Parabolic flights

Parabolic flights are used to conduct short-term scientific and technological investigations in microgravity and reduced gravity, to test instrumentation prior to use in space, to validate operational and experimental procedures, and to train astronauts for a future space flight.

Such flights are conducted on specially-configured aircraft, and provide repetitively periods of up to 20 seconds of microgravity or weightlessness. During a flight campaign, which normally consists of three individual flights, around 30 parabolas are flown on each flight, i.e. around 90 parabolas in total. On each parabola, there is a period of increased gravity (1.8 to 2 g) which lasts for about 20 seconds immediately prior to and following the 20 second period of reduced gravity.

The A300 has now been certified for flying parabolas that provides, in addition to microgravity, reduced gravity levels of 0.16g for approximately 23 s and 0.38 g for approximately 30 s. These gravity levels correspond to Lunar and Martian gravity levels.

Parabolic flights are the only sub-orbital carrier to provide the opportunity to carry out medical and physiological experiments on human subjects under conditions of microgravity or reduced gravity, complementing studies conducted in space, and in simulated conditions on ground (e.g. immersion, bed-rest).

They also provide physicists with the opportunity of carrying out hands-on investigations on processes characterised by short time scales. Along with drop-tower experiments, these are often a preparatory step towards more elaborate experiments on longer duration carriers such as sounding rockets or the ISS. For a number of physical processes, reducing the scale of experiments allows to also reduce its characteristic time scale while still having a significant dependence on the gravity level. There are numerous examples where these preparatory experiments eventually contributed first valuable scientific results and prominent publications, on top of the experience and knowledge required to define the details of longer term experiments.


For investigators, the major advantages of parabolic flights are:

  • Short lead-time: Typically a few months between research proposal and flight;
  • Low cost: ESA covers the cost of the flight opportunity for those research proposals selected for flight;
  • Flexible research approach: Laboratory-type, hands-on instrumentation is most commonly used;
  • Direct intervention: Investigators onboard the aircraft can interact with their experiments between and even during parabola;
  • Experiment modification: The experiment set-up can be modified or adapted between flights, as normally the three flights of a campaign occur on consecutive days.


ESA began flying parabolic flight campaigns in 1984. From this time up to 1988, a total of six campaigns were carried out from the Ellington airfield in Houston (Texas), using a NASA KC-135 aircraft.

In 1988, the French space agency CNES made its Caravelle zero-g aircraft available to ESA, and between this time and 1995 fifteen ESA parabolic campaigns were conducted.

Once, in 1994, ESA also flew one campaign on a Russian Ilyushin IL-76 MDK.

In 1996 ESA performed its 23rd campaign out of Bordeaux using a NASA KC-135 aircraft, and since the 24th campaign using the newly available Airbus A300 Zero-G aircraft in September 1997, and it is this unique aircraft that has been used ever since. The Airbus A300 Zero-G is basically operated out of the Bordeaux-Mérignac airport by the company Novespace.

How to Participate

Flight Opportunities for Scientists, Students and Media

ESA parabolic flight campaigns for science and technology investigations are generally performed twice per year, in Spring and Autumn.

Scientists and investigators are invited by ESA to submit proposals for experiments to be conducted during parabolic flight campaigns for microgravity or reduced gravity investigations, through a Continuously Open Research Announcement

Experiment proposals to be conducted in microgravity can be submitted at any time.

For experiments to be conducted in reduced gravity environment at 0.16g and 0.38g please contact the ESA science coordinators mentioned below.

Scientists and investigators who are interested to make use of these experiment opportunities are kindly requested to get into contact with one of the two following lead science coordinators at ESA:

  • For Experiments in the Field of Life Sciences:
    Dr. Patrik Sundblad
    Head of Life Science Unit
    Directorate of Human Spaceflight and Operations
    European Space Agency
    P.O. Box 299
    NL-2200 AG Noordwijk (The Netherlands)
    Tel.: +31 (71) 565 5187
    Fax: +31 (71) 565 3661
    Secretary: +31 (71) 565 3517

  • For Experiments in the Field of Physical Sciences:
    Dr. