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View Poll Results: Hypothetically if you were selecting your engine right now, would you consider FADEC?
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Never! I learned to fly with mags and a carb or mechanical FI, and I'll never trust anything else.
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9 |
4.50% |
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Nah... I've warmed up to electronic ignition, but electronic FI still gives me the heebee-jeebies.
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18 |
9.00% |
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Maybe some day. Sounds good, but I'd want to see more of them flying before I'd take the plunge.
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40 |
20.00% |
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Maybe if the price is right. Sounds good, but it needs to come down in initial cost.
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83 |
41.50% |
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Heck yeah, give me! I love the benefits, and I'm willing to pay for it. Cheaper in the long run.
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46 |
23.00% |
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Other. What did I miss?
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4 |
2.00% |

01-14-2009, 01:26 PM
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Join Date: Jan 2006
Location: Saskatoon, SK, Canada
Posts: 202
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fadec in experimentals/homebuilt
thanks for the interesting read.
A helicopter has been on my list since I was a kid, and I've followed Rotorway over the years.
The later Exec and now the Talon use redundant FADECs.
http://www.rotorway.com/fadec.html
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If I was happy with the failure and fallback modes, the service record and the price, I'd strongly consider using a FADEC. For me, storage/service temperatures are very interesting, as well.
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Howard McKay VAF 573
RV-8A, empennage/wings
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01-14-2009, 06:02 PM
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Join Date: Jan 2005
Location: Cape Elizabeth ME
Posts: 139
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The only thing that keeps a fadec system form being produced is LIABILITY, companies can't even get insurance for producing 1900's technology (carbs) it would be a pretty foolish business model to try to develop a system knowing that the line of ambulance chasers would be just waiting for the first crash. The technology is available, the need is there, it would take a brave company to assume the risk.. just my opinion
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Bob Collins (the other Bob Collins)
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01-14-2009, 06:17 PM
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Join Date: Mar 2005
Location: Calgary, Canada
Posts: 5,766
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Quote:
Originally Posted by rvator9a
The only thing that keeps a fadec system form being produced is LIABILITY, companies can't even get insurance for producing 1900's technology (carbs) it would be a pretty foolish business model to try to develop a system knowing that the line of ambulance chasers would be just waiting for the first crash. The technology is available, the need is there, it would take a brave company to assume the risk.. just my opinion
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The technology is not only available, it's in production. One company has been making FADECs for certified pistons engines for a number of years now and Lycoming will soon be releasing its IE2 engine line which are FADEC equipped. Liability concerns were not a deciding factor here since these systems are or soon will be in production and use. Several other companies use FADECs on their engines as well, notably Thielert and Rotorway.
Vendors for products destined for the experimental market may have liability concerns but there is far less likelihood of a successful lawsuit being brought in this market IMO. However, anyone can be sued for almost anything!
Last edited by rv6ejguy : 01-14-2009 at 06:45 PM.
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01-16-2009, 05:02 AM
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Join Date: Oct 2006
Location: Melbourne, Australia
Posts: 427
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liability
To some extent, the liability is a complete non-issue for the incumbents. In fact FADEC would reduce their liability, not least because the risk of carb-ice related incidences would diminish.
The liability issue does scare off newcomers though - I know this because I've tried to convince some who could do it well to entertain the FADEC idea and the answer is a firm "no thanks"
A
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01-16-2009, 06:58 AM
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Join Date: Dec 2004
Location: Southlake, Texas
Posts: 626
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Not really needed
Unlike cars, aircraft engines spend most of their time at a steady power setting. The efficiency benefits of FADEC in cars simply is not as great in aircraft. After you fly your RV for many hours, you will know where to put the knobs at first power reduction. After that, fine tuning is all that is required as you change altitude.
Most engine and prop combinations have a sweet spot where operation is the smoothest. In the Doll that is 2350 RPM. I used that RPM 99% of the time while in cruise. If the Doll were FADEC, the computer might select a different RPM that might be slightly more efficient, but not as desirable, and I would have no way to change it.
