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One empty gas tank????


procharger

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Rule of thumb: if you can see fuel so can your engine.

 

If one tank is dry you don't want to slosh remaining fuel outboard. If it is inboard and available to the engine you can see it.

 

The normal vector for fuel flow is down towards then engine. A second vector towards the trailing wingtip is added when in un-coordinated flight. If that happened it needs to be reversed towards the other wingtip in order to keep the remaining fuel available.

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Did you take your plane to an A&P and have them do a drain test on the tanks? I am told that if a tank winglet vent is clogged or the tube leading from tank to vent inside gets kinked or crusted you can get differing drain rates. If the vents are clogged, the repair is not easy though. they have to get inside the wing.

 

Both wings are supposed to drain into a common hose that leads to the header tank in my case and then via pump into the injection system. The older planes are similar, but use gravity I think from tank to carbs.

 

You can also get an abnormal drain if you are not coordinated. In fact, it was something discovered with a customer's plane a while ago, the avionics shop did some work and they moved the turn coordinator, and didn't balance it back out. It kept draining one tank first.

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Most CT's do drain one tank faster. There are several factors, both pilot and factory caused, but they should never be an issue if you have any knowledge about your plane at all. All of us have done just fine since 2004 and the only people that have crashed landed are the ones that take fuel in both wings down to a bare minimum.

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...the only people that have crashed landed are the ones that take fuel in both wings down to a bare minimum.

 

HUH?

 

Unless you have a restriction that will not permit 3gal/hr on one side this is all about motivation. The fuel is motivated by gravity or G forces to flow towards the engine if your nose is in the relative wind, if not the fuel is also motivated to flow towards the trailing wing tip. The trailing wing tip will be the low wing in strait flight.

 

If you can believe Yorktown that he had 3-4 gallons in one wing when he realized starvation then his slip had to be pronounced. It takes a bigger slip to slosh 4 gallons outboard than it does to slosh 2 gallons. Drain 1 wing and then in flight see how much of a slip it takes to make the fuel disappear from the sight tube. This amount of slip would be what you need to realize starvation. [use caution]

 

Yorktown is focused on a design flaw and fails to articulate what the flaw is beyond the ability to realize starvation with fuel in one wing. This is a design flaw common to all high wing fuel tanks, the sight tube is the salvation, if you can see fuel so can your engine.

 

Yorktown's suit is analogous to suing a 5gal fuel jug manufacturer because fuel will not flow out of his jug without tipping it 1st.

 

My CT will not deliver fuel while inverted so as the pilot I keep my plane upright most of the time. It will fly in a slip but only until it realizes starvation so as the pilot I stay coordinated when one tank is empty and the other is low.

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HUH?

 

Unless you have a restriction that will not permit 3gal/hr on one side this is all about motivation. The fuel is motivated by gravity or G forces to flow towards the engine if your nose is in the relative wind, if not the fuel is also motivated to flow towards the trailing wing tip. The trailing wing tip will be the low wing in strait flight.

 

If you can believe Yorktown that he had 3-4 gallons in one wing when he realized starvation then his slip had to be pronounced. It takes a bigger slip to slosh 4 gallons outboard than it does to slosh 2 gallons. Drain 1 wing and then in flight see how much of a slip it takes to make the fuel disappear from the sight tube. This amount of slip would be what you need to realize starvation. [use caution]

 

Yorktown is focused on a design flaw and fails to articulate what the flaw is beyond the ability to realize starvation with fuel in one wing. This is a design flaw common to all high wing fuel tanks, the sight tube is the salvation, if you can see fuel so can your engine.

 

Yorktown's suit is analogous to suing a 5gal fuel jug manufacturer because fuel will not flow out of his jug without tipping it 1st.

 

My CT will not deliver fuel while inverted so as the pilot I keep my plane upright most of the time. It will fly in a slip but only until it realizes starvation so as the pilot I stay coordinated when one tank is empty and the other is low.

