Rapture

There has been discussion on this forum previously about repowering the Jabiru airframe with Rotax engines. The general consensus is that the Jabiru is an excellent airframe. However, some owners or potential owners have reservations about Jabiru engines but support the reliability of Rotax engines. Indeed, several members of the forum have already repowered their J160c or J230/J430 with the Rotax 912/914 engines. The reports on this forum from the owners of these Rotax powered Jabirus indicate that the conversions have been a success and the owners have been happy with their decisions to repower their airframes. Performance of the aircraft appears to be similar or better than the when fitted with the Jabiru engine. As many of you will be aware, the Zonsen Aero engine has striking similarities to the equivalent Rotax engine, but has not yet had enough market penetration to build up any sort of reputation for either reliability or support. While over 400 predominantly 100hp Zonsen engines have been sold into Europe, it is still a relatively new product in the US and Australia. Zonsen offers products equivalent to the Rotax range, so 80/100/115/145hp, both carbureted and fuel injected/turbocharged. Zonsen also has their own 109hp engine that fits between the Rotax 912 and 914 models. Enquiries already made to Rapture Aviation about the Zonsen range of engines indicates that there is interest in putting Zonsen engines into Jabiru airframes as the Zonsen engine will offer a savings over the equivalent Rotax product, albeit without the proven track record of Rotax. This thread is really a bit of a poll to determine what the preferred powerplant would be for the respective Jabiru models, if an owner were to consider a Zonsen engine to replace their Jabiru engine. The aircraft models that I seek opinions on are: J160c J170 J230 J430 and the engine options would be: 80hp carbureted 100hp carbureted or fuel injected (FI) 109hp carbureted or FI 115hp turbocharged 145hp carbureted and turbocharged 145hp FI and turbocharged For those that own a Jabiru or are considering owning one, I’d appreciate your opinion on which powerplant would be the best suited or most attractive option for your airframe and if possible, why that would be your engine of choice. One of the benefits that I see in a Zonsen retrofit for the J230/J430 aircraft is that when fitted with the 145hp turbocharged engine, there is not only 25hp more for takeoff, there is also 137hp cruise power available at 10,000’, 17hp more that the Jab3300 can make at sea level and full power. At the rough air limiting indicated airspeed of 112 knots at 10,000’, that equates to a 130ktas cruise for the aircraft. In still air, a 140ktas cruise speed at 10,000’ could potentially be comfortably achieved. With the FI engine, there is no carburetor heat needed and with the liquid cooling, there are no shock cooling concerns to think about. This sort of performance for a J230/J430 would help make it a better cross country aircraft. Handing over to the viewers for your feedback and opinions.

We have our first engine about to be shipped from the factory and delivery is anticipated late December/early January. If anyone is in the market for a new Rotax 912UL or 912ULS and fancies additional hp, this 109hp Zonsen CA510 engine will be available for sale. The final price will be advised once it has been delivered to our facility in Adelaide, but you could expect a saving over the lower powered 912ULS. If you might be interested in this engine, please pm me or make an enquiry through Rapture's website enquiry form. If you have a neat aircraft that would be a good showcase for the engine, we will consider sweetening the deal if you display your aircraft in the Rapture display at Ausfly 2025 (14/15 March at Wentworth) and possibly also at Avalon 2025 (25-30 March). If a customer doesn't take it, it will be going straight into one of our company aircraft that we can demonstrate. Cheers, Dave

REQUEST TO THREAD PARTICIPANTS! Could we please keep this thread on topic? The quality of Chinese products in general, whether good or bad bear no relationship to the quality of Zonsen engines. Please could we have no further mention about Chinese products in general. This thread is specifically about the Zonsen Aero engines. If you have first hand knowledge about these engines then please contribute. If you have a direct statement from someone that has first hand knowledge or experience with these engines then please contribute. Please, no politics and no bashing of other thread participants. If someone is out of order, I will ask the Admins to address it, if they haven’t already picked it up. I have counted over 30 posts in this thread that have no relevance to Zonsen engines. As I have said before, we want to make this thread one where folks can go to find useful information. Off topic chats are not useful and are an unwanted distraction. Let’s try and build this thread as a receptacle for direct knowledge about the Zonsen Aero engines. Even as the distributor, I don’t care whether the feedback is good or bad about the engines, a lot can be learned and addressed from folks problems with a product or product support that can go towards addressing the issues to make a better product, with better product support. SO PLEASE, CAN WE STOP WITH THE OFF TOPIC DISCUSSIONS AND IRRELEVANT POSTS? Thanks, Dave

We are currently obtaining a full spare parts list with prices from Zonsen. I’ll find out and PM you.

