Fuel Management

[txflyer]

I'm looking for different strokes from everyone from students to pro's how you manage your fuel on those long cross country's. Maybe we'll learn something.

I have extended tanks on the C-180, 81 gallons, 78 usable. When I'm flying long distance, I set my timer for every thirty minutes and switch left/right. I don't run both all the time X-country. If I'm alone, I start with the pilot side and try to burn balanced.

Naturally, I want to arrive with enough fuel for reserves, and not have to worry about the dreaded unporting issue in the pattern. School me.

 

[Jhernandez04]

84 gallons useable here.


I take off on the main left tank (25gal) then switch to left tip tank(17gal) after 1hr. Then switch to right tip after 30 minutes and land on right main tank.

 

[EdFred]

Left tip :15 usable
Left main: 28 usable
Right main: 28 usable
Right tip: 15 usable

Take off on both mains, switch to both tips when I get to cruise altitude. When the tips get down to 1/4 tank, I fly on one until it dry tanks. Then I dry tank the other tip. Then I burn off the left tank for an hour. By this time I have to pee, and I land; Still having 43 gallons or so remaining.

 

[Kelvin]

Do you actually change tanks in a Cessna? I do not recall ever touching the tank switch in my 172 or 182. Is the 180 any different? Do the tank extensions require a different procedure?

I fly a PA46...120 gallons..I switch tanks every 30 minutes...I have a 15 minute timer and a 30 minute timer that I keep running to keep my mnd in the fuel tank and fuel imbalance thought process...

 

[txflyer]

Do you actually change tanks in a Cessna? I do not recall ever touching the tank switch in my 172 or 182. Is the 180 any different? Do the tank extensions require a different procedure?

I fly a PA46...120 gallons..I switch tanks every 30 minutes...I have a 15 minute timer and a 30 minute timer that I keep running to keep my mnd in the fuel tank and fuel imbalance thought process...

I could run both all the time I suppose, because they are just larger bladders, 41 each side, but I guess I just like to stay busy and watch the needles for confirmation.

If you're slipping a little, (I don't have rudder trim) you could say one tank might feed less, but I haven't seen it happen for all practical purposes.

 

[N747JB]

I run the 182 on both almost all the time, the left side feeds faster than the right, but it's not a huge deal. I don't normally fly really long trips that stretch the fuel range or reserves.

 

[Henning]

I'm looking for different strokes from everyone from students to pro's how you manage your fuel on those long cross country's. Maybe we'll learn something.

I have extended tanks on the C-180, 81 gallons, 78 usable. When I'm flying long distance, I set my timer for every thirty minutes and switch left/right. I don't run both all the time X-country. If I'm alone, I start with the pilot side and try to burn balanced.

Naturally, I want to arrive with enough fuel for reserves, and not have to worry about the dreaded unporting issue in the pattern. School me.

I use a base time/fuel as a comparative reference and use the JPI fuel flow hooked to the 430w for fine management. I burn about an hour out of my mains, switch to my auxes, run them dry, then switch back to mains to finish the flight. Every now and then I look at the fuel gauges to see if they are in the ballpark in case I have a leak.

 

[Jhernandez04]

I use a base time/fuel as a comparative reference and use the JPI fuel flow hooked to the 430w for fine management. I burn about an hour out of my mains, switch to my auxes, run them dry, then switch back to mains to finish the flight. Every now and then I look at the fuel gauges to see if they are in the ballpark in case I have a leak.

So when you say run them dry do you mean that you actually completely drain the useable fuel to where the engine sputters or dies? Then you switch?

Sorry if that's a silly question.

 

[Jim Logajan]

In the C-152 I most commonly fly I like to set the fuel lever to "On" rather than "Off" and I hardly ever change it during flight.

Maybe we'll learn something.

Or not.

 

[Henning]

So when you say run them dry do you mean that you actually completely drain the useable fuel to where the engine sputters or dies? Then you switch?

