Czech company LA composite in Clean Sky projects

Company LA composite s.r.o. has successfully participated in implementation of 4 projects supported by the Horizon 2020 Clean Sky 2 Joint Undertaking (JU) (which currently continues under the Horizon Europe programme as the Clean Aviation Joint Undertaking).

The JU supports development of clean aviation technologies, namely those capable of significantly reducing carbon dioxide, nitrogen oxides and noise emissions. In addition, the programme contributes to the development of a globally competitive aeronautics industry and to strengthening European supply chains. The JUs are a form of public-private partnership, with part of the budget contributed by the European Commission from the Horizon programmes and part by industry groupings in the sector.

All four projects involving LA composite were coordinated by the Polish partner, the Institute of Aviation in Warsaw (ILOT). The third partner in the consortia is the Czech Aerospace Research Centre (VZLÚ).

In the following text, two of the projects are briefly introduced. Additional details on the implementation and impact of both projects were shared by LA composite development manager Petr Průcha, Ph. D. in a short interview.

The first project is DREAM (Design and realization of equipped engine compartments including cowling for a fast compound rotorcraft) launched on 1 January 2017. The aim of the project was the design and manufacture of the upper fuselage of a hybrid high-speed demonstrator called RACER by Airbus Helicopters. The upper part of the fuselage structure is made of composite materials and includes, Fairings, Cowlings (MGB Cowlings, Engine Cowlings, Exhaust Cowlings) with internal structure, ECS Air Intakes and Engine Air Inlets. The project was completed in 2021.

The second was LATTE (Full fairing for main rotor head of the RACER Demonstrator) project which started on 1 September 2017. This focused on the development and manufacture of an aerodynamic fairing for the main rotor head of Airbus Helicopters' hybrid high-speed demonstrator called RACER. The project ended on 30 June 2023.

Both projects are now completed and their outputs are being put into practice. On 25 April 2024, the first flight of the RACER hybrid helicopter prototype took place.

The Clean Sky/Clean Aviation strategy is to reduce the environmental impact of air transport. How do the results of both projects contribute to this goal? What exactly was LA composite's role in the projects?

This question is quite complex, so I will answer in a couple of steps. I will start with the area of reducing environmental impacts. This helicopter concept offers fuel savings of up to 20 % compared to a conventional helicopter, and at a cruising speed of over 400 km/h, which conventional helicopters are not able to achieve (conventional helicopters, for example, have a cruising speed of about 250 km/h). This saving has been achieved by several approaches. First of all, it is a hybrid concept, which means that the RACER Demonstrator is capable of the same flight modes as a conventional helicopter, mainly vertical take-off and landing, hovering in place in flight, but at the same time it can fly at higher speeds, it uses the lift force (lift) generated on the wings as an airplane. This is because a conventional helicopter must generate all the lift force that keeps it in flight on the rotor blades. Because a hybrid helicopter generates part of its lift in forward flight on the wings, the load on the carrier rotor decreases and it has to generate less lift, which leads to fuel savings, reduced drag on the main rotor and, last but not least, reduced noise.

Another factor is the use of push propellers on the side, which both compensate for the torque from the main rotor, but also create thrust for the helicopter to fly forward or backward. For a conventional helicopter to fly forward or backward, the main rotor must tilt or the entire helicopter must tilt, which again increases the load and drag on the main rotor in a conventional helicopter. Another significant saving is the use of 2 engines from Safran Helicopter Engines as these engines allow one of the engines to be shut down in cruise mode. This is made possible by the use of the lift generated on the wings. The way it works is that some of the lift is generated on the wings, so the main rotor then has to generate that much less lift.  At a cruising speed of 400 km/h, the lift generated on the wings is so great that only one engine is needed to power the main rotor, so the second engine can be shut down. To reduce the aerodynamic drag of the helicopter, the aerodynamic cowling developed and manufactured in the LATTE project contributed to significant reduction of the aerodynamic drag of the rotating main rotor hub.

On the part of the research consortium, we have contributed by using the advantages of composite materials in design and manufacturing to achieve maximum weight savings of the parts while achieving the desired properties. This was achieved by applying multiple approaches. The most significant weight savings have been achieved in the design and manufacture of even very complex parts from one piece with minimum joints. Of course, the use of carbon fibre reinforced composite materials with epoxy resin system was an obvious choice, allowing significant weight savings compared to aluminum alloy construction. Last but not least, it should be mentioned that it was necessary to comply with very strict requirements for the accuracy of the shape of the parts and their bonding during assembly, to minimize drag. On the part of the ILOT and VZLU project partners, the use of numerical tools to optimize the design in terms of strength and stiffness was a matter of course in the design of the parts.

LA composite was involved in the project from the very beginning, including the design phase when we opposed the design solutions in terms of materials, manufacturing processes, technologies and fixture requirements from the manufacturing point of view. The aim was to take these factors into account in order to achieve the required parameters of the proposed design and quality requirements, while still meeting the schedule and budget. Subsequently, LA composite was responsible for the design and manufacture of all the jigs and tools, definition of the appropriate technologies and manufacturing processes and their parameters, and the manufacture of the actual parts including the assembly and bonding of the sub-assemblies with subsequent delivery to the final assembly of the RACER Demonstrator.

How do you expect the innovations implemented in the RACER Demonstrator to translate into its competitiveness against alternative solutions?