Rapture Aviation (me and my partner) is the Australian dealer for Zonsen. I think Skippy is addressing his enquiry to me.

Guys, I’d also beg you to refrain from off-topic discussions on this thread. I’m hoping that it can build to a useful and informative thread where folks can come to learn about these engines and our aircraft where the information, either good or bad can be found without having to troll through irrelevant comments. Thanks.

Thanks Nev. I have been advised by the Zonsen rep previously that their parts will fit the equivalent Rotax engine so they can be considered an aftermarket part for the Rotax engine. I will get written confirmation from Zonsen on this matter. I’ll post their response once I have it. If the information is correct and you need any parts such as rubbers, please send a message through the contact form on our website listing the Rotax part numbers and we will seek the costing and delivery time for the equivalent Rotax part.

That is for sure!

On the contrary, and I have this directly from the former CEO of Insitu, the largest drone manufacturer in the world, their biggest problem was the reliability of the powerplants in their drones. They have a $1m+ drone powered by a $50k engine. They needed the drones to be in the air continuously over the battlefields and any engine failure in ostensibly a cheap engine results in a loss of a very expensive drone and the loss of capability until another could get on station. Rotax pulled out of at least one drone market (the Bayraktar TB2 from Turkey, a big seller after the Ukraine conflict) to be replaced by someone. So someone with a Rotax type engine is now filling that space. Hours will be built rapidly and reliability will be put to the test for whatever engine this Rotax replacement might be…

Hopefully now corrected thanks Ian. Please PM me if there is anything else I need to do.

My sincere apologies Ian. I didn’t intend to break any rules. Please let me address it as you have suggested. Please PM me to discuss if I haven’t addressed it in what you consider to be a fair manner. I’d like you on-side, not off-side!

There are several good videos that have been put out by the South African distributor that explain the product range and provide some more details about the engines.

For clarity and I thought it was clear in my statement, Zonsen confirmed that the engine would physically fit on the equivalent Rotax engine mounts. I made no reference to the legality of replacing a Rotax with a Zonsen. The aircraft owner will need to ascertain that element of a potential engine swap/replacement/installation. That said, we will have no problem expressing an opinion about whether the Zonsen can be legally installed in the customers experimental/LSA/95.55 etc. That is a fairly straightforward question with back and white answers thanks to the regulatory framework.

I have confirmed that the TBO is 2,000 hours/15 calendar years, the same as Rotax. Also, I've had a few enquiries already about it being a direct drop-in replacement for the equivalent Rotax and the answer from Zonsen is yes, it will drop onto the same mounting frame as the Rotax.

All the above points and opinions have been noted. They are no different from what we (Rapture Aviation) elocuted to the Zonsen team throughout our negotiations with them for the distributorship. Zonsen are intimately aware of all these issues as well because they introduced their first aero engine product into Europe in 2019 and expanded their worldwide markets significantly in 2022. They have seen first-hand how difficult it is to break into new markets when coming up against the likes of Rotax and their embedded solid reputation. However, Zonsen is starting to make inroads as more engines get into aircraft and reliability and support are put to the test. The number of engines is still low, as are the hours, but they are building all the time. One element I discussed with Zonsen when I visited their factory was around warranty claims. There have been very few and no significant claims that I was advised of. What we intend to do is to absolutely cane a couple of engines (as suggested above, the likely 2 most desirable models) here in Australia to do our own in-the-field testing to support that which has been done at the factory and by other dealers. Of course, we will provide feedback on that to the manufacturer to assist them with product improvement which from my interaction with them is something that is important to them. For those that reach out to Rapture, we may well need to seek the response to some questions from the manufacturer as we do not have all the answers. This knowledge will come through experience with the product. We will certainly do our best at our end from the product support perspective. One question from an earlier post was about prices. With our first engine currently being delivered, we need to be absolutely certain about importation costs before we will finalise the price point and publish prices. Yes, the prices will be better than the equivalent Rotax but how much better will be determined shortly. If you might be interested to consider a Zonsen engine, please visit our website (www.raptureaviation.com) and make an enquiry through our contact form.

I will need to check on this. Thanks to your query, I can suggest to Zonsen that they include that spec in their literature, if there is such a limitation.