Sorry if that's a silly question.

Not a silly question at all, yes, that's exactly what I do. Leaving a small amount in my aux tanks isn't wise because in the twin Cessna system all return fuel from the injection system (the system flows more fuel than it uses) returns to the mains at a rather unpredictable rate. If I don't run them dry, I have an unknown (at least accuracy unknown) quantity of fuel in my mains.

 

[Jhernandez04]

Not a silly question at all, yes, that's exactly what I do. Leaving a small amount in my aux tanks isn't wise because in the twin Cessna system all return fuel from the injection system (the system flows more fuel than it uses) returns to the mains at a rather unpredictable rate. If I don't run them dry, I have an unknown (at least accuracy unknown) quantity of fuel in my mains.

The reason I ask is during a xc I had miscalculated fuel consumption and ran out of fuel in on tank and the engine died, creating what I consider my first in flight emergency. The plane died and I quickly changed to my main tank and shortly after she fired right back up.

So that type of fuel management is common?

 

[Geico266]

60 gallons total, burn rate is 10.5 per hour running LOP. I start on the left tank then switch every hour until there is 3 gallon in one tank. That is about 5 hours. I need to pee after 4 hours. You do the math.

I watch the timer in the 496. I like the fact I don't have to start the timer. It starts when the plane starts moving faster.

I don't run the tanks dry. Just too much stress watching the fuel gages and hearing the big fan sputter. I've done it, I just don't like doing it.

 

[airguy]

I guess I just don't understand the widespread fear of running a tank dry - if you've got proper fuel filters in place to prevent sucking junk into the pump/carb/FI body, then all you've got is a vapor bubble that is displaced within a second or so of switching tanks and regaining fuel pressure. The engine stumbles just like it would if you had pulled the mixture, pulled the throttle, or pulled the mags - restore the offending missing item and continue on. The loss of power is not more than a few seconds. Unless you are flying passengers that are highly allergic to this type of momentary power loss I just don't see the issue. Do you not practice stalls for the same reason, that you might lose lift for a second or two? Do you not fly IFR in IMC, fearing that you might lose visibility?

If you don't know where the walls are, how will you know what to do when you reach them?

 

[Geico266]

I guess I just don't understand the widespread fear of running a tank dry - if you've got proper fuel filters in place to prevent sucking junk into the pump/carb/FI body, then all you've got is a vapor bubble that is displaced within a second or so of switching tanks and regaining fuel pressure. The engine stumbles just like it would if you had pulled the mixture, pulled the throttle, or pulled the mags - restore the offending missing item and continue on. The loss of power is not more than a few seconds. Unless you are flying passengers that are highly allergic to this type of momentary power loss I just don't see the issue. Do you not practice stalls for the same reason, that you might lose lift for a second or two? Do you not fly IFR in IMC, fearing that you might lose visibility?

If you don't know where the walls are, how will you know what to do when you reach them?

Good point. It is good practice. I've done it, I just don't like doing it.

 

[Henning]

The reason I ask is during a xc I had miscalculated fuel consumption and ran out of fuel in on tank and the engine died, creating what I consider my first in flight emergency. The plane died and I quickly changed to my main tank and shortly after she fired right back up.

So that type of fuel management is common?

Yep, no emergency at all, quite common for people who regularly use their planes for long range travel.

 

[Henning]

I guess I just don't understand the widespread fear of running a tank dry - if you've got proper fuel filters in place to prevent sucking junk into the pump/carb/FI body, then all you've got is a vapor bubble that is displaced within a second or so of switching tanks and regaining fuel pressure. The engine stumbles just like it would if you had pulled the mixture, pulled the throttle, or pulled the mags - restore the offending missing item and continue on. The loss of power is not more than a few seconds. Unless you are flying passengers that are highly allergic to this type of momentary power loss I just don't see the issue. Do you not practice stalls for the same reason, that you might lose lift for a second or two? Do you not fly IFR in IMC, fearing that you might lose visibility?

If you don't know where the walls are, how will you know what to do when you reach them?

Since fuel is sucked from the bottom of the tank, and all the 'junk' resides in the bottom of the tank, running the tanks dry doesn't really do anything to 'add junk' to the fuel stream.

 

[Geico266]

The reason I ask is during a xc I had miscalculated fuel consumption and ran out of fuel in on tank and the engine died, creating what I consider my first in flight emergency. The plane died and I quickly changed to my main tank and shortly after she fired right back up.

So that type of fuel management is common?

Gets your attention right away, doesn't it?

I was on a cc in s new to me RV- 9a. Ran one tank out. The gage still said 7 gallons left. Scared the crap out of me. The second tank said I had 7 ga!lons left also.





I landed at the next airport.

 

[kyleb]

Two tanks on the RV, 19 gallons a side. The fuel burn averages 8 GPH, but is more like 7 in cruise.

My fuel management is done by the watch on my arm, cross checked with the (so-far) accurate fuel gauges.

I run 30 minutes on the first tank, then an hour per tank for 3 hours after that. I'm never more than about 4 gallons out of trim that way.

After 3.5 hours, I have 7 gallons in one tank, 3+ in the other. If the mission requires, I'll run the 3 gallon tank dry and finish the flight on the full tank.

During the flight test period for my airplane, I tested running a tank dry several times. From the point the engine quits, it takes about 10 seconds to restore power. I have no qualms about running a tank dry.

 

[poadeleted20]

Your technique is pretty much what I use in single-engine aircraft with no BOTH position. However, I see no particular reason to leave the BOTH position in a light single in cruise unless I'm starting to get a significant imbalance, and will go back to BOTH once the imbalance is rectified.

 

[Geico266]

Since fuel is sucked from the bottom of the tank, and all the 'junk' resides in the bottom of the tank, running the tanks dry doesn't really do anything to 'add junk' to the fuel stream.

I've seen a little crud in the last few gallons. I have no idea where it comes from, but that is why I like to leave 3 gallons. Maybe just superstition on my part.

 

[airguy]

Since fuel is sucked from the bottom of the tank, and all the 'junk' resides in the bottom of the tank, running the tanks dry doesn't really do anything to 'add junk' to the fuel stream.

You make my point for me.

This is the primary argument I hear from people speaking against running a tank dry - that we will suck "junk" from the bottom few ounces of fuel into the pickups and thus into the pump/carb/FI, causing a long-lasting problem rather than a momentary hiccup - but if that was the case with the "junk" settling down in the lowest part of the tank, it would have long since been captured by the filter(s). That's why the filters are there. If you make the argument that the junk is lighter than the fuel and floats, and only gets caught during a dry-tank scenario, then I would still say that the fuel filters will catch it, and you should have seen the "floaties" in the top of the tank when you did a proper preflight, pulling the fuel tank caps and visually checking the fuel level. They weren't there, were they?

Your technique is pretty much what I use in single-engine aircraft with no BOTH position. However, I see no particular reason to leave the BOTH position in a light single in cruise unless I'm starting to get a significant imbalance, and will go back to BOTH once the imbalance is rectified.

The only time I've gone from BOTH to single tank-draw in a high wing single was to verify that there was not a problem feeding from either tank, and I most likely needed a bit of rudder trim to get a little closer to "coordinated" in cruise. On a 3-hour cruise leg (which I do a lot of) it's amazing how quickly a fuel imbalance can show up without appearing on the slip/skid ball.

 

[Geico266]

Two tanks on the RV, 19 gallons a side. The fuel burn averages 8 GPH, but is more like 7 in cruise.

My fuel management is done by the watch on my arm, cross checked with the (so-far) accurate fuel gauges.

I run 30 minutes on the first tank, then an hour per tank for 3 hours after that. I'm never more than about 4 gallons out of trim that way.

