Buckaroo Posted August 28, 2017 Author Report Share Posted August 28, 2017 One other thought I had! In my opinion the airplane must be fuel quantity inspected while compleley level! The tanks are long and as such with level plane and sticking straight down in the filler will only then give an accurate reading!? Example: Right now my right wing is 4 inches high. The stick shows 3 gallons. The tube shows 10.5 gallons. What if the only fuel is in the tube itself?? Link to comment Share on other sites More sharing options...
Tom Baker Posted August 28, 2017 Report Share Posted August 28, 2017 The fuel can not be just in the tubes, otherwise it would be always full or empty. While the airplane is sitting in the hangar if you could sit a construction laser level where it shines on the sight tube and the leading edge of the wing. Then put the line where it shines on the level of the fuel in the tube, and the level of the fuel in the tank will be marked by the line on the leading edge of the wing. Maybe this will help you visualize why the tube shows 10.5 gallons and the dip stick only measures 3. Link to comment Share on other sites More sharing options...
Buckaroo Posted August 28, 2017 Author Report Share Posted August 28, 2017 Tom yes I can picture because of the wing to high that the fuel bunches up in the wing root area and only shows 3 gallons at the stick area. This afternoon leveled the plane in great detail. With approximately 19 gallons on board in a settled state the right tank sticks 6 gallons and the left sticks 13. I waited an hour for drainage with no change. Tomorrow I will re-examine any further flow a see what happens. I ordered the pinch tool you suggested and when received will conduct a drain test. Question: Can I pinch the fuel line off with the fire sleeve on? Sort of wondering with the large sleeve will I know if it is indeed pinched totally off! Otherwise I have a band clamp to deal with and I don't want to deal with that. I now realize that erroneous fuel readings can come from a uneven and in level wing! Link to comment Share on other sites More sharing options...
Tom Baker Posted August 28, 2017 Report Share Posted August 28, 2017 Yes you can pinch through the fire sleeve. It will take a while for the fuel to level out. If it doesn't level out on its own I would investigate further. Link to comment Share on other sites More sharing options...
Buckaroo Posted August 28, 2017 Author Report Share Posted August 28, 2017 Tom, can you explain "level out"? What I planned to do is block each side for a given amount of time and drain the other and measure volume drained per time from each side. Link to comment Share on other sites More sharing options...
Buckaroo Posted August 29, 2017 Author Report Share Posted August 29, 2017 9 hours ago, FlyingMonkey said: Do you have fuel streaks from your filler caps to the backs of the wings? You could have some fuel leaking from the epoxy seals which has broken down over time. You should definitely do a drain test. Level the wings using boards to shim under the right wheel or a ladder under the right wing with towels padding against the wing to get the correct height. Fill both tanks up with about five gallons, enough that they fill about half the sight tubes. If on filling the tubes don't look roughly even, investigate why. If they look even, drain fuel from the gascolator into a container, while watching the sight tubes (don't get in the airplane to do this, it might "unlevel" it). If one empties completely, and there is still significant gas in the other tube, you have some kind of fuel flow problem on the still full side. Also, you can check the ball once the airplane is leveled this way to see if it's way out. You can do a quick eyeball coordination check in flight...in calm winds, when your ball shows centered, look at your wingtips. If they are each the same distance from the horizon, your instrument is close to correct. BTW, it's all too easy to fly these airplanes with one wing down, I end up doing it all the time and have to correct myself when I catch it. But with three axis trim you should be able to get it flying pretty straight in calm winds. Great advice and thanks for the time taken to help! I'm in the process of setting this baby up for a battery of tests! I need to sort this out as a top priority! It's either my stupidity or problems within this aircrafts system! I can handle both solutions with a goal of confidentiality flying this wonderful aircraft! I love my CTSW and really need to get things sorted. There's no other SLSA out there that matches all the wonderful positives of the CT line!?? Link to comment Share on other sites More sharing options...
Buckaroo Posted August 29, 2017 Author Report Share Posted August 29, 2017 Oh yes no streaks!? Link to comment Share on other sites More sharing options...