I use LASAR ignition so I have the best of both worlds for ignition. LASAR gives you the benefits of electronic ignition with the complete independent backup of dual magnetos.
I have never had any problems starting my I0360 A1B6 hot or cold. Once you learn your engine, starting is easy. IMHO FADEC is not worth the cost and complexity for homebuilt aircraft.
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Danny King
Beautiful Doll 80434 TT 1675 hours
I0360 A1B6 200 HP
Christen Inverted Oil
First Flight 12 July 2000
VAF Dues current for 2020
Last edited by Danny King : 01-16-2009 at 07:10 AM.
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01-16-2009, 08:58 AM
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Join Date: Mar 2005
Location: Calgary, Canada
Posts: 5,766
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Yes, I've mentioned this before, in cruise, gains are minimal. We find most of the lower fuel flow happening in the start, taxi, takeoff and climb rather than cruise.
On turbocharged engines, the gains are larger due to both fuel and spark being optimized collectively. Independent EIs can't match integrated systems in this respect since they don't know what the pilot is doing with mixture.
Last edited by rv6ejguy : 01-17-2009 at 03:53 PM.
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01-16-2009, 09:44 PM
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Join Date: Jan 2008
Location: Wellington, New Zealand
Posts: 97
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Perhaps the gains/benefits are greater for low time pilots, and for aircraft that get rented back to clubs, or with shared ownership. Knowing the next guy to fly your plane won't be wasting gas or mistreating your engine has got to be worth something.
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01-17-2009, 06:28 AM
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Join Date: Oct 2006
Location: Melbourne, Australia
Posts: 427
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disagree with the "not really needed" view
It's true that aero engines run quite efficiently in the cruise when operated LOP with a full engine monitor etc, but I think that's missing some of the point. I think of FADEC as an enabling technology, where you could run MOGAS (or unleaded AVGAS) at 9.5:1 compression ratio with complete safety. When you start doing that things like that the fuel consumption benefit starts to grow fairly significantly, even in the cruise.
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01-17-2009, 09:34 PM
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Join Date: Feb 2006
Location: San Diego, CA, U.S.A.
Posts: 770
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Great discussion!
Wow, I'm really pleased at the response to this thread and poll! We got a great discussion going with many points of view, and learned a lot about FADEC, and about people's perceptions of FADEC.
I'll try to summarize, and respond, to some of the key topics that came up so far in this thread. Now, I won't claim to be impartial. Clearly I'm a proponent of FADEC, as I've said before. So my responses are just my point of view. Feel free to disagree  . The following "quotes" are not really quotes, they are paraphrased by me:
1. "I actually enjoy manual engine management, like twiddling with the mixture knob" or "having a mixture knob invokes pleasant feelings of nostalgia".
If that's how you feel, I certainly can't argue with that. We all find enjoyment from different aspects of flying, and that's just fine. Enjoy!
2a. "A well trained pilot should be able to adjust the mixture as well or better than a FADEC".
That, with all due respect, is simply not true. A well-designed FADEC system could adjust the mixture far more optimally than any human pilot (yes, even one as good as you ), individually per-cylinder, and fine-tune it continuously, literally on a cycle-by-cycle basis.
2b. (corollary to 2a) "It won't let me manually adjust the mixture."
Right. Neither will your car, and it seems to run pretty well. You don't need to adjust the mixture manually because the FADEC can do it better than you can, no offense. Unless you simply enjoy manually adjusting the mixture, which is fine (see number 1).
3. "A FADEC may be beneficial for newbies, but not so much for experienced pilots."
It's not just about how proficient you are with the mixture adjustment. Even if hypothetically you could manage the mixture equally well as a FADEC (in your dreams ), one of the most important benefits of FADEC, in my view, is that it simply removes much of the tedious aspects of engine management from the pilot's workload. It does the mundane repetitive tedious stuff (the stuff computers can do better than humans anyway), so that you don't have to. The FADEC allows the pilot to monitor and manage the engine at a higher level of abstraction, and therefore leaves more of the pilot's time and attention to devote to other aspects of the flight (navigation, traffic, etc.). That's a good thing even for the most experienced pilot. Reduced task loading, increased situational awareness, increased safety.