As a distributor trying to break a new product into a market where quality and reliability (read safety) are paramount, this is what we consider to be one of the critical elements of the “buy” decision for a potential customer. Until a product has established a reputation, either good or bad, any buyer of a product is taking a gamble and there are not too many aircraft owners that will be prepared to take a gamble. With a new unproven product, really the only way to sway buyers towards taking the risk in relation to reliability and product support is through offering a cost saving over the competition. But what is the quantum of the cost saving needed to tempt the buyer away from the tried, tested and proven product? Even in China, the cost base is at a defined level that will drive where the manufacturer needs to set their price point. These engines are slowly filtering out into the aviation market. Hours are starting to be built on them but it will likely still be a few years away before we have hard data on the reliability and product support elements of the engines. We anticipate a few lean years of breaking into the Australian market but maybe, just maybe we might end up with a product line that reduces the cost of getting our aircraft flying when compared to a Rotax, but can offer a reliable and well supported alternative. Let’s check back in 2 years time and see how things have panned out for Zonsen engines in Australia. We are sincerely hoping that the presence of these engines is a positive one in Australia.

Thanks FB. It is going to be very interesting to see how the market in Australia reacts to these engines. Only time will tell whether these engines can establish and maintain a solid reputation. Product reliability, product support and affordability will be key to any acceptance by a very critical consumer base here. I visited the factory in Chongqing, China a short while back. Zonsen has just opened their new aviation engine facility there. It was very impressive. The size of it alone was mind blowing. The very professional entrance hallway, then their corporate showroom with the history of the company, their progress over the years, their current business partners and examples of all their engines was very well displayed. I then went out back to their assembly facility. It was pristine, their technicians all professionally attired. I could have eaten off the floor it was so clean. Their warehouse was huge and automated with robots. There were shelves all the way to the very high ceiling. When parts were needed, the automated lift went down the appropriate corridor, stopped at the appropriate spot then took the container down and to the site that needed the part, then took the container back and stored it. The dispatch area had a bunch of crated engines ready to be shipped. The production line was all very neat and orderly. There was a significant quality assurance section, doing QA inspections of parts and engines. Out the back were several Dynos where their engines undergo extensive testing. The staff were all very friendly. I left with a positive feeling about their operation. I am sincerely hoping that their products and product support will ensure that there is an alternative to Rotax who do produce a great little engine. Our first engine will be delivered in December. We are looking forward to checking it out, getting it installed in an aircraft, and flying it. Fun times ahead!

Hi Everyone, For the information of all recreational flyers in Australia, Rapture Aviation of Adelaide has been appointed as the sole distributor in Australia for the full range of Zonsen Aero engines. For those that are not familiar with Zonsen Aero, they have a range of engines starting at a 12hp two stroke engine for powered parachutes and the like, through to their most powerful engine which is a 145hp fuel-injected turbocharged four stroke engine. Their 80+hp range consists of the following models: 80hp CA300 (Equivalent to the Rotax 912UL) 100hp CA500 (Equivalent to the Rotax 912ULS) 110hp CA510 (between the 912ULS and the 914) 110hp CA510i - a fuel injected version of the CA510 115hp CA520T (Equivalent to the Rotax 914UL) 115hp CA520Ti - a fuel injected version of the CA520T 145hp CA550T - a carbureted turbocharged engine 145hp CA550Ti - a fuel injected version of the CA550T (Equivalent to the Rotax 915iS) Rapture Aviation has a website at https://raptureaviation.com/ and a Facebook page at Facebook where more information can be found about the engines. Rapture Aviation is also developing the Rapture Bug single seat high performance kit aircraft. It is a modern design with its roots in the Lightning Bug kit aircraft that was produced in the early 1990's. Using updated materials and fabrication techniques, the Rapture Bug is intended to offer the same or better performance than the original Lightning Bug but offer a lot more cockpit space for taller/larger pilots, a faster Vne, and much simplified construction to get it flying sooner. At present, the new all-carbon fuselage is completed, and the new 2-piece all-carbon wings are under construction, with a target completion date for the wings of the end of the year. We hope to have the all-new, all-carbon Bug flying mid next year fitted with the 145hp Zonsen CA550Ti. This engine will offer a cruise power of around 130hp at 10,000' thanks to its turbocharging. This power setting should offer a cruise TAS of around 220ktas. Pulling the power back to a more economical power setting is projected to offer an economical cruise of 180ktas burning around 20 litres per hour. For those not familiar with the Bug, here is a photo of an original Bug, as well as one of our new fuselage taken early in its construction.

