From Leadership Profile: Vertiflite May/June 2014
Blanche Demaret, Delegate Director for Rotorcraft, ONERA
Within the French national aerospace research center ONERA (formerly the Office National d’Etudes et de Recherches Aérospatiales), Blanche Demaret oversees rotorcraft Research and Technology (R&T) investigations sponsored by government and industry. She explains, “ONERA has 17 departments. Thirteen of them are involved in rotorcraft programs. My job is to support the involved teams and to manage studies in that domain.” The rotorcraft effort has about 70 full-time scientists, engineers, and technicians in various departments. “I am based close to Paris, and the departments I work with are in Toulouse, Salon de Provence, and Lille. I have to travel a lot between the centers.” The investigations also stretch across Europe with the Clean Sky initiative pursuing more efficient rotary- and fixed-wing technology for environmental aspects. “ONERA is one of the main R&T players in this large project. We commonly work with a large set of partners – universities, research centers, and industry. We have both Airbus Helicopters and AgustaWestland as partners in this Clean Sky framework. Our main topics are shape optimization for performance improvement, drag reduction with active and passive controls, drag reduction shapes for parts of the helicopter, low noise, and reduction of environmental footprint.”
Blanche Demaret’s career has centered on rotorcraft science and technology. She offers, “The main problem with expanding the use of helicopters is public acceptance. Helicopters are reputedly noisy and dangerous. If you ask people what is their perception of helicopters, they say ‘too noisy.’ Helicopters also operate in dangerous conditions of bad visibility, so we need to improve safety by pilot assistance, by sensors and by providing the right information at the right time. We also have to reduce cost – this is a true limitation on the commercial use of those aircraft. For us on the research side, the way to reduce cost is by reducing weight or increasing performance; we are not dealing with manufacturing costs.”
Born and raised in Paris, Ms. Demaret grew up in a family without engineering influences. “For sure, they were very curious about my going into engineering. At that time, it was not so common, and my family didn’t have any engineers – military people but not engineers.” A two-year Classe Préparatoire typically prepares French students for engineering studies. However, in 1972 avenues for young women in the field were limited. “I entered an engineering school called EPF (then Ecole Polytechnique Feminine) which was created in 1925 to train women engineers. At that time, it was very unlikely that a woman could become an engineer. I knew from a friend who had been there at the beginning that the instructors were really top-level engineers.”
The EPF engineering curriculum had no helicopter content, but Blanche Demaret found aerospace studies interesting and challenging. “These were just aeronautical courses, all disciplines, but in general more fixed-wing. In fact, rotary-wing first came into my life when I joined the DGA [Direction Générale pour l'Armement] in 1977 because this was the task I was assigned.” The French armaments procurement agency then managed mid- and long-term aeronautical research. “DGA is part of the French Ministry of Defense, and I was very interested in working for my country. The first job I got was in the research department for the Directorate for Research and Techniques (DRET) in the field of helicopter applications. The group I was working with specialized in aerodynamics and flight mechanics.
“My task was to give orientation to the rotorcraft research to make progress, improve performance, and explore new concepts. I was working with industry, with research centers, and with academia for civil and military applications.” The DGA funded development of rotorcraft modeling tools. Ms. Demaret recalls, “The people from [then] Aerospatiale convinced me that there was a real need for a large numerical tool for flight mechanics simulation. In my position, I was the one able to give first contractual support to HOST – the Helicopter Overall Simulation Tool. The tool is now in day-to-day use at Eurocopter/Airbus Helicopter and shared with ONERA for further developments.”
DGA also supported ONERA on far-reaching rotorcraft technologies. “One of the great successes for us was a contract to ONERA and Airbus Helicopters [then Eurocopter] for exploring new blade shapes. “The contract for ERATO [Etude d’un Rotor Aéroacoustique Technologiquement Optimisé] was to reduce the noise of rotors. This became the BlueEdge blade. More than 30 years later, I’m still waiting to see this new blade design fly on a commercial helicopter. It has been tested in flight and announced by Eurocopter in 2010, and I am anticipating to see an ONERA product flying on new helicopters. ”
The DGA research directorate DRET was closed down by the French MoD in 1996. “The second part of my life in DGA was dedicated to cooperation and export support.” As deputy for international affairs for the aeronautical program directorate from 2001 to 2004, Ms. Demaret supported foreign customers and cooperative programs such as the NH90 and Tiger helicopters and A400M military transport. She was also on hand for the fusion of French and German rotorcraft research. “When Eurocopter was created in 1998, the French Aerospatiale and German MBB were used to work closely with their national research centers. ONERA and DLR, the German Aerospace Research Center, could compete for each study offered by Eurocopter, the bi-national industrial entity, or agreement to develop a common rotorcraft program. Since 2000, there has been only one research program integrating all the studies at ONERA and DLR, even if the studies are only involving one nation. All are managed together.”
