Climate change

Silvaire wrote:

Once you start going down this road the complexity piles up and you end up with a car engine, which despite my current involvement in car style engines being used in aircraft is not at all what I want in my own plane.

As Peter points out, there is a difference between spending somebody else’s money and spending your own. For the latter and for decades of long term ownership, the market says simple is good.

Amen. As someone who actually flies behind a FADEC (Aerosance) Lycoming, my plan B for dealing with any FADEC issues that can’t be solved by replacing the ignition modules (for which we have spares) is to rip out the whole thing, revert the enginge back to a standard IO-360, and put in at least one P-MAG and keep a traditional magneto.

In 30 years it’s highly likely to be able to service a magneto and fuel injection system, but how many of the older and newer electronic ones will still be supported? Since ten years, our FADEC is unsupported, our engine monitor (VM1000C) which takes the serial FADEC output (undocumented protocol and format of course) is unsupported and the manufacturer is gone, our EFIS (BlueMountain) which can display some engine data is also unsupported with the manufacturer gone and bust …

Sebastian_H wrote:

Since ten years, our FADEC is unsupported, our engine monitor (VM1000C) which takes the serial FADEC output (undocumented protocol and format of course) is unsupported and the manufacturer is gone, our EFIS (BlueMountain) which can display some engine data is also unsupported with the manufacturer gone and bust …

That obviously is a high risk too and that is why only a FADEC or ECU built, supported and implemented by the two big ones or by another too big to fail company is the answer to that.

What would be really needed to create an incentive for this is a clear and open study what they would actually achieve in terms of fuel economy and engine health. My gut feeling on that is, seeing how many people still think the mixture is something for “experts” or who don’t use it due to bad instruction, it would certainly improve engine health. Likewise, seeing how much fuel flow reduces LOP and how many engines can safely be run on LOP yet people don’t do it out of irrational fears, it should be able to create a noteworthy reduction of fuel use already with that, not even taking into account what other innovation such as electric ignition e.t.c. could do.

But anyway, @Sebastian_H, what have been your experience with the said FADEC and so on? How does your engine behave as opposed to a standard IO-360? Do you see reduction in fuel consumption? I think it would be quite crucial to collect this information to see if a project would be feasible. If lots of people would be interested because there is something in it for them, such as lower fuel cost, increased range e.t.c., it should be possible to create a demand which might get one of the big companies to consider it.

Mooney_Driver wrote:

But anyway, @Sebastian_H, what have been your experience with the said FADEC and so on? How does your engine behave as opposed to a standard IO-360?

Take my experience with our particular FADEC with a grain of salt as I actually have not too much comparison data – I trained on the equally FADECed Diesel Robins, and the only “classical” Lycoming I flew with was in our aerobatic Robin R2160 trainer, maybe not more than 10h.

Our engine starts quickly warm or cold, I haven’t experienced any issues or arcane starting rituals. Fuel consumption is what it is as I have no influence on it, and it seems to fall within the expected performance vs. fuel data gleaned from the discussions on vansairforce.com (which include a mix of carburetted, fuel injected, EI, EFI, FADEC engines). It seems that on 8k-9k ft with wide-open throttle and power set with the prop lever, the FADEC tends to run more rich than expected by the power percentage set, but without having done some actual hard-numbers testing, it’s something I want to follow up (a first idea that a WOT switch present on the throttle body would trigger is not the case, the switch is unconnected to the FADEC).

As Ibra points out, his Mooney with the same engine runs very similar fuel flow vs. performance figures, so I wonder where I lose the advantage of flying something a bit lighter.

The drawback of FADEC are the usual computer-related issues of “What the frell is it doing now?” and “Dear gods, please don’t take away my electrons”. The first issue is in our case an spurious FADEC caution every now and then that either disappears after a second or disappears after resetting the B FADEC controller; since the engine neither feels strange nor shows any transient performance numbers, I have the impression it relates to an intermittent issue with one of the sensors, similar to the issues that plague the Continental Diesel FADECs. As there’s no usable data logging of the FADECs, investigating this issue is not easy unfortunately.

The second issue is of course the graver one and has led to a quadruple-redundant design of the electric system; there’s a main and auxiliary bus which are completely separate, both with an alternator and battery, and the FADECs take power from both buses (diode separated internally I assume); The main bus has the usual 55A alternator in front and a PC680 battery, the auxiliary bus has a vacuum-pad mounted 20A alternator and PC310 battery and only feeds the EIS and FADEC.

Mooney_Driver wrote:

If lots of people would be interested because there is something in it for them, such as lower fuel cost, increased range e.t.c., it should be possible to create a demand which might get one of the big companies to consider it.

I would hazard a guess that it would not make a big difference: Pilots that are actually invested and interested in flying will utilise the red lever and run a less than full-rich cruise setting anyway, so the gains from a FADEC can’t be much (and are IMHO outweighed by the massive increase in complexity and reliance on single-source procurement). Even a crude approach to pull back until the engine roughens and then go forward a bit until smooth (while keeping an eye on CHT and EGT if available) would probably provide 80% to 90% of any FADEC cruise gain, so you’re left with (maybe) easier starting.

