My floscan 201B is installed with a Rotax 912uls & FlightDek D180. This is a new installation and the aeroplane is in test flying. The K value on the tag is 16-2927 and the sensor setup has been entered as 29270. Today's testflight of 2hrs 40mins used 32 litres of fuel but throughout the Dynon Flightdek display showed between 19 and 26Liters per Hour consumption. The actual consumption was around 12 lph. I have tried upping the K value to as high as 32000 and whilst there is some improvement the LPH still appears too high. The floscan is instaleld downstream of the mechanical & electric fuel pumps. After leaving the flosca the fule travels slightly uphill. Any ideas please? Thanks Nick
Rotax 912ULS & Floscan 201b
- Thread starter nhodgson
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Well, various factors can influence the turbulence in the fuel line, which can in turn influence the K-factor needed to get an accurate fuel flow reading. I would go as high as you need to, period, and see if that solves it.
Also, if your 912 has a return line as they're going to start specifying for the ASTM motors - we do not currently have a solution that doesn't require two flow sensors and a matronics box to subtract the return from the intake (though we're looking into it).
Also, if your 912 has a return line as they're going to start specifying for the ASTM motors - we do not currently have a solution that doesn't require two flow sensors and a matronics box to subtract the return from the intake (though we're looking into it).
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A touch more background on the issue - we only have one input on our system capable with dealing with the flow sensors, hence our inability to directly work with two flow sensors. We're working with folks to see if there are any tricks that we can employ in software (ie - if the return flow is fairly constant, we could account for that algorithmically). In the interim, http://www.matronics.com/fuelchec/RFC/index.htm is a box that can take the inputs from two sensors and subtract them out to make it look like one. Note that if you already have one of our sensors, you'll only need the computer box itself and a second sensor, and not their display head (which is itself a fuel computer).
Thomas_Schaad
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Guys,
On the 912S it can be installed with one flow scan only. I do have it and it works great. The thing is, that you need to order a special fuel divider, which will incoporate a loop with the flowscan the way it won't be obstructed by the return line. Rotax has this part and it can be ordered. It is part number 10143 and can be purchased for example at
http://www.franz-aircraft.de/Rotax/4-takt-zub.htm
or your local Rotax dealer. Hope it helps,
Kind regards
Thomas
On the 912S it can be installed with one flow scan only. I do have it and it works great. The thing is, that you need to order a special fuel divider, which will incoporate a loop with the flowscan the way it won't be obstructed by the return line. Rotax has this part and it can be ordered. It is part number 10143 and can be purchased for example at
http://www.franz-aircraft.de/Rotax/4-takt-zub.htm
or your local Rotax dealer. Hope it helps,
Kind regards
Thomas
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- Mar 23, 2005
- Messages
- 13,226
Just FYI - on American Light Sport Aircraft, we hear that Rotax is going to start REQUIRING the return line. As this is part of the ASTM-compliant engine specs, it won't be able to be changed after installation without Rotax's and your LSA manufacturer's specific permission.