Tunny Posted March 18, 2014 Report Share Posted March 18, 2014 Great article in this month Plane & Pilot regarding the CTLSi. Probably the best article I've seen regarding Flight Design aircraft. The author, who fly's with the Southeast Sales Rep, provides some very enlightened information in his article, such as; fuel consumption vs. speed numbers. Myself, flying both LSA and a high performance complex aircraft, I believe these are more "real world" than some of the numbers I've seen thrown around on the internet. Link to comment Share on other sites More sharing options...
FredG Posted March 18, 2014 Report Share Posted March 18, 2014 Nice article, I agree. One very small point, the author wrote "Seats are laterally adjustable". Is this correct? I thought lateral means to the side. Aren't the seats adjustable fore and aft? Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted March 18, 2014 Report Share Posted March 18, 2014 Please post a link or the speed/performance numbers. Link to comment Share on other sites More sharing options...
S3flyer Posted March 18, 2014 Report Share Posted March 18, 2014 http://www.planeandpilotmag.com/aircraft/pilot-reports/flight-design/the-i-s-have-it.html Eco mode delivered about 107 knots at four gph, while 75% power yielded about 119 knots at a 6.5 gph burn. Boucher prefers the sweet spot in the middle: about 114 knots at a fuel flow of 4.5 gph. "To burn two extra gallons per hour for three or four knots is not really worth it," he said. These performance numbers don't appear to be materially different than those I've seen with the ULS either in fuel consumption or cruise. Link to comment Share on other sites More sharing options...
Duane Jefts Posted March 18, 2014 Report Share Posted March 18, 2014 Having flown numerous flights in loose formation with CT's, my experience shows that the CTLSi burns .8 gph less on the average at 110kts. If you back it off to 100kts the savings is closer to 1.0 gph. Link to comment Share on other sites More sharing options...
ralarcon Posted March 18, 2014 Report Share Posted March 18, 2014 http://www.planeandpilotmag.com/aircraft/pilot-reports/flight-design/the-i-s-have-it.html These performance numbers don't appear to be materially different than those I've seen with the ULS either in fuel consumption or cruise. I can attest to that. Cheers Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted March 18, 2014 Report Share Posted March 18, 2014 6.5pgh @ 75% sounds wrong to me. I'm pretty sure I burn less with my ULS. Link to comment Share on other sites More sharing options...
FlyingMonkey Posted March 19, 2014 Report Share Posted March 19, 2014 6.5pgh @ 75% sounds wrong to me. I'm pretty sure I burn less with my ULS. 6.5gph sounds like more of a flat out number, not 75%. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted March 19, 2014 Report Share Posted March 19, 2014 6.5gph sounds like more of a flat out number, not 75%. Right which makes this statement wrong ""To burn two extra gallons per hour for three or four knots is not really worth it," he said. " Link to comment Share on other sites More sharing options...
josjonkers Posted March 19, 2014 Report Share Posted March 19, 2014 6.5pgh @ 75% sounds wrong to me. I'm pretty sure I burn less with my ULS. Absolutly! I know for a fact that is about 1 to 1.5gph too high. Link to comment Share on other sites More sharing options...
Anticept Posted March 19, 2014 Report Share Posted March 19, 2014 6.5 gph at full throttle maybe. I suspect there is something that is misconfigured on the plane they are using. Link to comment Share on other sites More sharing options...
cdarza Posted March 19, 2014 Report Share Posted March 19, 2014 i always compute 7 gallons per hour for flight planning. (just to be safe) everytime i land and check, i am pleasantly surprised with a 5 gallon burn @ roughly 75% power. ULS Link to comment Share on other sites More sharing options...
FlyingMonkey Posted March 19, 2014 Report Share Posted March 19, 2014 i always compute 7 gallons per hour for flight planning. (just to be safe) everytime i land and check, i am pleasantly surprised with a 5 gallon burn @ roughly 75% power. ULS Hmm...if you always burn 5gal, why plan for 7? Wouldn't you rather be correct and accurate and just land with whatever reserve you are comfortable with? You are flight planning almost 50% additional fuel burn that doesn't exist, and leaving about 30% of your range on the table. Link to comment Share on other sites More sharing options...
FastEddieB Posted March 19, 2014 Report Share Posted March 19, 2014 Andy, I suspect it's the same mentality that has some setting their watches ahead so that they have a "cushion". Similarly, some Cirrus pilots routinely plug in less than full fuel when they top off. I'm probably like you in that we enjoy accuracy. Others enjoy the "fudge factor". And never the twain shall meet. Incidentally, my Sky Arrow holds 17.8 usable and cruises at about 95k. I used to throttle back a bit and try for 3 hour legs. After a couple of nerve wracking legs with the gauge indicating 1/8 tank and the LOW FUEL light pestering me, I now aim for legs of about 2 hours, figuring even @ 6 gph I'll land with an hour or so in the tank. When flight planning, I tend to look for airports no more than 200 to 250 nm away for each leg. Upsides? Lots of landing practice and we get to meet a lot of friendly people on cross countries. Not to say I'm not a little jealous of the CT's speed and range. But just a little. Link to comment Share on other sites More sharing options...