Maybe in the homebuilt sector things are a bit easier since retrofitting an SDS EFI or SureFly is a technical and not bureaucratical issue; still, having one of the self-powered ignitions (magneto, P-MAG) is probably easier and more future-proof system: I could get rid of the heavy main alternator which would solve the belt replacement issues, would save some weight, and decrease complexity – the Chapman approach to cars in a nutshell, and I adored my Lotus :)

[Edit: The Aerosance system was bought by Continental AFAIK, and they stopped further development or support, so not even a big player at the time saw a good market opportunity]

Addendum since I forgot: I actually ran a quick-and-dirty test for a few power settings last week, and while I had less time to get a settled fuel flow result due to the airspace and clouds, I got for our FADEC IO-360 RV-7 the following data (all at 5200ft, 4 degC OAT):

• 20" MAP, 2000 RPM, 47%, 126 KIAS, 135 KTAS, 20 l/h
• 22" MAP, 2200 RPM, 60%, 135 KIAS, 143 KTAS, 31 l/h
• 23" MAP, 2300 RPM, 67%, 140 KIAS, 150 KTAS, 34 l/h
• 24" MAP, 2400 RPM, 75%, 145 KIAS, 156 KTAS, 41 l/h

Aaand back to the climate change discussion, I wonder why the Fischer-Tropsch process is not touted more as an intermediate vehicle to move away from fossil fuels? I would be happy to see a few more nuclear power stations and wind parks, utilise the surplus power to synthesise fuel, and test the whole thing on a smaller starter market such as our end of GA. I know that for the certified crowd it will be difficult paper-wise, but all the microlights and homebuilts could run on Fischer-Tropsch-created UL91/96, and while a drop in the bucket of energy consumption, could take away the Green party’s envy argumentation clad in environmental guise.

Sebastian_H wrote:

Addendum since I forgot: I actually ran a quick-and-dirty test for a few power settings last week, and while I had less time to get a settled fuel flow result due to the airspace and clouds, I got for our FADEC IO-360 RV-7 the following data (all at 5200ft, 4 degC OAT):

20" MAP, 2000 RPM, 47%, 126 KIAS, 135 KTAS, 20 l/h
22" MAP, 2200 RPM, 60%, 135 KIAS, 143 KTAS, 31 l/h
23" MAP, 2300 RPM, 67%, 140 KIAS, 150 KTAS, 34 l/h
24" MAP, 2400 RPM, 75%, 145 KIAS, 156 KTAS, 41 l/h

Wow, that certainly shows the diminishing returns situation.

From the top to the bottom of that table you burn more than twice the fuel for only a 15% increase in speed. If I had that aircraft then I think 20/20 would be my preference for cruising, perhaps 22/22 if I was in a hurry.

Graham wrote:

From the top to the bottom of that table you burn more than twice the fuel for only a 15% increase in speed. If I had that aircraft then I think 20/20 would be my preference for cruising, perhaps 22/22 if I was in a hurry.

Take the data with some caution as our particular FADEC needs a few minutes to stabilise fuel flow after power changes (also the speed data for the 20/2000 setting seems a bit off, it should give more around 105-110KTAS and is probably an artifact or due to an uncorrected descent), time I could not spend that day on that position. But yes, I usually plan with 22"/2200/30/150KTAS@8000 with the 20/2000 settting being used for sightseeing etc.

In the end, I have no good comprehensive power settings data for our plane, the POH has the data for 55%, 65%, and 75% power, nothing else. Once I figured out a plan how to do systematic testing (starting from AC 90-89B), I will probably spend a day or so in Germany where the airspace is sane and do some runs to get stabilised data for the lower levels, my usual cruising altitudes, and some higher-altitudes at different combinations of RPM and MAP.

This seems feasible. You have to take into account however that the FADEC system will automatically set Lean or Rich of peak settings. Presumably it will get quite rich at 75% to cool the engine.

Getting back to the climate change discussion in a broader sense, have a look at this from my favorite science commentator..

A bit of a shock to me I have to admit. I thought we were creeping towards “energy out = energy in” and that ITER would tip the scale. Far from it, it seems. Huge difference between Qtot and Qplasma as you will see. Well, it’s pretty normal that they have been able to fool me and the general public, but once more it shows that our politicians are also easy to deceive, in spite of them certainly having critical experts at their disposal. Looks like a really successful conspiracy ;)

In the mind of an entrepreneur, one would seriously have to consider pulling the plug, taking the loss and redirect these billions to other renewables research, unless these people in their white gowns can come up with a plausible story that Qtot greater than 1 is an attainable goal before the whole solar system implodes anyway. Maybe they can’t and it’s time getting on with fission, if only as a bridge. These Thorium reactors seem pretty safe to me! Let’s forget this silly definition issue that fission by definition is not renewable because it uses a resource. A very abundant resource to start with. And the waste issue is manageable.