Backcountry Pilot

[Zzz]

There are a few on the market:

Precision Airmotive: They make the Silverhawk mechanical FI and the Eagle electronic EFI/EMS. No return fuel lines required.
Airflow Performance: They make a mechanical FI. Return line required.
FlyEFII/Protek: They make a fully electronic injection with FADEC. Return lines required.

I don't like the idea of having return lines. Seems complex. I also like the idea of an engine-driven fuel pump vs electric. I'd be interested to hear some stats on reliability of electric vs engine-driven fuel pumps though.

Anyone have experience with any of these?

[fly offline]

I've got a couple Airflow a Performance FI systems on my airplanes. I'm very happy with them. I've got an FM 200 on my IO-540 B2B5 and a EX-5 (modified Bendix RSA-5) on my IO-320. Neither has a fuel return line. You might want to give them a call. They will require a mechanical (engine driven) fuel pump, and a electric or mechanical (wobble) boost pump. Give Don a call at Airflow Performance a call if you have any questions about their systems.

[Battson offline]

I also like the idea of an engine-driven fuel pump vs electric. I'd be interested to hear some stats on reliability of electric vs engine-driven fuel pumps though.

I am sure you would have two fuel pumps in any injected system? A primary and a back-up.
With the mechanical injection, Bendix in my case, I have one of each. Mechanical and electric.

I know the diaphragms can fail with the mechanical pumps.

[denalipilot offline]

Fly's setup sounds like my IO-360M1B setup. No return line or header tank. An always-on mechanical pump, and an electric pump for engine start and critical phases of flight, plus backup for the mechanical pump.
You hear lots about the even operating temps of injection. I'm no expert, but I understand it has as much to do with good baffling. If you have both working for you though, I think you will like the results. A friend was looking at my 4-point engine analyzer, and commented that if hers looked that even, she'd assume the instrument was broken.
Just figure out your hot-start technique, and you'll be loving life.

[Zzz]

As I understand the Airflow Performance setup, there's a return line only to the fuel valve, not all the way to the tank(s). I should prob solve the mystery by calling the guy.

Battson: Noted on the redundancy.

[175 magnum offline]

On Bearhawk #357 we used the SDS system for complete engine management on the Landrover motor and no problems in 1500+ hrs. Darcy has now switched to an updated version of the SDS because it offers more options with regards to recording and trimming. I ran the SDS system on my Subaru powered hovercraft for nearly 3000 hrs before I sold it. Zero problems and all had electric pumps with return lines. We used the return line system to keep the fuel cool.
The EFII uses all SDS components but it is designed specifically for air cooled aircraft engines.

[hotrod180 offline]

...........I don't like the idea of having return lines. Seems complex. I also like the idea of an engine-driven fuel pump vs electric. I'd be interested to hear some stats on reliability of electric vs engine-driven fuel pumps though. Anyone have experience with any of these?

FWIW I believe that the FAA's policy with certificated airplanes is that if you have an engine-driven fuel pump, you also have an electric boost pump for backup.
My C150/150TD had a Lyc 320-E2A engine, and in spite of it being a high-win with gravity fuel feed it had an engine-driven pump and an electric boost pump. The requirement for fuel pump(s) may have been a fuel-line-size issue.

[fly offline]

As I understand the Airflow Performance setup, there's a return line only to the fuel valve, not all the way to the tank(s). I should prob solve the mystery by calling the guy.

Battson: Noted on the redundancy.

The AFP purge valve is optional. I've got my planes set up like a Bendix system and do not use the purge valve so I have no fuel return lines whatsoever.

[hotrod180 offline]

Zane, as I recall you're planning a 540 Lyc for your BH. Why not an IO with the factory injection?

I find it interesting that while Ponk & a couple other outfits make a pretty good living from people wanting a carbureted version of the IO-520 Cont, here you are talking about adding after-market fuel injection ... and to an engine available from the factory with FI.

