1st XC in the Cirrus. Learning to trust computers.

SixPapaCharlie

SixPapaCharlie

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I wanted Pizza last night but none of that Texas crap. I wanted the good pizza. You know, the kind they make in Tulsa. MMMMMMM Nobody thinks of Tulsa w/o thinking about pizza amirite?

I called my dad and said "You want to grab a pizza somewhere?" Of course his first words were "Only if it is from Tulsa"

Anyway.

We agreed after getting signed off, our first few flights would be with both of us in the plane together so both wives get a payout when we crash together. Also gives us the chance to assist on things we might miss.

The flight out was fine. Right at an hour to get there which was pretty nice. Flight back was nice, night time, very quiet. It really is a fantastic plane but there are learning curves and things I have to get used to.

One major adjustment is the computer helping to "manage" my fuel. CISP keeps telling me not to look at the fuel gauges and they are in an odd spot anyway. So we rely on math and the electronics. The Garmin tells me to switch tanks but has NO idea how much fuel I have used. It just does it every 30 min. So the first time it told me to switch, I had burned according to the Avidyne 4.2 gallons. So I now know the Garmin will be off for the remainder of the flight.

My personal rule is anytime the fuel burned equals 9 X an odd number, switch so, 9, 27, 45. that way we never exceed the 10 gal max imbalance specified in the POH.

Fuel Information
Begin @ tabs. So 46 Gal (Tail wind)
Burning 11.8-12.4 GPH
Land having burned 13 so 33 remaining.

Launch to head home. (headwind)
3/4 home and Avidyne shows:
Burning 13GPH, 16G Remaining, 20 min to go.

That tells me I am going to burn 4 gal and change and land w/ 12 in the tanks

At this point the FUEL light comes on on the panel. Then the Avidyne gives me a yellow indicator telling me I have < 16G on board.

So suddenly I am getting this information and starting to question if I should be doing something. Am I doing math right? Its night. I am suddenly not comfortable. One actual fuel gauge is near 5 and the other shows 10 but I am seeing fuel lights and notices about fuel and feel like the plane is telling me I should do something or I am going to have a fuel problem. I just tell my dad I am doing the math and it seems like we can make this w/ the legal requirement to spare but I know this avidyne doesn't know what is in the tanks and I am getting worked up in my head so Screw it, I landed at the closest field to get fuel.

Open the caps and both tanks appear empty. I am sure due to dihederal, there is fuel further down but with my little cigarette lighter, I couldn't see very far inside the tank toward the wing.

I filled it up to 86 Gallons for the 20 minute flight home and of course it only took 71 gallons to fill so the computer was dead accurate but it is going to take some getting used to. I don't like that it doesn't know which tank I am on so it doesn't know what is in which tank and it starts telling me about my fuel in multiple places.

Never was in any danger of having a fuel problem, but new plane at night w/ different systems and got myself spooked. The old plane had 2 gauges up front and when they were both at 1/4 we landed. Now there is a fuel light, and a notification that comes on at specific thresholds and the Garmin telling me to switch tanks. For being an IT guy, I don't have a ton of faith in computers.

Really a non-event but an example of how your mind can play tricks on you and get you concerned and provide a bit of self doubt when flying in a new situation.

Look forward to my next post about wondering if I did the W&B correctly taking off w/ 82 gallons of fuel but feeling like I might have miscalculated since the plane felt funny or something ;)

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Isn't looking in a cirrus wing scary when you have less than a half tank. I was shocked the first time I looked and saw no fuel at all.

The fuel totalizer on that big screen will likely be right on and very trustworthy. Atleast in the G1000 versions, they are more accurate than the fuel gauges in my experience.

That being said, you guys may want to look into the new fuel guages: https://www.ciescorp.net/
 
JasonM said:
Isn't looking in a cirrus wing scary when you have less than a half tank. I was shocked the first time I looked and saw no fuel at all.

The fuel totalizer on that big screen will likely be right on and very trustworthy. Atleast in the G1000 versions, they are more accurate than the fuel gauges in my experience.

That being said, you guys may want to look into the new fuel guages: https://www.ciescorp.net/
Click to expand...

Yeah, it was my first flight any distance and I have never seen a fuel light before. On my car when the fuel light comes on, it generally means I need fuel now.

Edit: also first time seeing "empty" tanks.
When I saw that, I thought the avidyne was miscalculating.
 
