Darrenr Posted August 7, 2013 Report Share Posted August 7, 2013 Went on a cross country today just round 650 nm round rip. I brought my biz partner with me and I am 6' 200 and he is 6'3 250, off topic but it is unbelievable how well we fit in that plane. Point is we don't have much useful load left so we don't top off the tanks, this plus my personal minimums are more conservative than vfr minis so we have a fuel stop midway out, at our destination, midway home and home. Midway out everything was normal, destination we burned more fuel in the right (passenger) tank than pilot side. (Not much but a few gallons). At the midway point the pilot side was down to just a few gallons but the right side only used a gallon. I thought maybe we were not flying wings level since he is heavier than I and that caused a crossover, so on the way home I focused on keeping my side slightly lower but when we landed we had the same problem. Has anyone experienced this? Link to comment Share on other sites More sharing options...
Roger Lee Posted August 7, 2013 Report Share Posted August 7, 2013 It can happen. You can have a CT that drains right or left tank faster. Left seems to be more dominant. The fuel will follow the ball. Which ever tank burns faster fly with the ball 1/2 out to that side. The drain will be more even. If you realize you allowed a tank to get really low and there is a lot in the other tank, fly with the ball out one full ball to the low tank. The engine will not only burn more fuel from the high tank, but you will be transferring fuel to the low tank. If the faster draining tank seems to go back and forth on different tanks, that may be you. Link to comment Share on other sites More sharing options...
Darrenr Posted August 7, 2013 Author Report Share Posted August 7, 2013 Thx will try, I was going to have AP check the lines? I did not try the ball, I was focused on ailerons, my mistake will try ASAP. There has always been a slight difference before but never a whole tank difference. I do long cross country's in this plane and never had that much difference is it possible there is a check valve stuck or something? Link to comment Share on other sites More sharing options...
josjonkers Posted August 7, 2013 Report Share Posted August 7, 2013 The fuel will follow the ball. Which ever tank burns faster fly with the ball 1/2 out to that side. If you realize you allowed a tank to get really low and there is a lot in the other tank, fly with the ball out one full ball to the low tank. The engine will not only burn more fuel from the high tank, but you will be transferring fuel to the low tank. This works like a charm and 10 minutes is about all it takes to even things out. Link to comment Share on other sites More sharing options...
Darrenr Posted August 7, 2013 Author Report Share Posted August 7, 2013 I will let it sit tonight should it level out in the hangar? Link to comment Share on other sites More sharing options...
Roger Lee Posted August 7, 2013 Report Share Posted August 7, 2013 There is no check valve, it is an open circuit between fuel tanks, that's why the fuel transfer works. The fuel shut off is only between the tanks and the engine. While I'm thinking of it do not park on a slant with one wing lower than the other. the fuel will transfer and may over flow out the vent. If parking on a slant put both wings so they face up hill (parallel) or down hill. I doesn't always level in the hangar especially if the difference between tanks isn't large enough. Check the next time out. Then you'll know for sure. Link to comment Share on other sites More sharing options...
Darrenr Posted August 7, 2013 Author Report Share Posted August 7, 2013 Thx! Link to comment Share on other sites More sharing options...
Darrenr Posted August 7, 2013 Author Report Share Posted August 7, 2013 What happens if u r flying and don't notice one tank drains all the way down? Will it then pull from the 2nd or if u don't use rudder input to transfer will it shutdown? Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted August 7, 2013 Report Share Posted August 7, 2013 You can run out of fuel with fuel on board. You would have to run 1 tank dry and slosh the fuel in the other tank outboard to unport it. A good rule of thumb is if you can see fuel in at least 1 sight tube so can your engine, if you cannot see fuel in either tube than adjust your rudder so that you can. If you cannot make fuel appear in either side then you need to land now. Link to comment Share on other sites More sharing options...
Darrenr Posted August 7, 2013 Author Report Share Posted August 7, 2013 Thx again Link to comment Share on other sites More sharing options...
Karl Posted August 7, 2013 Report Share Posted August 7, 2013 Went on a cross country today just round 650 nm round rip. I brought my biz partner with me and I am 6' 200 and he is 6'3 250, off topic but it is unbelievable how well we fit in that plane. Point is we don't have much useful load left so we don't top off the tanks, this plus my personal minimums are more conservative than vfr minis so we have a fuel stop midway out, at our destination, midway home and home. Midway out everything was normal, destination we burned more fuel in the right (passenger) tank than pilot side. (Not much but a few gallons). At the midway point the pilot side was down to just a few gallons but the right side only used a gallon. I thought maybe we were not flying wings level since he is heavier than I and that caused a crossover, so on the way home I focused on keeping my side slightly lower but when we landed we had the same problem. Has anyone experienced this? Link to comment Share on other sites More sharing options...
Karl Posted August 7, 2013 Report Share Posted August 7, 2013 Should try left wing higher to move fuel from left to right. Link to comment Share on other sites More sharing options...
