and ready for the engine to be mounted and painting finishes soon. I’ll be back on French Island early September and looking forward to participating in the first flights.

 

Titan 180hp on build 2.

 

Again, it was great being at Oshkosh and able to talk directly to the people that count. James Ball is in charge of the Titan engine at Continental. Nic and I were given the choice of waiting until first quarter or perhaps second 2024 for the engine with nitride coating or taking a steel barrel next month. James said if we start the engine once a month and use the correct oil the cylinders at seaside location will be fine.

 

He also explained that the coating is an in house process and the machinery is old and causing problems. I took this to mean we really could be way out on delivery time 2024 of the nitride coated engine.

 

So, I talked with Nic back in Oz then went around and ordered the Titan with steel from Jamie. I sent her a picture of a recent Titan delivery to a Rans S21. Ours will be colors as here.

 

 

 

 

[Mike Gearon]

I’d forgotten to mention a really important point. The bearing cup rotated. Apparently there is a small lip on each cup that prevent rotation. From what I’m told there must have been some forces involved in rotating this assembly.

 

I talked with one of the engine guys who had experience with Jabiru. He said Jab engines can get so out of alignment they won’t start until cooled down. The UL is of course based around a Jab engine. I was also told Jabiru bottom ends don’t give a lot of trouble. 

[Mike Gearon]

Heading toward time to return to Australia. Took the opportunity to fly from Lincoln down to Hays, Kansas Rans aircraft factory. A little hesitant with 3rd ever solo landing in the 1941 interstate and a direct cross wind of 17 g20kn along with a 1,000ft runway at Rans. Couldn’t find the factory and had to go with Google maps and follow the streets while paying attention to the various tall towers dotted around. Planted it 3 point and settled in. The next day Randy had good tips on taxi. The taxi to runway crosses a dam bank where the wind runs up the dam bank and can lift the wing. So, taxi with aircraft down the bank a little keep the wings well tilted into the cross wind up the bank. 

 

A few spare parts to pick up and the Titan engine to pay for. It ships this month. Nic and I will finish up the UL520t and get it flying then stuck into the Titan build on aircraft 2.
 

As usual the staff were super friendly and helpful. Stayed the night in Hays and even got to attend an EAA meeting. Turned out I was the surprise guest speaker. I was the most surprised of all. Worked out okay with a chat about inventions and the ups and downs of international sales and marketing.

 

They swung the Interstate in and kept the aircraft in Rans factory overnight. Randy made a few repairs and cleaned up some GoPro mounts I had scattered on the rear floor. That’s experience! I never thought about them moving and going into the aeliron cable pulleys nearby.

 

Pics including EAA meeting with an S21 build in the background. The builder taking advantage of factory nearby for painting. I’d do the same!

[Mike Gearon]

Update on the ULengine saga. Nic and I were already very concerned about the 520t.

 

Add to this an unconfirmed crank failure on a zenith last week. The big one was the beautiful twin engine velocity 6 seater we saw at Osh Kosh. Twin 520t motors. It recently crashed back in Florida with the loss of one life. Apparently one engine lost on take off. We don’t know if crankshaft failure or another cause. 
 

With this new information it might be time to commit the Titan engine to aircraft 1. We will discuss! I’m in the market meantime for a Vans side by side tail wheel as French Island commuter aircraft. That’ll also take pressure off feeling we need to be getting the 2nd aircraft flying. It might be waiting the next 12 months or so for a Titan or maybe a Rotax  turbo. 

 

Note…. Continental have stopped making the Nic plated engines. You can have a Titan with steel bore or a Titan with steel bore. 

[RFguy]

I'd absolutely suggest using a Lyco or a Conty. The UL while similar to the Jab,  it doesn't have much case time compared to the Jab which hasnt changed in the bottom end for a long time..... Jabs bottom ends dont give any problem unless their thru bolts break or are not correctly fastened (assuming initial assembly was good) . 
I'd suggest for others a low cost on-condition post TBO Lyco  is still a better bet, if the aircraft can deal with the extra weight, which can be reduced with electronic magnetos, getting rid of the vaccum pump, lightened exhaust system, lightened rocker covers etc  etc.
I would be HIGHLY surprised if the Airmaster was suitable for the UL, since the moment of inertia is miles beyond the listed limit for the Jab engines, and the bearing setup is similar.   
 

[Mike Gearon]

1 hour ago, RFguy said:

I'd absolutely suggest using a Lyco or a Conty. The UL while similar to the Jab,  it doesn't have much case time compared to the Jab which hasnt changed in the bottom end for a long time..... Jabs bottom ends dont give any problem unless their thru bolts break or are not correctly fastened (assuming initial assembly was good) . 
I'd suggest for others a low cost on-condition post TBO Lyco  is still a better bet, if the aircraft can deal with the extra weight, which can be reduced with electronic magnetos, getting rid of the vaccum pump, lightened exhaust system, lightened rocker covers etc  etc.
I would be HIGHLY surprised if the Airmaster was suitable for the UL, since the moment of inertia is miles beyond the listed limit for the Jab engines, and the bearing setup is similar.   
 

Yeah, good point. Re Airmaster….. I recall our conversation at Oshkosh. The jabiru engines with original props being the least problematic. Here we have stuck something rather heavy on the front. We’ve also stuck something on that’s able to very quickly change torque at various RPM settings.  I was told the UL on the Rans had a pitch change at low RPM when it crapped itself. 
 

