Lightwing AC4 UL versus CS-LSA and GT – choose the variant that fits your needs
After two decades of observing the development of ultralight aviation in Poland, I notice a growing interest in aircraft Lightwing AC4. The Swiss manufacturer has created a family of machines that perfectly fit the diverse needs of Polish pilots – from basic training to towing gliders.
As a distributor of leading aerospace brands, I regularly see inquiries from customers looking for the optimal solution between three AC4 variants. Each version has its own unique features that make the choice not obvious. Today we will review all three options to help you make an informed decision.
Lightwing AC4 UL – freedom of ultralight flight
The Lightwing AC4 UL is the simplest variant on offer, designed specifically for the category of ultralight aircraft with a maximum takeoff weight of 600 kg. As a pilot with many years of experience, I can confirm that this aircraft perfectly combines the advantages of LSA design with the flexibility of ultralight regulations.
The machine is equipped with a proven 100 hp Rotax 912iS Sport engine with a redundant fuel injection system. Performance is impressive – the minimum speed is 76 km/h with flaps, the maximum is 210 km/h, and the climb at full takeoff weight is as high as 4.4 m/s. I especially appreciate the fuel consumption of 9-14 liters per hour, which translates into very low operating costs.
The 1.26-meter-wide cabin provides comfort for even two-foot pilots, and the 550-liter trunk can accommodate two large suitcases. With a Junkers Magnum 601 rescue system and advanced Kanardia NESIS III avionics with two 8.4-inch touchscreens, the AC4 UL sets new standards in the ultralight category.
CS-LSA – certified European quality
The CS-LSA(Certification Specification Light Sport Aircraft) variant is a machine certified under European EASA regulations, which guarantees the highest safety and quality standards. Compared to the UL version, this aircraft offers the same basic technical parameters, but with full type certification.
The main difference is the certification process – CS-LSA undergoes much more rigorous testing and approval procedures than standard ultralights. This means higher purchase costs, but also greater assurance of quality workmanship and safe operation.
The aircraft retains its 600 kg takeoff weight, identical Rotax 912iS engine and full standard equipment. The price difference is often 10-15% over the UL version, but for many commercial operators and flight schools, the added assurance of certification is worth the investment.
AC4 GT – the power to tow gliders
The AC4 GT is the most advanced version, equipped with a turbocharged Rotax 915iSC engine with 141 hp. This additional power means not only higher performance, but above all the ability to tow gliders with a takeoff weight of up to 850 kg.
The 915iSC engine offers significantly improved performance – a power increase from 100 to 141 hp translates into a climb of 7.5 m/s (compared to 6 m/s in the basic version) and a cruising speed of 180 km/h. Top speed increases to 230 km/h, and range increases to 700 km with fuel consumption of 16 l/h.
The turbocharger system allows the engine to operate efficiently up to 23,000 feet, making the AC4 GT ideal for operations in Poland’s mountainous regions. For aeroclubs involved in glider training, it is the best available solution in this mass class.
Operating cost analysis
Comparing the operating costs of the three versions of the AC4, significant differences can be seen mainly in fuel consumption and engine maintenance costs. The AC4 UL and CS-LSA share identical economic parameters – fuel consumption of 9-14 l/h translates into an annual fuel cost of PLN 8,400-13,200, assuming 100 flight hours per year.
The AC4 GT with the 915iSC engine consumes about 16 l/h, resulting in an annual fuel cost of about PLN 15,200. In addition, the 915iSC engine has a shorter overhaul interval (1,200 hr vs. 2,000 hr), and the overhaul itself costs about PLN 120,000 compared to PLN 80,000 for the 912iS engine.
However, it is worth remembering that the AC4 GT is the only version that allows commercial glider towing, which can significantly improve operating economics by generating additional revenue.
Regulatory aspects in Poland
The Polish ultralight market is still waiting for the introduction of OPT-OUT 600 kg regulations, which would allow full use of the capabilities of these machines. Currently, the maximum takeoff weight for ultralights in Poland is 472.5 kg, which means that the AC4 UL must be operated in the K6E experimental category.
With many years of knowledge of the Polish market, I can confirm that the procedures for registering AC4s in the K6E category are well known and routinely performed by the ULC. Nevertheless, the introduction of OPT-OUT would significantly simplify the operation of these machines.
Choosing the optimal version
For primary flight schools, he recommends the AC4 UL – low operating costs, excellent piloting characteristics and ease of use make it ideal for intensive training. Glass cockpit avionics prepare students for modern aviation standards.
For commercial operators, it’s worth considering CS-LSA – full EASA certification provides greater certainty in terms of regulations and insurance. Additionally, certified machines often have a higher resale value.
For glider aeroclubs, the AC4 GT is the only sensible option. The ability to tow gliders up to 850 kg while maintaining economical operation is a unique combination on the Polish market. Alternatively, our portfolio also includes the Cessna Skyhawk or Cessna Skylane for larger towing operations.
Competition in the market
When analyzing the available alternatives, the Lightwing AC4 stands out from the competition. Comparing it to popular models like the Tecnam P2008 and Pipistrel Virus SW, the Swiss design offers greater cabin spaciousness and a higher standard of performance.
In the glider towing segment, the main competition is the older Cessna 152 or Piper PA-28, but their much higher fuel consumption (about 25-30 l/h) and maintenance costs make the AC4 GT increasingly economically attractive.
The future of the market
Observing the trends in European ultralight aviation, I foresee a further increase in the popularity of machines of the 600 kg MTOW class. Poland, despite delays in OPT-OUT implementation, is gradually catching up with Western European markets.
The growing number of pilots seeking economical alternatives to traditional GA and the development of airport infrastructure are fostering the growth of this segment. Lightwing AC4 in any version fits perfectly into these trends.
FAQ
What is the main difference between AC4 UL and CS-LSA? The main difference is the level of certification – CS-LSA undergoes full EASA certification, while UL can be registered in the simpler experimental category. The technical parameters remain identical.
Can the AC4 GT tow all types of gliders? The AC4 GT can tow gliders with a takeoff weight of up to 850 kg, which includes most modern designs. The exceptions are heavy two-seat training gliders and some high-performance models.
What credentials are needed to pilot the AC4? For the UL version, ultralight privileges (UACP) are sufficient, for CS-LSA and GT, PPL(A) or LAPL(A) privileges are needed.
Are spare parts available in Poland? Yes, as an official distributor we provide full service support and access to original Lightwing and Rotax parts in Poland.
What is the delivery time for the new aircraft? Current delivery time is 8-12 months depending on the configuration and equipment selected. I recommend reserving space in advance in the production schedule.
Summary
The Lightwing AC4 in each of its three versions represents the highest standard of Swiss aeronautical engineering tailored to different operational needs. The UL version offers the lowest operating costs while maintaining high quality, the CS-LSA provides full certification for demanding operators, and the GT opens up glider towing capabilities.
The choice between options should be dictated by the main purpose of the machine and the regulatory requirements of the specific operator. With years of experience in the industry, I can provide full support in the selection and operation process, taking advantage of our position as a leading distributor of aircraft brands in Poland.
Regardless of the choice, all versions of the AC4 guarantee Swiss quality workmanship, economical operation and excellent piloting qualities that make them an ideal choice for modern ultralight aviation in Poland.
