Rapture Posted January 12 Share Posted January 12 Hi everyone. I know we have some very passionate aviators on this site and I’d like to gauge the potential interest in a high performance single seat ready to fly or kit LSA. The beauty of the Australian LSA regulations is that we have removed the top speed limitation, while maintaining the balance of the international LSA frameworks. Our team within Rapture Aircraft have a couple of airframes flying. We have one in Adelaide powered by a Jabiru 3300. This aircraft is currently topping out at close to 200 knots. We had one flying in the US with a Rotax 912ULS that topped out at about 186 knots, but the prop was not optimised. Photos of both aircraft are attached. This aircraft currently has a wing area of 40 sq.ft. and stalls at around 55 knots with landing flaps. As part of a project with the aircraft that we are working on, we are scaling the wing to provide an area of 66 sq.ft. One of the repercussions of doing this is that the new wing could potentially offer a stall speed that meets LSA criteria. This configuration would still offer bugger all drag at cruise speeds. We know that a Rotax 912 fits under the cowl ok, but we are thinking that a 155hp Edge Performance 912sTi would be a nice powerplant that with its turbocharging would offer excellent performance at both sea level and at altitude. A 200 knots cruise should certainly be attainable with this powerplant. The current airframes are Vne limited to 220 knots (designed for and flown to higher speeds by the original designer, but a conservative number was subsequently placed on the Vne). However, the design overhaul that is being carried out will offer a higher Vne. The ready to fly aircraft wouldn’t come cheap, particularly given the cost of the engine, but the question I have for forumites is whether in your opinion there would be legitimate interest for folks to buy a 200 knots ready to fly single seat LSA? Of course, the alternative to the high performance high cost variant is to offer a Rotax 912/Jabiru 3300 powered low cost variant that would only offer a 160-180 knot cruise. We will still plan to offer the original wing for the super high performance kit market, but with the big wing making the aircraft LSA eligible, we want to explore that market. I would appreciate your opinions or comments about the concept of a high speed single seat LSA. Dave 2 Link to comment Share on other sites More sharing options...
rgmwa Posted January 13 Share Posted January 13 I think LSA's appeal mostly to older pilots who are more concerned about their medicals and just being able to legally get into the air, rather than any particular desire to fly at 200 kts. Also, unless the USA drops their 120kt LSA limit, it's hard to see how there would be enough demand in Australia's small market to support the cost of producing such a highly optimised and relatively expensive design. Personally, I wouldn't want a single seater because I want the ability to carry a passenger or a heavier load, but that's just my preference. I would sometimes like my LSA to be able to cruise at 150kts, but I'm happy to sit on 115kts. I'll be interested to see what others think, but either way it's great to see some innovation and I hope you're successful. 2 3 Link to comment Share on other sites More sharing options...
facthunter Posted January 13 Share Posted January 13 Small Market, Can't train in it. 200 Kts is a rough ride at times. You are also getting into "Flutter' territory and where the plane can get ahead of people if they let it. LSA was a stop gap category with more traps/ limitations than benefits. Maybe go EXP VH? Nev 1 Link to comment Share on other sites More sharing options...
Rapture Posted January 13 Author Share Posted January 13 Thanks RGMWA and FH, we are already targeting experimental as our primary market, but as well as LSA, MOSAIC is likely to be introduced to the US in the not too distant future that will facilitate factory build assist or full factory build. The RTF variant could also fit into that framework in the US, opening up the market there to more completed aircraft than the experimental category now offers. An LSA variant for the Australian market would be complementary to a US MOSAIC offering. Flutter is not an issue for this aircraft. It has had a full flutter analysis completed and the flying ones are regularly flown to 220 knots and in some cases, faster for test purposes. 2 Link to comment Share on other sites More sharing options...
skippydiesel Posted January 13 Share Posted January 13 http://worldrecordplane.com/ Enough said! 1 Link to comment Share on other sites More sharing options...
kgwilson Posted January 13 Share Posted January 13 40 sq feet. Mine is 91 sq feet & I thought that was pretty small. Big difference in stall though. What's the empty weight with a 912? 1 Link to comment Share on other sites More sharing options...