Runtoeat Posted August 29, 2017 Report Share Posted August 29, 2017 Buckaroo, now you're understanding this. I'm not sure you read the following post that was done when you first posted your situation? (Note the BOLDED sections): Posted Sunday 8:05am Listen to Corey. Get your plane level however you can do this in the hangar by measuring at the end wing tips to ground and placing blocks of wood under the wheel on the low side. Once you are level with the wings, adjust your ball to show level. Understand though, that the mushroom is not rigidly held to the firewall and will move around if you lean or push on it. This is typical with our CTSW's (and probably CTLS's too). This causes your ball callibration to change if you lean or pull on the mushroom after callibration. Once calibrated, find out if you do have a restricted fuel flow. While you still have your CT level, drain both tanks. Fill first one tank with a couple of gallons of fuel. Time how long it takes to drain this tank thru your gascolator. Fill the other tank. Time the drain of this one. Are they both equal? Does the time to drain meet Fight Design's spec? This then leads to following the advice of others here, which is, don't panic if you see one side low while flying. If you get in a situation where you see fuel only on one side and not the other, you still are providing fuel for the engine from the side with fuel. Just make sure you keep the CT in an attitude where you always see fuel on at least one side. I would keep the wood block you use to level your CT and make a ramp which allows you to push your CT onto this when parking in the hangar. This keeps the fuel in both tanks level and allows you to accurately dip the tanks before flying. Link to comment Share on other sites More sharing options...
Mike Koerner Posted August 29, 2017 Report Share Posted August 29, 2017 Buckaroo, As others have pointed out, fuel transfer from tank to tank is slow. It probably takes close to 5 minutes to transfer a one gallon with the slip and skid ball half a ball off centered. This is true whether you're parked on uneven ground or in flying straight with one wing low. You said that after landing the left tank, which had been showing virtually empty, was almost full again. Unless you were on unlevel ground, or you waited a long time after landing to take a look at the fuel tubes, that fuel was in that wing while you were flying. Apparently, though you thought you had "cleaned up" the bank angle after the fuel transfer, the left wing was still low. So the problem seems to be that when you think you're flying coordinated, in fact you are not. This could be an issue with the mounting of the slip indicator (as others have said) or parallax in your viewing of it (if it's not right in from of you) along with the sight picture in the airplane not being as you expect (I thought this was more of an issue with the round top instrument panels on the CT2k than the square ones on a CTSW). Andy's suggestion that you look out at the wing tips while flying straight is good over flat terrain, but your area of Montana that isn't going to work really well. Maybe you can project where the horizon would be absent the mountains. You might also try strapping a carpenter's level to the drag spar (the tube that runs across the top of the cockpit just in front of the main spar carry-through. I haven't tried this so I'm not sure it will work but it ought to (unless the bubble bounces around too much in flight to get a reading). I would not go hog-wild trying to speed up the fuel transfer by moving the ball further out. Remember that the tanks are vented and the vents are near the outboard end of the tanks. If you are too far off coordinated you'll dump fuel out the low wing's vent. I would go with 1/2 ball as Roger says, or 1 ball at the most. You're lucky to have a wife that flies with you. I recommend making the same trip once more to get this worked out, before taking her up again. Mike Koerner Link to comment Share on other sites More sharing options...
Tom Baker Posted August 29, 2017 Report Share Posted August 29, 2017 Remember that 5 GPH of the fuel you are trying to transfer is going to the engine instead of the other wing. Also when leveling use a level across the top of the cabin above the spar. Hangar floors can be uneven. Link to comment Share on other sites More sharing options...