As already mentioned, this helicopter offers fuel savings of up to 20 % compared to conventional helicopters with the same take-off weight in use today, but offers a significantly higher cruising speed. Its huge competitive advantage, therefore, lies not only in the reduction in fuel consumption and the resulting reduction in environmental impact, but above all in its high cruising speed, which is almost twice that of the current competitors. At the same time, it still retains all the advantages of a helicopter, i.e. vertical take-off and landing, hovering in place in flight, the ability to fly backwards and more. These advantages are significant in all areas of helicopter use, whether in passenger or cargo transport or air rescue, etc. Of course, the interest of the military cannot be overlooked for similar reasons. On the other hand, it must be said that this is a flight demonstrator and Airbus plans to carry out an extensive set of tests, not only flight tests, in order to fully verify all the properties and performance of the RACER Demonstrator.

The focus of topics in a Joint Undertaking calls tends to be quite narrow and specific. Have you also considered participating in "classical" Horizon calls?

To be honest, we have not considered it, because we like this approach. The objectives of these projects are clearly defined and the parameters of the project results are very well measurable, so you see very specific results at the end. Moreover, aviation is the area where we are most established as a company, but for many of us aviation is also a hobby not just work.

Partnerships and Joint Undertakings are a somewhat separate chapter in Horizon and tend to be seen as "closed clubs" of long-term collaborators. What advice would you give to, for example, a small company that would like to participate in the Clean Aviation calls?

Of course, aviation is a very conservative industry and many large manufacturers in particular form a kind of closed club, which is not easy to penetrate. On the other hand, the programmes to support research and development require the involvement of small and medium-sized enterprises, preferably from different countries, so that this closed club is actually forced to take the smaller entities in if the project proposal is to have a chance of success. A total of 40 partners from 13 countries participated in the RACER Demonstrator project. I am not sure whether I am called upon to advise companies on how to get involved, because we have not taken any dedicated steps to participate in the Horizon and Clean Sky 2 programmes. The way it worked for us was that the partners who were preparing the project proposal found us by themselves.  When an entity prepares a project proposal, it looks for interested parties to join the consortium and the most desirable ones are small and medium-sized companies, preferably from the former Eastern bloc countries.

If I can recommend something on the basis of our experience, it is not to neglect the presentation of the company on the web and social networks or with the national contacts of European projects, for example the Technology Centre Prague. Information on what the company can do and what experience it has should be readily available from public sources so that it is as easy as possible for the entity preparing the project proposal to find a suitable partner according to this publicly available information. On the other hand, in order to participate in projects such as DREAM and LATTE, it is necessary to meet certain necessary criteria, for example, to hold a management system certificate according to AS 9100, to hold an EASA Part 21 production authorization. So participation is not for every company, which on the other hand is understandable in this industry.

How was the cooperation with project partners? Did you build on existing partnerships or was this the first collaboration?

It was an extension of cooperation In the case of VZLÚ, which had been going on for many years, either on a commercial basis or within other projects supported by public funds. As far as the partner and project coordinator from Poland is concerned, this was the first cooperation. However, it gradually grew and we ended up with 4 projects in Clean Sky 2.

As far as the cooperation with project partners is concerned, I cannot complain about it. I don't want to make it seem like an agitation, but I think it was a very beneficial experience for everyone involved, because the Clean Sky 2 project requires very close collaboration. Which on the one hand makes it necessary to overcome not only language barriers, but on the other hand you learn a lot.

A separate chapter was the cooperation with the helicopter manufacturer Airbus Helicopters. We have been cooperating with this company as a supplier for 20 years, but the solutions to these projects were exceptional. Until now, we have operated as a supplier who receives drawings, specifications and often fixtures and carries out production according to clearly specified requirements. While participating in Clean Sky 2 allowed us to be involved from the start in the development of a completely new helicopter that represents a significant innovation, while bringing our own ideas and capabilities to the project, including a significant share of the development activities, so that we acted as a true partner, not just a supplier.

Could you briefly describe the implementation of the projects? Were there any major changes or problematic situations that needed to be addressed? How was the communication with Clean Sky?

In technical terms, the progress of the projects was the same as in the case of other commercial development projects referred to as Build to Spec. it means to develop, manufacture and test the product according to customer specifications. The project was implemented including the standard milestones of Project Kickoff Meeting, Preliminary Design Review, Critical Design Review, Production Readiness Review, System Acceptance Review, and Delivery. These were technically more demanding projects as they involved complex development of a major part of the helicopter including materials and structural elements testing, including Bird Strike Testing.

From the administration point of view, I can say that everything was relatively easy and with a minimum of effort. There were no major changes to deal with, except for the extension of the project duration due to the COVID 19 pandemic. But it should be added that we were the project partner, not the coordinator. Coordinator had to carry significantly more administrative work. The situation was a bit more complicated in the case of insurance. At the beginning of the project, Airbus Helicopters required the project consortium to have liability insurance of 50 million EUR. However, Clean Sky and Airbus Helicopters were gradually able to accept that they would have to be satisfied with an enterprise liability insurance with a significantly lower sum insured. No insurance company in the Czech Republic wanted to take out an insurance policy for such a high amount, and certainly not in this case where it is a flying demonstrator.

As far as communication with Clean Sky 2 is concerned, it was primarily electronic, including formal documents such as contracts, cost reporting, etc. via a web portal. However, whenever we dealt with anything non-standard or had questions, it was no problem to communicate with a specific Clean Sky officer by phone or email. More important meetings were often attended by Clean Sky representatives, so there was also room for face-to-face exchanges.

Picture by Airbus Helicopters