SixPapaCharlie said:
Open the caps and both tanks appear empty. I am sure due to dihederal, there is fuel further down but with my little cigarette lighter, I couldn't see very far inside the tank toward the wing.
Click to expand...

I keep a box of road flares around for such occasions when the fuel is hard to see inside the tank. They are hard to fish out afterwards though, so buy the short ones, or tie a string to it.
I, too, am getting used to the totalizer, I just wished my plane had a fuel pressure readout on the G1000. The totalizer has given me no reason to doubt it, except for the fact that I am surrounded by millivolt electronics that have failed at work. I'm going to keep a hand written fuel log.
 
Subsea said:
I keep a box of road flares around for such occasions when the fuel is hard to see inside the tank. They are hard to fish out afterwards though, so buy the short ones, or tie a string to it.
Click to expand...

A handheld propane torch works nice too and is reusable. ;)
 
SixPapaCharlie said:
. On my car when the fuel light comes on, it generally means I need fuel now.
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Ectually, not on cars built after 2004. The fuel light will come on with approx 2.5 gallons left in the tank. At ~30MPG you have roughly 75 miles, or more than an hour at fwy speeds to get gas. On a Prius, which I presume is your DD;) , you have ~120 miles before stoppage. Thank DOT if you like.

<edited to correct year of mandate. Oops >
 
SixPapaCharlie said:
I wanted Pizza last night but none of that Texas crap. I wanted the good pizza. You know, the kind they make in Tulsa. MMMMMMM Nobody thinks of Tulsa w/o thinking about pizza amirite?
Click to expand...

I can quite honestly say that I've never had pizza in Tulsa.
 
Clark1961 said:
I can quite honestly say that I've never had pizza in Tulsa.
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HA. I am not sure why but we gravitate to this joing called Hideaway.
It is more nostalgic than anything. We used to live in Tulsa ans frequented it.

It is nothing to write home about but good nonetheless.
And food is always better when you flew to get it.
 
docmirror said:
Ectually, not on cars built after 2004. The fuel light will come on with approx 2.5 gallons left in the tank. At ~30MPG you have roughly 75 miles, or more than an hour at fwy speeds to get gas. On a Prius, which I presume is your DD;) , you have ~120 miles before stoppage. Thank DOT if you like.

<edited to correct year of mandate. Oops >
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Never knew that. I figured there was some wiggle room but not that much.
 
Bryan, I believe you are in Dallas as well. Congrats on the new plane. I saw your original post when you got it but didn't get a chance to congratulate you.

I have an SR22 based at TKI. Actually just flew it back from an avionics upgrade in Boston this weekend.

I am not sure if you know or not but those fuel gauges are absolutely useless.. I don't know anyone with a Cirrus that uses them. In my opinion they are dangerous. You can have a tank that is significantly less full than the other and the gauges will indicate the opposite. CiES has digital gauges that can be installed that are supposed to be accurate.

I just trust the totalizer to backup my flight planning on the ground. Also, I have a message scheduled on the GTN650's to remind me to switch tanks every 30 minutes. The 430's will do this too.

I wish the FUEL light would indicate which tank is below the limit. That light comes on when either tank hits < 10 gallons.. So at 13.5 gph you could still have close to 1.5 hours left and the light be on.
 
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ipengineer said:
Bryan, I believe you are in Dallas as well. I have an SR22 based at TKI. Actually just flew it back from an avionics upgrade in Boston this weekend.

I am not sure if you know or not but those fuel gauges are absolutely useless.. I don't know anyone with a Cirrus that uses them. In my opinion they are dangerous. You can have a tank that is significantly less full than the other and the gauges will indicate the opposite.

I just trust the totalizer to backup my flight planning on the ground. Also, I have a message scheduled on the GTN650's to remind me to switch tanks every 30 minutes. The 430's will do this too.
Click to expand...

I don't like the 430 reminders because they don't account for the volume of fuel used, just time, so they include taxi, runup, and waiting where very little fuel is being consumed. The fuel guages down by the boost switch are what the cisp told me to ignore. I may start keeping a fuel log just to back up the avidyne also so I can confirm what is in each tank.
 
ipengineer said:
I wish the FUEL light would indicate which tank is below the limit. That light comes on when either tank hits < 10 gallons.. So at 13.5 gph you could still have close to 1.5 hours left and the light be on.
Click to expand...

