cdarza Posted May 10, 2017 Report Share Posted May 10, 2017 3 hours ago, ausctls said: https://youtu.be/TuEdU_lrtZk Hilarious Quote Link to comment Share on other sites More sharing options...
FlyingMonkey Posted May 11, 2017 Report Share Posted May 11, 2017 2 hours ago, CTMI said: Didnt say that. Fair enough, it wasn't a trick, I just meant as your primary, go-to fuel indicator. Obviously you use all the tools at your disposal. I do too, I just have fewer of them! Quote Link to comment Share on other sites More sharing options...
FlyingMonkey Posted May 11, 2017 Report Share Posted May 11, 2017 2 hours ago, CTMI said: wowsers. Hey who here uses the AOA function on their Dynon EFIS? I would love to, but FD Germany wanted $900 for an "engineering study" to figure out how to install an AoA pitot in my CTSW. It's possible that I might revisit that at some point now that my CTSW is E-LSA, but it's still probably more trouble than it's worth. Quote Link to comment Share on other sites More sharing options...
JLang Posted May 11, 2017 Report Share Posted May 11, 2017 I gotta defend my fellow Michigander here. I think CTMI’s main point has been misrepresented, which is that the Dynon can be a useful tool *in addition to* other tools. Like any instrument or tool, the operator must understand its limitations, and also understand its failure modes. In the few months I’ve had my license, I’ve had several 4+ hr flights with no fuel stop. And since I’m 135 soaking wet, I tend to start with 30gal or more whenever I plan to be up more than 2 hrs. I figure, why not have the extra range if I end up needing it? As noted, the sight tubes don’t help above ~20 gal, so I find the Dynon useful to help confirm my flight planning assumptions about fuel usage. If after 45 min the Dynon shows 23 gal left, and my flight planning was 28 left at that point, then something is up. Perhaps it’s the Dynon itself, but I’m not going to wait for the sight tubes to show before I assume my fuel usage plan was inadequate and plan accordingly (including, in this case, trying to figure out why). Andy, I am sure you know this, since your posts convey nothing but the epitome of a conscientious pilot, but for the sake of wet-behind-the-ears folks (like me), I would not extrapolate too much confidence in your 0.2 gal accurate sight tube test. That’s a sample size of one. A characteristic of any gauge is not only accuracy, but also repeatability and reliability, under all conditions. The sight tubes are a great tool and wonderfully simple, but even with calibrated marks I think we should assume at least a few gallons uncertainty. Perhaps Tom or Roger can comment, but my suspicion is that the bend of the tubes might change slightly as they age – more of a kink at the end after time? – especially if they are cut a bit short. Quote Link to comment Share on other sites More sharing options...
CT4ME Posted May 11, 2017 Report Share Posted May 11, 2017 2 hours ago, CTMI said: wowsers. Hey who here uses the AOA function on their Dynon EFIS? I use mine. As a conservative flier, I'm almost always in the deep green, but it does start alerting me and goes to red when doing stalls. Quote Link to comment Share on other sites More sharing options...
Tom Baker Posted May 11, 2017 Report Share Posted May 11, 2017 11 hours ago, JLang said: I gotta defend my fellow Michigander here. I think CTMI’s main point has been misrepresented, which is that the Dynon can be a useful tool *in addition to* other tools. Like any instrument or tool, the operator must understand its limitations, and also understand its failure modes. I don't think there has been any mis representation. In his first post he said the sight tubes are not gauges, and the Dynon is a gauge. The simple fact is the Dynon while it is a useful tool, it is not a gauge of fuel in the tanks. It is a electronic guess of how much fuel should be in the tank based on the amount of fuel that has flowed through the fuel line to the engine. It has no way to factor in any other event that might have an effect on fuel level in the tank. The sight tubes on the other hand, are not perfect either. When the tank is full all they show is that you have more than 10.5 gallons in the tank. Once within range of the sight tube, they do a descent job of showing how much fuel is in the tanks if you know how to read them. The bottom line is once you are in flight, regardless of how inaccurate you think they are, the sight tubes are the only actual gauge of how much fuel is in the tank. Quote Link to comment Share on other sites More sharing options...
ls6pilot Posted May 11, 2017 Report Share Posted May 11, 2017 12 hours ago, FlyingMonkey said: I would love to, but FD Germany wanted $900 for an "engineering study" to figure out how to install an AoA pitot in my CTSW. It's possible that I might revisit that at some point now that my CTSW is E-LSA, but it's still probably more trouble than it's worth. http://nebula.wsimg.com/1ef3835a2c77b6b596f7809af439f75f?AccessKeyId=25B2510C35AB96A7E02E&disposition=0&alloworigin=1 This and the new ilevil beacon are pretty cool Rich Quote Link to comment Share on other sites More sharing options...