After 3.5 hours, I have 7 gallons in one tank, 3+ in the other. If the mission requires, I'll run the 3 gallon tank dry and finish the flight on the full tank.

During the flight test period for my airplane, I tested running a tank dry several times. From the point the engine quits, it takes about 10 seconds to restore power. I have no qualms about running a tank dry.

I would say 10 seconds is about right. Seemed like a week. Ask me know I know.

 

[Geico266]

I'm looking for different strokes from everyone from students to pro's how you manage your fuel on those long cross country's. Maybe we'll learn something.

I have extended tanks on the C-180, 81 gallons, 78 usable. When I'm flying long distance, I set my timer for every thirty minutes and switch left/right. I don't run both all the time X-country. If I'm alone, I start with the pilot side and try to burn balanced.

Naturally, I want to arrive with enough fuel for reserves, and not have to worry about the dreaded unporting issue in the pattern. School me.

Great topic Txflyer. Running out of fuel is the number one way pilots are forced into off field landings. Avoid running out of fuel and you put the odds a little more in your favor.

 

[airguy]

I would say 10 seconds is about right. Seemed like a week. Ask me know I know.

Go up to altitude and practice a real engine out. Pull the mixture, pull the nose up, stop the prop, glide down to deadstick landing.

Now do it three more times.

10 seconds seems trivial after that, and you'll be a little more prepared for true ugliness should it happen.

Yeah, I know - I've heard all the talking heads say that it's tempting fate and inviting problems - but it's the problems that I deal with on a regular basis, I know their smell, and those are not the ones I fear.

 

[txflyer]

I ****ed up one trip and hit a wicked head wind way the hell out in West Texas where fuel stops are far and few between.

Deviating into Plainview, making my way into the pattern, I banked, and you guessed it, she started bucking. When I rolled level, all was well. I got down o.k. and filled up.

Funny thing was, in my intense concentration on fuel, I never looked up or noticed a control tower until on downwind. Fort Worth flight following never handed me over, and I thought, oh brother, here we go. But no one ever said anything as I announced my intentions like a dumbass VFR at non-towered on unicom. I was relieved when the line boy said "oh, it's been closed for a while."

 

[Geico266]

Go up to altitude and practice a real engine out. Pull the mixture, pull the nose up, stop the prop, glide down to deadstick landing.

Now do it three more times.

10 seconds seems trivial after that, and you'll be a little more prepared for true ugliness should it happen.

Yeah, I know - I've heard all the talking heads say that it's tempting fate and inviting problems - but it's the problems that I deal with on a regular basis, I know their smell, and those are not the ones I fear.

Took about 8 mins from cutting the engine until I landed.

https://www.youtube.com/watch?v=_xZmsxEewik&feature=youtube_gdata_player

 

[airguy]

Nice.

[Yoda]

Preaching to the choir, am I...

[/Yoda]

 

[Jhernandez04]

I should practice a deadstick landing or two. But I'll wait till I'm a little more experienced

 

[Geico266]

Nice.

[Yoda]

Preaching to the choice, am I...

[/Yoda]

You are dead on, I just don't like it!

I don't like surprises. Every time I run a tank out I know it is going to stop the engine, but it still scares the crap out of me.

 

[kyleb]

Go up to altitude and practice a real engine out. Pull the mixture, pull the nose up, stop the prop, glide down to deadstick landing.

Now do it three more times.

10 seconds seems trivial after that, and you'll be a little more prepared for true ugliness should it happen.

Yeah, I know - I've heard all the talking heads say that it's tempting fate and inviting problems - but it's the problems that I deal with on a regular basis, I know their smell, and those are not the ones I fear.

I've done the whole Bob Hoover routine in the RV. Engine out with the prop windmilling to check the glide ratio. Fly slower to stop the prop, then back to best glide to check the prop stopped glide ratio. Followed by dead stick aerobatics (a few rolls, nothing in the vertical), then a dive to establish the speed needed to start the prop windmilling again (140 knots, FYI), then a windmilling restart. I've never had the willpower to go below about 3,000' AGL during this testing.