That makes sense. So that light will be on if i have 9G in one tank and 20 in the other then.

I thought I had read or heard where that light came on when there was less than 12G total on board.

yeah, it would be nice if it indicated which tank.
 
SixPapaCharlie said:
[snip]
For being an IT guy, I don't have a ton of faith in computers.
[snip]
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It's BECAUSE you're an IT guy. (Me too!)

You'd never eat in a restaurant you'd been in the kitchen of either. :wink2:

John
 
SixPapaCharlie said:
I don't like the 430 reminders because they don't account for the volume of fuel used, just time, so they include taxi, runup, and waiting where very little fuel is being consumed. The fuel guages down by the boost switch are what the cisp told me to ignore. I may start keeping a fuel log just to back up the avidyne also so I can confirm what is in each tank.
Click to expand...

Valid point.. If I get in, start up after a refuel and within a few minutes the message goes off, I wont switch. I figure fuel burn is marginal on the ground. On COPA I noticed some people have the timer set to 20 minutes. The idea is more frequent switching is better.

If you aren't on COPA you should be; it is the best money I have spent trying to learn the nuances of the plane.
 
The Cirrus is quiet? Or the radio was quiet?

A Cirrus is the LOUDEST cabin I've ever heard when the engine is running. It must be why they come standard with Bose headsets.

Also:
Left side of the clock, left tank.
Right side of the clock, right tank.
 
Cpt_Kirk said:
The Cirrus is quiet? Or the radio was quiet?

A Cirrus is the LOUDEST cabin I've ever heard when the engine is running. It must be why they come standard with Bose headsets.

Also:
Left side of the clock, left tank.
Right side of the clock, right tank.
Click to expand...

They're always quieter at night. :)

I like the clock idea. That's pretty smart thinking.
 
Good call on the fuel stop - better to learn on the ground than on the air.

I'll have to keep Tulsa in mind for pizza. I've been to lots of places - Malnati's, Giordano's and Gino's in Chicago, Tony's in San Fran, Lola's in Minneapolis, Delancy in DC, Grimaldi's in Dallas and probably a dozen others that I've missed. So far in my travels the best pizza I've found has been Antico's in Atlanta.
 
Grimaldi's is really good but they can't keep up with the demand.
Meaning it is like they have 1 oven but the place is packed. If you order 2 pizzas, they will come out 30 min apart. I can't go there anymore w/ my kids because twice we have gone at a normal dinner hour and gotten out so late we blew by the evening routine.

I went once w/ my parents and it was the same deal.
I like the pizza though.

One of these days I am going to fly the plane to Chicago. There is a place (mi pi) up there that is on my list but the local one closed and the only one left is up there.
 
SixPapaCharlie said:
That makes sense. So that light will be on if i have 9G in one tank and 20 in the other then.

I thought I had read or heard where that light came on when there was less than 12G total on board.
Click to expand...

1) What does the POH say about what the light means?

2) That hypothetical fuel imbalance violates a limitation. Right?
 
SixPapaCharlie said:
That makes sense. So that light will be on if i have 9G in one tank and 20 in the other then.

I thought I had read or heard where that light came on when there was less than 12G total on board.

yeah, it would be nice if it indicated which tank.
Click to expand...

Check the POH page 7-60. You likely had far more fuel than you thought when the light came on.
 
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docmirror said:
Ectually, not on cars built after 2004. The fuel light will come on with approx 2.5 gallons left in the tank. At ~30MPG you have roughly 75 miles, or more than an hour at fwy speeds to get gas. On a Prius, which I presume is your DD;) , you have ~120 miles before stoppage. Thank DOT if you like.

<edited to correct year of mandate. Oops >
Click to expand...

Pro-tip: do not actually do this in a Prius.
 
ajyeary said:
Pro-tip: do not actually do this in a Prius.
Click to expand...

Pro-tip.

1) It's an estimate.

2) I had a 07 Prius and did 77 miles after the light came on no prob. Would it make 120? Don't know, but running out of gas in any car is a bad plan.
 
docmirror said:
Pro-tip.

1) It's an estimate.

2) I had a 07 Prius and did 77 miles after the light came on no prob. Would it make 120? Don't know, but running out of gas in any car is a bad plan.
Click to expand...

