The ongoing issue of finding a replacement for leaded avgas took an ugly turn recently after Cirrus advised owners that use of anything other than an “approved” fuel would likely invalidate the engine warranty. “Per Continental and Lycoming, only approved fuels may be used for an engine to be covered by warranty. As the GAMI G100UL fuel is a non-approved fuel per Continental and Lycoming, engines known to have run this fuel may not be covered by the OEM engine warranty. For specific details, please refer to the respective Continental and Lycoming engine warranty documents,” Cirrus said in a statement. “While some aspects of the initial Cirrus testing of the GAMI G100UL fuel are encouraging, other areas, including materials compatibility, remain inconclusive.” At issue is that the GAMI fuel has not been submitted to the ASTM for “approval” but has received FAA approval in the form of a Supplemental Type Certificate that applies to virtually every spark-ignition aviation engine made.
Inside the Transatlantic Crossing of the Risen
We recently reported that the newest version of the sleek, retractable-gear Risen had made a successful transatlantic crossing. From what we could piece together from outside accounts and posts on social media, it went well. But here’s a more first-person look at the crossing, from the perspective of the right seat. Andrea Venturini accompanied designer Alberto Porto on the epic journey across the pond. Here’s his account. It all started last December, with a phone call I received from Alberto Porto. At the time, I was in Australia doing a report at the Gliding World Championship for theItalianTeam. Onthephone Alberto, designer and builder of the fastest ultralight in the world (430 kph/232 knots), with the simplicity that always distinguishes him, says: ”Andrea, keep yourself free for next June, I’ll detail everything when you return to Italy.” You can imagine my curiosity in the meantime. A few weeks later, the mystery was revealed: the Risen Superveloce with the brand new Rotax 916 iS must be brought to Oshkosh, to AirVenture, the largest and the most important aviation fair ‘of the Universe.’ I knew well what Oshkosh meant.
Risen Completes Transatlantic Leg
On June 14, a Porto Aviation’s Risen completed the transatlantic leg of its journey from Milan, Italy, to Oshkosh, Wisconsin. The company posted on social media: “We made it!!! I have been reluctant to post anything here before accomplishing this epic flight , being Italian I guess makes me more superstitious.A page in aviation history has been written by Alberto Porto and Andrea Florence (Venturini). 1900 nautical miles, average speed [of] 165 kts, with just over 43 gallons of fuel!!! We left this morning early in rainy Scotland and landed in the afternoon at Goose Bay the same day without refueling.” The company announced its cross-the-pond plans this May to bring the newly re-engined Risen to the U.S. While many versions of the retractable-gear Risen use the Rotax 912, the company had been fitting the turbocharged 915 iS. But this example has the newer, more powerful Rotax 916 iS.
Checking in With Sonex’s Mark Schaible — Update on the High Wing and Will it Be a MOSAIC Design?
Light Sport enthusiasts who appreciate light, simple, inexpensive airplanes have been watching Sonex Aircraft develop the High Wing model for a couple of years now. It’ll first come out as an Experimental/Amateur-Built version but the company is very much open to considering an E-LSA and even, with some outside help, an S-LSA version. (Or whatever we’re going to call that once MOSAIC is real.) Company owner Mark Schaible joins us to talk about the airplane’s gestation and expectations for performance and when it might fly. Hint: You’ll be able to see a cabin mockup at AirVenture this year at the least. In general, Sonex is hoping for performance similar to the low-wing Sonex designs and will be building the first example as a taildragger with a 130-hp ULPower engine. Schaible also discusses changes to the design now that MOSAIC is closer to reality. Expanded Sport Pilot rules could allow Sonex to give the High Wing a gross weight above the current 1320-pound maximum for LSA.
Chip Erwin and the TrueLite Mow the Lawn — And Then Go Flying! (UPDATED AGAIN!)
