Siezed low-time neglected turbocharger

[John Monnett]

Most current turbos in cars are water cooled. After shutdown they rely on convection cooling. Most, if not all, use synthetic oils and, of course, Mogas. As our service bulletins state, running with full synthetic and Mogas will reduce the coking as in cars. Again, Rotax is running Mogas in it's turbos and it works. Certainly, Aerovees can run Mogas. The downside is a lot of airports don't provide Mogas. Our challenge is lowering shutdown temps so we can reduce or eliminate coking with avgas and semi-synthetic oils. We have a significant breakthrough with our latest stand-alone cooling system.

[kmacht]

Mark,

How many flight hours (not test cell hours) were put on the turbo system before it was sold to the public and how many hours are you planning on putting on the new cooling system before offering it as a final solution? Also, are you holding off on selling turbo engines until the fix is in place?

Keith
#554

[sonex1374]

To all following this thread, and especially the current Turbo users,

Let's not loose sight of the fact that we've asked for Sonex to remain involved in working through the issues that have surfaced on the turbo, and they have responded. Their latest update shows the depth to which they are studying the problem, attempting to peal back some very complex dynamics and understand the root causes, and working to craft solutions. They've been a partner in this process, and have shown that they are committed to the long term viability and success of the turbo. Far too many other companies have released products that had issues surface some time after getting into the hands of users, only to discontinue support of that product and start selling a completely new and "improved" one all together. Sonex isn't doing that....they're slogging it out in the trenches, and we all benefit. Let's give them time to work, and approach this with professionalism and understanding.

Products that manure over time often have costs associated when changes are made. Look at how Lycoming, Continental, Rotax and Jabiru approach service bulletins. They very commonly have mandatory replacement parts that must be purchased and installed at the user's cost. I don't like this any more than the next user, but I understand the position the manufacturers are in. I think Sonex's approach to the turbo is in line with other industry practices.

To John and Mark at Sonex,

Thank you for sharing your detailed R&D work with us. It's encouraging to see the magnitude of time and resources being brought to bear on crafting a comprehensive, well engineered system. Please keep up the good work, and keep communicating your progress with us. It's confidence-inspiring to get regular updates directly from you on how things are progressing. This latest development step will take time to fully test, to build flight hours on and to analyze, and there will be a lot of people intently following your reports.

Jeff

[andrewp]

To follow on from Jeff:

I don't even have an aerovee and I am in the middle of dealing with modifying the X adaptor so I can check the my flywheel screws bla bla ON A JABIRU (else it turn into a flying disk)! My elderly182 just got an AD written up against it for when it hits 4000 hours and it has been around since 1962. There is no perfect solution here, but what the turbo guys (and what I mean by that is all the folks that are trying the turbo) are trying to make another path that otherwise wouldn't exist. Ok, that might be a bumpy road, but you are down that road. I totally understand the customer vs supplier thing and we all want what we want, but the grass is not greener. I was just saying to Rose this morning that flying an airplane is hard and it has nothing to do with flying the airplane. She nodded sagely.

I don't have a dog in the fight, but I think folks are genuinely trying here. Regardless of how we got here, it seems like everyone knows more about this than when we all started. Why don't we see where this all goes. If the cooling things does its thing, then this is a step forward.

And when you guys say "but I paid all this money and time", dudes, you have no idea what you are talking about. Try owning a certified aircraft. ;-) You are all adorable. [Insert: I mean this with the greatest of affection for all my fellow builders, but I doubt you are head down banging my head on my desk last week, when my trusted A+P died of a stroke with our airplane in his hangar... it is still there]

Cheers,

Andrew

[Bruce593SX]

To all following this thread, and especially the current Turbo users,

.......

Jeff

+1 to what Jeff posted.

My Sonex, with Turbo, is just sitting in the hanger 99% done - Waiting for this to be resolved. (My recent purchase of a Bellanca 260 in need of extensive annual and upgrades has alot to do with it as well... all of the last 6 months of my "airplane time" has been devoted to the Bellanca)

I'm very encouraged by the progress being made by Sonex and am patiently awaiting the resolution.

[Bryan Cotton]

I am also glad to see a resolution being worked. I still plan on a turbo, either after 5 years of flying without or after paying for college, whichever comes last.

[John Monnett]

Since the question as asked, here's the way we acquire the temp data: Thermocouples are attached to the bearing housing thermostat and the turbine housing as well as one thermocouple mounted to measure cowl ambient temps. We use the open channels of our MGL's normally used to measure EGTs and CHTs. Custom display elements were created to display on our screens.

[NWade]

IMG_0358.jpg

Since the question as asked, here's the way we acquire the temp data...

Thank you for opening the communications channels a bit and providing us insight into the testing and development procedures you're using (as well as already addressing some of our earlier questions already).

I know we're all going to be asking for more data & details than you can provide at this point, but I do have one more question about your testing procedure: With these ground runs I'm sure you're using some kind of metric as a "cut-off" to determine when to shut the engine down. Are you watching for a particular CHT temp? Turbine housing temp? Engine run-time? Something else?

With appreciation for the community engagement,
--Noel

[rizzz]

One comment, one concern.

Start with the comment:

For those who claim other companies make you pay for SB services and parts, that’s not always the case. I know this for a fact.
My hangar buddy is completing his RV-7A project. He’s got a brand new Lycoming engine that has not run yet.
Perhaps some of you might have heard of a recent Lycoming mandatory SB affecting a certain batch of engines, if I remember correctly it had something to do with the wrong bushings having been used on the conrods ?
Anyway, the engines affected required partial disassembly, inspection and perhaps replacement parts if they are found to be faulty.
My hangar buddy's engine was one of those and since he bought his Lycoming through Vans and they will be paying for this, but I’m sure they will in their turn claim back their cost from Lycoming.
Anyway, it might depend on the circumstances but here’s at least one example I know for a fact where the supplier pays for services and replacement parts caused by a mistake on their part.

Now more importantly, one major concern I have with the proposed solution:

That electric fan. Those things are very sensitive to moisture and they do short out when exposed.
I know this from experience because I was a Bitcoin miner and owned an Antiminer S9 up until a month ago or so when I sold it.
If you don’t know what an Antminer looks like, just google it. You’ll notice they have 2 very similar 4.5” fans on the front and back of these units, 6000rpm on the front and 4500rpm on the back (they produce a lot of heat so require serious cooling).
Anyway, my miner was set up in the garage and because of the heat and noise these things produce. I had my miner draw air from the outside through air conditioning ducting which I had running uphill and I also had a filter in the system to minimize moisture.
Still, in the space of a couple of months I’ve had to replace the front fan of the miner twice because moisture had crept into the centre coils/electronics and shorted out the thing. This would happen after a foggy or rainy day so I stopped running the miner on those days.
Now we know the Sonex cowl is not weatherproof, at least not my older vertical split version, so, to ensure this time things do not happen “outside the scope of testing”, can I suggest you fly the test aircraft sufficiently through foggy and rainy conditions and see what effect it has on this fan?
After all this, the one thing you would not want to happen is have your customers stuck with a solution where they have to replace the fans of these units every couple of months.

[John Monnett]

The primary is the turbine housing temp. Of course running extended high power full boost runs are necessary and very hard on CHTs... far more stress than flight! That's why the ground runs provide very valuable data. I am happy to engage the community
as long as the discourse is civil. Keep in mind that there are some proprietary aspects of R&D that will never be disclosed.