I have killed the engine on short final to get some idea of how the airplane would handle at the last phase of a forced landing.

As long as you do a decent job of planning your engine out trials, you're probably (big picture) improving your overall odds as PIC.

 

[airguy]

I've done the whole Bob Hoover routine in the RV. Engine out with the prop windmilling to check the glide ratio. Fly slower to stop the prop, then back to best glide to check the prop stopped glide ratio. Followed by dead stick aerobatics (a few rolls, nothing in the vertical), then a dive to establish the speed needed to start the prop windmilling again (140 knots, FYI), then a windmilling restart. I've never had the willpower to go below about 3,000' AGL during this testing.

I have killed the engine on short final to get some idea of how the airplane would handle at the last phase of a forced landing.

As long as you do a decent job of planning your engine out trials, you're probably (big picture) improving your overall odds as PIC.

Exactly correct. It's all about energy management. Just because you remove the energy-input side of the equation does not mean you die - it just means you have to manage what you have left. The airplane doesn't know it's not an airplane anymore, it still flies according to the same rules it followed since its first flight - you just have to acknowledge that this time gravity has the upper hand and will determine the final altitude at which the flight will terminate - but you still get to choose the final latitude and longitude, and the airspeed with which you will arrive there.

3 out of 4 ain't bad... as long as you don't panic and quit flying the damn airplane.

 

[geneseib]

I'm looking for different strokes from everyone from students to pro's how you manage your fuel on those long cross country's. Maybe we'll learn something.

Naturally, I want to arrive with enough fuel for reserves, and not have to worry about the dreaded unporting issue in the pattern. School me.

I make the first change after 30 minutes. Then after that I only have to change once every hour to keep the tanks within 30 minutes of each other.

 

[txflyer]

At the end of a X-country, sometimes I will go by the ETE on the 496. If it says 30 minutes ETE, and I've just switched, I'll run 15 on one side, and 15 on the other just for no reason at all really.

I like to think being somewhat balanced helps landing, but that's just me being too anal about it.

 

[Henning]

I should practice a deadstick landing or two. But I'll wait till I'm a little more experienced

It's like practicing bleeding lol. Just make sure you do it over the runway

 

[BillTIZ]

T-41B has two mains at 26gal each and a 17gal fuselage tank.
The fuselage tank only pumps up to the right main.
Takeoff on both, switch to right main for 1 hr, burns 10gph, switch to left, refil right from fuselage tank, about 15 min.
Turn off fuel pump from fuselage and switch back to right main.
1hr on right, back to left, pump fuselage tank into right tank to empty.

So now I'm down about 30 min in the left and the right is almost full.
Work it on both from there. Monitor for imbalance, the left tends to empty faster when on both. Rigging or tank vent is on left side. Switch to both for landing.

 

[txflyer]

Has anyone ever un-ported their fuel, and what was the aerodynamic's that did it?

 

[Henning]

Has anyone ever un-ported their fuel, and what was the aerodynamic's that did it?

http://www.pilotsofamerica.com/forum/showthread.php?t=64383

 

[EdFred]

I would say 10 seconds is about right. Seemed like a week. Ask me know I know.

10 seconds. I bet if you time it, it's more like three second. I've killed the engine a number of time through dry tanking, its never been close to 10 seconds. Maybe you want to check your fuel selector.

 

[Henning]

10 seconds. I bet if you time it, it's more like three second. I've killed the engine a number of time through dry tanking, its never been close to 10 seconds. Maybe you want to check your fuel selector.

Mine give enough advance notice in the stumble that they rarely actually die off altogether, and then it's on again within a second or two.

 

[kgruber]

In a Beaver you just watch the fuel pressure gauge. When it wiggles.......switch tanks. There isn't the slightest engine change.