In our original post, we linked to video of the TrueLite performing taxi tests. Now it’s done better: flying! See the new videos below as Chip Erwin documents the first flights of the TrueLite happening now in Florida. Those of us looking for pure flying in lightweight form can’t help but be intrigued by the TrueLite ultralight, marketed here by Chip Erwin’s Aeromarine company. “The taxi test went fine. I didn’t have any airspeed reading so I’ll have to see what’s going on there,” Erwin says in the video. While the 36 hp Vittorazzi Cosmos 300 ran a bit hot during the taxi tests, he feels it was because it sat idling for 5 minutes before the test, saying that it cooled down once he got moving. Here’s a sampling of videos related to the TrueLite.
Crystal Balling — What Will Rotax Do Next?
Untethered prognostication is what you do waiting for the rain showers to blow through and the sun to reemerge on your long cross country. Me? I sorta do it for a living. (Such as that is.) And I get to do it often enough in front of people who work deep in the industry to see if I’ve landed close to the truth. Like playing Battleship with engineers and PR people. My latest prognostication jag centers on what’s next for Rotax. And it’s driven by a feeling that there’s no time to waste moving up the horsepower ladder. Here’s my argument. First, the traditional engine manufacturers have still not recovered from what they say are pandemic-related supply-chain issues, which causes huge delays in deliveries and helps drive prices quite high. In the Experimental realm, where I also live, new engines have become exceptionally more expensive, leading some builders to reassess their budgets and stop their projects where they stand.
Looking Back to See Ahead — Dan Johnson Recalls the Beginning of the LSA Movement
As we move toward MOSAIC as a new reality in the Light Sport/Sport Pilot world, it’s worth knowing how we got here. MOSAIC does, after all, leverage right off of the success of the LSA category. In this casual conversation, I chat with Dan Johnson about the early days of LSA and get some questions answered on how some decisions came to be made.
Amphib Dreams — Aero Adventure To Get New Leadership
Editor’s Note: This news release came across our (virtual) desks today and we feel it’s of interest to provide this update now. However, our man Dan Johnson has arranged to speak with current CEO Alex Rolinski in the next few days to get more detail on these changes and what to look for from Aero Adventure in the near future. Change is coming to Aero Adventure, maker of the Aventura amphibs. According to the company, “this month, our company will be under…new leadership. With a highly experienced and respected professional team, the company is about to enter a new era of innovation and expansion.” The company has already been making progress. “Since the beginning of 2022, we have focused on solidifying and accelerating our production process, our new team has taken us to the next level. We changed the production process, adding state-of-the-art CNC equipment. Today, we have a production capacity of 18 kits per year and plan to expand to 24 kits by 2025.” Modifications to the Aventura are on the way as well.
Reorganization Approved: Van’s Emerges From Chapter 11
While the world of LSAs is diverse enough that the trials of Van’s Aircraft, which put itself into Chapter 11 bankruptcy protection late last year, aren’t quite the foundational matters they are among the homebuilt crowd, the fact that Van’s is represented with the popular RV-12 and companies that support it are also part of the LSA ecosystem suggests more than a little spillover. In the background, Van’s has been working hard to reset its business and emerge from Chapter 11. And on May 15 the company received good news in the form of an Oregon judge approving the company’s reorganization plan. While it seemed unlikely, there was always the possibility that the court would reject or modify the company’s proposal. In the proposal, Van’s has agreed to repay unsecured creditors 55% of the money they’re owed over three years on top of an “immediate” repayment of $3350 for those in the unsecured creditor class.
Not Bent — Whisper Sling Special Prop Breaks Cover
When we last wrote about the Whisper Sling, a version of the Sling LSA used in the Sling Pilot Training Academy in Torrance, California, one teeny tiny detail was left out of the story by request. It was the next piece of the puzzle, so to speak, to reduce the airplane’s sound signature and one of the places most airframers go to help reduce noise: the prop. Not just any prop. This special “non-planar” three-blade prop designed by Craig Catto features an unusual bit of blade shape near the tips, all aimed at reducing noise while retaining or, even better, increasing efficiency. As tested on the Whisper Sling, the Catto prop showed strong thrust measurements (as seen in the video) and appears to have reduced noise, both on the ground and in the aircraft. The key to reducing noise is to control the tip vortices.