 

From what I have read about that accident, I would be shocked if Barnath had 3-4 gallons at the time his engine failed. After all, no fuel was found in the airplane after the crash, because "it all sloshed out" (uh-huh). I bet he had 1-2 gallons when he took off.

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Andy,

 

Due to the angle on the face of the binnacle as well as the fact that it just sits there and can be moved the slip/skid ball is suspect.

 

I don't know if 1-2 or 3-4 is right but I do know that when fuel got critical, when fuel remained in one side only it wasn't monitored. All you have to do is look and keep remaining fuel visible at the wing root and you can use that remaining fuel.

 

You can and should check your slip/skid ball calibration by comparing against your sight tubes. One side at a time, you can find coordination by first using too much left rudder, then too much right rudder, then find the middle. Now do the other side and make a final determination where the middle is and compare that to your slip/skid ball. The sight tubes cannot lie but the ball can.

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The only time I ever got low enough for concern (nothing showing in the left tank) was coming back direct from NJ. 6.5 hours non stop..I was thankful for a straight in to 20 as I didn't want to make that right turn and unport the tank that had fuel....I checked how much was in the tank and it was 5.5 gal...During the next fill I also verified the lines on the sight tubes for accuracy, they were pretty damn close...As soon as I get a good feel for the best fuel flow/totalizers one will be installed..

The tubes are great during the day but they sure are a PITA at night....

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A right turn won't unport fuel any more than a left or even level flight. G-forces in a coordinated turn vector fuel towards the engine just like gravity in level flight. When turning with an empty tank reference the sight tube with fuel and keep fuel at the root.

 

A flow/totalizer can even lead to false security if the remaining fuel is all on one side and sloshed outboard.

 

Check your cabin light dimmer, my sight tubes are well lit and can be seen at night.

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A header tank, like on the CTLSi, would make unporting tanks a moot point.

 

Really?

 

You can still unport the wing tank with remaining fuel in a slip and if you hold that condition the header tank will starve with fuel outboard in 1 wing.

 

The point only become moot when the unporting is for a short period of time, like in a sloppy 90 degree turn.

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As per law suit, anyone run one wing dry, I believe I did when I first started flying ct, got back checked fuel, one side appeared to be dry other had about 5 gals plane ran fine, who else has done this and what were the results??

 

Yes, this has happened to me , and I found I had not locked the gas tank cap completely. That tab on top of the gas tank was up instead of down all the way. Hope this helps someone. If I take special care not to forget this , it does not happen. The locked tank drains faster.

 

Cheers

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A right turn won't unport fuel any more than a left or even level flight. G-forces in a coordinated turn vector fuel towards the engine just like gravity in level flight. When turning with an empty tank reference the sight tube with fuel and keep fuel at the root.

 

A flow/totalizer can even lead to false security if the remaining fuel is all on one side and sloshed outboard.

 

Check your cabin light dimmer, my sight tubes are well lit and can be seen at night.

 

CharlieTango,

Are you saying that with:

No fuel showing in the right tank(starboard) and no fuel showing in the left wing(port) and considering 2 right turns at 30deg....downwind to base and base to final. That the fuel will not get un ported?

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Really?

 

You can still unport the wing tank with remaining fuel in a slip and if you hold that condition the header tank will starve with fuel outboard in 1 wing.

 

The point only become moot when the unporting is for a short period of time, like in a sloppy 90 degree turn.

 

CT- I wasn't talking about someone flying along for a prolonged period of time with one dry tank and not being able to see anything in the sight gauge of the other tank. I should have been clear.

 

I was talking about the sloppy 90 degree turn or, perhaps, a long, slipping, final with the need to go around at the bottom.

 

The header tank has what, 1.3 gallons. That would be 15 - 20 minutes in cruise and a lot longer in the pattern. Anyone who would unport for that long is not paying attention, needs some training, or is brain dead and might want to consider another hobby.