Not a dumb question at all. With our consideration being given to the 66 sq.ft. wing for the Rapture Bug, we are considering the same wing for a tandem Bug.

Yes, the Bug is a single seater. A small but steady market is all that is needed to make it a viable proposition. Through my TurbAero business, I am very close to a lot of the kit manufacturers and have a very good idea about their delivery volumes and in some cases, the margins on their kits. The advice of the manufacturers that I have received will be extremely helpful in making the determination whether a kit/RTF Bug could be a viable business. Validation of the existing flying Bugs performance would be straightforward. We have both TAS and GPS readouts to confirm our numbers. The only record of a third-party validation of the performance of a Bug was back when it was first released in the 1990s. The prototype, fitted with a 90hp two stroke engine participated in the Sun100 air race at Sun 'n fun airshow. While the Bug did not finish the race because the engine grenaded, so officially, a speed was not recorded for the Bug, it was noted that before the engine failure, it was easily overtaking the Glasairs etc that finished with a recorded average speed north of 240mph / 209 knots, with the Bug pilot noting that he was indicating around 250mph at the time of the engine failure. That said, we are building up a new build Bug from carbon that will be much lighter than the existing Bugs. It will also be tweaked for the engine installation so performance should be better than the currently flying ones. We will focus on getting verified data from that new one. As for Robin Austin's Sonerai, Robin has done an amazing job in tidying that airframe and achieving the performance that he has achieved. However, the performance that you refer to and for which it has achieved world records for is not ktas, it is knots ground speed, i.e. with wind. Robin clearly states in his write up for the aircraft (refer Sonerai World Record Plane - Robin Austin) that he achieves an honest 170 knots cruise at maximum continuous cruise power with the stock 100hp Rotax 912ULS. That would intimate a full power maximum straight and level speed in the region of 175-180 knots. Our stock Rotax 912ULS powered Bug exceeds that, but we are not comparing apples to apples because the Bug is a single seater. That is not a fair comparison. Again, I reiterate that Robin has done an amazing job on a 2 seater. The climb performance of Robin's Sonerai is also exceptionally good for a Rotax powered aircraft, also testament to his attention to drag reduction. FYI, the following text has been cut and pasted from Robin's website about his aircraft. He gives a summary of the cruise performance capabilities of his aircraft: As the speed envelope expanded, the need for an In Flight Adjustable (IFA) variable pitch propellor increased. Problem was, there are none available that suit Rotax’s low propellor RPMs and SGS's speed range. Fortunately, I became involved in the development of a brand new, IFA propeller with a leading propeller manufacturer Bolly Props Australia and was afforded a clean slate re blade design. After a year of solid engineering, development and static and dynamic testing, the prototype propeller flew. The utility of SGS was further transformed and with the new propellor and other airframe improvements it now climbed at 1920 ft per min with a maximum cruise speed of 170 knots. This speed is not particularly economical however, nor used frequently for regular cruising. Cruising speeds of 160 to 165 knots are more practical, economical and without any turbulence constraints once above 8000’. 160 knots cruise is achievable up to FL140 and provides added flexibility to stay above most weather (& yes, SGS has mixture control and oxygen). At 160 knots, engine RPM can be as low as 4600 and fuel consumption is typically 16 litres/hr depending on altitude. Cruise speeds reduce with increased loading, however even when carrying a passenger and baggage, 160 knot cruise is still practical between SL and 10,000'. That text gives some context to the true cruise capabilities of his aircraft.

Currently 196ktas with the Jab3300 and ground adjustable 2 bladed Bolly Optima Series 5 with 64” (I think but not certain without checking with the owner) diameter. Pitched for speed, static rpm is abysmal and climb rpm is not much better at 120 knots and is around 2400rpm so the Jab is way down on power in the climb, but it still climbs at circa 1500fpm. We are looking for a suitable IFA prop for it at the moment to maximise performance across the entire flight envelope. Those numbers are with Pilot and about 1/3 to 1/2 fuel. The owners Dad owns a respectable performing Lancair 360 and at the moment, both top out at about the same speed. The 360 has a constant speed prop. From 120 knots, the Bug accelerates much better than the Lancair, even with the fixed pitch prop and reduced power available at the start of the acceleration.

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.

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. 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.