fuel flow information

rv8ch · #1 03-09-2017, 01:34 PM

I have a FF sensor but I'm considering not installing it. While I think I would like the information it would provide, I'm struggling with installing something in my fuel system that is not really needed. It just seems like another device that could fail or cause the big fan to stop turning.

My question is how much do you guys actually use your FF information? Is it really worth installing a FF sensor? It seems like after a few flights, you'd know your FF for a particular temperature/altitude/RPM/MP combination and after that it would not add a lot of value.

I've never flown an aircraft with FF info, so I'm sure I'm missing some amazing feature.

Thanks for any tips.

Aggie78 · #2 03-09-2017, 01:49 PM

Quote:

Originally Posted by rv8ch

I have a FF sensor but I'm considering not installing it. While I think I would like the information it would provide, I'm struggling with installing something in my fuel system that is not really needed. It just seems like another device that could fail or cause the big fan to stop turning.

My question is how much do you guys actually use your FF information? Is it really worth installing a FF sensor? It seems like after a few flights, you'd know your FF for a particular temperature/altitude/RPM/MP combination and after that it would not add a lot of value.

I've never flown an aircraft with FF info, so I'm sure I'm missing some amazing feature.

Thanks for any tips.

My FF indicator (and resulting data on fuel used for each flight) is extremely accurate...especially as I've gathered the data to refine it's settings for even more precision. I can pretty much predict how much gas I'm going to have to pump to the nearest quart...sometimes, even more precisely than that.

My fuel gauges, on the other hand...well, not so much.

While you can get by without it, I think if you take the leap and install it, you'll find the data it provides very valuable.

My dos centavos,

Rob

Carl Froehlich · #3 03-09-2017, 01:49 PM

I consider Fuel Flow a must have.

In addition to a much more accurate track of fuel remaining, it is required tool for things like balancing cylinder injector nozzles. It is also the way to standardize LOP operations.

Add it and build on.

Carl

airguy · #4 03-09-2017, 01:57 PM

I've got one, and I wouldn't do without it. The one time I thought it was failed, it was actually just a bad wire connection.

What type of indicator is it? The device should be fail-safe intrinsically, meaning that even if the moving parts lock up it still passes fuel without restriction and cannot cause a fuel stoppage. Assuming, of course, you don't use RTV to seal your line connections...

JonJay · #5 03-09-2017, 02:07 PM

Assuming you have a fuel computer/totalizer, as a minimum, and engine monitoring equipment. FF by itself is not very useful.
Today's engine monitoring equipment also ties to your GPS for automatic estimates of required fuel to destination, reserves, etc... which can not be done without fuel flow data.
Makes enroute flight planning/changes much easier.

Otherwise, a power chart, a watch, and a whiz wheel. Don't need no stink'in computers.

JohnInReno · #6 03-09-2017, 02:10 PM

The fuel flow information is "instant" and I use it regularly for engine operations. I know that my IO-320 peaks at 7.5 gals/hr and that 100+ ROP requires at least 9.6 gals/hr. Quick and dirty safe operation LOP is 7gals/hr or less and ROP is 9.6 or more. Also, the EMS automatically calculates range and time remaining from the FF info.

You can use conservative planning numbers and compare them to "pump to pump" actual consumption for refinement. If all of your "missions" are similar, then that might be all that you need.

It is true that you are adding a single point of failure to the fuel system. I believe we lost an RV10 due to improper installation of the FF sensor.

My experience only. Hope this helps.

Aggie78 · #7 03-09-2017, 02:21 PM

https://www.ntsb.gov/_layouts/ntsb.a...31X15032&key=1

bruceh · #8 03-09-2017, 02:55 PM

Fuel flow is essential for making sure you don't end up as a statistic (ie, running out of gas). As noted above, having the EFIS calculate all of your remaining range and time in real time as you play with the throttle and mixture is wonderful. This last weekend on our return from Harris Ranch, we were going to aim for Cable to get cheap gas. We could have made it (barely), but looking at the numbers I made the correct decision to divert to Shafter and put 10 gallons in for my comfort and safety. When we got to Cable it took 21 more gallons. I figure I would have made it there with only about 4 gallons left, which is NOT enough (better to have 6+ gallons which is an hour reserve).

Bob Martin · #9 03-09-2017, 03:41 PM

Hate to admit this but more than once the FF display reminded me to lean!
Agree with other posters....now that I have it, love it, do not want to be without it. But certainly not required, but either is underwear!

JonJay · #10 03-09-2017, 04:03 PM

Quote:

Originally Posted by Bob Martin

Hate to admit this but more than once the FF display reminded me to lean!
Agree with other posters....now that I have it, love it, do not want to be without it. But certainly not required, but either is underwear!

Guilty (the leaning part not the underwear part)