8GCBC wrote:Most folks I know who used experimental ignition, FI, and such, have had horrendous crashes and close calls. Here in Hawaii and Oregon.

There are primary divisions I see in building:

(1) Exprimentation, the pure love of building something better. Not really to go flying as much as providing scientific research to the community. EAA relishes this type of builder for example.

(2) Build it fast and with proven (mostly) certified engines and avionics ( not conclusive, but generally). Vans actually encougres building with a certified engine ( or a reasonable facsimile ).

(3) Building requires to much time indoors, to much time and money for the skill level required. Said builder quits and purchases a flying aircraft. Me for exampl.

If I had unlimited time and money I would investigate all types (listed above) However, option # (1) I would do in the Neveda flat lands. Option # (2) is for Western Oregon, which in my book ain't a good place to test aircraft. Option (3) is where I ended up. It simply made sense for me.

Zane, you are flying in an area which is not ideal if something does NOT work out in the air. "Be careful of the better options..." quote from Van.

+1... Great comments.... We just had a fatal north of our airport because of a goofy injection system. I kind of view it as an unnecessary risk, relative to the simplicity of just getting a factory FI engine...

But WTFDIK...

Thanks for the input everyone.

Zzz wrote:Any more tales of first hand experience with the experimental-only injection systems I originally posted about from people who have built aircraft using them?

My first hand experience was out fishing listening on channel 16 (common calling frequency for all marine craft and USCG air)...

I listened to a USCG helo homing HNL Center's LAT/LON of a RV-8 which ditched 20 miles from Kauai. The pilot was a first officer on HAWAIIAN airlines and a great pilot. He said, later at my hangar, the engine died. I almost bought that RV-8 instead of him. But, a little angel told me NO!

The aircraft was well known to me and I was a €u#t hair away from buying her. The engine was heavily modified with better than certified parts! But, again something told me "do not fly it"!

Racetech inc./ Simple Digital Systems and EFii are all basically the same systems. Between the aircraft and hovercraft I have almost 4500 hrs flying behind that stuff and Zero problems. Do I think electronic injection and ignition are safe, you bet I do. Do I think carbs and magnetos are safe, not so much any more because they start to deteriate the minute you begin to use them.
You should do LOTS of home work before you make your decision.

175 magnum wrote:Racetech inc./ Simple Digital Systems and EFii are all basically the same systems. Between the aircraft and hovercraft I have almost 4500 hrs flying behind that stuff and Zero problems. Do I think electronic injection and ignition are safe, you bet I do. Do I think carbs and magnetos are safe, not so much any more because they start to deteriate the minute you begin to use them.
You should do LOTS of home work before you make your decision.

Thanks. That's exactly what I'm doing.

I'm going to PM you to talk specifics on your plumbing and setup.

Also thanks to user fly on the AFP endorsement. Another guy on the Bearhawk forum said he was happy with with his Silverhawk too, as an example of another system. Lots of choices.

What I've found is that the vans air force site seems to have the largest wealth of detailed information on aftermarket 540 setups as they have a sampling of builders who've used each system, and these are apple to pears type comparisons as each system is different on the scale of pure mechanical to pure electronic. Lots of reading to be done.

Thanks.

Zzz wrote: .....As with everything in the experimental world, advances are routinely made without the impediment of certification. If the factory Lycoming injection system is superior and affordable, that's certainly an option. I think the experimental copies of the factory mechanical (Bendix design) are probably cheaper and just as good. I'm interested in embracing modern electronics for their advantages but not as the expense of reliability. Reasonable redundancy of engine driven and electric seems acceptable.

Zane, as you know, I'm a dinosaur. I don't really like high-tech stuff, and (maybe that's why!) I don't seem to have good results using it. That's why I'm a magneto/carburetor kind of guy. A guy at my airport built a GlasStar with some sort of FADEC set-up, and seemed (to me) to have nothing but trouble with it. Another guy had trouble with his electronic ignition. Another guy had trouble with a delaminating composite prop. Yes, carbs mags & aluminum props can have problems, but they're usually pretty simple to figure out and to fix.

Just call me old-fashioned, I guess. Then again bolt-action rifles (or even more so, lever guns) are old fashioned, but they still get the job done and are in fact the firearm of choice for most hunting. Think I'll stick with the tried and true and leave the experimental aviating to others.

I hear ya, and that would have been a good answer if I had originally asked what everyone thought of experimental electronic systems vs old certified mechanical, but I'm looking for info on these specific products.

Point taken.