Roger Lee Posted August 7, 2013 Report Share Posted August 7, 2013 One thing many don't know is that in an LS and SW there is a baffle half way down the tank. The LS has a little trap door to help prevent fuel from going to far out board on that tank. It allows fuel to come towards the fuselage, but only part way out board. Link to comment Share on other sites More sharing options...
sandpiper Posted August 7, 2013 Report Share Posted August 7, 2013 I don't think uneven fuel draw is unusual in high wing aircraft that have a system like ours or a selector that allows both tanks and is run on both. At least this is true of Cessnas. In the Cessna I could fix that by running on one tank or the other. And, now you can on the CTLSi. For several years the CT community bitched to FD about this but I got the impression they thought a fuel selector allowing L, R, & Both was unsafe. They either finally got the word, or the injected system required it. Anyway, to me, a header system with L, R, Both and Off is the way to go. Link to comment Share on other sites More sharing options...
Jim Meade Posted August 7, 2013 Report Share Posted August 7, 2013 I think the Cessna problem had more to do with the design of the fuel system, including where the vent was and where the crossover tube was. Remember, in an FD with Dynon, you have to verify the ball is correct before you can assume that flying with it in the center is really in the center. You can still use it as an indicator of which way the plane needs to be rigged to transfer fuel. Link to comment Share on other sites More sharing options...
Roger Lee Posted August 7, 2013 Report Share Posted August 7, 2013 A header tank with a visible sight gauge will certainly help things. FD many years ago had fuel selector valves, but there were crashes because some never bothered to switch over so they removed them. It will be interesting to revisit the selector valve in 2 years and see if any more of those crop up. It has certainly happened in the GA world. Link to comment Share on other sites More sharing options...
paul m Posted August 7, 2013 Report Share Posted August 7, 2013 There is no cockpit visible sight gauge for the header tank in the CTLSi. It does exist but it's located in the baggage compartment so not much use during flight. I'm sure over time FD will find a way to get something into the cockpit. Link to comment Share on other sites More sharing options...
sandpiper Posted August 7, 2013 Report Share Posted August 7, 2013 Doesn't the CTLSi have an in cockpit warning that fuel in the header tank is low? Link to comment Share on other sites More sharing options...
FlyingMonkey Posted August 7, 2013 Report Share Posted August 7, 2013 I have trouble reading a level in my sight tubes. They are clear and I can see the fuel level, but the level is constantly moving around a LOT. When I have ten gallons in the tank it bounces from full to empty with any movement of the plane. How long and how steady do you have to fly level to get a good read from them? Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted August 7, 2013 Report Share Posted August 7, 2013 take your hands and feet of the controls to make sure you are not the cause. on most days the fuel level will be pretty stable, when it is not you have to average what you see. do this with your ball centered Link to comment Share on other sites More sharing options...
FlyingMonkey Posted August 7, 2013 Report Share Posted August 7, 2013 I was not going straight and level for more than a minute or two, me and the wife were sightseeing. I was not surprised it was sloshing, just wondering how stable the plane needs to be to get a decent read. I do most of my flight planning by time and fuel calculations, the sight tubes are really just used to confirm I'm not losing fuel somehow or that my calculations are WAY off. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted August 7, 2013 Report Share Posted August 7, 2013 theoretically you are sightseeing doing 1 g, coordinated maneuvers and in that case the fuel should remain stable at the sight tubes. Much like Bob Hoover pouring Ice tea while barrow rolling. Link to comment Share on other sites More sharing options...
Roger Lee Posted August 7, 2013 Report Share Posted August 7, 2013 Never fly with marginal fuel and you'll never have to worry. I rarely look at the sight tubes. I look at pre-flight and if there is more than enough or I dip the tanks I don't bother to look again. Link to comment Share on other sites More sharing options...
Jim Meade Posted August 7, 2013 Report Share Posted August 7, 2013 One benefit of sight tubes is that if one has a venting or fuel line problem and loses fuel overboard, it won't show up on the Dynon fuel accumulator but you can see it on the sight tube. I bet most of us don't look at the sight tube a lot, but it's not a bad idea to glance at it periodically during a flight. Link to comment Share on other sites More sharing options...
mocfly Posted August 7, 2013 Report Share Posted August 7, 2013 Our CTSW has suffered from the same anomaly of one tank(left) using more fuel than the other, requiring a slight 1/2 ball in coordinated flight for a certain period in order to equalize the tanks. Ia am typically the one who notices due to the fact most of my trips are 3-4 hours in duration in one direction. While at Oshkosh I decided to look at some of the things that bug me about the aircraft and talk to the guys at FD about them. With regards to the fuel flow I will tell you what I did and the result that I saw on my "DIRECT" trip back home to Chattanooga. I first made sure that the wings were level. Not that difficult to do, just requires a little help, and some patience. Once I got the wings level I made sure that the control stick was in the neutral position and that all the trims were set to the centered position. Once all the trims were indicated centered I took to measuring flap, rudder and stabilator deflection. The runner was pretty well centered on the stabilator, the stabilator was very close, but the left aileron measured about 2.7 to 2.9 degrees more deflection the the right. The only thing I did was move the trim wheel until both measured within .5 degree and put a reference mark on the wheel and the corresponding area on the tunnel and never touched it on the way home. I can tell you without reservation I did not have to fly a 1/2 ball out on the entire way back to Chattanooga and the fuel differential between tanks was the lowest that I have ever seen. Maybe worth a quick check. The longest leg/time from engine start to stop is 6.1 hours. KCDW to KCHA direct 624 miles. This baby sure has some great legs. And that's without wheel pants on the mains for what it's worth. Link to comment Share on other sites More sharing options...
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