I was lucky enough to spend quite a bit of time with Randy when visiting. He isn’t a fan of UL or any of the car conversions. He’s experienced 28 engine failures. That’s quite a record! I think a lot of them were 2 stroke. Still, he has an enormous breadth of experience. I think I’ll listen to Randy. However, we do have a GM V8 in the Pawnee at South Gippsland glider club. It’s a healthy sounding V8 throb as it hauls gliders up. I was instantly captivated by it. Current ambition is to become proficient in the Pawnee! That’s one success story. Just now at end of TBO and being rebuilt. I guess the Pawnee is a different story with all that space and weight isn’t a problem on an aircraft designed to carry large loads. They can set up the radiator exactly as needed without concern for the usual aircraft constraints.

 

 

[RFguy]

I suspect a few high profile failures at this stage of market penetration could be curtains for UL, unfortunately.  Yeah, Jab engines with Jab factory props (whether wood or composite) give a statistically insignificant number of reported problems.  Ever seen the big bearing at the front of a lycoming ? a few inches long !  There is a reason for this... Jab also put alignment-fixing dowels onto the crankshaft-prop flange sometime around 2013, also.  So something must have been amiss that we didnt hear much about. 

 

 

 

Edited August 20, 2023 by RFguy

[Kyle Communications]

Mike

 

Why dont you use a 915 IS...lots going in now on S-21 and they are better on fuel and actually faster at altitude than the Titan..also the MTOW is better

 

[RFguy]

yeah 915 is better because there is a turbocharger there.... but hard to go past an O320, surely ??? (or was it a 235 you were looking at ? ) 

what about CG Mark- do they need to move the  propellor location forward to get the same CG range ? (IE without that paperweight Lyco-conty on the front) ? or is the paperweight actually too heavy (or suboptimal)  for it ?

Edited August 21, 2023 by RFguy

[Mike Gearon]

11 hours ago, Kyle Communications said:

Mike

 

Why dont you use a 915 IS...lots going in now on S-21 and they are better on fuel and actually faster at altitude than the Titan..also the MTOW is better

 

I’m leaning very heavily this way. A modern efficient motor. BTW I’m raring to go when I get back and get up to speed. I think your build, Rob Fox and mine about the same stage.

 

I have a hangar to build will probably slow things a bit. Half a day hangar build and half a day S21 build subject to energy reserves 🙂 

[Kyle Communications]

The CG with the 912ULS is a bit tail heavy or so apparently so I have been told..cant tell yet. The one I did 2 flights on was the 912 and it flew fine. The mount for the 915 will be made to suit I would think. The performance with the 915 is supposed to be pretty damn good for the guys gettin them in. Quite a lot now are getting them due to the less fuel consumption and of course the performance at altitude also long waiting time for the Titan and other engines. Patrick Esmond's was the first S-21 to fly here in OZ and he has a 915 in it and really performs. He has a few videos on it and one showing at 10,000 ft he is doing 148 kts TAS !!!! which is actually faster than the Titan

 

[RFguy]

I imagine they'll move prop maybe forward, battery forward , oil tank fwd etc etc all the usual. 
The TAS is good, Mark. 10,000'. Well like I always say, if you fly low you are leaving TAS on the table. (said from a cross country flyer's perspective).  

 

Mike when are you back in Australia ? Stuart and I will make a trip to see you. cheers,

[Kyle Communications]

The battery is on the firewall on the S-21 the issue Maybe I will need to use a Oddysey battery they are very heavy to help the CG. What will be a issue too is I will have the Eprop and it is so light that will make a big difference and the Mrs wants a BRS in it too so thats another problem to solve

 

[RFguy]

Hi Mark

I see some aircraft have BRS fitted behind the instrument panel....

Is the S21 Conty mount just for a generic continental, or is there something specific about a Titan 340cu" ?

Edited August 21, 2023 by RFguy

[Kyle Communications]

I think the engine mounts are similar for the Titan and Continental. I am sure I have seen either installed.

 

Randy has been working on a BRS fitment into the S-21 but I must get onto him and see how that has been going. Not cheap though for a 800kg aircraft but the mrs is pretty keen on one. I am fitting the BRS into Mabel now

 

[Kyle Communications]

If I get flush at some stage in the future I may re engine the S-21 with a 915 IS...but 65k is a bit hard to stuff down my throat

 

[Mike Gearon]

 147kn in the screenshot from that video. That’s amazing! 
 

The good part of our 2 X S21 builds is we split the whole of the 2 down the middle. We take whatever loss on the 520t together and we could even go with the new 916. From last discussion we still install the UL. Nothing to stop us running this for a while then swap it out. It’ll be interesting.

 

 

 

 

 

 

 

[RFguy]

Mark, BTW according to Mr Factory Rotax (at the show)  , while 912, 914, 915 are similar beasts, 916 is new crankcase, new gearbox, new turbo. .....also, old turbo in 914 is no longer available. 

Has your S21 got the big bore 912ULS in it at 10.5:1 ?

Edited August 26, 2023 by RFguy

[facthunter]

I'm NOT surprised THAT is the case. Most aeroengines are made as light as it is possible to get away with. That's part of the ART. Strengthen it when you need to or start again from scratch if it will take no more,  Nev

[Kyle Communications]

The 916 IS  will be about $90k. !!!!!!!!!

 

 

[facthunter]

You wouldn't want to find there were any problems looming. The second hand value would drop fast. It's a hard world for aero engines. Porsche didn't succeed and they built some of the finest high performance aircooled engines ever.  Nev