Rapture Posted January 13 Author Share Posted January 13 11 minutes ago, kgwilson said: What's the empty weight with a 912? 597 lbs empty weight. 24usg fuel capacity so maximum 145 lbs fuel means 742 lbs with full fuel and no pilot. This is a heavy build airframe with 3 coats of paint and heavy steam instruments. With the new carbon airframe and EFIS, we anticipate a lot lighter empty weight for the same engine. We have set a MTOW for the current flying 912 powered airframe at 1,000 lbs. so a 258 lbs pilot and bags allowance. With the new build, we will allow a MTOW of either 1,000 lbs or 1,100 lbs (TBD) with the 40 wing and 1,200 for the 66 wing. Link to comment Share on other sites More sharing options...
Rapture Posted January 13 Author Share Posted January 13 As another data point, our Jabiru3300 powered Bug has an empty weight of 601 lbs, only 4 lbs more than the Rotax 912 Bug. Clearly, the Jabiru Bug is built lighter than the Rotax one. The new build carbon one will be lighter still by an estimated 30 lbs in basic structure. We will save more weight in the lighter panel. FYI, the nosegear retracts on the Rotax Bug to achieve its 186 ktas top speed while the Jab Bug has a fixed nosegear (more drag) and the Jab Bug also has a rough primer finish. With a smooth paint job, it will pick up another probably 15 lbs of empty weight but will have less skin friction. We anticipate that the Jab Bug will hit 200 ktas top speed with the paint job. The Jab Bug currently cruises at an economical cruise fuel flow of 20 litres per hour at a leisurely 180ktas. Compare that to the J230 that I fly occasionally where the 20 litre per hour fuel burn yields about 110-115 ktas. That indicates that the aerodynamic efficiency of the Bug is pretty good. Of course, it is a single seater but even still, its performance is impressive. Link to comment Share on other sites More sharing options...
Rapture Posted January 13 Author Share Posted January 13 Here’s a bit of a teaser. We currently have one of our flyable nosegear retractable Bugs being prepared in the US to be shipped later this month back to Adelaide. It is going to be used to assess performance with a 200+hp engine fitted. With a Vne of 220ktas on this airframe, we won’t be testing top speed but we will certainly be able to extrapolate performance out to estimate a top speed. We will also be able to determine takeoff and climb performance with the powerplant. Both are likely to be fairly impressive given that the Jab Bug at 120 kias gives a 1700fpm climb at quite reduced rpm due to the current fixed pitch prop limitations. We will have a true 200+hp available in all phases of flight for our test unit. Once we have the new build Bug available, we will transplant the powerplant into the new build where we will be able to test top speed properly. Fun times ahead. I wonder what CASA/RAAus would think of a 250 knot RAAus registered aircraft…. Anyway, more on this project in due course. The airframe is scheduled for delivery in late March then we have to fit the engine. It’ll be quiet until then on that project. Link to comment Share on other sites More sharing options...
dlegg Posted January 13 Share Posted January 13 What is the VA of the aircraft? In my 600kg max aircraft I can cruise at 115 ktas but rarely do as normally conditions can get quite rough at any time of the day. I can't imagine wanting to go at that speed in such a light plane. Link to comment Share on other sites More sharing options...
kgwilson Posted January 13 Share Posted January 13 Can't get my head around pounds but 271 kgs empty is a pretty light aircraft. I assume the brown one has the Jab 3300A in it looking at the cowl length. You'd want smooth air at 200 knots. Mins is 335kgs empty & at 120 knots the bumps can be pretty vicious. At 2000 feet and under I generally cruise at around 100knots unless it is an early morning calm air flight or I am above the weather. Link to comment Share on other sites More sharing options...
Rapture Posted January 13 Author Share Posted January 13 The aircraft has good g limits, resulting in a useful Va which from the data I have is 145 knots. I’m guessing that the low number is as a result of the negative g limit. Bear in mind that at MTOW, the wing loading is 25 lbs per sq.ft. which is high. The aircraft tolerates turbulence pretty well, thanks to the high wing loading. Still, most folks won’t want to be bumped around so a more comfortable lower speed in turbulence would help with the comfort factor, as well as being below turbulence penetration speed. What speed folks are comfortable flying around at is a very personal thing. For those that have flown military or jets, 200 knots can be agonisingly slow. I’m one of those, as are my buddies in the Rapture team. 1 Link to comment Share on other sites More sharing options...