Most, if not all engine failures of the above mentioned commercially available EFI systems are not caused by the system itself but very poor installation practices by the builder. Poor wire splices, connectors and wire routing done by the builder come to mind as well as, not following manufacturers instructions and/or modifying the standard programming parameters wrong (e.g. timing and fuel tables) which can potentially destroy an engine. I have only experience with the SDS system and you can change any imaginable parameter via the programmer. So it is important you know what you are doing, especially when trying to optimize the system for maximum performance and efficiency. If you don't read the manuals properly, its easy to set parameters which give you awesome performance until the engine eats itself up. (e.g. timing retard, running to lean at certain rpm settings etc). The only real drawback of a system like this, if you can call it that, is that you need electrical power for the engine to run. However, having an alternator, main and backup battery the chances of an engine failure on an engine with a properly installed commercial EFI system are not greater then an old technology, magneto driven certified engine. In the unlikely event that your alternator and main battery fail at the same time, the engine will still run for at least 20 minutes (on my aircraft) on the backup battery. Why do you guys think there is a need for 2 spark plugs per cylinder on these old absolute engines? Magnetos can fail, spark plugs foul, timing/ignition and injection are inefficient. Ever wondered why most certified fuel injected aircraft engines have warm start problems? The technology of the modern EFI/EMU systems comes from the automobile industry, a proven technology by probably millions if not billions of engine hours. I know someone who has worked in the automobile industry testing new engines for reliability. They simulate real life conditions in the test cell and at the end of testing try to destroy the engine removing the coolant, then the oil. Some of these engines continue to run for many many hours before they fail. I have witnessed certified aircraft engines fail with a dual magneto failure, carb icing and incidents due to spark fouling. There is no guarantee that your certified engine will not fail. Just because this technology is at the moment mainly available in the experimental aviation world doesn't make it less safe. The real problem in the experimental world is an individual builders quality control. I really like the benefits of having a more efficient engine with more power at significant less fuel burn then a conventional engine. Multiport injection systems like this are now even available for engines like the Rotax 912 increasing power and reducing fuel burn. http://www.sdsefi.com/rotax3.htm

Maybe a bit off point, but I seem to recall seeing ads in Sport Aviation years ago for a "throttle body injector" set-up, by Ellison maybe? Don't see it in the most current issue I have on hand, maybe out of business. Was tha ta true fuel injector system, or just a weird sort of carburetor?

hotrod180 wrote:Maybe a bit off point, but I seem to recall seeing ads in Sport Aviation years ago for a "throttle body injector" set-up, by Ellison maybe? Don't see it in the most current issue I have on hand, maybe out of business. Was tha ta true fuel injector system, or just a weird sort of carburetor?

Weird sort of carburetor. Still, they are out there and selling stock on hand only plus parts support according to rumor. Rotec makes a similar unit that the Pitts crowd uses along with the older Ellison.

http://www.ellison-fluid-systems.com

But......off topic. Sorry.

How do the FLY EFII and SDS companies relate or compare? It appears to me that FLY EFII is reselling SDS equipment as a package?

I'm curious about these systems now because of the several endorsements of them here, as well as the ability to ease hot starts and run auto gas effectively. They are the closest thing to FADEC that's available for an old Lycoming.

Question:
Do the Airflow Performance and old Bendix/RSA designs require the electric high-pressure fuel pump to be running at all times? Or is it merely a backup to the engine driven pump?

Edit: Answered my own question by reading the manual. The electric pump is considered a boost pump or a backup in-flight pump UNLESS it's a continuous-operation style pump as the Airflow Performance brand pumps are.

I'm researching this because it is possible to build a fuel injected system that runs without any electricity. On the other hand, the optimization and tunability of the all electronic SDS is appealing.

We used the silver hawk kit (purchased through Aircraft Spruce) to convert an installed O-540 to fuel injection - very happy, made a huge difference to be able to run LOP - cylinder temps now 350F+-, fuel consumption down a couple of gph. Key ability was being able to use primer ports for the injectors.

Zane,

When it comes time to replace the engine in the SQ2 I will be going to EFII. Here is where my thinking is currently:

1. I will install two EarthX batteries (still half the weight of a single Odyssey), wire them up so the alternator charges both but the plane only uses one. A simple throw of a toggle will switch the airplane to the other battery so in the event of an Alternator failure I have a longer run time.

2. I'll isolate the ignition/fuel system on its own master so in case I need to de-power the rest of the plane I can do so without affecting the ignition/fuel.

3. I'll have an auxiliary fuel pump.

4. I might install one PMag, but jury is still out on this.

That's where my thinking is currently.

The advantages of EFII are just too great for me to ignore. Much better fuel burn, much more efficient use of fuel, and cooler engine temperatures running LOP. Lighter weight, especially if I don't install the one PMag. And more horsepower to the prop since it won't be needed to turn mags (probably not perceptible though).

Agreed Phil. The variable advance of the ignition working in concert with the injection and sensors really makes for a robust system that allows you to run lower octane fuels without risk of knocking/detonation. It also makes starts much less of an issue.

