Auto grade fuel flow meter

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Barber
Posts: 24
Joined: Sat Oct 18, 2008 6:15 pm

Auto grade fuel flow meter

Post by Barber » Tue Apr 12, 2022 9:03 pm

Hi
Has anyone come across a fuel flow system which they have added to a permit aircraft (with LAA approval) that is not of aviation origin. I am aware of the various systems available for around;£500 (turbine meter plus remote readout) from various aviation suppliers but hoped some auto grade systems might be out there. I haven’t been able to find anything after a night of googling.

Thanks
Tony
Tony Barber
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ROB. THOMASSON
Posts: 129
Joined: Mon May 14, 2012 5:36 pm

Re: Auto grade fuel flow meter

Post by ROB. THOMASSON » Mon May 09, 2022 8:11 am

Take care. I've known automotive flow meters fail and block the fuel flow. The latest increase in ethanol can be detrimental to some plastics
027506

Rob Swain
Posts: 393
Joined: Tue Jan 08, 2008 2:11 pm

Re: Auto grade fuel flow meter

Post by Rob Swain » Thu Jul 28, 2022 11:15 am

Tony.
I understand an applaud your hunt for automotive engine monitoring systems (EMS) for aircraft use.

However...

Just wondering where you are at regarding other engine monitoring and whether you have considered the 'bigger picture'.

If your current engine monitoring is just RPM, oil T & P and fuel level gauges then rather than homing in on just adding fuel flow to an existing setup maybe consider one of the newer EMS offerings from the likes of AVMAP (for Rotax engines), Kanardia or MGL. An 'affordable' EMS will cost a bit more than maybe you were thinking of spending right now (MGL starts at £330 for the Blaze instrument), but for many of these systems you can add as many or as few senders as you like and add more later as additional pennies become available. An EMS will monitor bus voltage straight out of the box, then after your desire for fuel flow then I would consider CHT and EGT as useful starting points, replacing RPM, Oil T & P as and when you want (if your existing senders aren't compatible) and then moving on to the more unusual ones like OAT, carb temp, current etc.
In many EMSs you can add additional micro-switches to create alarms for canopy shuts etc.
All the above instrumentation will almost certainly weigh less than a basic set of engine instruments.

Additional features with an EMS are the ability to download / analyse / keep engine telemetry data. This can be surprisingly useful.
All these systems will continuously monitor your engine parameters and issue a visual alarm and sometimes an audible one should something be going awry. I refuse to believe a pilot can effectively monitor more than about 4 engine instruments in addition to actually flying the plane.

I have no connection with any of the above mentioned companies.
I have a Dynon D120 in my plane with a lot of monitoring. It's brilliant. It is also now old technology and quite expensive. If I was building something new or updating an existing aircraft then I would be considering the above options. If I was running a plane on a small budget I would definitely go with one of the above.

One more small thing as an aside...
Fuel flow. It is a useful figure but not the be-all-and-end-all. In my RV the EMS is also tied into the GPS296 which allows display of an MPG figure. I use the fuel flow and EGT indications when leaning. However, I have found that a higher throttle setting, higher speed and a bit more fuel flow gives better MPG. When you throttle everything back to achieve min fuel flow you have to increase AoA which increases drag!

Just my thoughts...
Rob Swain
If the good Lord had intended man to fly, He would have given him more money.

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