FastEddieB Posted December 8, 2015 Report Share Posted December 8, 2015 Sounds like a good opportunity for some investigative reporting! Link to comment Share on other sites More sharing options...
IrishAl Posted December 8, 2015 Report Share Posted December 8, 2015 USA airplanes seem to be flowing at a normal pace. Are you sure about this, Andy? Wasn't it established earlier in this thread that only 16 were registered in 2014 - ? Either that's a significant slowdown in supply, or a sharp drop-off in demand....... Link to comment Share on other sites More sharing options...
Ian Posted December 8, 2015 Report Share Posted December 8, 2015 Are you sure about this, Andy? Wasn't it established earlier in this thread that only 16 were registered in 2014 - ? Either that's a significant slowdown in supply, or a sharp drop-off in demand....... I believe that there have been no new aircraft sold in the UK for the last 9+ months. I think they have priced themselves out of the market. Rather worrying in terms of on going support if this turns out to be true Link to comment Share on other sites More sharing options...
ralarcon Posted December 8, 2015 Report Share Posted December 8, 2015 Sounds like a good opportunity for some investigative reporting! Web site at Flight Design Southeast in Wilmington SC. says they have CTLSi "in stock" Cheers Link to comment Share on other sites More sharing options...
FastEddieB Posted December 8, 2015 Report Share Posted December 8, 2015 For perspective... When I bought my Sky Arrow, one positive was that 3i had been in business since the 1940's. In 2006 when I started looking for an LSA, an awful lot of the companies were relatively new and small and of uncertain future prospects, IMHO. And yet, in just a few years, 3i was mired in some form of Italian bankruptcy or reorganization- oops! I only needed parts or service from the factory three times, and that was never affected. The main downside was lack of response concerning LOA's - they just did not seem motivated to provide them. That helped push me to Experimental status. Good news is 3i was purchased by a much larger Italian company, Magnaghi. So planes and parts are still available, and there is still support. Worst case scenario, and Flight Design bellies up, good chance the assets would be picked up by someone - there are too many planes out there, so hopefully someone would see the value in the company. But regardless, making money selling GA aircraft of any description is just hard to do. Link to comment Share on other sites More sharing options...
gbigs Posted December 8, 2015 Report Share Posted December 8, 2015 The reports of my death have been greatly exaggerated. Mark Twain Link to comment Share on other sites More sharing options...
ralarcon Posted December 8, 2015 Report Share Posted December 8, 2015 Thanks for the link ! Cheers Link to comment Share on other sites More sharing options...
ralarcon Posted December 8, 2015 Report Share Posted December 8, 2015 This might be useful, perhaps . http://www.bydanjohnson.com/Sidebar.cfm?Article_ID=2038 Cheers Link to comment Share on other sites More sharing options...
Top Cat Posted December 8, 2015 Report Share Posted December 8, 2015 Flight Design delay and delivery problems... "This both sucks and blows" Bart Simpson Link to comment Share on other sites More sharing options...
FastEddieB Posted December 8, 2015 Report Share Posted December 8, 2015 This might be useful, perhaps . http://www.bydanjohnson.com/Sidebar.cfm?Article_ID=2038 Cheers Finally! Number 20!!! Woo Hoo! Link to comment Share on other sites More sharing options...
deckofficer Posted January 1, 2016 Report Share Posted January 1, 2016 As a new member to the forum I've been catching up on the posts, this thread took awhile. The reason for joining the forum is if the used market in the US doesn't change, then the FD IMHO has the best performance of any LSA that has reasonable numbers for sale. The LSA with the best performance numbers just doesn't have any used aircraft available in the US. For about the same price used for any given year, a FD and Pipistrel Virus SW are at the top of my short list. The Virus SW has the 100 hp Rotax as an option, but with LSA restrictions, the 80 hp is more than enough on such an efficient airframe. That 80 hp at 75% scoots along at 133 kt, so to be LSA compliant needs a climb prop. Fuel consumption at 133 kt is 3.59 gph, 120 kt is 3.0 gph. Rate of climb for 80 hp is 1200 fpm. If you hold a ppl and not restricted to SP, the 100 hp version 147 kt @ 75% and 1653 fpm climb. Empty weight is 632 lbs. The only used Pipistrel Virus SW currently for sale at a sweet $85K USD is in Thailand. Maybe when I'm ready to buy I'll get lucky and find one in the US. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted January 1, 2016 Report Share Posted January 1, 2016 Its hard to see how they limit the speed with a climb prop. Any details on that? I would think you would be limited to 1/2 throttle to keep from overspeeding the engine. Link to comment Share on other sites More sharing options...
