VansAirForceForums  
Home > VansAirForceForums

- POSTING RULES
- Donate yearly (please).
- Advertise in here!

- Today's Posts | Insert Pics


Go Back   VAF Forums > Model Specific > RV-12
Register FAQ Members List Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
  #11  
Old 02-25-2017, 01:08 PM
AirHound AirHound is offline
 
Join Date: Oct 2006
Location: OFallon IL now, everywhere before
Posts: 158
Default

Quote:
Originally Posted by RFSchaller View Post
I use a length of translucent brake line as a dip tube. I calibrated it at 5, 10 and 20 gal. The 10-20 mark is not linear because at about 19.8 gal you start filling the filler neck which causes a faster rise in level.

I posted the dimensions previously. I will remove my tank soon to do the bulkhead split, window replacement and bell crank bracket mods. When I refill I plan on adding a 15 gal mark.

The tube is nice because you can coil it into a 1 gallon plastic ziplock for travel, but it quickly straightens out and is stiff enough to give reliable readings.
Rich, window replacement. Rear turtle deck?
__________________
Doug
Reply With Quote
  #12  
Old 02-26-2017, 12:11 AM
RFSchaller RFSchaller is offline
 
Join Date: Oct 2010
Location: Phoenix, AZ
Posts: 2,118
Default

Jean Pierre,

I found the non-cube effect affects the first 5 gallons most. The filler neck effects the last 5 gallons.

Rich
Reply With Quote
  #13  
Old 02-26-2017, 12:16 AM
RFSchaller RFSchaller is offline
 
Join Date: Oct 2010
Location: Phoenix, AZ
Posts: 2,118
Default

Doug,

Yeah my rear window was the original flat lexan not the new molded window. It was crazed to the point I could feel the cracks on the outside surface with my thumbnail. At almost $400 delivered to me I am expecting much better life. I got 5 years out of the first window. If it doesn't do better I'll be getting my third window from the aviation department at Home Depot! I'm keeping the first window in case I need a pattern.

Rich
Reply With Quote
  #14  
Old 02-27-2017, 08:15 AM
PilotBrent PilotBrent is offline
 
Join Date: Dec 2011
Location: Hackettstown, NJ
Posts: 417
Default

Quote:
Originally Posted by WingedFrog View Post

https://drive.google.com/file/d/0BzX...ew?usp=sharing

Keep this picture of the Moeller gauge dial with a Gallon scale with your Checklist:

https://drive.google.com/file/d/0BzX...ew?usp=sharing
Jean-Pierre, always wondered about calibrating the reliability of the Moeller gauge with the actual fuel in the tank. Based on your work, maybe a simple rule of thumb. "If the needle is above 1/2, the reading over estimates the actual fuel by about 1-2 gallons, below the 1/2 mark, its more close to the truth" Either way, I head for nearest runway when the needle is anywhere close to the 1/4 full mark. Thanks for doing/sharing this.
__________________
---------------
Brent Connelly
Hackettstown, NJ
RV-12, N913BC
Hobbs over 390 hours and on second set of main tires!
http://www.mykitlog.com/brent45

Check out & subscribe to my Youtube channel for latest RV-12 flying videos...
https://www.youtube.com/channel/UCxQ...Px2I7jmazGdLqg
Reply With Quote
  #15  
Old 02-27-2017, 10:24 AM
WingedFrog's Avatar
WingedFrog WingedFrog is offline
 
Join Date: Mar 2010
Location: Raleigh, NC
Posts: 854
Default

Quote:
Originally Posted by PilotBrent View Post
Jean-Pierre, always wondered about calibrating the reliability of the Moeller gauge with the actual fuel in the tank. Based on your work, maybe a simple rule of thumb. "If the needle is above 1/2, the reading over estimates the actual fuel by about 1-2 gallons, below the 1/2 mark, its more close to the truth" Either way, I head for nearest runway when the needle is anywhere close to the 1/4 full mark. Thanks for doing/sharing this.
Frankly, Brent I rely little on the Moeller reading, except to find if I made an error or if there is anything wrong with the other sensors/measurements.
We have three standard ways to evaluate the fuel tank level: computer flow, in-tank sensor displayed by Skyview and Moeller gauge. None is very precise and/or that reliable. It is why I loved the "never lying" windows and why I had to find a substitute with the dipstick. The calibration is easy for all but computer flow: start with an empty tank and go by 1, 2 or five gallons depending on how accurately you want to map the non linear shape of the tank as you mentioned. As for computer flow a lot has been written on this forum, I have nothing new to add. Of course above 14 or 15 gal., you are on your own as both floats hit the top of the tank way before it's full. Knowing exactly where you stand on the top 5 gallons is important for the computer flow derived fuel level, it's where the windows were useful and what you get back with the dipstick. After each flight I note the fuel levels provided by these 4 different sources which I recommend all RV-12 pilots to do: you will be amazed by the discrepancies you will find! Of course in case of discrepancy, the dipstick rules and it is also my source to enter in Skyview for the computer to use.
__________________

Builder's name: Jean-Pierre Bernoux
Sport Pilot
Kit # 120395 N124BX
Flying as of 9/11/2013

Builder's Blog:http://vieilleburette.blogspot.com/
EAA 1114
Reply With Quote
  #16  
Old 02-27-2017, 11:48 AM
DaleB's Avatar
DaleB DaleB is online now
 
Join Date: Sep 2012
Location: Omaha, NE (KMLE)
Posts: 1,724
Default

How precise do you really need to be?