Bosi72 Posted January 13 Share Posted January 13 9 hours ago, Rapture said: Welcome to the forum ! I see some similarities with Giles 202 aerobatic aircraft, except your aircraft has smaller rudder, or the photo could be misleading. Curious what are the spin characteristics ? As with anything in the World, if the price is right, there will be buyers. Cheers & Good luck! Link to comment Share on other sites More sharing options...
Rapture Posted January 13 Author Share Posted January 13 19 minutes ago, Bosi72 said: Welcome to the forum ! I see some similarities with Giles 202 aerobatic aircraft, except your aircraft has smaller rudder, or the photo could be misleading. Curious what are the spin characteristics ? As with anything in the World, if the price is right, there will be buyers. Cheers & Good luck! Thanks Bosi. I’ve been on this forum for a long time but under other usernames that have been appropriate to the topics that I have posted. The Bug was designed and released in kit form in 1991 well before the Giles. The Bug is not an aerobatic aircraft but it is capable of aeros. I am not aware of any spin testing that was conducted on the aircraft, but I do know that it went through a rigorous test flight regime. Unfortunately, with all the data I have on the original design, I do not have the results of the flight test schedule. When we complete the build of the new build Bug, we will look into conducting all the necessary sequences. Although the rudder looks small, it is extremely effective and it is easy to over control with the rudder, according to the pilots that fly the aircraft. 1 Link to comment Share on other sites More sharing options...
rgmwa Posted January 13 Share Posted January 13 What engine are you using that produces 200+HP? Link to comment Share on other sites More sharing options...
Rapture Posted January 13 Author Share Posted January 13 9 minutes ago, rgmwa said: What engine are you using that produces 200+HP? I can’t say at this stage but we already have the powerplant. We just need to get the airframe here to integrate it. Once that project advances a bit, I’ll write it up here with details. 1 Link to comment Share on other sites More sharing options...
pmccarthy Posted January 13 Share Posted January 13 These look like the same two aircraft that Flyvulcan was telling us about in 2010. That is 14 years ago! Link to comment Share on other sites More sharing options...
turboplanner Posted January 13 Share Posted January 13 The issue that RA is getting closer to is aircraft that get ahead of the pilot; this is an example of one. In GA you can break down injuries and fatalities into groups where the same old lessons are not learned; for example, (and by no means the lot): Pilots who don't do their checks/poor control - fuel exhaustions etc Pilots who don't get Met reports and identify severe turbulence etc - aircraft breakups, loss of control Pilots who can't navigate - fuel exhaustions, forced landings. and Pilots who learn in a 100 kt aircraft, then buy a 170 kt aircraft and go touring - incursions into restricted airspace, collisions, traffic breaches etc. And that last one is pilots who have been through a higher standard of training than RA. If you insert 200 kts into RA with its lower standard of training and less currency of pilots, the injury/fatality ratio will be higher, and stricter regulations will be needed and as with the heavier aircraft, the traditional casual flying will be squeezed out even further. Experimental is the place for this, and I don't think you would lose any customers who seriously wanted/could handle 200kts cruise with only 10% margin to VNE and the extra buffeting of the lighter mass. 1 1 Link to comment Share on other sites More sharing options...
RFguy Posted January 13 Share Posted January 13 yeah I dont see why this needs / should be in LSA category- surely VH-EXP? A Va of 145 kts implies for a 3.8g aircraft, a clean stall of at least 74 knots.... or 59 kts for 6g aero category. Sounds like quite a bit of runway required and skilled pilots. IE - like a Lanceair. Plenty of aircraft ahead of pilot incidents there There's been a couple of PA28s (suspected of) losing their wings due to a neg g manouver at high airspeed, (neg g which is a lower load factor (g limit) than pos g) . 1 Link to comment Share on other sites More sharing options...
facthunter Posted January 13 Share Posted January 13 The sheer unpleasantness of negative "G" would deter doing it intentionally but I recall hitting the roof of a Mooney with such force that if the straps had been a bit looser we would have sustained injury. This was a few kilometers downwind of a small ridge and I had said "we might geta bump here" but didn't expect it to be so violent.. Nev 1 Link to comment Share on other sites More sharing options...
