Site: MBB Deutsche Aerospace (MBB)
Space Communications and Propulsion Div.
MBB GmbH
PO Box 801169
D-8000 Munich 80
Germany

Date Visited: June 24, 1992

Report Author: N. Helm

ATTENDEES

NASA/NSF:

C. Bostian
N. Helm
C. Mahle
E. Miller

HOSTS:

Dr. Heinz W. Hermann

Manager, Business Development, Satellite Communications

Herr Kunkel

Remote sensing payloads

Herr Bassner

Platform technology

Dr. Baetz

Payload technology

Herr Dodel

Communications satellite technology

Dr. Nathrath

Antenna test center

BACKGROUND

MBB is caught up in a series of organizational changes that have recently taken place in the German aerospace and defense community, where small, medium and even large companies are being merged into larger industrial groups. The Daimler-Benz Group has acquired the leading aerospace companies, including Messerschmitt-Bolkow-Blohm (MBB), Dornier, MTU, ERNO, and Telefunken Systemtechnik, and has merged them into a multi-billion dollar organization named Deutsche Aerospace (DASA). DASA has four major divisions: Aircraft, Defense Systems, Propulsion Systems and Space Systems. Within the Space Systems Division there are three strategic business units: Satellites and Utility Systems, Space Transportation and Propulsion Systems, and Orbital Infrastructure. The primary purposes of these large industrial groups are to minimize competition and redundancy and to focus the entire group toward specific market requirements.

The Space Systems Division manufactures satellites for communications, remote sensing and scientific missions. Its major development programs include Ariane 4 and 5 launchers, the space glider HERMES, the COLUMBUS space station, a EUREKA space package to be launched and retrieved by the STS shuttle, and Sanger, the reusable dual-stage aerospace plane.

MBB has developed its "spacebus family" of systems and products, including sensors, thrusters, fuel tanks, attitude control and on-board control equipment. The antenna part of the "family" includes main and sub-reflectors, multifeed systems and tracking systems. One major development focus is ion propulsion. Minor members of the "family" include solar array drives, batteries, electronic power control equipment, and thermal control equipment. Ground equipment for TV, data and telecommunications networks, along with mobile earth terminal equipment, complete the minor category. Most of this work is being performed at MBB's headquarters, located in Ottobrunn, a southeast suburb of Munich.

RESEARCH AND DEVELOPMENT ACTIVITIES

Remote Sensing

MBB presented development efforts on imagers, radiometers, and spectrometers. Much of this work came out of research activity on a Modular Optoelectronic Multispectral Scanner (MOMS) successfully tested on-board the STS-7 in 1983 and again on STS-11 in 1984. Other efforts include the Infrared Background Signature Survey which has an IR radiometer and a spectrometer to be flown on a STS mission. The high performance demanded of the infrared sensor requires it to be carried in a super-critical helium vessel, i.e., cooled to very low temperatures. An IR sensor, also cooled with liquid helium, was recently flown on a SDIO mission with excellent results reported from the test data.

Platform Technologies

MBB is developing impressive platform or "bus" technologies to be used to support future mission payloads. Development areas include guidance and control systems, especially electric propulsion technologies, and power systems, especially solar generators.

MBB-ERNO is the overall manager of ESA's EUREKA program, and provided the orbital transfer assembly and the attitude and orbit control system for the retrievable space package or platform that was launched on the STS. Orbital thrust to move the platform from STS orbit to a 525 km orbit will be assisted by a RF Ion Thruster Assembly (RITA). The RITA thruster (along with a British Aerospace electron bombardment ion thruster) was also to be flight tested on the ESA ARTEMIS spacecraft. The two thrusters are expected to provide ten years of north/south station keeping, thus reducing the liquid fuel requirements for ARTEMIS by some 165 kgs. The state-of-the-art RITA thruster uses xenon as fuel. With 1.5 kV acceleration voltage, it produces a 48 km/sec exhaust velocity, a thrust approaching 15 mN and an ISP of 3000 s at a power consumption of 500 - 600 W.

In the solar generator or array area, MBB has produced many arrays flown on European satellites, as well as INTELSAT V, Brazilsat, ITALSAT and two Turksat satellites for which MBB has the order. MBB procures solar cells from different vendors to match the mission requirements, and then integrates the cells into a harness with modern materials, such as Kapton or Kevlar hybrid sandwich substrate insulation sheets. Good engineering was noted in the MBB solar array deployment mechanisms. An ongoing development effort to produce a low mass solar array should result in a 30-40% mass savings compared to conventional array technologies.

Payload Technologies

MBB is developing payload technologies for communications, Earth observation and scientific missions. One particular payload development discussed was a satellite communications "power amplifier for highly efficient and highly linear applications -PAMELA." This power amplifier uses a state-of-the-art technique to change the effective load impedance presented to the amplifying transistors dynamically with the drive level. If lower drive is accompanied by a higher impedance, efficiency is improved. Currently, this effort has produced an L-band amplifier with 47 dB gain, more than 40 W of output power, at an efficiency exceeding 40%. PAMELA amplifier technologies can be applied to higher frequency satellite systems. MBB plans to breadboard and test an amplifier for Ku-band satellites, where it sees a potential market.

Antenna Range Facility

In addition to advanced platform and payload technologies, many of the test and fabrication areas viewed during our site visit were state-of-the-art. In particular, the compact antenna range can be used from 2 to 220 GHz. The surface accuracy associated with large (6 m) antennas is 10 microns. These test facilities provide MBB with the ability to furnish high quality spacecraft antennas for potential customers. MBB also supplies such compact ranges to other aerospace companies.

A noteworthy fabrication technique was demonstrated during our visit to the antenna test facilities. This involves the creation of a light weight dichroic (frequency selective) reflector surface. A light weight substrate (in this case Kevlar) is coated with a conductive material. A precision laser then burns off the material in prescribed stripes, leaving a surface that appears highly reflective to one linear polarization and almost transparent to the orthogonal linear polarization.

SUMMARY

MBB Deutsche Aerospace is a competent integrator of spacecraft systems and a high quality manufacturer of space-qualified components.

MBB's transition from the largest aerospace company in Germany to now being only a part of a larger space and defense group is causing some difficulty, especially with its self-image, and likely loss of its name. The transition also comes at a time when the German government is proposing to reduce MBB's participation in ESA and to slow development on large space programs. However, the merger and acquisition movement in Europe is growing in most areas of space, defense and electronics. Large European companies such as MBB have decades of experience in program planning and development in which multi-national cooperation is essential to success. This experience has resulted in specialization that is less competitive and often more efficient. An example of this is a recent announcement that MBB has recently joined with Alenia Spazio of Italy to create a joint group to manage the COLUMBUS program.


Published: July 1993; WTEC Hyper-Librarian