Roger Lee Posted May 11, 2017 Report Share Posted May 11, 2017 I never turned mine on. I figured if I needed that I already screwed up and should have trained myself to be better aware. I never try landing or doing any maneuver at such a slow speed or attitude to put me in that situation. It's just simple awareness. Quote Link to comment Share on other sites More sharing options...
WmInce Posted May 11, 2017 Report Share Posted May 11, 2017 35 minutes ago, Tom Baker said: The sight tubes on the other hand, are not perfect either. When the tank is full all they show is that you have more than 10.5 gallons in the tank. Once within range of the sight tube, they do a descent job of showing how much fuel is in the tanks if you know how to read them. The bottom line is once you are in flight, regardless of how inaccurate you think they are, the sight tubes are the only actual gauge of how much fuel is in the tank. Correct. After takeoff, visible fuel in the sight tubes is the only sure way to determine there is fuel in either tank. That withstanding, tank fuel can perform the "disappearing act." That happens when fuel is moved outboard of the tubes, as in a bank towards the respective tube. When that happens, a bank in the opposite direction of tank side will force the fuel to reappear in the tube (if there is any!), but the approximate quantity will not be accurate until the aircraft is back to straight and level attitude. Most here know all that. I have the Skyview "red cube" fuel flow transducer. It is a great little feature, which, when calibrated accurately, is very accurate. It is only a counting device. It requires an initial system calibration and accurate preflight input (fuel onboard before each takeoff), before it becomes a useful tool. The counter is a good tool for planning and situational awareness, but the best indicator, without a doubt, are the sight tubes. What's more, the sight tubes will probably be more reliable in detecting a hidden fuel leak (besides your eyes and nose). A few years ago, a frequent member on this forum stated, "if your sight tubes can see fuel, so can your engine." Elementary, but so, so true! It could not have been expressed any better and that is something that has stuck with me. In conclusion, the fuel system in this airplane (CTSW) should not be underestimated. It will bite you. Any pilot who flies the CTSW should have a thorough understanding of the fuel plumbing, how it works and how to manage it. Otherwise, be really familiar with glider and BRS procedures.? Quote Link to comment Share on other sites More sharing options...
CT4ME Posted May 11, 2017 Report Share Posted May 11, 2017 And it's not just the CT... Uneven fuel flow has been an issue with high-wing aircraft forever. Just Google "uneven fuel flow high wings" or throw in the word Cessna. Hundreds of thousands of hits. Oft-discussed and well-documented. I do wish FD would have documented the issue more in the manual, and placed a warning placard near the site tubes. Quote Link to comment Share on other sites More sharing options...
Tom Baker Posted May 11, 2017 Report Share Posted May 11, 2017 36 minutes ago, WmInce said: Correct. After takeoff, visible fuel in the sight tubes is the only sure way to determine there is fuel in either tank. That withstanding, tank fuel can perform the "disappearing act." That happens when fuel is moved outboard of the tubes, as in a bank towards the respective tube. When that happens, a bank in the opposite direction of tank side will force the fuel to reappear in the tube (if there is any!), but the approximate quantity will not be accurate until the aircraft is back to straight and level attitude. Most here know all that. I think it is worth pointing out that a banked turn will not cause the to move in the tank. It is slipping or skidding that causes the fuel to move. In a coordinated turn the vector acting on the fuel should be the same as it is in level flight. Quote Link to comment Share on other sites More sharing options...
