Alternatives to standard fuel sight gauges

[N204jh]

I've searched the forum for a discussion on alternatives to the standard cub-like fuel tank sight gauges, but couldn't find anything. I saw on some other forums about using Belite Aircrafts fuel transducer, but they are out of business. I'm familiar with the variety of fuel tank gauges, i.e. capacitive, magnetic, but was hoping if anyone actually used (and likes) one of these other solutions.

I understand the nostalgia of using sight gauges and it's just so easy - look up and see the fuel levels on both tanks, but I also don't like another fuel source in the cabin during a crash. Especially in a large Bearhawk 5, the idea of having 2 additional sources of fuel spewing in the cabin is disconcerting. I think C206 with 6 people more than a Supercub or Patrol with 2 tandem seats.

Thoughts and ideas?

John

[jaredyates]

There are some options other than wing root sight gauges. But in any case you are still surrounded in the cabin by the four fuel lines made from soft aluminum. I mounted the sight gauges outboard of the fuselage, on the inboard side of the innermost wing rib, and find that to be an acceptable level of risk. I can't see any forces being imparted to the sight gauge that aren't also going to destroy the main fuel lines first. The wing could be totally separated from the fuselage without removing the sight gauge.
Cubs that I have flown have used a cork and wire in the fuselage tank that sits above the passenger's lap. Naturally that's not an option for us.

[SpruceForest]

No getting around fuel in the cabin per Jared's post, so my concerns are usability and reasonable accuracy. On our two Patrols, we opted for standard AS capacitive-type sensor due to compatibility with the fuel management and EFIS.

Since the first day of primary, I've taken off with a time to be back on the ground on my kneeboard or in grease pencil on the canopy or windscreen - worked for the last 50 years, so never got in the habit of trusting fuel gauges of any kind .

[Ryan Koeneke]

I haven't spent much time behind glass panels. Am I crazy for kitting out a full g3x touch system, 3 axis auto pilot, IFR setup and just having sight gauges without capacitive fuel gauges? I'm just about to finish up the first wing so I feel like there is still time to add them if it is silly not to have them. As I type this I kind of feel like I need to add them but any informed insight is appreciated.

[rodsmith]

I haven't spent much time behind glass panels. Am I crazy for kitting out a full g3x touch system, 3 axis auto pilot, IFR setup and just having sight gauges without capacitive fuel gauges? I'm just about to finish up the first wing so I feel like there is still time to add them if it is silly not to have them. As I type this I kind of feel like I need to add them but any informed insight is appreciated.

Your G3X setup is what I have. There is nothing more accurate than sight gauges. I really like being able to assess my fuel situation at a glance. Capacitive senders would be redundant but the great thing about experimental aviation is you can equip your plane the way you want. I understand the concern of fuel in the cockpit but as Jared pointed out you already have the 3/8" fuel lines. I placed restricters in the lines to the sight gauges where they exited the tanks. This also has the advantage of dampening the level in the gauge.

[jaredyates]

There is also the option to use fuel flow to calculate a fuel remaining on the screen, but that has its risks. I probably should have used more words similar to Rod's in that obviously one can build whatever plane they want. But there have been many times when I have gone down rabbit holes only to find out that I was moving farther away from the most elegant solution. I bring it up in case that might be what is happening here.

[N204jh]

Ryan Koeneke you better expressed my thoughts. Coming for the certified world, I was spoiled by the CiES digital fuel senders, which had another benefit of having the fuel tank level data in the G3X data log. I could then analyze the fuel usage from fuel flow as well as fuel tank level.

I'm also putting a full Garmin panel in my BH5, so I'm toying with a digital fuel sender. There's definitely a legacy of simplicity in the bush / tailwheel world that grew out of the Cub spirit. I grew up in the turboprop, high automation world and I'm really trying to adopt the culture of my backcountry hobby.

Even as I write this, I'm re-thinking my panel... I might just really start eliminating all of the glass I was adding and go back to simplicity - dual G5 with a GPS and autopilot. And ... keep the sight gauges.

[svyolo]

I have a GRT and tablet in my B model. Love it. I flew a Tailwind most of the way across the US in June. All steam but I brought my tablet and phone. TBH the tablet and phone are the Situational Awareness rock stars. I use my 10" EFIS as an engine monitor and steam replacement. I use it very little for navigation. I could easily get by with a G5 or two and tablet. I am retired airline/mil. All glass for the last 40 years.

I wanted electric fuel gauges as well, but am satisfied with my sight gauges. I doubt I will replace them.

[Battson]

It would be easy to encase the gauges is larger diameter flexible plastic tube which runs over the fittings and all the way back to the tank connections, top and bottom. That way, if the gauge has a break, at least the fuel leaks back into the wings.

But it sounds like hard work and probably not required. This is an old design, and I could not find any reports of an actual incident occurring like we're envisaging, due to an accident.

If the accident is so bad that the sight gauge gets smashed, right next to your head... you already have bigger problems. If the wing gets torn off, no worries, all the fuel is now somewhere behind you

[Bcone1381]

Ryan Koeneke

Even as I write this, I'm re-thinking my panel... I might just really start eliminating all of the glass I was adding and go back to simplicity - dual G5 with a GPS and autopilot. And ... keep the sight gauges.

Your not re-thinking you just keep thinking. Dont stop. I started out thinking like that and was just not at peace until I started removing bells and whistles. When I got to a single G5 I felt peace. I like precision hand flying a well rigged aircraft and do not want an autopilot. I like knobs and the Trig units are quality. Navigation is a hand held so when the industry standards change so can I. Iphone with foreflight (and ADSB in) is really primary navigation but I fear it will overheat.

BUild it the way you want. Cost out the hardware on that panel and let us know what it is. G5, CGR-30P, Garmin Aera 660, Trig com, and Trig Transpnder, Mangatometer and Temp Prob gives you winds aloft too. The Airspeed is a Winter guage for Gliders bought used on ebay.
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[DBeaulieu]

Bcone1381 Hey Brooks, what's the tubing on the lower dash for?

[Bcone1381]

I used some left over fuel line to fabricate a handy place to hold my pencil. I also can lean my iphone against the panel to view Foreflight.

[500AGL]

I would stick with glass, especially in a model five. The functionality for you as a pilot and the future resale almost demands that level of integration.

Relating to the fuel level questions we have a Cies sender that is designed for use in a Bearhawk main tank (not aux) and the factory will have mounts available in the next quarter to allow installation in the end wall of the main tank. These are G3X formatted only, as this is the platform we build on at the factory.

This can be used with or without the sight gauges.
Peter

[N204jh]

Thanks, Peter! How do I find out about the Bearhawk Cies senders? As I mentioned, I had them in my C182 and loved them. They were so accurate and fed nicely into the G3X.