Risen Group Plans Transatlantic Flight to OSH
You’ve heard of the Risen, Alberto Porto’s sleek, fast retractable that makes the most of its Rotax 912 power. With more than 180 mph on tap with the 912 iS, the Risen seems the perfect two-person traveling machine. It’s also one, like the Sparker, that would fit well into the new MOSAIC rules. Well, Porto and Andrea Venturini are going to find out just how well it travels this summer. They’ve announced a “unique, record breaking flight across the Atlantic Ocean.” Only this Risen will be using the latest Rotax 916 iS, the turbocharged, 160-hp engine so many airframers are now fitting in place of the 915 iS. For Porto and Venturini, “the plan is to cover 3200 kms or about 2000 statute miles across the Atlantic Ocean with a fuel consumption of just over 50 gallons of fuel at speeds up to 230 mph.
There’s a New Rotax Service Center In Town: LEAF Acquired By APS
Advanced Powerplant Solutions (APS) is a new company under the new ownership of Jeremy and Daniela Knoll, who you may know of AeroSport fame, that has purchased Leading Edge Air Foils, LLC (LEAF), which, among other things, was a Rotax independent service center for the central US. APS will carry on the Rotax-oriented business from LEAF from its base in Delavan, Wisconsin. They’re based at Lake Lawn Airport (C59), about 40 miles southwest of Milwaukee and 35 miles northeast of Rockford. Joining the Knolls will be Brett Lawton, as their technical director. Jeremy and Daniela say that they are “dedicated to maintaining the legacy of LEAF while integrating innovative solutions and expanded service offerings. Customers can look forward to a comprehensive range of Rotax engines, parts, technical support, repair, and maintenance services. Our goal is to be the central hub for Rotax services in the USA, ensuring reliability, expertise, and the highest standards of customer service.” While the company is getting spooled up, maintenance classes are on hold until Fall 2024.
Watch Three Guys Talk About MOSAIC!
With the MOSAIC program now through the comment phase and in the hands of the FAA, we thought it would be a good time to recap some of its key elements and use our considerable powers of observation and prognostication to provide a little context where needed. Join me, Dan Johnson and LAMA president Scott Severen for a wide-ranging talk on MOSAIC.
MOSAIC Update & A Call For Questions
Back to Timelines
Recent reporting (for example, on AVweb) helps clarify a few things. First of all, the timeline. It was understood early on that the FAA was planning on taking 16 months to review public and industry comments, starting from the close of comments. As you probably remember, that was extended from October 2023 to January of this year. Then there was another shorter extension to fix a few “technical” issues with the original proposal, mainly relating to rules around noise and noise testing. My sources say that the FAA is unlikely to add that additional delay to the overall timeline. There was chatter early on that the FAA might have some kind of announcement at AirVenture this year, but anything beyond “yes, we’re still working on it” seems unlikely. The FAA tends not to do rulemaking in public (after the comment period, anyway), so it’s likely that we won’t hear much until we get the final rule. But that’s not the end of it. Once the FAA has published its final rule on MOSAIC, the ASTM committees may have to refine their standards based on the final rule and the FAA will need to approve it. Of course, this back-and-forth is already going on, so it’s not like the ASTM committees are working in a vacuum and no one I've talked to is predicting massive rewrites. But, according to sources, the approval process on the airframe side could take from 2 to 6 months after the rulemaking is made final. So even if the FAA and the ASTM committees are in close agreement, it still won't be an instant-on situation. Where does that get us? According to EAA’s Dick Knapinski, “It is correct that early to mid-2025 is expected to be the announcement of the final rule. We’ve been telling those who ask that, based on our conversations with the FAA, most recently at our annual winter summit in Oshkosh in early March.” But if the approval process stretches out, it could be December of 2025 before the new rules are widely in effect. Which means the biggest challenge we face with MOSAIC is mustering patience.In case you missed the broad strokes:
There’s little question we’ve covered MOSAIC extensively here on ByDanJohnson.com and have been looking ahead to a day when the proposal is a rule, sport pilots gain access to a whole raft of new aircraft, legacy LSAs have a chance to expand their operating envelopes and many of the companies planning to make new models that fit into the MOSAIC template actually come to market. Yeah, that’s a lot. And, yes, we’re all a little impatient for the FAA to make MOSAIC real. Since the comment period closed in January, there’s been plenty of industry talk and one major airshow where MOSAIC was definitely a topic of conversation. With that in mind, Dan Johnson, Scott Severen (LAMA’s president) and I are meeting next week (virtually) to catch each other up on the program—video of this meeting will post here next week. As we prepare for it, I’d like to invite you to submit questions you have and we’ll take them up during our chat.
