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Hi All. I bought the bird in February, but getting it 800 miles to its new home, when you're not so good at landing a Sonex, can be problematic and costly. It's a legacy model built in 2012, with a Corvair engine. Anyways, after some serious tribulation, it's at its new home at Columbia Gorge Regional, in Dallesport, WA. On the delivery flight the Enigma EFIS bit the dust, and Matt at MGL kindly sent me a loaner to get me home. with the new EFIS, I had no visibility of fuel level, so made shorter hops, but ultimately decided to measure the tank's volume and re-calibrate the fuel level sender. We have all been told that the tank holds 16 gallons, and maybe almost 17. Now my bird's a taildragger, so the filler neck is the tank's high point. Using a 1-gallon pipette from the feed store, and carefully removing and measuring fuel, I measured the tank's volume at a whopping 17.5 gallons! Knowing this, I don't get why one would cite 16 gallons as the tank's capacity. There's no unusable fuel. Sure, one wants to be conservative about this, etc. etc. but really? Does this depend on how tight the metal support straps are?

So I'm currently wrestling with the Enigma (seemingly aptly named). Hopefully there are lots of folks who have been in my shoes. I may cry out for help from time to time!
Tailwinds, all.
Art

Hi Art,

Nice pick up! Seconding what you’ve found, my tank (purchased in 2014) holds almost 18 gallons.

Hope you sort things out and have a solid bird.

JF

Hi Art, I think the tanks might vary a bit. The most I have ever been able to fit in mine by filling right to the brim is 61 litres, or 16.1 gallons.

Peter

I am writing this from work so it is a quick reply. Do you have an above cowl vent or below cowl vent? If below, fill the tank full then lift the tail to cruise level. Mine will drain a full gallon of fuel thru the vent.

Ken W
Sonex 959

Hi Art,

Congratulations on the new Sonex. Hope you have fun with it.

I used an Enigma in my XENOS for five years, and I now use an iEFIS Explorer in my OneX. The Enigma was a great system. If the seller didn’t give you the installation manual here is a link to the on-line version: http://mglavionics.co.za/Docs/Enigma-Odyssey%20installation.pdf It appears the actual Enigma user manual no longer exists on the web, but if you need a copy let me know and I’ll email the PDF to you. The manuals are accurate but not very well written. Better than nothing.

One little used feature of MGL’s EFIS series is the black box data recorder. There is a great application that can be used to read that data. For a demo video visit https://youtu.be/82WYZXPpCoc

Good luck with your new plane!

KMWoodie makes a good point. My vent is tall and faces the wind. So far I have never had a leak out of it. I was contemplating bending it over and connecting to a hose to spare the windscreen the indignity of a fuel splash. It was sobering to learn of the siphon effect, though! For now it stays as-is, since I don't fly aerobatics (yet).
On the Enigma: I have downloaded the user manual, but it lacks specificity in places. I will grab the installation manual from Michael, above. Thanks!
Art

I haven't found documentation on how the MGL iEFIS detects the beginning and ending of a flight. My buddy just started testing a new build and the .REC file seems to be empty. I have also tried using the simulator with no success. The file is there but when I tried to open with the MGL EFIS data tool no flights appear. Found the Data recording setup menu and have data recording enabled. Must be another step ?

jrs wrote:I haven't found documentation on how the MGL iEFIS detects the beginning and ending of a flight. My buddy just started testing a new build and the .REC file seems to be empty. I have also tried using the simulator with no success. The file is there but when I tried to open with the MGL EFIS data tool no flights appear. Found the Data recording setup menu and have data recording enabled. Must be another step ?

There is another step, I can't recall where to find the menu right now, but you can set minimum RPM/Airspeed to initiate/stop data recording. I had this issue as well and finally found the menu option, RPM was set to 5000 instead of the 500 I intended so it never recorded.

Thanks that was the clue I needed..
Under system setup menu -> system operation setup -> automatic flight detect.

jrs wrote:Thanks that was the clue I needed..
Under system setup menu -> system operation setup -> automatic flight detect.

I have my MGL data recording set to manual. So before I take off I need to select 'Menu' 'Start Flight'. (It's on my checklist.) Some flight analysis routines don't work well unless the entire take off roll is included in the data file. For example: https://www.youtube.com/watch?v=9mpSuvhGlC4&feature=youtu.be