---

Home | Update | Latest Issue | Gallery | FR Profile | Datafiles | HELICOPTER 98

---

TECHNOLOGY FOR THE "HELICOPTER 2010"

While new helicopter models like the EC 120, EC 135, Explorer or Bell 407, become established in the market, scientists and engineers are already busy working on promising technologies for the next generation of rotorcraft.

According to Michael Stephan, manager of advanced development at Eurocopter Deutschland, an extensive research and technology program today is "vital for the survival of every company". Furthermore, it is essential to use their own and government funds as efficiently as possible. "We also have to include the suppliers, the research establishments, and the universities to be able to create an entire network", says Dr. Siegfried Sobotta, co-president of Eurocopter. He demands: "Research funding must be coordinated at the European level."

The goal of the efforts is clear: to increase the competitiveness of the industry. In other words, research should not become an end in itself, but, it must be the basis for products that can successfully compete in the world market. With this in mind, the focus of research is a direct result of the demands of the civil and military customers, along with the increasing requirements of the certification authorities. Also, it is extremely important to improve the public acceptance of helicopter. Last but not least, considerations concerning the development strategies of the competitors are also playing a role.

Putting these factors together, Eurocopter, in cooperation with German and French research establishments (DLR and ONERA), has derived four areas which should be handled with priority.

* Cost reductions are at the top of the list. All relevant market studies have indicated that the decisions of the customers today are largely influenced by procurement and operating costs. Even on the military side, lifetime cost considerations play an increasingly important role.

Due to this the manufacturers must aim for lower maintenance needs when developing new products, and also extend the lifetime of individual components. The goal is to reduce the production costs, among other means by an optimized utilization of different materials and by standardizing parts. Furthermore, there is potential for considerable savings in the development process as well. By improving and bundling computer programs for the generation of a "virtual helicopter", the development time could possibly be reduced to three years.

* Along with the costs, the mission capability of the helicopter plays a central role for the customer. In this area, particularly Europe is facing increasing limitations due to expanding safety requirements and because of the growing sensitivity of the public to any kind of aircraft noise. That's why Eurocopter is aiming for a reduction of the outside noise level to 10 EPNdB below the ICAO certification requirements. New profiles and rotor blade tip geometries are supposed to help, as are variable rotor rpms. Much hope is put on the continuous pitch control of each individual blade, for example through intelligent tabs actuated by piezoelectric motors.

Further work has the goal of achieving full all-weather capability to be able to expand the helicopter's mission capabilities. This requires improved navigation systems based on the ubiquitous GPS, along with radar or infrared sensors for terrain and obstacle avoidance in conjunction with a three-dimensional cockpit presentation, for example on wide-screen displays. Also, the de-icing of the helicopter must be assured.

* One area in which the helicopter is still lagging the fixed-wing aircraft is passenger comfort. The problems are known: vibrations are transmitted from the transmission (most often located overhead the passengers) into the cabin. Rotor, engine and transmission are generating a tremendous cabin noise, and also the air-conditioning for the cabin can be improved.

A remedy is possibly coming from active vibration isolation systems, better isolating cabin paneling, as well as, from efficient but light air-conditioning units. The challenge is to achieve a higher degree of comfort without significantly increasing either the weight or the costs.

* While the above mentioned goals mainly apply to civil helicopters, the military customers additionally require an increased survivability over the battlefield. This goal is supposed to be achieved by reduced detectability in the radar and infrared spectrum, along with improved electronic self-defence systems and optimized crash characteristics.

This short overview shows that there is a lot of work ahead for the helicopter manufacturers - and, progress is not available for free. Germany, for example, is providing DM60 million in the frame of its aerospace research and technology program, running from 1995 to 1998. This is complemented by an equal amount from the industry itself. Some of the interesting research projects supported by this programme are described in more detail on this pages.

Of course, many of the projected programs will last beyond the year 1998. Another five to ten years will go by before the results of the research programs will find their way into a production model. Continued support is thus very important.

Such a support could come from a second aerospace research program, something that is being considered by the Government at the moment. According to reports from the German ministry of economics, minister Günther Rexrodt is willing to support a second edition of the program at the current volume (share of 20 percent). The research ministry (BMBF) is a little more cautious, saying that much depends on the further development of Airbus financial requirements.

Should a new tranche of money become available, safety improvements and noise reductions will be the priorities in order to bolster the public acceptance of helicopters. Also, tilt-rotor developments (maybe under the Eurofar banner) should be considered, says Dr. Herbert Diehl from the BMBF. In this apparently prmising area, Bell and Boeing are currently holding a monopoly with their military V-22 and the civil 609 project.