S3flyer Posted May 7, 2013 Report Share Posted May 7, 2013 Good point -- record the prop itself along with the pitch. Anything else fellow flyers? Link to comment Share on other sites More sharing options...
sandpiper Posted May 7, 2013 Report Share Posted May 7, 2013 Just put them side by side, take off together and climb together to same altitude. Then run flat out. Determine if both have same RPM level with WOT. Don't need to set up elaborate tests. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted May 7, 2013 Report Share Posted May 7, 2013 Just put them side by side, take off together and climb together to same altitude. Then run flat out. Determine if both have same RPM level with WOT. Don't need to set up elaborate tests. True, You would need to compare engine out as well, the faster plane might have a faster air-frame. Engine out tests at matching weight but power tests with the CTLSi handicapped. Link to comment Share on other sites More sharing options...
S3flyer Posted May 7, 2013 Report Share Posted May 7, 2013 Just was going to give the 'i' the benefit of the doubt that the power curve could be statistically different. Link to comment Share on other sites More sharing options...
Ian Posted May 7, 2013 Report Share Posted May 7, 2013 And don't send a dealer (or gbigs) out to do the tests - you need someone dispassionate with neither financial nor egocentric interests in the results!!!!!!! Link to comment Share on other sites More sharing options...
sandpiper Posted May 7, 2013 Report Share Posted May 7, 2013 Put 2 identical planes side by side. One will probably be faster. Link to comment Share on other sites More sharing options...
paul m Posted May 7, 2013 Report Share Posted May 7, 2013 And don't send a dealer (or gbigs) out to do the tests - you need someone dispassionate with neither financial nor egocentric interests in the results!!!!!!! Are you kidding?...on this forum?...find someone who is dispassionate and devoid of financial and egocentric interests? How do you think we got up to 90 posts in the first place on this topic? You would think we could save that for threads on landing technique and the like. Link to comment Share on other sites More sharing options...
Sonoma Flight Center Posted May 7, 2013 Report Share Posted May 7, 2013 Thanks Dave. My observations are based on 9 hours in the injected model, from an enthusiast/pilot standpoint. I'm not one to get into a peeing contest. I run the shop full time at Sonoma Jet Center. I am privedged to be able to show and fly these marvlous airplanes when able. I also drag race my 1970 Dodge Challenger T/A. I might be able to swing a drag race if the new owner will let us. Until then, like Rodney King said "can't we all just get along!" ) Happy flying! Link to comment Share on other sites More sharing options...
Ian Posted May 7, 2013 Report Share Posted May 7, 2013 Which ever aircraft has the flatter pitched prop will win all categories here. If you introduce enough variables and resulting error you can end up proving the dynamometer wrong. That won't buy you anything but support for wild claims. Ah but CT that's where we have the advantage in Europe - a VP prop (and -12 flaps!!) - makes the measurements even more difficult LOL Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted May 7, 2013 Report Share Posted May 7, 2013 Cling to carbs, 100LL, metal and rivets, and old avionics and be left in the past. http://en.wikipedia.org/wiki/Straw_man Link to comment Share on other sites More sharing options...
Ian Posted May 7, 2013 Report Share Posted May 7, 2013 gbigs you just don't get it do you? No one denies progress - what has been taken exception to are some (or a lot) of your wild claims - I list a few: "The CTLSi will be at least 20% faster than the older 912 carbed little brother" "Fuel injection ensures the optimal mix is give to EACH cylinder in realtime, and adjusts and varys that in realtime as the flight proceeds" "fuel efficiency is not due to running lean, its due to running at a computer-real-time corrected ratio" "they squeeze more horsepower ...... out of an engine" Every one of those claims has been shown to be completely wrong. Then you say "FD making a 4-seater and using a hypbrid engine" - as far as I'm aware the engine going in the 4 seater is the Continental IO-360 AF - hardly a hybrid. Now, I'm no Luddite and I absolutely accept that things evolve (and generally improve) - my own bet is that this first implementation of fuel injection by Rotax won't be the great panacea - but at some stage they will crack it, probably with a greater re-design rather than just a bolt-on as this seems to be and at that point we may well see a significant jump in performance from a similarly sized engine and I guarantee that everyone on this forum will welcome it. For now, please, just cut down the rhetoric and stick to demonstrable truths. Once you've actually got your aircraft and got some hours in it, by all means come back and tell us just how wonderful it is (but then again we all know just how great the CTs are already!!) Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted May 7, 2013 Report Share Posted May 7, 2013 There are no wild claims for the fuel injected engine... How about these 2 that you made? Your CT will go 20% faster - ( that would take 180hp engine ) The 912iS will produce 70% less CO2 emissions - ( real number is about 18% ) Which is wilder? Link to comment Share on other sites More sharing options...
chanik Posted May 7, 2013 Report Share Posted May 7, 2013 Guys, please, just stop feeding him. I think Gbigs has more than established his, how should I say, credibility and experience level. I can't read any threads these days without half of them being refutations of the latest provocative nonsense this guy is spewing even though I have him blocked. Remember G. Carlins maxim: “Never argue with an idiot. They will only bring you down to their level and beat you with experience.” ― George Carlin Link to comment Share on other sites More sharing options...
