Aeromomentum has been the subject of quite a bit of discussion here. Do a search of this site and you'll find much more, if you are interested. They seem like good powerplants and Mark Kettering has provided information here that appears, to me, to be free of hype.
http://www.reaa.ru/yabbfiles/Attachments/PICT4970.JPGI've been following this company's progress for a while, and I have yet to see their 3-cylinder engine run. I can't find a video of it on Youtube, on their Facebook page, or anywhere else.
Thanks for the video. IMO, Mark Kettering does a good job here of explaining whey they chose to convert Suzuki's rather than some other brand/model of engine (weight, and the "right" mount of complexity for aircraft use). I'm surprised he didn't add the fact that these are still in fairly widespread production around the world, so parts are still available.
I am not an expert in Megasquirt/Microsquirt, and so these are perceptions/anecdotal accounts, not experience-based facts:What are your concerns with microsquirt?
I want to run an open-loop EFI (i.e. no lambda sensor) so I can burn 100LL without destroying a lambda sensor and inviting more problems.The Megasquirt relies, for some things, on memory that that can be erased. Sometimes it happens for reasons that are not identifiable--here's the experience of one user. Look around on the "Tuner" sites and you'll find more. Megasquirt sounds like a fun system for an auto enthusiast who likes to fine tune things and isn't bothered by the occasional failure of the engine to run. These are not the criteria most aircraft builders use, and one reason that systems like this aren't more popular.
I am not an expert in Megasquirt/Microsquirt, and so these are perceptions/anecdotal accounts, not experience-based facts:
From a previous post:
I want to run an open-loop EFI (i.e. no lambda sensor) so I can burn 100LL without destroying a lambda sensor and inviting more problems.
I want rock-solid hardware. That is, proven to work in a high-electronic noise environment, components selected for high temp use.
I want a system that has engineered-in capability to provide enough engine power to remain airborne even in the case of multiple sensor failures (and not just "null" failures, but erratic responses, out-of-range errors, etc).
I >don't< want a high-level processor running a fat program with lots of features and complex interdependencies.
These are attributes that I'd guess are not "mission critical" in the "tuner" community, where flexibility and ability to optimize are more important.
It appears to be the Suzuki G10, which is of the same engine family as the G13 (AM13) and the G15 (AM15). The G10 was used in the Geo/Chevy Metro in the US, and (AFAIK) is still being manufactured overseas.Billski or anyone else, does anyone know what engine the 75 hp AM10 is based on? It appears to be different from the others.
The video mentions Bosch electronics and was apparently made before Aeromomentum starting using the Microsquirt system. Customers get an engine with the Microsquirt installed and the engine test run, which is nice. For a customer buying an Aeromomentum engine and wanting an SDS ignition/FI system, the optimum situation (IMO) would be for it to be installed and test run before it is delivered. With a newly manufactured engine, that seems like the best way to avoid a lot of finger pointing and head scratching.Mark Kettering cites the number of engines built and hours of operation in this video: https://www.youtube.com/watch?v=xWOj5_0DoQI
They begin to look like they have enough engines and hours for me to consider their engine and PSRU reliable. I still would prefer a dual alternator and SDS running the engine...
Monty, thanks for the firsthand report. Maybe I didn't sufficiently caveat my post. I'm not a Megasquirt basher, I wish them success. But, as you point out, anybody counting on that system to keep their airplane aloft needs to go in with their eyes wide open. They need to not only know stuff, but "know what they don't know." And, IMO, that includes an understanding of the software architecture used in Megasquirt, which is the only way to appraise its stability and response to various sensor failures (none of us can hope to accumulate enough time in our own car to find the failure modes that may occur in an airplane, though it looks like you are doing your part!). As a user, is it possible to "engineer" a Megasquirt system? I don't mean install various bits and make sure they run, but look at the source code and truly understand what is happening inside the black box?It seems fashionable in some circles to bash Mega/Microsquirt.....usually people who have never used it, those who are selling something else, or people who tried to use it and failed. Or people who for some reason listen to any of the former.
I've been running it on my vehicle for 5 years....Mostly to gain experience with the system and evaluate it in a non-critical application. During that time, I've experienced multiple sensor failures, and even an alternator failure. I drove for 30min with no alternator just on the battery-no problems. I've run it open loop, and closed loop. I've even run Avgas through it. So far the computer has been the least troublesome part of the whole thing. I'd run it in an airplane. The installation is as good as the installer. Megasquirt does many of the things you are talking about, and it can be as simple or complex as YOU make it. However, the onus is on YOU to make it work. None of the other systems out there (Haltech etc) are going to be any better, in this regard. They are also going to cost a LOT more and still have many single point failure modes and inter-dependencies. I'll take a "fat" program and computer with most of the "fat" disabled that is proven.... over a "skinny" unproven system ANY day.
I suggest SDS if you don't want to take on the responsibility of engineering your own system.
You'll still need to do a good job installing it.
Those who do not know how to use an O-Scope, properly crimp and solder, or read a schematic should stick to mags and a carb, or use a pre-engineered solution. I'm dead serious about that. People with no background in electronics have ZERO business trying to install a custom fuel injection system in their airplane. It borders on insanity, and the cost of failure is VERY HIGH. Most of the time I see people complaining about mega/microsquirt on cars it's due to this problem. I do have a background in these things, and I still wanted to test it on the ground first.....
If it doesn't work.....most people blame the hardware, not the installer/tuner.
In my life as the transmission vibe guy at Ford, I can not tell you how many times I tried to make use of an existing sensor and found the sensor was absolute crap. So much so that the calibrators had to average the signal over a second or more to get a reasonable estimate on how fast a particular shaft was turning, much less know exactly when the tooth went by for my work at vibe sensing or spark timing. There have been a lot of crappy sensors used in cars because they could get by with them. I fear that a lot of these sensors may be convenient and available and then folks try to use them with other stuff. The result is incompatible setups.... I've assisted a couple people over the years with MS trouble shooting, in both cases it turned out to be noisy crank sensor signals causing false triggering ... The factory EFI worked just fine with these factory crank sensors being used. ... Noise is a top concern on ECUs, especially those used in aircraft ... I'd do lots of bench testing with these bits close to the ECU, wiring and sensors to make sure nothing crashes or glitches. Won't be good to find out in the air.
Yup, we've seen some really crappy (but expensive) sensors which failed in a few hours literally.In my life as the transmission vibe guy at Ford, I can not tell you how many times I tried to make use of an existing sensor and found the sensor was absolute crap. So much so that the calibrators had to average the signal over a second or more to get a reasonable estimate on how fast a particular shaft was turning, much less know exactly when the tooth went by for my work at vibe sensing or spark timing. There have been a lot of crappy sensors used in cars because they could get by with them. I fear that a lot of these sensors may be convenient and available and then folks try to use them with other stuff. The result is incompatible setups.
You gotta have good sensors for things like crank position. Noisy sensors are just going to poison the rest of the system. Now who do we know who carries only unconditionally "good" sensors and hardware to go with it?
You are maybe thinking of VR sensors with a flying reluctor. Hall Effect has neither a magnet nor wire wrapped around it. A flying magnet on the flywheel or crank pulley triggers it.I've had a few Hall sensors die in "non-linear" ways where it woulf fail then work then fail.
So Ross, do you literally wrap your own magnets with wire?