4. "FADEC is more complex than traditional FI and mags."
Well, there are different kinds of complexity. It's a trade-off. FADEC systems are much more complex electrically. That is true. But most of that complexity is handled by the engineer who designed it, not by the airframe builder, and not by the pilot. FADEC systems are far less complex mechanically, with very few moving parts, which is a key factor in their potential for better reliability than the traditional systems. FADEC is also far less complex operationally for the pilot, as I discussed above.
5. "Look at the problems some of the electronic ignition products have had."
Yep. Just because a technology is fundamentally sound, doesn't mean that every product on the market will be sound (this is true with any technology). Without going into specifics (no vendor bashing here), some of the troubles in the EI arena seem to have been the result of shoddy engineering practices and/or lack of sufficient product testing by some of these vendors. In the experimental market especially, some products are designed by highly qualified professionals, while other seemingly similar products are designed by not-so-qualified dabblers and tinkerers. Sometimes the results are still very good, sometimes not. It really depends on what the individual was willing to put into it. Some vendors are also more forthcoming than others about what they've done and what they haven't done to ensure the quality and robustness of their product. Ultimately, the freedoms we have in building experimental aircraft also come with a responsibility to ourselves to do our homework and make educated decisions about what equipment we install in our aircraft. Not all EI's are created equal, not all FADEC's are created equal. Insist on a product that has demonstrated its merit to your satisfaction.
6. "FADEC is too expensive."
Yes, it is still significantly more expensive than the traditional systems. Presumably, reduced operating costs over the life of the airplane would offset at least some of that initial investment. But still, yes, that's a lot of extra $$$ to fork upfront, and for many of us (about 40% of us according to the poll), that has been the deal breaker. It's the classic catch 22 for the vendors. To bring the cost of a product down, the vendor has to sell a greater volume of units. And to sell a greater volume of units, the vendor has to bring the price down. It seems that with Aerosance, the gap was just too big for the product to reach a viable critical mass in our market, and so they finally gave up. But what our poll shows as sort of an informal market survey is actually very encouraging. It shows that if the price was lower by a sufficient amount, over half of us would buy it. Last year 600 new RV's flew, so if this poll is representative of the group, that's potentially 300 FADEC units per year. That's more than Aerosance has sold, ever. I'm hoping, since the demand apparently is there, at least at some price point, that Aerosance/TCM and/or other vendors will try again to have a go at it in the future.
7. "It's cost and/or liability that keeps companies from developing FADEC products."
Well, Aerosance did it, and others are doing it.
It takes time and money to develop a product. But once that's done, it can be manufactured for a pretty low unit cost if you make them in sufficient numbers. A FADEC system in principle could be manufactured even less expensively than the traditional systems, because it's mostly generic electronics (cheap!!!) rather than specialty mechanical parts (expensive!!!). For things like coils or injectors, it can leverage from the automotive market, which has made these parts relatively inexpensive too due to high volumes.
As for the threat of liability, that concern is always there for anything and everything having to do with aviation. Still, many courageous businesses thrive in aviation, and they do what they think is necessary to protect themselves legally. The liability issue is a pain in the a**, but it's not insurmountable.
8. "Anyway, so Aerosance is out for now, what else is out there?"
Well, there's Lycoming's iE2 on the horizon, although it sounds like they'll be targeting it only for their bigger engines, at least initially. There's also the Eagle EMS from Precision Airmotive, which I'm looking forward to learning more about. There may be other products, I certainly don't mean to exclude if there are. I personally have just been focused on Aerosance for some time, so now I'm back to the drawing board and re-investigating what's out there.
Great stuff!
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01-17-2009, 10:27 PM
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Join Date: Mar 2005
Location: Calgary, Canada
Posts: 5,766
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Pretty fair summation from where I stand (15 years in this field). Hopefully some much lower cost units will be available in the next 12-18 months for the experimental market.
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