Sky Power GmbH decided in favor of Ersa soldering tools

The German UAS-engine manufacturer Sky Power is refining its production, and in this context has put Ersa soldering tools into operation. These are used in the in-house electronics workshop.


The new soldering tools are Ersa i-CON 1 soldering stations with integrated solder fume extraction. These are used for the conversion of ignition systems and other electronics. “Since to a large extent we configure and manufacture propulsion systems according to customers wishes, we must provide some of our systems for example with new, longer cables. We perform these conversion measures ourselves in-house, which is why we were searching for a versatile complete system, that can be used for a variety of tasks”, stated Karl Schudt, CEO of Sky Power GmbH. For today’s UAS systems, reliable electronics play a decisive role. “Today’s applications are flying computer systems. The electronics must therefore function reliably. Our engines and the associated control systems are subjected to different, in some cases extreme temperature conditions and high rates of acceleration. Here the solder joint is therefore given special attention”, declared Schudt.


The i-CON 1 is an electronically controlled system. The digital soldering station is equipped with the ergonomic and powerful 150 W i-TOOL soldering iron, on which different soldering tips can be mounted very easily. For Sky Power this was particularly important, in order to be able to react flexibly to future requirements. The soldering iron is equipped with a motion sensor, which switches the system to an energy-saving and tip-sparing standby mode when not in use. The easy operation is ensured through the intuitive one-touch control and the large multifunctional display of the station. The user is notified by an optical information when the optimal process window is reached. Furthermore, the i-CON 1 has been equipped with a solder fume extraction unit.


“Sky Power is a very interesting customer for us, as we have been observing the industry for unmanned systems for a very long time. In particular the use of drones is a field of application, that will continue to grow strongly in future. It is therefore important for us, to collaborate with one of the leading engine manufacturers in this branch”, declared Jörg Nolte, Product Manager for Soldering Tools, Rework and Inspection Systems at Ersa.

Following the recently presented SP-110 FI TS, Sky Power GmbH starts 2019 with another new product and presents the second newly developed 2-stroke engine. The SP-210 FI TS is based on the same engine concept and optionally can also be offered without system carrier.


The newly developed SP-210 FI TS with max. 8,2 kW at 5000 rpm has a system carrier, just like the SP-110 FI TS. This is mounted above the cylinders with the two electronic systems of the HKZ215 ignition and also the engine injection system. The injection system as well as the system carrier are screwed firmly together with the engine. All data lines of the sensors, which gather engine data at a variety of measuring points and transmit these to the ECU030, are bundled on the system carrier. In the event of faults the system carrier can be dismantled complete, together with the injection system. A new system carrier with all modules and data cables can then be mounted and screwed together. Due to the passive ignition system, which is controlled by the ECU030, the engine is operational again after just a few minutes. “Consequently, the engine is extremely user- and maintenance friendly”, explained Karl Schudt, CEO of Sky Power GmbH. The engine is equipped with plug connectors from racing as standard. Plug connectors according to MIL specifications are possible as an option. At the request of the customer, the system carrier can also be left out, whereby longer cables are required and the integration of the engine is more complex.


As with the SP-110 FI TS, special attention was also given to extremely smooth running of the SP-210 FI TS. In addition, the objective was to achieve a fuel consumption as low as possible. “Just like with the SP-110 FI TS, our theoretical calculations proved to be true. The dynamometer tests verified the fuel requirement specified by us. At 5000 rpm this is about 480 gr/HP/hour. Consequently, with this engine we will also satisfy the demands of our customers, who are searching for efficient and fuel-saving drive solutions”, declared Schudt happily. The SP-210 FI TS is available as petrol engine. A Heavy Fuel (HF) variant will follow in the middle of 2019.

Sky Power GmbH introduced itself to the specialist public for the first time at this year’s AUVSI Xponential in Denver. Since then a series of new engines has been developed for a wide variety of Unmanned Aerial System applications (UAS). Now, with the newly developed 110 ccm engine, SP-110 FI TS, a completely new engine concept is presented, which focuses squarely on performance- and fuel optimization, ease of maintenance and space saving.

“Sky Power has dedicated itself to the development of high-performance engines based on 2-stroke and Wankel engine technology, that are used in demanding UAS applications. For this reason, we have optimized the existing SP-110 FI TS yet again, in order to make it even more efficient for the future tasks of our customers”, declared Karl Schudt, CEO of Sky Power GmbH. This not only includes the engine performance, but also the engine design.