I've also got an 07, had the "Add fuel" message come up and couldn't even make the next exit before the car decided it was out of gas. Was only slightly embarrassing! :redface:

Edited to add/clarify: rural Ohio, "next exit" should read "next exit with known/listed fuel".
 
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I can't afford a prius. I am squeezing every last mile out of the 2 cars I have now.
both are at 120k and if I can get them to 200, that would be outstanding. If I can get to 150 I will take that
 
ajyeary said:
I've also got an 07, had the "Add fuel" message come up and couldn't even make the next exit before the car decided it was out of gas. Was only slightly embarrassing! :redface:

Edited to add/clarify: rural Ohio, "next exit" should read "next exit with known/listed fuel".
Click to expand...

Something is broke in there.

<edit; I believe the Prius has a bladder in the tank. I think your's is having trouble. Investigate why the bladder is not operating right, and you're running out so soon after the light comes on.>

<edit the edit: and here ya go: http://articles.sun-sentinel.com/2009-07-05/business/0907020366_1_fuel-tank-prius-gas-tank-bladder >
 
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In the Comanche, we have 4 tanks, so fuel management gets even more complicated.

What I do for a long range flight with tanks full is startup and get to cruise altitude, then take note of my total fuel burn and consumption rate, calculate when I will hit 14 gal burned, and set a countdown timer for that amount of time (or just watch for 14 gal on the totalizer).

When it hits 14 gal, I switch to the opposite aux tank, noting the value displayed on the fuel totalizer and calculate how much time I will spend on that tank to burn 14.5 gal at present burn rate (aux tanks are 15 gal capacity). Set countdown timer, and calculate "target" value on the totalizer for next tank switch.

Sometimes I like to do really long-range flights, so I installed the MS Excel app on my iPad and made a spreadsheet telling me exactly how much fuel is left in all 4 tanks at any time.

Ok, maybe this is overthinking it, but I like knowing _exactly_ what's in my tanks and it's something to do in cruise. Since burn rates can vary based on altitude or mixture setting, calculating how much time you'll need to spend on a tank and setting a countdown timer gives you a more accurate picture of what's in the tank.
 
docmirror said:
Something is broke in there.

<edit; I believe the Prius has a bladder in the tank. I think your's is having trouble. Investigate why the bladder is not operating right, and you're running out so soon after the light comes on.>

<edit the edit: and here ya go: http://articles.sun-sentinel.com/2009-07-05/business/0907020366_1_fuel-tank-prius-gas-tank-bladder >
Click to expand...

Was just about to type a response saying as much and that it's a known issue (at least on PriusChat). Glad I hit refresh first before we started having completely schizophrenic edit-based conversation :rofl:

Didn't mean to hijack the thread, just wanted to share my adventure/experience with the Prius re: the minimum fuel notice.
 
ajyeary said:
Was just about to type a response saying as much and that it's a known issue (at least on PriusChat). Glad I hit refresh first before we started having completely schizophrenic edit-based conversation :rofl:

Didn't mean to hijack the thread, just wanted to share my adventure/experience with the Prius re: the minimum fuel notice.
Click to expand...

Hey, no prob. The fuel rules were changed way back, but Prius is 'special' lol, cause it has the bladder for emissions.
 
Good decision to stop if you even START to worry about fuel. Getting fuel is no big deal.
 
SixPapaCharlie said:
I can't afford a prius. I am squeezing every last mile out of the 2 cars I have now.
both are at 120k and if I can get them to 200, that would be outstanding. If I can get to 150 I will take that
Click to expand...

Shouldn't be a problem with most any car.

My 1998 Honda Accord is at 250k on the original motor and transmission. Absolutely no problems with either.

Assuming the timing belt doesn't break before I replace it next month I expect no major issues going to 300k.
 
SixPapaCharlie said:
I wanted Pizza last night but none of that Texas crap. I wanted the good pizza. You know, the kind they make in Tulsa. MMMMMMM Nobody thinks of Tulsa w/o thinking about pizza amirite?

I called my dad and said "You want to grab a pizza somewhere?" Of course his first words were "Only if it is from Tulsa"

Anyway.

We agreed after getting signed off, our first few flights would be with both of us in the plane together so both wives get a payout when we crash together. Also gives us the chance to assist on things we might miss.

