On 23 May, the "Zero-g" Airbus A-300 will take off from Bordeaux-Mérignac airport in France on the first of a four-day campaign of parabolic flights designed to carry out experiments in weightlessness and test instruments and equipment before they are used in real spaceflight.
During the 28th parabolic flight campaign organised by the European Space Agency (ESA), experiments to be conducted on board sounding rockets and, later, on board the International Space Station, will be prepared. This campaign will focus on physical sciences and biology. Twelve experiments proposed by international teams of investigators, and the testing of crew support apparatus, will be performed between 23 and 26 May on the specially adapted Airbus A-300 "Zero-g".
Parabolic flights are practically the only means on Earth of reproducing weightlessness with human operators on board. During a parabolic flight, the "Zero-g" Airbus pilot - flying at an altitude of approximately 6000 metres, usually in a specially reserved air-corridor above the Gulf of Gascogne - first performs a nose-up manoeuvre to put the aircraft into a steep climb (7600m). This generates an acceleration of 1.8 g (1.8 times the acceleration of gravity on the ground) for about 20 seconds. Then the pilot reduces engine thrust to almost zero, injecting the aircraft into a parabola. The plane continues to climb until it reaches the apex of the parabola (8500 m), then it starts descending. This condition lasts for about 20 seconds, during which the passengers in the cabin float in the weightlessness resulting from the free fall of the aircraft. When the angle below the horizontal reaches 45°, the pilot accelerates again and pulls up the aircraft to return to steady horizontal flight. These manoeuvres are repeated 30 times per flight.
The 27 previous campaigns that ESA has conducted since 1984 have produced a total of more than 2.650 parabolas and almost 15 hours of weightlessness, the equivalent of flying around the Earth (in low Earth orbit) nearly 10 times. A total of 360 experiments have been carried out so far.
Some of the experiments being tested during this parabolic flight campaign will later be flown on sounding rockets. Using sounding rockets from its test range in Kiruna, Sweden, ESA has been running flight campaigns with Texus since 1977 (6 min. of absence of gravity), with Maser since 1987 (6 min.) and with Maxus since 1991 (12.5 min.).
With Europe and its international partners now building the International Space Station, where research will be carried out for the next 15 years, parabolic flights are also crucial to the preparation of experiments, equipment and astronauts and allow scientists to have their experiments tested before they are actually flown on a space mission.
Over the next four years, ESA will be running two parabolic campaigns a year. Scientists are regularly invited to submit experiment proposals for review and selection by peers. Those whose experiments are selected are given the opportunity to participate in an ESA parabolic flight campaign. A list of the experiments and scientists involved in the 28th campaign is attached. The subsequent ESA parabolic flight campaign (the 29th) is scheduled for November 2000 and will feature a mix of experiments in life and physical sciences, mainly focusing on physiological and medical experiments.
Further information on ESA parabolic flights can be found on ESA's special parabolic flight internet pages at :
http://www.estec.esa.int/spaceflight/parabolic
For further information:
Vladimir Pletser
ESA/ESTEC, Microgravity Payloads Division
Directorate of Manned Spaceflight and Microgravity
Tel: + 31.71.565.33.16
Fax: +31.71.565. 31.41
Anna Brück
ESA/ESTEC
Coordination Office
Directorate of Manned Spaceflight and Microgravity
Tel: +31.71.565.5445
Fax : +31.71.565.5441
For further information on ESA, visit our web site:
http://www.esa.int
Experiments and scientists involved in the 28th ESA parabolic flight campaign.