Blanche Demaret left the DGA for research in 2004. “When Jean-Jacques Philippe, the director for rotorcraft research at ONERA, retired, he asked me in 2004 to be his successor. I was pleased to work again with the research teams I had known for a long time, like going back to the family circle.
We were working with noise, performance improvements, increasing flight safety. For this, we needed a better understanding of rotorcraft physics and better simulation tools.” The Franco-German SHANEL (Simulation of Helicopter Aerodynamic Noise and ELasticity) program led ONERA to apply computational fluid dynamics (CFD) software to helicopter blade-vortex interactions at the end in 2010. Ms. Demaret notes, “This project was launched in cooperation with Eurocopter and also in cooperation with DLR. It was very interesting comparing the codes because DLR was working on its own tools and we were working on ours . . . . It provided a lot of improvement in terms of numerical tools, calculation time, turbulence models, wake models, and so on. It also included structural mechanics modules. ONERA assigned a license to Airbus Helicopters for industrial use.”
ONERA has eight centers located around France. The Modane in the French Alps has one of the world’s largest supersonic wind tunnels. Helicopters and tilt rotors have been tested there. Ms. Demaret explains “We have tested, several times, isolated rotors because the speed of rotors in the true condition of flight can be subsonic but close to Mach 1 at the blade tip.” The pressurized wind tunnel near Toulouse has tested complete helicopter scale models with rotating blades. “This is used for flight mechanics identification. We also measured the blade-vortex interaction for rotor noise evaluation. In addition, ONERA shared the experimental data basis with partners and, for example, with the US Army.”
The French research center is working on advanced rotorcraft concepts. “This is one of the missions of ONERA, to think about what can be or what we imagine is possible to fly in 2050. In terms of helicopters, I think industry has some good ideas with the X3 and with tilt rotors.” Ms. Demaret says, “My opinion is that speed is an advantage in helicopters targeting shuttle or corporate flight. If you are looking for a military helicopter, for sure speed is an added feature. But if you’re looking for efficiency, safety, and payload for commercial flight, if you are looking to the European market, helicopter cost and noise issues have to be solved maybe before the speed. In other countries and other markets, speed is progress, but for us, the Direct Operating Costs and Direct Maintenance Costs should stay at the center.” ONERA looks to active materials as an enabling rotorcraft technology. Ms. Demaret explains, “These composite microfibers which are deformed by a pulsating electric current, or piezoelectric actuators, can be incorporated into the blades to modify their airfoil or twist according to the blade azimuth to improve their efficiency, and therefore the behavior and performance of the helicopter rotor.”
ONERA is cooperating with DLR and other European partners and with worldwide research centers. One of the longest cooperative activities continues with the US Army’s Aeroflightdynamics Directorate and Aviation Engineering Directorate in the field of helicopters. The cooperation was launched in 1971 and now includes Georgia Tech and NASA. “This is important and very fruitful cooperation for all the partners,” says Ms. Demaret. “Personally, I am very proud to have had the opportunity to be an active player on this team with the key members of the research and industry. My luck has been to make my passion my job.”
AHS International has also given ONERA’s rotorcraft director global contacts. “As an AHS member, I’ve had the opportunity to join a large and international network where all members are involved or interested in rotorcraft. This is a unique community for rotorcraft people.” Blanche Demaret is deputy technical chair for the 70th Annual AHS International Forum this May and will serve as the technical chair for Forum 71 in May 2015 in Virginia Beach VA. She is also a member of the International Committee for the European Rotorcraft Forum and is now beginning to prepare for the 2016 ERF in France.
Ms. Demaret explains, “As Director for Rotorcraft Research in our National Research Center, my main interest is to identify the trends, needs, and gaps in order to give a more relevant orientation to the research to be performed. The AHS specialists’ meetings and the AHS International Annual Forum are both the must-attend forums in order to meet all the players of the rotorcraft world: universities, industry, government officials, and operators.”