FlyingMonkey Posted May 11, 2017 Report Share Posted May 11, 2017 16 hours ago, JLang said: Andy, I am sure you know this, since your posts convey nothing but the epitome of a conscientious pilot, but for the sake of wet-behind-the-ears folks (like me), I would not extrapolate too much confidence in your 0.2 gal accurate sight tube test. That’s a sample size of one. A characteristic of any gauge is not only accuracy, but also repeatability and reliability, under all conditions. The sight tubes are a great tool and wonderfully simple, but even with calibrated marks I think we should assume at least a few gallons uncertainty. Perhaps Tom or Roger can comment, but my suspicion is that the bend of the tubes might change slightly as they age – more of a kink at the end after time? – especially if they are cut a bit short. I used that one event as an illustration. I have literally hundreds of flights in the CT, using only the sight tubes. I have never made an in-flight estimate of fuel state that turned out more than a gallon or so off. As I said, if you take the time to learn how to interpret them, the tubes are plenty accurate. I carefully calibrated my tubes and my dipstick, to make sure fuel estimation would be as accurate as possible. I even accounted for parallax in my calibrations, and made my marks based on the in-flight viewing angle to the tanks, not looking straight on. I can repeat my measurements with similar accuracy to the Dynon. After all, how accurate is the fuel state you put into the Dynon when you start? Within a gallon? A half gallon? How perfectly calibrated is your flow device and k-factor setting? No measurement device is perfect, but I have very high confidence in my ability to read and interpret my tubes. I'm not saying they are better than the Dynon, but I will say in most cases they are equally accurate. Quote Link to comment Share on other sites More sharing options...
Buckaroo Posted May 11, 2017 Author Report Share Posted May 11, 2017 27 minutes ago, FlyingMonkey said: I used that one event as an illustration. I have literally hundreds of flights in the CT, using only the sight tubes. I have never made an in-flight estimate of fuel state that turned out more than a gallon or so off. As I said, if you take the time to learn how to interpret them, the tubes are plenty accurate. I carefully calibrated my tubes and my dipstick, to make sure fuel estimation would be as accurate as possible. I even accounted for parallax in my calibrations, and made my marks based on the in-flight viewing angle to the tanks, not looking straight on. I can repeat my measurements with similar accuracy to the Dynon. After all, how accurate is the fuel state you put into the Dynon when you start? Within a gallon? A half gallon? How perfectly calibrated is your flow device and k-factor setting? No measurement device is perfect, but I have very high confidence in my ability to read and interpret my tubes. I'm not saying they are better than the Dynon, but I will say in most cases they are equally accurate. I must say that after buying my plane I've had to really engage my brain again! It's a challenge for me but fun and makes life interesting again! Quote Link to comment Share on other sites More sharing options...
WmInce Posted May 11, 2017 Report Share Posted May 11, 2017 4 hours ago, Tom Baker said: I think it is worth pointing out that a banked turn will not cause the to move in the tank. It is slipping or skidding that causes the fuel to move. In a coordinated turn the vector acting on the fuel should be the same as it is in level flight. Point well taken. Quote Link to comment Share on other sites More sharing options...
JLang Posted May 11, 2017 Report Share Posted May 11, 2017 2 hours ago, FlyingMonkey said: No measurement device is perfect, but I have very high confidence in my ability to read and interpret my tubes. I'm not saying they are better than the Dynon, but I will say in most cases they are equally accurate. The point I was trying to make is that the use of one does not preclude the proper use of the other. They both do different things well. Safety-wise, it's no choice; the sight tubes are required, both legally and practically. But as optional equipment, if the Dynon is present, set it up correctly and use it -- it can provide helpful info. In my training my CFI often emphasized the importance of the instrument scan, even with VFR flight, and corroborating information from each instrument. I see this as a good example (assuming the Dynon is present), especially in turbulent conditions, or with more than 20 gal. Quote Link to comment Share on other sites More sharing options...
ctfarmer Posted May 11, 2017 Report Share Posted May 11, 2017 Another point Roger has made, so often, over time. "Fuel goes in the direction of the ball" That needs to be understood from a base perspective. Why does the ball move at all? Because you are uncoordinated - you are either slipping or skidding. The resultant gravity and g-forces on the aircraft are not acting through the center of gravity. Which is also to say, the resultant lift forces are not in line with the resultant of gravity and g forces. The ball is simply a pendulum in your aircraft. So if the ball (assuming it is accurate) is centered, in a CT with symmetrical twin tanks, your fuel balance in each tank will automatically trend towards equalization. Therefore, any existing fuel unbalance in tanks will, in that condition, level themselves in time from the hydro-static pressure differences in the tank. Same as sitting on a flat and level surface. Fuel is the same medium, in a sense, as the ball. Same forces on the pendulum. So, fundamentally, if the ball moves one way, similarly will the fuel. The magnitude of the force pushing the ball is also relevant. If the ball is way off center, the same greater forces are applied to the fuel so it will transfer faster. If you find the need to transfer fuel, do as Roger's says but understand why and and it will be an automatic deduction for eternity. Quote Link to comment Share on other sites More sharing options...