Live (Sort Of) From Sun ‘n Fun — The Sun’s Out and Stuff’s Happening
Related Videos
https://youtu.be/OD9qE0aymwQIt’s delightfully warm and getting even better here in Lakeland, Florida, for the 50th running of the Sun ‘n Fun. What’s happening? Lots. Why haven’t you read much of it here yet? Good question. Truth is, I was stuck on the Experimental side of the situation—not a bad place to be, actually—for the first day of the show. But that doesn’t mean there isn’t news to report. Junkers unveiled its new radial-engined A50 today. I spent some time with Dynon Avionics to talk about the new 12-inch version of the SkyView HDX. (See the video I did for Kitplanes below.) And there’s much more to come, with an important opening reception tonight centered on the LSA market. Plus a few of the hardy souls who reached out with an interest to write for this site have been turning in their fine words. Sun ‘n Fun, from a working perspective, is a whirlwind.
Who Is This Guy, Anyway? Please Welcome, Marc Cook!
Ancient History
It’s easy to get bored with the details here. Let’s just say that I can remember my first flight like it was yesterday. I was maybe 10 and a friend of the family had a straight-tail Cessna 182. I was offered a ride out of Hawthorne airport in California and never even thought to say no. Why my parents didn’t put the kibosh on it I’ll never know, but I remember watching the right main tire slip away from the runway, the wheel come to a stop and a whole new set of sensations wash over me. The flight was probably no more than 15 minutes but it set a hook big enough for a Marlin. Many years later, I worked for a motorcycle magazine that succumbed to some early 1980s economics. I was young and dumb, so the severance package was a complete surprise. Still living at home and thinking nothing of being out of work, I allowed a long-simmering desire to fly come to the surface. I drove to the Long Beach airport, put all of my severance down on block time for rentals and found a CFI. From February to June I flew as often as I could, getting the private in a Cessna 150 then getting checked out in the mighty Cessna 172 and various Piper Cherokee models.Head East!
With just a few hundred hours in my logbook, I applied for a job with AOPA. I’d noticed the tiny ad in the back of the magazine, and knowing about publishing assumed that it was just a formality; they’d already found a writer but had to make an effort. I sent a resume and quickly photocopied clips expecting to hear nothing in return. I went back to my life giving it not much more thought. Until I got a call from none other than Dick Collins. Legendary as the editor of FLYING, he had recently been lured by AOPA to remake its Pilot magazine. He believed that it was important to hire young staffers who he could mold into aviation journalists. I was one of the lucky ones, accepting the offer to move to Frederick, Maryland, while still very green in the aviation realm even as I had a lot of experience in print publishing for my age. Given my rambunctiousness, I figured the job would last a year. I was there for 11. Eventually, career opportunities led me back to motorcycling, then back to airplanes again in 2004 when I was offered the big seat at KITPLANES. I got spooked by the economic issues at the end of the decade and swiveled to playing with two wheels before being lured back in 2018. I’ve been editor in chief of KITPLANES since then, and now add this website to my list of responsibilities.Where To, Then?
