Big upgrade coming

When it comes to FADEC, have you looked at how many connections will be made to the engine and where they are made? The equipment and systems that will be added. It's adding a very complex piece of equipment to the engine. For those of us that have taken the time to know how to properly operate the engines, I don't want it. The reason it has taken so long to certify is because of it's incredible complexity. If one system fails in flight, guess where the engine gets parked?

Just like a manual transmission, I prefer for it to be where I put it and don't want the extra adjustments, maintenance and complexity of a new system I don't fully control. I can hear pilots now saying: what's it doing now? Why's it doing that, etc. Good from some maybe as it simplifies operations, but if it isn't working just right, hang onto your wallet.

Best,

Dave
 
The thing is, you do realize just how many times every day your life is in the hands of computers, right? From the moment you start your car to every time you get into an elevator. It's pretty easy to forget to open a manual wastegate or to open a cowl flap. I'm not saying they aren't complicated or that nothing can go wrong, but if there were a high failure rate...I have a feeling that the "Cirrus kills people" pundits would be tromping all over FADEC as a reason that these people keep leaving smoking craters in the earth.

I tend to like my controls manual as well, but that isn't a reason to dismiss FADEC. I have yet to see any trend showing anything other than a positive experience with them. The only one that I can think of is where the DA50 had both engines shut down because of a low battery, but that was also in the POH (and he didn't follow it), so it's hard to blame FADEC for that one.
 
That failure was on a DA42 and you are correct, it was a problem with how the system was installed combined with operator error rather than the computer itself. That said, the same plane with mags and mechanical fuel would've kept flying. However that's only one example, which doesn't state a rule. Ultimately, the problem was the pilot, proving that computers can't solve all pilot-induced problems. You are absolutely correct that a computer does remove the least reliable component. I'd also suggest that the reliability of that component is of very high variability.

As usual, I think Dave has a pretty good summary of the issue. I don't think he's stating a lack of trust of computers, simply pointing out some of the inherent disadvantages.

Also, keep in mind that virtually all of the computers in use today are on turbines, with the exception of a couple of diesels out there, the IOF Continental engines, and the Lycoming iE2. The requirements to control a turbine or a diesel are actually significantly simpler than a piston spark ignition engine. So, I'm not sure there is yet a sufficient sample size to state overall satisfaction or dissatisfaction. However, I don't see the IOF Continentals in use in many planes out there.
 
FlyNE said:
The thing is, you do realize just how many times every day your life is in the hands of computers, right? From the moment you start your car to every time you get into an elevator. It's pretty easy to forget to open a manual wastegate or to open a cowl flap. I'm not saying they aren't complicated or that nothing can go wrong, but if there were a high failure rate...I have a feeling that the "Cirrus kills people" pundits would be tromping all over FADEC as a reason that these people keep leaving smoking craters in the earth.

I tend to like my controls manual as well, but that isn't a reason to dismiss FADEC. I have yet to see any trend showing anything other than a positive experience with them. The only one that I can think of is where the DA50 had both engines shut down because of a low battery, but that was also in the POH (and he didn't follow it), so it's hard to blame FADEC for that one.
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Jason:

The last time I looked at FADEC was from the perspective of a twin turbocharged piston owner. Myriad new connections from EGT to fuel probes. My point was, especially on more complex planes, there were many new connections on a vibrating piece of machinery in a stressful environment. I frequently have CHT/EGT probes fail.

Two points: if somethings goes wrong connection wise, where does the engine get parked? In a car, one can pull over to the side of the road; a bit different in a plane. If I'm flying over the Gulf of Mexico and have a max range setting in and some point of measurement fails on FADEC, can I still make shore when it goes full rich?

Second point is I can currently select a number of power settings based on range/speed considerations that may not be in the FADEC algorismic formula. Do I wish to give up those selections? The cost of simple operation is giving up options many may like having. I won't discuss cost, but it's not cheap.

BTW, this is from an operator that has taken their last and current plane well past TBO operating in manners very different than what's called for in the POH and how FADEC would be set up.

Best,

Dave
 
I think about FADEC from a capabilities point of view. Even in my DA40 with only 4 cylinders to think about, every power setting and every mixture setting is a compromise to the average CHT/EGT - which has a pretty broad spread even among my 4 cylinders. I even have GAMIs that were supposed to even those things out, but they don't. FADEC takes care of that for me and allows me to be very precise and even handed on how much power vs fuel flow vs wear I want for the engine and it takes care of keeping those forces in balance. Kind of like having a throttle and mixture control per cylinder but without the hassle.
 
Art Fritzson said:
FADEC takes care of that for me and allows me to be very precise and even handed on how much power vs fuel flow vs wear I want for the engine and it takes care of keeping those forces in balance. Kind of like having a throttle and mixture control per cylinder but without the hassle.
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You're right - FADEC takes care of that - but most of them don't ALLOW YOU to be very precise. Instead they are precise to the maps that they were programmed with which may or may not be in your best interest depending on your mission.
 
I really like some of functions of the FADEC, push the button and it starts, push another button and you are LOP.

I don't want to be one of the first to convert, the first systems of such a radical change will lead to many teething problems.

Kevin
 
A broad EGT/CHT spread isn't necessarily a problem. There's probably a 100 degree spread between the hottest and coldest cylinders on my Aztec. What's important is that they have the same air/fuel ratios per cylinder, i.e. peak at roghly the same point. The spread has more do with uneven cooling.

Engine control computers have a pretty wide range of what they can and cannot do. As with any other system on the plane, it's important to understand how it works and what its capabilities are and are not.
 
jesse said:
You're right - FADEC takes care of that - but most of them don't ALLOW YOU to be very precise. Instead they are precise to the maps that they were programmed with which may or may not be in your best interest depending on your mission.
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My point precisely. Now, if FADEC is set to mirror POH numbers, or the numbers TCM has recommended for the operation of my engines in the past, hold on to your wallet. I'm sure you'll be getting Christmas cards and thank you notes from cylinder manufactures.

Best,

Dave
 
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