1."Hydrodynamics of wet foams" by Dr B. Kronberg (Institute for Surface Chemistry, Stockholm, S) and Dr M. Adler (University of Marne la Vallée, Paris, F). Will study different types of foams and will test a new method of forming foams by injecting C02 in different liquids. The technique of foam generation cannot be tested on the ground as foams are transient and collapse rapidly in 1g conditions.2."Interfacial turbulence in evaporating liquids" by Prof. J.C. Legros and Dr P. Colinet (University of Brussels, B). Will study the three-dimensional temperature field in an evaporating liquid (ethanol) caused by turbulent motions at the liquid-gas interface, known as Marangoni convection (after the name of an Italian scientist who studied interfacial phenomena between gas and liquids at the end of the 19th century).Technical aspects of these two experiments are being attended to by the Swedish Space Corporation, which is in charge of the preparation of the Maxus and Maser sounding rocket flights.3."Vibrational phenomena in inhomogeneous media" by Dr P. Evesque (CNRS, Ecole Centrale, Paris, F), Dr D. Beysens (CEA, Grenoble, F) and Dr Y. Garrabos (CNRS, Pessac, F). Will investigate the effect of vibrations in weightlessness on inhomogeneities in two-phase fluids and granular matter. This is one of the experiments recommended to fly in the Fluid Science Laboratory currently being developed for ESA's Columbus Laboratory.4."Liquid diffusion model experiments with the shear cell technique" by Prof. G. Frohberg, Dr A. Griesche (Berlin Technical University, D) and Dr G. Matthiak (DLR, Köln, D). Continues a previous experiment flown on the Russian satellite Foton-12. Diffusion is the main process in metallurgy and crystal growth. The diffusion coefficient of liquids is difficult to measure on the ground due to other mass transport phenomena resulting from gravity-induced natural convection.5."Study of synthesis of carbon species in microgravity" proposed by Prof. J.P. Issi, Dr J.C. Charlier and Dr J.M. Beuken (University of Louvain, B). Will investigate the synthesis of new forms of carbon, such as fullerenes, nanotubes and diamonds, by applying a strong electric discharge between two graphite electrodes. Similar experiments were conducted previously during parabolic flights and showed that the process of obtaining these different carbon forms could be improved to some extent.6."Recrystallisation of tungsten filament" by Dr R. Van Wijk and P. Dona (Philips Eindhoven, NL). Will study aspects of processing tungsten filaments to improve the performance of new lamps. This is one of the first experiments conducted directly by an industrial company in weightlessness, and shows the potential of applied research and development in microgravity.7."Laminar diffusion flames representative of fires in microgravity environments" by Prof. P. Joulain (CNRS, Poitiers, F) and Dr J.L. Torero (University of Maryland, USA). Continues a series of combustion experiments conducted during previous parabolic flight campaigns, sounding rocket flights and drop towers. The final experiment goal is to provide the scientific background necessary for the evaluation of material flammability in microgravity, enabling the risk of fire on board manned space vehicles to be reduced.8."Real-time physiological and molecular biological measurements of osteoblast-like cells under microgravity using fluorescence techniques" by Prof. D. Jones (University of Marburg, D) and Prof. Vander Sloten (University of Leuven, B). Will investigate bone cells stimulated mechanically in microgravity. Osteoblasts are responsible for the regeneration of bone tissues while osteoclasts are responsible for resorption of used bone tissues. The results will help to shed light on the mechanisms of bone resorption and regeneration, which are not yet fully understood.9."Effects of gravity at biomolecular level" by Prof. P. Vanni (University of Florence, I). Will investigate whether microgravity can affect enzyme reactions, complementing a previous experiment on a sounding rocket in 1996.10."Lipoxygenase activity in microgravity" by Dr M. Maccarone and Prof. A. Finazzi-Agro (University of Rome, I) with the support of Profs G.A. Veldink and J.F.G. Vliegenhart (University of Utrecht, NL). Will investigate the role of microgravity in enzyme catalysis reactions, as enzymes play important regulatory roles in all living cells, in both plants and animals.These two experiments (9 and 10) will use the EMEC (Effect of Microgravity on Enzyme Catalysis) module already flown on the Maser 7 sounding rocket in 1996, specially refurbished for this parabolic flight campaign by the firm Officine Galileo (I).11."Postural control in flatfish" by Prof. A. Berthoz (CNRS, Collège de France, Paris, F). Will study the behaviour of flat fishes swimming in a large pressurised aquarium. This experiment is related to the study of the inner ear vestibular system and complements previous investigations to bring more information on the central mechanisms of imbalance compensation, postural balance and asymmetries in the gravistatic system, thought to be the cause of space sickness. This is an experiment proposed by CNES that will fly in an ESA campaign in the framework of an experiment exchange agreement.12. "Testing of the Mirsupio crew support pouch" by engineers of ESA's European Astronaut Centre. Mirsupio is an improved multi-function wearable equipment pouch worn around the waist to support the astronaut in his daily life in orbit. An initial version of this pouch was flown on the Mir Space Station during the Perseus mission with ESA astronaut J.P. Haigneré.