Buckaroo Posted May 11, 2017 Author Report Share Posted May 11, 2017 3 minutes ago, ctfarmer said: Another point Roger has made, so often, over time. "Fuel goes in the direction of the ball" That needs to be understood from a base perspective. Why does the ball move at all? Because you are uncoordinated - you are either slipping or skidding. The resultant gravity and g-forces on the aircraft are not acting through the center of gravity. Which is also to say, the resultant lift forces are not in line with the resultant of gravity and g forces. The ball is simply a pendulum in your aircraft. So if the ball (assuming it is accurate) is centered, in a CT with symmetrical twin tanks, your fuel balance in each tank will automatically trend towards equalization. Therefore, any existing fuel unbalance in tanks will, in that condition, level themselves in time from the hydro-static pressure differences in the tank. Same as sitting on a flat and level surface. Fuel is the same medium, in a sense, as the ball. Same forces on the pendulum. So, fundamentally, if the ball moves one way, similarly will the fuel. The magnitude of the force pushing the ball is also relevant. If the ball is way off center, the same greater forces are applied to the fuel so it will transfer faster. If you find the need to transfer fuel, do as Roger's says but understand why and and it will be an automatic deduction for eternity. Well written! Quote Link to comment Share on other sites More sharing options...
ausctls Posted May 13, 2017 Report Share Posted May 13, 2017 On 8/05/2017 at 6:26 AM, Buckaroo said: Lost my engine today at 1000 agl and landed her dead stick in a foot of alfalfa Good work landing it safely, did you attempt to restart it before landing? Quote Link to comment Share on other sites More sharing options...
Buckaroo Posted May 13, 2017 Author Report Share Posted May 13, 2017 4 hours ago, ausctls said: Good work landing it safely, did you attempt to restart it before landing? Yes I tried one quick try to no avail then turned key off and closed the fuel valve. Picking the proper field into the wind was of course the priority of the day? Thanks for asking! Quote Link to comment Share on other sites More sharing options...
ausctls Posted May 14, 2017 Report Share Posted May 14, 2017 14 hours ago, Buckaroo said: Yes I tried one quick try to no avail then turned key off and closed the fuel valve. Picking the proper field into the wind was of course the priority of the day? Thanks for asking! I wonder what may of happened if you left the fuel valve open and just activated the choke lever during your restart procedure? Quote Link to comment Share on other sites More sharing options...
Roger Lee Posted May 14, 2017 Report Share Posted May 14, 2017 The restart here should have been ball out to the left one ball, full choke and crack the throttle about 1/2" - 1". You need fuel to the carbs ASAP.. Quote Link to comment Share on other sites More sharing options...
FlyingMonkey Posted May 14, 2017 Report Share Posted May 14, 2017 I find the engine difficult to start when warm using choke. I would never think to use chocke to attempt a restart on a hot engine. Not saying it won'twork, it just runs counter to my personal experience. Quote Link to comment Share on other sites More sharing options...
Roger Lee Posted May 14, 2017 Report Share Posted May 14, 2017 Andy, The only reason to use it then is because the carbs are empty. You need fuel NOW. If the carbs were full then no choke, Opening the choke and throttle is the fastest way to fill fuel lines and carbs. More fuel flow to the problem area. Quote Link to comment Share on other sites More sharing options...
Buckaroo Posted May 14, 2017 Author Report Share Posted May 14, 2017 18 minutes ago, Roger Lee said: Andy, The only reason to use it then is because the carbs are empty. You need fuel NOW. If the carbs were full then no choke, Opening the choke and throttle is the fastest way to fill fuel lines and carbs. More fuel flow to the problem area. Yes, I wondered about the choke! Makes sense! Quote Link to comment Share on other sites More sharing options...
Doug G. Posted May 14, 2017 Report Share Posted May 14, 2017 Only makes sense if you are actually talking about a choke and not an enriching circuit. Opening the throttle defeats the use of the "choke." I also have never been able to start a warm engine with the "choke" on. I open the throttle a little and that's it. Quote Link to comment Share on other sites More sharing options...
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