I have the good luck to fly a lot of different small aircraft in the course of my work and have owned four—two I built and two I bought. My first kit was a Pulsar XP in the mid-1990s, the second a Glasair Aviation Sportsman in the mid-2000s. In between, as the family grew, a Beech P35 Bonanza, which taught me the value of ongoing maintenance. I paid dearly for the previous owners’ lack of it on that Bonanza, let me tell you. My current airplane, another GlaStar, was purchased already flying. I also had casual arrangements to use aircraft as diverse as a Mooney 231 and a Socata TB-21 Trinidad TC. I don’t want to sound like the crusty old guy in the corner hangar who has seen it all—but I have seen a lot. And that makes me optimistic for the future of LSA with the coming of the MOSAIC rules package. Dan’s done a masterful job covering the project and updating you on the progress. Expanding the capabilities of LSA is a great short-term goal, making so many more airplanes available to Sport Pilots is going to do only good. But I’m most excited by the prospect of new designs—built with MOSAIC and consensus standards in mind—coming to market. When I started, the Cessna 172 was already old. And other legacy designs, like the Mooney and Bonanza models I’m so familiar with, just can’t be cost effective based on the raw labor hours required to build them. It’s going to take new thinking, like we’ve already seen among LSAs, to build out a more affordable segment of aviation, in addition to supporting the most basic, just-for-fun flying machines in the world. So bear with me as I slip into this new role. Sun ‘n Fun 2024 is going to be busy for me, a great way to get up fully up to speed on this exciting segment of aviation.Hi Folks! In case you thought you'd seen the last of me… you have not. 😎 While Marc will take over the editor duties for this website, I plan to contribute when I discover an aircraft I am sure readers will like. I've come to gain a good handle on what you love so I hope to fascinate you with new developments I find. Nonetheless, please join with me and offer a very hearty welcome to Marc Cook to the pixels of ByDanJohnson.com — becoming AffordableAviation.com. —DJ
You’re probably wondering about this raspy old voice appearing on the ByDanJohnson site. Who are you and what have you done with Dan? Part of that you already know. Dan sold this site to what was then the Flying Media Group, owned by Craig Fuller, an LSA owner himself. Since adding a bunch of marine titles from Bonnier, the overarching company is now known as Firecrown, but the aviation side is still a big part of the portfolio, including FLYING, Plane & Pilot and KITPLANES (among many others). ByDanJohnson, when it becomes Affordable Aviation, will fit like the perfect puzzle piece into the group Speaking of KITPLANES, that’s where I come from. In fact, Dan and I have history—the good kind—as he wrote about the then-nascent LSA category for KP back when all this got started. We felt it was important to get smart about the segment since it would intersect with Experimental aircraft.
Good Neighbor! — How Sling Pilot Academy Made Their Trainer Whisper
So, Whisper Sling
Necessity is the mother of invention, so the saying goes. Necessity, in this case, was success. (SPA) at the Torrance, California, airport has grown to become a training behemoth, with their fleet flying more than 4,000 hours per month, the bulk of it in the Sling two-place LSA it uses as a primary trainer. That makes the SPA one of the busiest training companies in the region. And Torrance, like many urban airports, faces increasing complaints from non-pilot neighbors; in fact, Torrance’s very existence has been threatened for decades by those opposed to the presence of airplanes at, get this, an airport. You can see where this is going. Although SPA worked hard at community outreach, noting in part that it already used aircraft that operated well under the airport’s noise limits and burned relatively little unleaded autogas (thanks to the Rotax 912 iS engines), complaints continued. At one point last year, SPA management had to fight being kicked off the airport entirely. They needed to do something to go “above and beyond” in order to keep the school running and, indeed, growing.Engineering Challenge
At this point, co-CEOs Matt Liknaitzky and Jean d’Assonville decided to undertake an ambitious engineering solution to reduce not only the actual noise footprint of Sling LSA but the quality of that sound. But we’re getting ahead of the story here. “We started by changing our procedures,” says Liknaitzky. “We then started reminding people that we had the quietest airplanes on the field. We never busted the noise monitor. But in multiple meetings with the community, we started to listen to what they were saying. They started describing the sound of our airplanes. They said it’s not that our airplanes are loud but the nature of the sound was annoying. This was a turning point for us. We told ourselves that we have to look at the sound quality, not just the quantity.” Sling then began working on solutions to making the whole installation — Rotax and Sling — less annoying. “We know that many aircraft have low-frequency sound but ours were being perceived as being buzzy, like a mosquito,” says