Anticept Posted March 19, 2014 Report Share Posted March 19, 2014 Eddie: Install a removable tank in the back seat or cargo bay. Link to comment Share on other sites More sharing options...
Tom Baker Posted March 19, 2014 Report Share Posted March 19, 2014 I have flown the airplane that they reviewed for just a little bit. I don't remember seeing 6.5, but I did see 4.5 at 5200 rpm at about 113-115 true. I think the prop had to much pitch. The airplane had a longer take off roll and initial climb was less than my CTLS. Link to comment Share on other sites More sharing options...
coppercity Posted March 19, 2014 Report Share Posted March 19, 2014 Upsides? Lots of landing practice and we get to meet a lot of friendly people on cross countries. Not to say I'm not a little jealous of the CT's speed and range. But just a little. Plus your bladder never feels like its going to explode after 6hrs in the air! Link to comment Share on other sites More sharing options...
Jacques Posted March 19, 2014 Report Share Posted March 19, 2014 but you can pee in flight..but not refuel my range is (was) 7.5 hours with the 80 hp ...5000/108 kts 7 w reserve for sure the 912iS use less fuel but we have to fly A LOT to see the real economy Link to comment Share on other sites More sharing options...
Anticept Posted March 19, 2014 Report Share Posted March 19, 2014 What, you don't have a KC-135 loaded with mogas on speed dial? Pfffft amateurs... Link to comment Share on other sites More sharing options...
FlyingMonkey Posted March 19, 2014 Report Share Posted March 19, 2014 but you can pee in flight..but not refuel my range is (was) 7.5 hours with the 80 hp ...5000/108 kts 7 w reserve for sure the 912iS use less fuel but we have to fly A LOT to see the real economy And I think that is exactly the sticking point for most of us. What is the break even point for the additional $6k that the injected motor costs in fuel savings, saving maybe 1 gph? It's probably longer than the 2000hr TBO of the engine! I'm sure there are other subtle advantages of the injected engine, but many seem to be reaching the conclusion that the 912S/ULS is very much "good enough" and they can't justify the additional expense when the carb'ed engine is already nearly $20k. It might make some more sense in an airplane with a 12-15 gallon fuel tank where the fuel savings equates to a sizable portion of total range, but not so much in the 34 gallon CT. Link to comment Share on other sites More sharing options...
Jacques Posted March 19, 2014 Report Share Posted March 19, 2014 What, you don't have a KC-135 loaded with mogas on speed dial? I had one..but resold it when I realized I can't put skis on. Link to comment Share on other sites More sharing options...
207WF Posted March 30, 2014 Report Share Posted March 30, 2014 At an altitude where 75% is full throttle, I might burn 6 gph in my ULS, but that would be because I am too rich with the carbs. I thought the fuel injection was going to fix that. WF Link to comment Share on other sites More sharing options...
Roger Lee Posted March 30, 2014 Report Share Posted March 30, 2014 The 912is does fix that. I just flew along side a CTLSi over Phoenix at 9500. My fuel burn was over 1 gph more and I used more rpm to fly along side. At the lower altitudes I was using less fuel. My 5200 rpm was his 5300 rpm which puts him over the 92% throttle position economy mode. The fuel injection does a much better job than the carbs at higher altitudes. My EGT's were 1250F and his were 1440F. Much better fuel management. If you attend Sun'n Fun you will hear a new Rotax (secret society stuff) announcement about the 912is engine. It will benefit all users current and future. You'll like it, trust me. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted March 30, 2014 Report Share Posted March 30, 2014 At an altitude where 75% is full throttle, I might burn 6 gph in my ULS, but that would be because I am too rich with the carbs. I thought the fuel injection was going to fix that. WF I think I am closer to 5. Its true we are full rich but there is less air. Link to comment Share on other sites More sharing options...
Runtoeat Posted March 31, 2014 Report Share Posted March 31, 2014 My friend with a 2008 CTLS keeps detailed records regarding fuel usage. I'll see what he shows. My recollection is cruise @ 75% we run at 113 to 115 kts and burn 4.5 to 5 gal/hr. At WOT, which is 120kt, we use 5.0 to 5.5 gal/hr. I'll check. We are both pitched for 5600 to 5700 rpm @ WOT and altitudes flown are typically 3000 MSL or less. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.