FastEddieB Posted January 1, 2016 Report Share Posted January 1, 2016 Its hard to see how they limit the speed with a climb prop. Any details on that? I would think you would be limited to 1/2 throttle to keep from overspeeding the engine. And that in and of itself would limit top speed. Analogy: What effect on top speed would it have to lock a car into second gear? Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted January 1, 2016 Report Share Posted January 1, 2016 And that in and of itself would limit top speed. Analogy: What effect on top speed would it have to lock a car into second gear? Eddie, That analogy doesn't work for me. I have a motorcycle, a pickup truck and a sports car and all three reach their top speed in their 5th gear (6 speeds) or 4th gear (5 speed), as you point out they would be limited in speed in 2nd gear. As I pointed out, if we drove around in 2nd gear we would have to do it at a low throttle setting to save the engine. If we take one of our Canadian CTs with an adjustable prop we have something similar to your car transmission but where is top speed? Top speed is in the 2nd to lowest setting not the 2nd to highest like in a car. Link to comment Share on other sites More sharing options...
FastEddieB Posted January 1, 2016 Report Share Posted January 1, 2016 I still like it. Drive our Jeep in second gear and the top speed is limited by redline. Same would apply to a plane with a prop too finely pitched. Not saying its the best way. That might be to just placard a low max rpm for cruise - I believe that's how the Carbon Cub does it. Reducto ad absurdum, what would a plane's top speed be with the prop set to 0º? 1º? Also can work the other way, giving the prop so much pitch that it can't get to redline. Problem there is takeoff and climb performance left on the table. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted January 1, 2016 Report Share Posted January 1, 2016 I still like it. Drive our Jeep in second gear and the top speed is limited by redline. Same would apply to a plane with a prop too finely pitched. Not saying its the best way. That might be to just placard a low max rpm for cruise - I believe that's how the Carbon Cub does it. Reducto ad absurdum, what would a plane's top speed be with the prop set to 0º? 1º? Also can work the other way, giving the prop so much pitch that it can't get to redline. Problem there is takeoff and climb performance left on the table. Its more valid to compare flat pitch to coarse pitch than it is to compare flat pitch to a placard. There is no doubt that speed can be limited by a too flat pitch as well as a too coarse pitch the difference is one way the plane is intuitive to fly and allows for access to all of the 912's available power for cruise or even climb where the 'climb prop' option leaves the high power settings above redline so both climb and speed are limited. It is far more intuitive to take off and climb at full throttle. It is desirable to have all power available for cruise when you are limited to 92hp. Link to comment Share on other sites More sharing options...
FastEddieB Posted January 1, 2016 Report Share Posted January 1, 2016 Its more valid to compare flat pitch to coarse pitch than it is to compare flat pitch to a placard. There is no doubt that speed can be limited by a too flat pitch as well as a too coarse pitch the difference is one way the plane is intuitive to fly and allows for access to all of the 912's available power for cruise or even climb where the 'climb prop' option leaves the high power settings above redline so both climb and speed are limited. It is far more intuitive to take off and climb at full throttle. It is desirable to have all power available for cruise when you are limited to 92hp. With that, I think we are in agreement. "Its hard to see how they limit the speed with a climb prop" is the quote of yours I was addressing, and I was just trying to clarify it for the sake of others, since its relatively easy to see! Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted January 1, 2016 Report Share Posted January 1, 2016 With that, I think we are in agreement. "Its hard to see how they limit the speed with a climb prop" is the quote of yours I was addressing, and I was just trying to clarify it for the sake of others, since its relatively easy to see! Its hard to see how they limit the speed with a climb prop [given the result would be far less intuitive than limiting with a cruise prop]. I admit that either too flat or too coarse will remove access to full power (on the Virus) but still maintain that the cruise prop would be more intuitive and would have you able to take off, climb and cruise at full throttle. The 80hp version would have to get you close to LSA max speed even with an optimized prop. Link to comment Share on other sites More sharing options...