The newly developed SP-110 FI TS has a system carrier, which is mounted above the two cylinders. Besides the two electronic systems of the HKZ215 ignition, the engine injection system is also mounted on this system carrier. Both the injection system as well as the system carrier are screwed firmly together with the engine. All data lines of the sensors, which gather engine data at a variety of measuring points and transmit these to the ECU030, are bundled on the system carrier. “The system carrier is fixed to the engine with screws. If faults occur, this can be completely dismantled together with the injection system. To do this, the screws and all plug connections are detached. A new system carrier with all modules and data cables can then be mounted and screwed together. As a result the engine is operational again after just a few minutes, since the ignition system is passive and is controlled by the ECU”, explained Schudt. Plug connectors from racing were chosen for the data cables. Plug connectors according to MIL specifications are also possible. “At the request of the customer, the system carrier can also be left out. In that case, all systems are positioned in the UAS body, whereby longer cables are required and the integration of the engine is more complex”, stated Schudt.

Engine, system carrier and all electronic modules thus form a compact unit, that can be installed in the UAS, thereby saving space. In addition, the engine performances and the smooth running were further optimized. The latter is important, especially for land survey or reconnaissance flights. The improved engine performances are dependent on the muffler and propellers and were determined on a dynamometer test rig. Particular attention was thereby given to a reduced fuel consumption, in order to make the operation of the UAS even more efficient. Due to the newly developed ECU030 and the new HKZ215 ignition, the development team already knew in advance, that fuel savings of 20% and more are possible. “This trend proved to be true. We were able to save a further 5%, dependent on the speed, as the dynamometer tests verified. Consequently, we will meet the current and future requirements of our customers, who are looking for efficient and fuel-saving drive solutions, in order to increase their range, the flying time or the payload”, stated Schudt happily.

The SP-110 FI TS is available as petrol engine. A Heavy Fuel (HF) variant will follow in the middle of 2019. “We are working on a new, lighter HF system, that besides the reduction in weight, also has a reduced fuel consumption of the HF engine as objective”, declared Schudt looking ahead.

If you need more information please contact the sales team.

Due to the growing number of inquiries concerning complete drive units for Unmanned Aerial Systems (UAS), the German manufacturer of 2-stroke and Wankel engines, Sky Power GmbH, has intensified its cooperation with Mejzlik Propeller from the Czech Republic. The objective is the development of propellers coordinated individually to the engine and the customer application.

“In past projects we were approached again and again by our customers for propeller recommendations. Since we develop complete drive units for our customers that are coordinated to the customer application, the requests on the part of the customers were understandable. Since we didn’t want to set up our own propeller development department, we looked around for a partner who had the same understanding of quality as us”, declared Karl Schudt, Managing Partner of Sky Power GmbH. Sky Power choses Mejzlik Propeller from the Czech Republic. “We had already worked well together in the past and were convinced of the quality of carbon fiber propellers”, elaborated Schudt.

In the world of unmanned aviation, Mejzlik Propeller is well known for its work. All propellers are manufactured from carbon fiber and can be adapted in a variety of features, forms and designs of the customer application and the outputs to be achieved. Besides the size and the pitch, the number of blades, the weight, the carbon fiber material as well as the surface can also be adapted. “The propeller must perfectly match the engine, as only this way can an efficient utilization of the entire drive unit be ensured”, explained Jan Hruška, Business Development Manager at Mejzlik Propeller.

Furthermore, at Mejzlik Propeller particular attention is paid to the quality. “Our customers sometimes move sums running into millions in the air, if one counts the UAS and the payload together. Apart from this, in future flying over groups of people will become routine. Flying must therefore be absolutely safe. For this reason, the quality of the propeller must be given special attention, in order to ensure safe flying”, stressed Hruška. That’s why various propeller tests are carried out before delivery. Besides a balance tests, an inner structure tests, an optional RPM tests and a visual quality inspection are performed.