FredG Posted August 29, 2017 Report Share Posted August 29, 2017 It's hard to know the rate that fuel transfers given some deviation of the ball from center. I suspect that it is very slow with a slip that deviates by a half-ball. By "very slow" I would think a couple of gallons per hour. But, that is just a guess. Remember, the smaller the difference in the height of the fuel tanks, the slower the transfer rate. Regarding procedures for leveling the wings in the hangar, there are a few methods and they have been discussed before. I place a 4 foot beam (a bubble level, but I don't use the level feature, it's just a straight rigid object) on the middle of the wing (span wise) and then put a digital protractor (digital level) on the beam and get the angle of the wing. I do this for both wings. Then I shim the wheel on the side of the low wing until the angle of the two wings is equal. Then I check the ball. The first time I did this the ball was not centered. So, I then moved the panel in order to center the ball. I consider this an essential aspect of rigging the airplane. I get that the panel is not as rigidly mounted as I would like. The advantage of leveling the wings (as opposed to the spar pass-through box of the fuselage) is that if the fuselage isn't perfectly symmetrical with respect to the wings, I still know the wings are level. That is what I want. If you want to be really, really sure that the fuel is equal in both tanks when the ball is level, then you could use fuel level in the wings as the means of leveling the plane. Fill the tanks partially, wait a day. Check fuel level. If one wing has more fuel than the other, then shim under the wheels (raise the wheel on the side with the fuller tank). Wait a day. Continue until the fuel is equal in both tanks. Then adjust instrument panel until the ball is centered. Now you know that when the ball is centered, fuel will not transfer from one wing to another. The problem is that you don't know if the wings are level physically, you only know that the fuel tanks are level when the ball is centered. Also, this method is at the mercy of any inaccuracy in sticking the wings for fuel level. I didn't do this, I found that when I leveled the wings using a digital level, the fuel in the tanks remained equal during coordinated flight. My airplane is experimental and I have inspection authority. Your situation may be different. My procedures are not offered as maintenance recommendations for you or your airplane, only as an example of one owner's approach to his own airplane. Link to comment Share on other sites More sharing options...
FredG Posted August 29, 2017 Report Share Posted August 29, 2017 Tom, in a slip, fuel will transfer. The engine will still draw from both tanks. Link to comment Share on other sites More sharing options...
Buckaroo Posted August 29, 2017 Author Report Share Posted August 29, 2017 All recommendations are taken and really appreciated! Thanks to all! Today im going to borrow my Buddy's long level and confirm that she's good to go. Fuel drain followed by the two gallon per side timed test. Question? Since I don't have the pinch off tool yet to check flow in the suspect right tank how do I know it's not going in say two gallons and not running over to the left side port and draining out? Will the right side port in level condition drain the two gallons solely? Also approximately how long would two gallons take? I suspect 5 per hour so do the math for two but I've heard 10 per our. Link to comment Share on other sites More sharing options...
Tom Baker Posted August 29, 2017 Report Share Posted August 29, 2017 1 hour ago, FredG said: Tom, in a slip, fuel will transfer. The engine will still draw from both tanks. Fred, I'm not real educated, but in my simple mind it is hard for me see how fuel can flow both ways in the line at the same time. Also I believe Flight Designs leveling means is the top of the cabin laterally, and the tunnel longitudinally. You just need to level laterally to check the ball and fuel flow. Link to comment Share on other sites More sharing options...
Tom Baker Posted August 29, 2017 Report Share Posted August 29, 2017 1 hour ago, Buckaroo said: All recommendations are taken and really appreciated! Thanks to all! Today im going to borrow my Buddy's long level and confirm that she's good to go. Fuel drain followed by the two gallon per side timed test. Question? Since I don't have the pinch off tool yet to check flow in the suspect right tank how do I know it's not going in say two gallons and not running over to the left side port and draining out? Will the right side port in level condition drain the two gallons solely? Also approximately how long would two gallons take? I suspect 5 per hour so do the math for two but I've heard 10 per our. You can test overall fuel flow, but to check each side specifically you really need to pinch off the line. Link to comment Share on other sites More sharing options...
Buckaroo Posted August 29, 2017 Author Report Share Posted August 29, 2017 I kinda suspected such! I'll wait for my wrench and do it right! By the way after sitting level all night she has 6 in right and 13 in left tank! Help!!? Link to comment Share on other sites More sharing options...
Buckaroo Posted August 29, 2017 Author Report Share Posted August 29, 2017 Gascolaror ok forgot full on valve!? Link to comment Share on other sites More sharing options...
Tom Baker Posted August 29, 2017 Report Share Posted August 29, 2017 47 minutes ago, Buckaroo said: I kinda suspected such! I'll wait for my wrench and do it right! By the way after sitting level all night she has 6 in right and 13 in left tank! Help!!? You can help the flow get started by climbing on a ladder and placing you mouth on the vent tube and gently adding some air pressure to the tank, just be careful. WARNING Never used compressed air to pressure the tank or blow out vent lines. Link to comment Share on other sites More sharing options...