The flight out was fine. Right at an hour to get there which was pretty nice. Flight back was nice, night time, very quiet. It really is a fantastic plane but there are learning curves and things I have to get used to.

One major adjustment is the computer helping to "manage" my fuel. CISP keeps telling me not to look at the fuel gauges and they are in an odd spot anyway. So we rely on math and the electronics. The Garmin tells me to switch tanks but has NO idea how much fuel I have used. It just does it every 30 min. So the first time it told me to switch, I had burned according to the Avidyne 4.2 gallons. So I now know the Garmin will be off for the remainder of the flight.

My personal rule is anytime the fuel burned equals 9 X an odd number, switch so, 9, 27, 45. that way we never exceed the 10 gal max imbalance specified in the POH.

Fuel Information
Begin @ tabs. So 46 Gal (Tail wind)
Burning 11.8-12.4 GPH
Land having burned 13 so 33 remaining.

Launch to head home. (headwind)
3/4 home and Avidyne shows:
Burning 13GPH, 16G Remaining, 20 min to go.

That tells me I am going to burn 4 gal and change and land w/ 12 in the tanks

At this point the FUEL light comes on on the panel. Then the Avidyne gives me a yellow indicator telling me I have < 16G on board.

So suddenly I am getting this information and starting to question if I should be doing something. Am I doing math right? Its night. I am suddenly not comfortable. One actual fuel gauge is near 5 and the other shows 10 but I am seeing fuel lights and notices about fuel and feel like the plane is telling me I should do something or I am going to have a fuel problem. I just tell my dad I am doing the math and it seems like we can make this w/ the legal requirement to spare but I know this avidyne doesn't know what is in the tanks and I am getting worked up in my head so Screw it, I landed at the closest field to get fuel.

Open the caps and both tanks appear empty. I am sure due to dihederal, there is fuel further down but with my little cigarette lighter, I couldn't see very far inside the tank toward the wing.

I filled it up to 86 Gallons for the 20 minute flight home and of course it only took 71 gallons to fill so the computer was dead accurate but it is going to take some getting used to. I don't like that it doesn't know which tank I am on so it doesn't know what is in which tank and it starts telling me about my fuel in multiple places.

Never was in any danger of having a fuel problem, but new plane at night w/ different systems and got myself spooked. The old plane had 2 gauges up front and when they were both at 1/4 we landed. Now there is a fuel light, and a notification that comes on at specific thresholds and the Garmin telling me to switch tanks. For being an IT guy, I don't have a ton of faith in computers.

Really a non-event but an example of how your mind can play tricks on you and get you concerned and provide a bit of self doubt when flying in a new situation.

Look forward to my next post about wondering if I did the W&B correctly taking off w/ 82 gallons of fuel but feeling like I might have miscalculated since the plane felt funny or something ;)

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Wait, the new Cirrus doesn't have a fuel totalizer? The 430w takes input from the ones I know about, mine did with a JPI-760, and it would tell me when it would calculate I would cut into my reserves at ETA. That's a really nice feature on longer flights where you are traveling through various wind zones, and especially when the headwinds start picking up, you can immediately see how your range is affected,nand you have more advanced notice to make an earlier diversion towards cheaper fuel rather than figuring it out at the last minute and get stuck paying $7.50 a gallon. The best part though is when you get an unexpected tail wind and you see that you get to skip your intermediary stop.
 
jesse said:
Shouldn't be a problem with most any car.



My 1998 Honda Accord is at 250k on the original motor and transmission. Absolutely no problems with either.



Assuming the timing belt doesn't break before I replace it next month I expect no major issues going to 300k.
Click to expand...


I agree - 240k on my 2003 Protege5 and going strong, still on the original clutch even. 150k is barely middle aged for a modern car.

I did buy a new 2011 in Dec 2010 for road trips and such but the 03 is still my work commuter.


Sent from my iPhone using Tapatalk and 100% recycled electrons - because I care.
 
I was actually going to ask if you went to Hidaway. Good stuff. You do know that there are a few Hidaways in the city now, right?
 
OkieFlyer said:
I was actually going to ask if you went to Hidaway. Good stuff. You do know that there are a few Hidaways in the city now, right?
Click to expand...

PilotTangoCharlie flew me and Mrs. 6PC to one in Edmond once.
I used to live in OK, and never cared for Hideaway but it has grown on me.
I love it now. We need one in Texas.
 
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