So much to learn in order to do it right. For instance, I hadn't even thought about putting the fuel and ignition on a separate bus from the master. In the event of an electrical fault or fire, and you were lucky enough to not experience it on the fuel/ignition bus, it would be handy to have it isolated.

The one thing I'm confused on is the two-plugs per cylinder thing. SDS makes mention of it requiring a second ECU for redundancy, but what if you're just after the performance increase of dual spark? Redundancy though could be accomplished with a pmag or traditional magneto I guess. Not sure how that would work with the variable advance.

8GCBC wrote:Most folks I know who used experimental ignition, FI, and such, have had horrendous crashes and close calls. Here in Hawaii and Oregon.

There are primary divisions I see in building:

(1) Exprimentation, the pure love of building something better. Not really to go flying as much as providing scientific research to the community. EAA relishes this type of builder for example.

(2) Build it fast and with proven (mostly) certified engines and avionics ( not conclusive, but generally). Vans actually encougres building with a certified engine ( or a reasonable facsimile ).

(3) Building requires to much time indoors, to much time and money for the skill level required. Said builder quits and purchases a flying aircraft. Me for exampl.

If I had unlimited time and money I would investigate all types (listed above) However, option # (1) I would do in the Neveda flat lands. Option # (2) is for Western Oregon, which in my book ain't a good place to test aircraft. Option (3) is where I ended up. It simply made sense for me.

Zane, you are flying in an area which is not ideal if something does NOT work out in the air. "Be careful of the better options..." quote from Van.

Horsepuckey. There are a LOT of experimental aircraft flying around these days with electronic ignition and experimental fuel injection. I'd bet that a very high percentage of the RVs have one or both of those systems.

Ever hear of the Carbon Cub....which happens to be selling like hot cakes? Electronic ignition......

And, lots of other examples.

MTV

And, Z, for what it's worth, you definitely want a mechanical fuel pump and an electric pump. That pretty well covers all bases.

I once had an engine driven fuel pump fail in flight......and it was on a 40 mile overwater leg.....just about equidistant from both shores..

I like backups.

MTV

I just got off the phone with Robert Paisley at Fly EFII. This guy is an electrical engineer by trade, having worked in automotive and motorcycle electronics, and has been building these systems for 8 years. He built and flies a RV-7. He is very knowledgeable, at least in my assessment. I'm pretty easy to impress though.

Fly EFII uses the SDS electronic control unit, and builds everything else for the system themselves. Many of the who's-who in our little corner of the world are experimenting with these. It seems well baked enough to sell me.

Advantages:

- Performance mixture tuning is done using the actual air-fuel ratio, not exhaust gas. Using EGT for tuning is for systems where no other sensor/data is available, such as our traditional all-mechanical systems. Nothing wrong with that other than it's best guess vs real data. This system uses intake air temp, manifold pressure, RPM, and throttle position sensors to optimize.

- The variable advance ignition timing sets the advance to the optimum for every RPM. He said the smoothness of the engine is so pronounced it weirds some people out.

- I told him I was a bush plane guy and light weight was important. He said even with dual ECUs for redundancy, the fact that you are losing the heavy magnetos and carburetor, as well as being able to run the super light EarthX batteries, a typical net weight savings could be around 5-7 lbs.

- Injectors have a better atomization/diffusion pattern vs some of the more conventional ones available.


Considerations

- Return lines all the way to the fuel tanks. It is a continuous loop.

- Duplex fuel valve required

- No engine driven fuel pumps, all electric. They include a continuous run primary and a failover backup pump in a single housing.

- Primary and backup batteries

- Lots of wires.

- It's a hell of a lot more complex than a carb and magnetos, but reliability is equivalent if not better when setup correctly.

As for the return lines all the way back to the fuel tank, SDS actually recommends to have a header/surge tank. For my system I have a 3/4 gallon header/surge tank where the return line taps in. This has several advantages, if using an EFIS with a fuel flow sensor it also does not require a return sensor to get a proper reading, no duplex fuel valve required and another advantage if low on fuel in the main tanks and in an unusual attitude the fuel pump is protected from potentially sucking in air.

As for the 2 battery setup you also need a battery isolator and automatic charging relay, otherwise you will destroy the batteries over time. Obviously, you want to set your electric system up in a way where the alternator can power all systems and the #1 battery is for starter and the #2 battery runs the EFI system and the rest or vice versa. Battery 1 will be charged first by the automatic charging really and when full it will charge battery 2. In normal operations the 2 batteries are isolated and usually fully charged, while the alternator is providing all the power. When you lose your alternator you switch to emergency, which combines both batteries and will give you double AH. Switch all unessential electronic consumers off, either via individual switches or some sort of master like an avionics master and depending on battery capacity you have at least 20-30 minutes to find a landing spot. Another advantage is when you forgot to switch your master off in the bush and the batteries are isolated one battery is still full and when switching to emergency mode, both batteries are combined and you are able to start the aircraft.