Liknaitzky. After significant study, Sling realized that it wasn’t just the higher frequency sound the combination produces but that it wavered as well, likely the result of acoustics and the Rotax’s high-rpm nature. And they had to get on with a solution because “we’re adding 30 airplanes this year, and we already have 40 in the fleet,” says Liknaitzky. “The first thing we tried was the exhaust,” says Matt. “We added off-the-shelf glass mufflers and that made a huge difference in the sound. Then we realized you have to either add length or change the direction to reduce noise. Changing the direction has more of a backpressure penalty. We had to keep to the Rotax spec of 2.9 psi of backpressure. The standard muffler is 1.0 psi,” says Liknaitzky, so there’s some room to reduce noise even if it costs some backpressure.Keep Improving
“We iterated on the muffler: making it longer or shorter; changing the diameter,” says Matt. “We kept iterating and performing flight tests, but we also used our ears as an instrument.” The goal was to achieve something an instrument might not pick up: the quality of the noise. Eventually, the company settled on a configuration that reduced noise by 10 dbA using a long pipe that extended beneath the cabin and exited behind the wing with a distinctive “kick up.” That kick up helps place the exhaust in the wake of the wing and aim it away from neighbors on the ground. But it’s also effective in other directions. “If you were to stand behind the airplane with the engine fully revved up, you cannot hear the exhaust. All you can hear is the propeller and prop wash,” says Liknaitzky. The muffler is a simple perforated inner tube with glass packing around it. All told the muffler is 52 inches long with 40% open holes. Surprisingly, the system appears to actually improve the Sling’s performance. The company assumes that the stock Sling-built exhaust actually had too little backpressure and so the new, quieter system gives the Rotax more of what it needs. Still, testing continues. “We’ve been testing with an older airframe,” says d’Assonville, “but we’re going to be starting over with a brand new airframe. Do all the noise testing in standard configuration and then test out what we think is the final configuration. We’ll start with just the exhaust, then add the cowling modifications and then the DUC three-blade propeller.” What cowling mods, you may ask? Sling discovered that some of the noise signature came from the cowling itself, transmitting some of the acoustic energy of the Rotax through the fiberglass. In the test article, they applied a foil-backed foam sound deadening material, which substantially reduced the perceived noise level. Moreover, it helped reduce the perception of high-frequency noise, getting the company back to the goal of giving the Sling a more low-end-biased noise signature they felt neighbors would find less objectionable. “The change was remarkable,” says Matt. “It took out a lot of the jangle…it made a monster difference.” Another seemingly simple change was to alter the air exit path in the lower cowling. But forcing it to follow the lower fuselage, rather than let it vent directly downward, the sound levels were further reduced. All together, the modifications add about 10 pounds to the Sling two-seater. Sling has the advantage of being not only the user but a close relative to the factory itself, so getting approval through the ASTM process only requires a letter of authorization from the factory for testing. A similar path of the factory conducting its own testing of the modifications can lead to approval to retrofit the parts to existing airplanes and potentially to make the configuration a factory option. At this stage, the package looks like it’ll cost $3,000 to $4,000 per airplane. Testing will continue through spring and summer 2024.ARTICLE LINKS:
- Sling Pilot Academy, flight school website
- Sling LSA, information and content on this website
- The Airplane Factory USA, importer contact info and all content on this website
- The Airplane Factory, website for the South African manufacturer of the Sling series.
- Torrance, California airport, airport information website
https://www.youtube.com/watch?v=njW_CJBuuJI https://www.youtube.com/watch?v=YXAIKmpwDJ4
Harley Davidson or Rotax — Sounds can be unique and associated with a certain brand. Harley motorcycles have made their sound a trademark, defending it vigorously against wannabe knock-offs. Sling Pilot Academy found Rotax 912iS engines output a particular sound, too. However, they wanted to shield their neighbors from it. As busy as Sling Pilot Academy has become, keeping good relations is essential. So, Whisper Sling Necessity is the mother of invention, so the saying goes. Necessity, in this case, was success. (SPA) at the Torrance, California, airport has grown to become a training behemoth, with their fleet flying more than 4,000 hours per month, the bulk of it in the Sling two-place LSA it uses as a primary trainer. That makes the SPA one of the busiest training companies in the region. And Torrance, like many urban airports, faces increasing complaints from non-pilot neighbors; in fact, Torrance’s very existence has been threatened for decades by those opposed to the presence of airplanes at, get this, an airport.