[Zzz]

Zane, as I recall you're planning a 540 Lyc for your BH. Why not an IO with the factory injection?

I find it interesting that while Ponk & a couple other outfits make a pretty good living from people wanting a carbureted version of the IO-520 Cont, here you are talking about adding after-market fuel injection ... and to an engine available from the factory with FI.

I probably should just buy a Skywagon.

[175 magnum offline]

Zzz
Even if you put an electronic injected and ignition controlled 540 in a 180 it still would not be as good as the Bearhawk. (hehe- flame suit ON)
In all honesty my ideal plane would be a 180 with a chevy LS3 motor package with the GM marine/international control box that allows you to use leaded gas. Swing a big MT prop and install a sportsman kit and big tires and it would getter done.
My 175 is getting this treatment but I will not have the adjustable stab and I have to work around the stepped firewall. The Cessna's are just easier to get my fat ass into than the Bearhawk.

[TangoFox offline]

There are a few on the market:

Precision Airmotive: They make the Silverhawk mechanical FI and the Eagle electronic EFI/EMS. No return fuel lines required.
Airflow Performance: They make a mechanical FI. Return line required.
FlyEFII/Protek: They make a fully electronic injection with FADEC. Return lines required.

I don't like the idea of having return lines. Seems complex. I also like the idea of an engine-driven fuel pump vs electric. I'd be interested to hear some stats on reliability of electric vs engine-driven fuel pumps though.

Anyone have experience with any of these?

I like the idea of return lines.
I don't know if they are totally necessary but it makes sense to keep the fuel cool and avoid vapor in the system.

I also like the idea of an engine driven pump with an electric boost for prime and emergency backup.


If your electrical system craps out your engine will still run!

[Pusher offline]

I also have the SDS ( http://sdsefi.com ) system. It is a great, reliable fuel injection and ignition system. My system has 2 electric fuel pumps, one primary, one backup and a backup battery in case of an alternator/main battery failure. One of the advantages of having a return line with a header/surge tank on a fuel injected engine is that if you have water in your fuel, the injection system return line fuel flow mixes the two and the chance of an engine failure due to water contaminated fuel is highly unlikely.

[Zzz]

Zane, as I recall you're planning a 540 Lyc for your BH. Why not an IO with the factory injection?

I find it interesting that while Ponk & a couple other outfits make a pretty good living from people wanting a carbureted version of the IO-520 Cont, here you are talking about adding after-market fuel injection ... and to an engine available from the factory with FI.

Eric, to answer your question seriously, I suppose that's an option. 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.

[Mister701 offline]

The recommendation from Rotax on the 912 series is that they have return lines. These of course are carbureted but the point is made that the return line never flows more fuel than the supply line. So, the return needn't go all the way back to the tanks with those issues; i.e. draw from the left and return to the right etc etc. Many simply return fuel through a T fitting to a point just ahead of the main shutoff valve.

I suspect that you are reluctant to have any fuel in the cockpit but an alternate plan is a small header tank. By that I mean something like this: http://www.ebay.com/itm/8X30-Spun-Alumi ... d6&vxp=mtr These guys will make you anything you want. I'm considering something like that behind the seat in the 701.

[Zzz]

Yep, no header tank desired.

[jaudette offline]

+1 for factory FI...

I think you'll have trouble with hot-starts without a means of cooling the lines/fuel... I would go with a return line to solve that problem. It's really not that complex and solving the problem after the build will be a pain in the ass...

Jim

[Zzz]

I was under the impression that the factory injection of the era of parallel valve 540s (Bendix RSA) servo does not have a return line. Of course for certified aircraft that can be type-specific depending on the engineers.

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?

[8GCBC offline]

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.

[M6RV6 offline]

I have the Racetech Inc. 4F injection and ignition system in hand, just have to get it installed on the 360 going in the Glastar.
K.I.S.S.
Cleanest system I could find. Modern electronics and should be able to burn anything called gasoline.
I am adding a Garret Turbo to the system for normalizing to 14,000'
GT