Rapture Posted January 14 Author Share Posted January 14 (edited) 4 hours ago, pmccarthy said: These look like the same two aircraft that Flyvulcan was telling us about in 2010. That is 14 years ago! It is! To say that this has been a slow burn project is an understatement! I have spent the last 7 years developing a powerplant solution for the airframe (TurbAero turboprop) which I am still extremely busy with. The Bug development has taken a back seat to my full time job with TurbAero. I am now, with the help of my partner in the Bug venture pushing ahead with the Bug program through our Rapture Aircraft entity. The Bug is primarily an experimental aircraft. The 40 wing precludes it from the LSA category. The 66 wing is being considered for a very specific and one-off application for the Bug. However, one of the upsides of the big wing is that it potentially lowers the stall speed into LSA limits when flapped. So, that opens up the potential for an LSA variant, to complement the experimental variant. 2 hours ago, RFguy said: yeah I dont see why this needs / should be in LSA category- surely VH-EXP? A Va of 145 kts implies for a 3.8g aircraft, a clean stall of at least 74 knots.... or 59 kts for 6g aero category. Sounds like quite a bit of runway required and skilled pilots. The 66 wing Bug does not need to be an LSA, nor should it be an LSA, but it could be an LSA. If it meets the LSA criteria and there is an adequate market to justify offering it as a RTF option, I would have anticipated that there would be support to make it available as an LSA option. The Va of 145 is for the 40 wing Bug, I.e. the experimental variant, not the potential 66 wing LSA variant. The redesign of the Bug is enhancing the ultimate g for the airframe. This will reflect in the new Va that will need to be established for an LSA variant. The takeoff roll of the Jab3300 Bug is only about 400m so not a lot different to a Jabiru LSA. Landing is closer to 5-600m though. Concerns about speed-related safety issues have been raised as a reason for not offering it as an LSA. Learning to operate an aircraft in a higher speed envelope is alway challenging, where speed management is important. However, in the low speed regime, this aircraft would meet the LSA stall speed criteria and as such, would be the same as any LSA out there who just meet the LSA stall speed requirements. If the stall is benign with good stall warning, then the risk in this flight regime is reduced. Perhaps an angle of attack warning system could be feature of a RTF Bug to provide further comfort and awareness in this area. Attached is a photo of the new all-carbon Bug fuselage that we are building up into the new build Bug. Disregard the FWF stuff. That’s not the real nosegear, simply something added to get it onto some gear to display at Oshkosh. The new engine mount will incorporate the retractable nosegear mechanism. A new main gear will also be installed. The fuselage is sitting on a cradle that you cannot see in this photo. Edited January 14 by Rapture 1 2 Link to comment Share on other sites More sharing options...
skippydiesel Posted January 14 Share Posted January 14 I am sure there are plenty of big bore/consumption supporters out there. For myself and hopefully plenty of small bore/low consumption supporters, I question the merits of such a program. I also like speed, for its potential to save fuel - up to a point, it does not require more powerful engines/high fuel consumption - just a more efficient airframe. 1 Link to comment Share on other sites More sharing options...
facthunter Posted January 14 Share Posted January 14 (edited) Low wing loading planes will "feel" the bumps more. They don't have what used to be known as "Penetration.". To go faster in a glider you add ballast in the form of dumpable water. 200 Knots is not fast. Plenty of jets can't fly that SLOW without "droops' and some flap extended It can take about 20 miles of level flight and spoilers out and power at idle to get to flap extend speeds. IF you think about all that you can see that planning and keeping ahead of the Plane is essential . IF you are getting LOST at high speed you are getting more lost, quicker. Nev Edited January 14 by facthunter expand 2 2 Link to comment Share on other sites More sharing options...
Rapture Posted January 14 Author Share Posted January 14 14 minutes ago, skippydiesel said: I also like speed, for its potential to save fuel - up to a point, it does not require more powerful engines/high fuel consumption - just a more efficient airframe. Thats why the Rotax 912ULS and Jab3300 and the likes will be popular. 160-180 knot cruise at under 20 litres per hour. Can’t get a much more efficient airframe than that! I anticipate that the more expensive 150+hp engine options will be popular amongst the elements within the experimental community who will be seeking outright speed. Link to comment Share on other sites More sharing options...
skippydiesel Posted January 14 Share Posted January 14 "Can’t get a much more efficient airframe than that!" http://worldrecordplane.com/ Third party verification, not often part of aircraft promoters performance claims Link to comment Share on other sites More sharing options...
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