I use the Moeller gauge mainly as a quick visual check pre-flight, to make sure the tank has what I think it has in it. If it's less than half full when I land, I fill it before flying again. When I fill it, I fill to the same point in teh filler neck so I know it's full. I've found the D180 indications -- both the float level once below 14 gallons, and the flow-calculated amount to be pretty accurate, within a couple tenths of a gallon.

Maybe I'm a little overly wussie about fuel reserves, but last weekend when I landed with about 4 gallons it was the lowest I'd ever gotten. I don't need to know the amount of fuel I'm carrying down to the ounce. I figure plus or minus a gallon or so is plenty accurate for the planning I do, and the D180 tracks it plus or minus about one or two tenths.
__________________
Dale
Omaha, NE
RV-12 # 222 N980KM "Screamin' Canary" (bought flying)
Fisher Celebrity (under construction)
Previous RV-7 project (sold)
-=VAF=- 2017 dues paid
Reply With Quote
  #17  
Old 02-27-2017, 02:04 PM
WingedFrog's Avatar
WingedFrog WingedFrog is offline
 
Join Date: Mar 2010
Location: Raleigh, NC
Posts: 854
Default

Quote:
Originally Posted by DaleB View Post
How precise do you really need to be?
.
You are probably right, Dale to question the need for accuracy for the type of flying we do in the RV-12. I have however found that since I have been involved in building an airplane and then flying it, even when unnecessary, precision does not hurt... plus, as the atheist said when caught praying: "you never know"...
__________________

Builder's name: Jean-Pierre Bernoux
Sport Pilot
Kit # 120395 N124BX
Flying as of 9/11/2013

Builder's Blog:http://vieilleburette.blogspot.com/
EAA 1114
Reply With Quote
  #18  
Old 02-27-2017, 02:14 PM
DaleB's Avatar
DaleB DaleB is online now
 
Join Date: Sep 2012
Location: Omaha, NE (KMLE)
Posts: 1,724
Default

Gotcha. I've never found an appreciable discrepancy between the two Dynon fuel quantity indications (float and calculated). I don't trust it completely, but I trust it more than I ever did the spam cans I used to fly. Those were good for a rough estimate only.

I don't miss the visual window at all. On my particular plane its only apparent function was to drip fuel into the carpet and under the baggage area floor. By the time I got it, the thing was mostly opaque and useless for seeing the fuel quantity. The Moeller gauge was a nice addition, allowing me to see the rough level while fueling.
__________________
Dale
Omaha, NE
RV-12 # 222 N980KM "Screamin' Canary" (bought flying)
Fisher Celebrity (under construction)
Previous RV-7 project (sold)
-=VAF=- 2017 dues paid
Reply With Quote
  #19  
Old 02-28-2017, 06:49 AM
f1rocket's Avatar
f1rocket f1rocket is offline
 
Join Date: Jan 2005
Location: Martinsville, IN
Posts: 2,260
Default

In looking at Jean-Pierre's original title to this thread, I think the best compliment to the Moeller gauge is a rope. That's so when you throw it overboard to use as an anchor, you can haul it back up!

Okay, just kidding, but I've never found this gauge to be of any use whatsoever. I know you sealed up your sight gauge openings, but I still think this is the best way to confirm fuel level.



I also found that if you carefully calibrate the fuel sender, shaking the airplane after each 2 gallons, and then installing the sender so that it handles the bottom part of the tank all the way down, this is pretty accurate. I've flown down to 2 gallons or less a couple of times.

I've adjusted the fuel flow calibration a bunch of times but I always reset it during flight multiple times to what the fuel sender says.

Just my $.02.
__________________
Randy Pflanzer
Martinsville, IN (II87)

www.pflanzer-aviation.com
Paid through 2043!
Lund fishing Boat, 2017, GONE FISHING
RV-12 - Completed 2014, Sold
427 Shelby Cobra - Completed 2012, Sold
F1 EVO - partially completed, Sold
F1 Rocket - Completed 2005, Sold
RV-7A - Partially completed, Sold
RV-6 - Completed 2000, Sold
Long-EZ - Completed 1987, Sold

Reply With Quote
  #20  
Old 02-28-2017, 07:26 AM
tomkk's Avatar
tomkk tomkk is offline
 
Join Date: Apr 2014
Location: Port Orange, Fl
Posts: 673
Default

Quote:
Originally Posted by f1rocket View Post
... I've adjusted the fuel flow calibration a bunch of times but I always reset it during flight multiple times to what the fuel sender says.
Pretty much the same with me. My measured fuel quantity is consistently amazingly accurate. I mean accurate to a couple of tenths of a gallon or so accurate.

I rarely look at my Moeller gauge. The computed fuel flow reading is interesting but I know what my burn rate is and don't really need the readout.
__________________
Tom
Port Orange, Fl
RV-12 N121TK ELSA #120845
First flight 06/10/2015
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 09:58 PM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.