FlyingMonkey Posted January 1, 2016 Report Share Posted January 1, 2016 I have a friend with an a 582-powered Avid, and he adjusted his pitch incorrectly, making it WAY too flat. On start up the engine went to almost max RPM. It was just above idle, yet producing very little power and almost zero thrust at 6000rpm. The airplane with the brakes off would not move. Given that, surely there is *some* flat setting for any engine where the rpm will be high, yet power and thrust low, keeping the airplane from being able to go faster in cruise. Conversely, there is a setting so coarse that the engine will not develop a reasonable RPM on takeoff and climb out, hindering performance in that way. Most of our engines are adjusted somewhere near the optimal middle, but at either end of that spectrum, I'm sure we could gain performance in one regard while sacrificing the other. It's not so much that climb settings kill cruise or vice versa, just that as you adjust where the RPM bands fall at different power and prop loadings, you can still do well in one performance metric while the other goes to shite. The happy optimum is what most of us strive for, and I think that's what Roger preaches in his RPM recommendations. Link to comment Share on other sites More sharing options...
deckofficer Posted January 1, 2016 Report Share Posted January 1, 2016 This is where I get an education from the good folks here. It has been my belief (and could be wrong) that a finer pitch climb prop will allow the engine to reach peak power during take off and climb but as you level off you have to reduce throttle or you will over speed the engine. A prop with a pitch that is a compromise of good climb and cruise would be too coarse to allow peak rpm during take off and climb out, but at level flight could run at a higher throttle setting without over speeding the engine. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted January 1, 2016 Report Share Posted January 1, 2016 I have a friend with an a 582-powered Avid, and he adjusted his pitch incorrectly, making it WAY too flat. On start up the engine went to almost max RPM. It was just above idle, yet producing very little power and almost zero thrust at 6000rpm. The airplane with the brakes off would not move. Given that, surely there is *some* flat setting for any engine where the rpm will be high, yet power and thrust low, keeping the airplane from being able to go faster in cruise. Conversely, there is a setting so coarse that the engine will not develop a reasonable RPM on takeoff and climb out, hindering performance in that way. Most of our engines are adjusted somewhere near the optimal middle, but at either end of that spectrum, I'm sure we could gain performance in one regard while sacrificing the other. It's not so much that climb settings kill cruise or vice versa, just that as you adjust where the RPM bands fall at different power and prop loadings, you can still do well in one performance metric while the other goes to shite. The happy optimum is what most of us strive for, and I think that's what Roger preaches in his RPM recommendations. Most of us have gone from a coarse setting that limited power to an optimized setting that permits cruising with all power available (at some targeted altitude) and still very good climb performance even if not optimized for 5,800RPM at WOT. You speak of gaining performance in one regard while while sacrificing the other, the old climb performance vs cruise performance compromise myth. In our ground adjustable CTs, with the exception of targeting 5,800 WOT or 5,500 WOT the compromise is performance vs economy not performance vs performance. With our speed optimized props we can throttle back for economy but not as efficiently as we could with cruise props. The cruise prop gives us fine tuned economy but is unable to realize full power, quite a compromise. The reason we tend to optimize for speed in our CTs is we get best speed when we fly wide open and we still get very good economy when we throttle back. The other choice means even better economy with full power unavailable. Link to comment Share on other sites More sharing options...
FlyingMonkey Posted January 1, 2016 Report Share Posted January 1, 2016 I agree that in our normal range of adjustment, there is no need to compromise. But my example was to indicate if you really go over flat or over coarse you could keep good cruise or climb and have the other side take a dump. If you even farther either way both would probably suck. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted January 1, 2016 Report Share Posted January 1, 2016 What improves climb also improves cruise speed, they are on the same side. The only 'other side' that could 'take a dump' would be economy. It would only be a small dump because you could still throttle back even if you had to fly with a flatter pitch than is optimum for economy cruise. Link to comment Share on other sites More sharing options...
FastEddieB Posted January 1, 2016 Report Share Posted January 1, 2016 What improves climb also improves cruise speed, they are on the same side. Still beg to differ. Pitch for best continuous power - 5,500 rpm in the climb - and you will be forced to throttle back in cruise. Conversely, pitch for 5,500 rpm in level cruise, full throttle, and you will climb less well than in the case just given. But a powerful feeling of deja vú just came over me! Weird. Link to comment Share on other sites More sharing options...
Ed Cesnalis Posted January 1, 2016 Report Share Posted January 1, 2016 Still beg to differ. Pitch for best continuous power - 5,500 rpm in the climb - and you will be forced to throttle back in cruise. Conversely, pitch for 5,500 rpm in level cruise, full throttle, and you will climb less well than in the case just given. But a powerful feeling of deja vú just came over me! Weird. Granted. There is a small compromise because your engine will speed up when you level off. This compromise has to do with fine tuning a flat prop. What is often suggested here is that you want a flat prop for climb and a coarse prop for cruise speed when in reality you want a flat prop for climb and speed and a coarse prop for best economy cruise. The former is about matching WOT and max RPM which you can't do for both climb and cruise at the same pitch/altitude. The latter is about what is compromised when considering a flat vs a coarse pitch. Link to comment Share on other sites More sharing options...
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