Apart from that, for Sky Power there was a further incentive for the cooperation. Since every engine is coordinated to the customer specifications, so-called propeller curves are required. “Very few propeller manufacturers can provide these, as the tests are complex”, stated Schudt knowingly. The velocity, the flight altitude, the rotational speed as well as the environmental conditions influence the performance of a propeller and consequently also that of the entire propulsion unit. “Based on these details and the computation models, we can calculate and develop the right propeller for every application”. To design an appropriate propeller, we also consider the data that we already have from the propellers previously designed and measured. Based on these measurements and our experience, we can adapt the design to your requirements and give you a basic idea, how the respective propeller behaves”, confirmed Hruška. And Schudt added: “This experience is important for us, in order to provide our customers with a perfectly coordinated drive unit. Because this is what our customers expect”.

Both companies will in future work more closely together on customer projects.

“In individual projects, we will fall back on the experience of our Czech colleagues very early on, if our customers also want to adopt this approach”, stated Schudt. In this case the customer can expect a complete solution from a single source.


If you need more information or more propeller details, please contact the sales team.

3W-International’s performance partner Sky Power has also brought a new injection and ignition system to market, which can be used for all 3W gasoline and heavy fuel (HF) engines. The new systems are obtainable immediately. The conversion of engines already in use is also being offered. The objective was to massively reduce the engines’ consumption.

“The efficient use of UASs is becoming increasingly important for our customers. That’s why we as engine manufacturers are interested in a reduction of fuel consumption”, explains Karl Schudt, managing director of Sky Power GmbH. Exhaust, ambient air, and engine temperatures as well as air pressure can influence fuel consumption. So, these parameters must be permanently controlled to control the engine efficiently”, continues Schudt. “The optimization of engine management was therefore one of the new development’s goals.”

Sky Power’s new injection system for engines from 3W-International is called ECU030. The universally applicable electronic injection system is usable for both gasoline mixtures and HF applications. Four ignition channels with two separately settable injections nozzles ignite the fuel mixture. Pump pressure is controlled electronically here. A cold start function for the engine is also integrated. The automatic controller adjusts the fuel mixture to prevailing cylinder temperature, air pressure, and exterior temperature.
A PC can be used to monitor all engine data. The user interface is so intuitive that all of the engine’s settings and maintenance can be easily conducted. The CAN bus serves as communication. Actuation of the servo-motors and injection, the analysis, sensor signals (analogue and digital), general and manual diagnostic functions, and system updates can be controlled vial the CAN bus.

HKZ215, the new ignition system that Sky Power also developed at the same time, is likewise tuned to all of 3W-International’s engines. The new ignition can also be used for 2- and 4-stroke engines. Both systems are already being used today in the 3W-180 SRE hybrid Wankel engine from 3W-International introduced in 2017. The high-performance HKZ system was developed for significantly greater ignition powers. The engine’s overall fuel efficiency is thereby enhanced and the exhaust values improved. The HKZ is installed in a lightweight and rugged, nickel-plated aluminium housing. All the add-on components such as connector plugs and spark plug connectors are designed and shielded for challenging application areas.

“We are achieving better power performance in 3W engines with the new ignition and injection system”, Schudt explains. The test of a production engine from the 3W-110xi B2 TS FI series demonstrates this. The engine was tested with two different trial constructions having the same silencer L70 aluminium and the same 24×14 dual-blade propeller. In the first trial, the engine ran with the conventional ECU and ignition from 3W-International. These were exchanged for the ECU030 and HKZ215 in the second trial. In the process, a fuel reduction of up to 28% at 5500 rpm resulted. Even reductions of up to 69% could be demonstrated in the lower rotational-speed ranges. “The results aloft also surprised us, but they clearly show what is possible in the area of efficient fuel management”, according to Schudt.

In addition to the injection and ignition, the intake body was also optimized on the cylinders. The engine’s power density is greater thanks to the now better cylinder filling. The engine generates fewer harmful exhaust components and can be better controlled in different engine states. The improved combustion furthermore creates fewer residues in the engine, leading to a reduction in maintenance intervals. Moreover, the engine can be integrated into the aircraft independently of position, leading to optimum integration and weight distribution.

“The new ignition and injection system is obtainable for all of 3W-International’s gasoline and HF engines. We are also offering to convert drive systems already in use on the market. For this purpose, the engine has to be sent in to our service centre in Germany. Conversion effort is engine dependent”, explains Schudt. At the moment, the new systems are usable for the 110 ccm engine. Additional engines will follow in future. “The goal is to offer the ECU030 and HKZ ignition system for all of 3W-International’s 2-stroke engines”, according to Schudt.