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I don't know why any half-way intelligent pilot would ever run low on fuel unless he got caught above a cloud layer or some such problem as that. I would say ALWAYS fuel your plane to the maximum allowable weight before each flight. If your intended flight gets you anywhere close to being low on fuel, plan a fuel stop. Monitor your ground speed during flight and alter your plan if you are going to get low on fuel.

 

It can happen. Somewhere in this forum I posted about a low fuel experience I had in about 1975 or 76 in the Yukon. I was a lot younger, invincible, and less than half way intelligent on that day. Oh, did I mention stupid?

 

Seems most accidents are the result of a chain of events. You have to break the chain before its too late. But, when you paint yourself into a corner it can be too late.

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CharlieTango,

Are you saying that with:

No fuel showing in the right tank(starboard) and no fuel showing in the left wing(port) and considering 2 right turns at 30deg....downwind to base and base to final. That the fuel will not get un ported?

 

30deg or 45deg makes no difference, if you are coordinated the drain is just like level flight. Think about your head in a steep turn, it doesn't fall onto the door you are instead sucked strait down into your seat, the fuel is motivated in the same direction, for you its your butt into the seat, for the fuel its towards the engine as usual. I would use the steeper turn because it takes only a few seconds, if you draw out a turn and you unport there would be more time to use the fuel in the float bowl and fuel lines.

 

However if I had no visible fuel left or right I would either find some fuel or land and expect a dead stick landing. Before executing the emergency landing I would yaw left and right and if fuel appeared when doing so I would hold that position where I could see fuel at the root, as long as I can see it so can my engine. If you had 2 90deg turns to make you could/should make them in a slip that keeps the fuel visible.

 

Maybe your CT is different, when my tubes are dry my tanks are empty.

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Which is more stupid?

  • Running out of gas due to poor planning
  • Running out of gas due to failure to do a proper pre-flight inspection
  • Running out of gas due to failure to monitor ground speed
  • Running out of gas with gas onboard due to not understanding how to control the most basic of all fuel systems ( gravity fed, single, high wing, Off / On valve only, sight tubes )
  • Calling the most basic system a design flaw and suing FD

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I cut it pretty close coming back from Walnut Ridge, AK. This was when I thought the dipstick marks were more accurate than they really are (I now subtract 2 gal from what it says). Because of the bumps in the afternoon, it was hard to get a good reading once they got below the 5 gallon mark. I figured I had 3 in both sides when I was 40 miles out, but in what seemed like 10 minutes, the left tank didn't show any fuel at all. I trimmed to keep the right wing up and cut back on the speed (I had already cut 5 kt off my cruise), but because I was about 10 miles from both home and KTKI, I decided to proceed.

 

I got on the ground OK, and the first thing I did after shutdown was get out the dipstick. 2.5 gallons on the right wing, nothing on the left. Still 30 minutes worth.

 

On the bumpy approach there were a couple of moments when even the right side read zero, but then it would read 4-5 gal as fuel sloshed around.

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Pilots, myself included, have a tendency to react to other pilots mistakes by saying "how could anyone be that dumb, I would never do that".

 

Any of us who have been flying for awhile probably have stories to tell, or maybe we don't want to tell. The trick is to survive these moments, hopefully without bending metal, and learn from them.

 

And remember, "There, but for the grace of God, ...........

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I'm not willing to say I will never screw the pooch on fuel, I can only say I'm pretty paranoid about it. My big fear is that once I get to doing some really long flights in the CT I will misjudge fuel burn, ground speed, or winds and get in a low fuel state. That said, as I mentioned I am paranoid about fuel, and can't really see myself not checking the sight tubes for a period long enough to get to a critical fuel state with no available airports.

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Some planes might be more prone to uneven draining than others. Mine seems to drain pretty evenly, and it's not because I'm a master of perfectly coordinated flight, I can assure you.

 

It can be a factor of airflow too. If one tank is getting more air-vent pressure than the other, it will drain faster.

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