SonexBuilders.net

Hey everyone,

While at KOSH, I checked out Aeromomentum engines, especially this 100hp one:

http://www.aeromomentum.com/am13.html

https://photos.app.goo.gl/XtEmAJHnwKZzPXLu8

Has anyone checked them out and/or tried one in a Sonex?

My camp partners were saying good things about these people. They source "old-fashioned" engines from China that have a single overhead cam and no variable valve timing, for simplicity, and their redrive is structurally independent from the engine crankshaft and connected by a rubber donut so the crankshaft is not subjected to off-design loads.

Ihab

Hi ihab
I’ve been looking at alternative engines and really like their offering. They seem to have some experience behind them and use the suzuki g13 engines. Not the most modern design, but still more advanced than most.

Glad you were able to get out to OSH this year.

My hangarmate is in the process of installing an AM15 engine on a LSA amphibian. The engine package looks very good.

I exchanged some notes with Mark Kettering, the owner of Aeromentum, a few months ago. At that time, he was working with one Onex owner one Sonex-B owner, but I don't know how far things had gotten.
According to him, the AM13 (1300cc, 100HP) engine package (engine, PSRU, radiator, coolant) weighed 201 lbs, but i don''t know if that included the exhaust system (my guess: no).

He responded quickly to my questions and was helpful. Others have also had good responses from him that seemed honest and free of hype.
The engines look good and they (and the PSRU) have gotten a LOT of time on airboats.
Some things I would want to resolve:
- Single ignition system and single electronic fuel system. Neither is Suzuki stock (i.e. engineered/tested with large corporate research $$) and I don't know how much testing they've had in the air. Yes, OEM automotive EFI/EI systems are very robust and problem free, but this isn't OEM. The hardware (connectors, circuit boards, chassis, wiring) has got to be 100% bulletproof. Likewise, the software has to be designed and tested for aircraft use (i.e. able to overcome failure >or< aberrant readings from sensors and provide a "limp-home" mode that truly allows safe flight). Maybe Aeromomentum has all this stuff worked out, but it's not easily accomplished.

vigilant104 wrote:... the M13 engine package (engine, PSRU, radiator, coolant) weighed 201lbs, but i don''t know if that included the exhaust system (my guess: no). He responded quickly to my questions and was helpful. Others have also had good responses from him that seemed honest and free of hype.

I concur with the honest and non-hype-filled presentation from these folks. What they told me at OSH about the AM13 is:

* Base price $8,495 upright, $10,495 low profile
* Base weight 170 lb
* Exhaust $260 extra
* Radiator $245 extra
* Mount $800-$1000 (Sonex would be on the low end of that)
* Total FWF weight about 195 lb

vigilant104 wrote:Single ignition system and single electronic fuel system. ...

Yes, I noticed that. They replied that in their view, modern systems are reliable so they are not worried, and they pointed to their years of trouble-free operation on airboats, which is fair enough. Of course for aviation use the limp-home redundancy is more important.

I think that, on some level, we have to trade money for safety. In some sense, are already doing that when we buy a small aircraft like the Sonex rather than a turbine with FIKI that goes IFR in the flight levels. :) Again, I didn't get a sense of hype from the vendor, but it's certainly a personal decision that everyone needs to make independently.

They said they use MicroSquirt for their EFI/ignition so at least it's a commonly available and understood system with a community around it:

http://megasquirt.info/products/pro-con ... crosquirt/

That should be quite appealing to engine hackers everywhere! :)

Ihab

The other Xenos being built here at the Melbourne airport has an Aeromomentum engine hung on the front of it. He will be using a feathering Woodcomp prop. I would guess the other Xenos will be ready to test fly within 6-9 months. He built his engine mount and it really extends out far. I have never seen so much space between engine and firewall, ever. He said a lot of that was to balance the lead weights he has for his counterbalanced ruddervators (and ailerons) he made. This will be interesting to see when it takes to the air.

Rick Caldwell
Xenos 0057
CAMit 3300/Sensenich

ihab wrote:They said they use MicroSquirt for their EFI/ignition

Interesting. My experience with the Microsquirt in converting a motorcycle to EFI has been quite positive, I've been toying with the idea of converting the Aerovee to EFI using it, but they do have a disclaimer that says "for OFF ROAD RACE-ONLY ground-vehicle use only" so if you come and ask questions about an aircraft installation they might not want to touch you with a ten-foot pole.

Check out Sonexpodcast Ep 40b. There's a long bit on aeromomentum engines. As a first time builder way over my head, I'll probably stick to the jabiru, but the aeromomentum is a very tempting alternative.

I am quite interested in the Aeromomentum engine. As the thread indicates there seem several Sonex builders working on installations. Any updates?

At Oshkosh Mark Kettering indicated that a Sonex (don't recall if it was a Legacy or B-model) was in the process of hanging the engine. Sounded promising that they would have a FWF package available in the near future. I've been trying to get a hold of Mark via email but no response yet. Anyone hear anything?

Mike Fazio
Waiex #63
Wings, tail, aft fuselage - Done!
finishing up Fwd Fuselage.

Mike,

There is another Xenos being built a few hangars down from mine and he has the exhaust, cooling tank, radiator with cowl flap now installed. I guess the fuel pumps are going on now. This is an A model Xenos but he has told me he is up to #45 on his modifications. This is experimental aviation if there ever was a definition. If you want a picture, I could do that. But like I said, this is not a typical Sonex build.

Rick Caldwell
Xenos 0057
Melbourne, FL