Jim Posted May 7, 2013 Report Share Posted May 7, 2013 Personally I think Gbigs should either be refuted or banned. It seems unlikely he will ever contribute anything useful and I hate to see what appears to be inaccurate material posted on a public aviation forum. Link to comment Share on other sites More sharing options...
mocfly Posted May 7, 2013 Report Share Posted May 7, 2013 You should read some of his comments made on the video's people put on YouTube. I specifically like the one where he says and I quote "130knot speed and more avionics than a commercial jet" or "RULE #1 never believe a guy that is an expert on an engine he has NEVER flown himself" or "the CT is 60" wide 10"' wider than a cessna 172. A LARGE cockpit by any standard" Link to comment Share on other sites More sharing options...
FlyingMonkey Posted May 7, 2013 Report Share Posted May 7, 2013 My understanding is the all up weight is at least 14lb difference. Even if it is 13lb, that is a significant amount in an airplane with 1320 GW and 550lb useful load. Link to comment Share on other sites More sharing options...
markmn Posted May 8, 2013 Author Report Share Posted May 8, 2013 Yes we all could ignore him. When I first came here 99.9% of the information was good. It will only degrade the site when there is unrefuted misinformation being spewed about which will drive good members away. I would hate to see that happen. Nobody is denying the benefits of fuel injection but it is clear that the 912is is not tuned to outperform the 912 carb. I have no doubt most will opt for the injected engine when puchasing but telling a potential buyer the 912is will outperform the 912carb is untrue. As far as the side by side test we have done it with the Tecnam P2008 and the carb engine outperformed it on takeoff and climb. The cruise was similar. Testing it in the CT may give different results but i would be surprised. Nobody is denying the advantages of fuel injection. Mark Link to comment Share on other sites More sharing options...
FredG Posted May 8, 2013 Report Share Posted May 8, 2013 From Rotax web site- 912 iS 140.2 lbs (63.6 kg) 912 ULS 124.5 lbs (56.6 kg) (Difference = 15.7 lbs) (7.0 kg) From FD USA web site description of the CTLSi - "less than 22 lbs weight increase" (compared to CTls). I'm assuming the difference in engine weight and airplane weight is accounted for by the header tank and related equipment. Sorry if this is a duplication of earlier posts. Link to comment Share on other sites More sharing options...
sandpiper Posted May 8, 2013 Report Share Posted May 8, 2013 That is the bare engine/gearbox. No exhaust, etc or airframe specific components. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted May 8, 2013 Report Share Posted May 8, 2013 bigs, you just added 6 lbs by using the weight for the constant speed prop configuration. A number of posters with lots of ratings and experience have pointed out where you are wrong. We all know you can keep this up all day, or all year for that matter but where is the benefit? You have the opportunity to learn yet you try to teach first. You can't look to Rotax alone and expect to see what the additional weight of Flight Design's airframe components are too. All the new weight counts, not just what Rotax adds. Link to comment Share on other sites More sharing options...
CT4ME Posted May 10, 2013 Report Share Posted May 10, 2013 'not sure if this got posted.... efficiency testing results better than originally claimed... introduces the "eco mode" Link to comment Share on other sites More sharing options...
S3flyer Posted May 10, 2013 Report Share Posted May 10, 2013 That's what I posted to resurrect this thread --- big mistake Link to comment Share on other sites More sharing options...
Tom Baker Posted May 10, 2013 Report Share Posted May 10, 2013 gbigs, I don't think anyone has ever disputed that the 912iS gets better fuel economy. Ron in his post said he was getting 127 true at 8500, and I have seen numbers like that in both CTSW and CTLS with the 912 ULS. Here are some real world number for you to crunch. A CTSW has an empty weight of around 700-740 one of the SW's I had was 730, I've had 2 plus a LS. You could put 2x 180 pilot and passenger 110 ponds in the baggage and 20 gallons of fuel. This would let you fly for 3 hours and have 1 hour reserve. In this time you will be able to fly 360 miles. Now with your new airplane you put in the same pilot, passenger, and baggage you can only add 6.67 gallons of fuel. Even with 30% improved fuel burn you can only fly for 1 hour with less than an hour reserve and cover only 120 miles. By the way I found the SW to be just a little faster than the LS, but I never did any side by side comparison Link to comment Share on other sites More sharing options...
GlennM Posted May 11, 2013 Report Share Posted May 11, 2013 Now that I read Tom Baker's post, I don't feel so bad about my CTSW, maybe I will keep it. LOL. Link to comment Share on other sites More sharing options...
Roger Lee Posted May 11, 2013 Report Share Posted May 11, 2013 I our CT's no matter what model, weight and prop pitch are absolutely a deciding factor on over all performance. The CTLSi could be 100 lbs heavier than a few SW's (not LS's). After flying all the different CT's 100 lbs or more is everything and with 100HP engines in each it can't make up the difference. Hi Tom, With 6-7 CT's based at my field I get to do nothing, but side by side comparisons. Link to comment Share on other sites More sharing options...
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