Buckaroo Posted August 29, 2017 Author Report Share Posted August 29, 2017 Everything has checked out alright. Planes level and flow is about like me after six beers ? after pinching each side. The plane will now sit level in the hanger so we don't aggravate the situation. Thanks for all the help and support I'm going to trust the one side with fuel in the tube will bring me home and never let her get under 10 gallons total. Coordinated flight will be the order of the day! Link to comment Share on other sites More sharing options...
Buckaroo Posted August 29, 2017 Author Report Share Posted August 29, 2017 48 minutes ago, Tom Baker said: You can help the flow get started by climbing on a ladder and placing you mouth on the vent tube and gently adding some air pressure to the tank, just be careful. WARNING Never used compressed air to pressure the tank or blow out vent lines. I'll try this Tom thanks! Link to comment Share on other sites More sharing options...
FredG Posted August 30, 2017 Report Share Posted August 30, 2017 Tom, fair enough. But, over time the fuel levels will be lower in both tanks if the engine is running. I think that some fuel comes from both tanks (with more coming from the higher tank if in a slip). Think of it this way. Suppose that the slip is sufficient to transfer 4 gallons per hour (if the engine were not running). Now, with the engine running and burning 5 GPH (for example), the four gallons that would flow from the high wing will be consumed by the engine and the remaining gallon would be consumed from the low wing. Over time, the fuel levels in both wings will equalize, but it will be because more fuel will be burned from the high wing and less fuel burned from the low wing. Fuel isn't moving in both directions through the fuel line from the low wing, it is just being consumed more rapidly from the high wing. In that regard, you are correct. Fuel won't "transfer". But, over time, the fuel will equalize and fuel will be burned from both tanks. If, OTOH, the transfer flow was greater than engine GPH burn, then fuel would flow backwards through the fuel line to the lower tank (just as it does when the wings are not level and the engine is not running). I have no idea if that actually happens in a slip, but my guess is that if it does, the slip has to be pretty extreme. Regarding "level," I prefer to level the wings and not the top of the cabin. They may be exactly the same, I don't know. It takes more time to level the wing the way I described, for sure. My plane doesn't transfer fuel when the ball is centered and it stalls without dropping a wing. I'm gonna stick with it. Link to comment Share on other sites More sharing options...
Tom Baker Posted August 30, 2017 Report Share Posted August 30, 2017 I agree with that. Now I don't feel so stupid. Link to comment Share on other sites More sharing options...
Buckaroo Posted August 30, 2017 Author Report Share Posted August 30, 2017 Since fuel transfer is too complicated for me, I'm going to go back to the basic FD design and that is to keep it simple with no fuel selectors! I'm going to fly with lots of fuel and basically ignore the tubes! I'm going to measure before flight fuel against travel time and make sure I return with at least 10 probably 15 gallons. For me I will refill every 3 hours for insurance. During my end of 3 hour flights I will make sure my turns are completely coordinated so I keep the remaining 10 gallons against the engine! With more experience I'll probably expand these parameters some im sure. I still can't find a better LSA out there! Link to comment Share on other sites More sharing options...
Roger Lee Posted August 30, 2017 Report Share Posted August 30, 2017 Buckaroo, Fuel transfer really isn't hard. Just remember to keep fuel equal to fly 1/2 ball out to the fastest draining tank. To actually move fuel from the right wing to the left move the ball 1 complete ball out to that low fuel wing. This is all you need to know and it will always do what you want it to. Just keep it simple. Link to comment Share on other sites More sharing options...
Buckaroo Posted August 30, 2017 Author Report Share Posted August 30, 2017 Roger, I will again practice this early tomorrow and see what happens! For some reason trying this has almost negative results as in Saturday's flight. Maybe I'm pushing the rudder too hard and venting fuel? I will try this tomorrow and advise. Thanks again! It is a challenge being so far from experts! It's me and the plane only! Link to comment Share on other sites More sharing options...
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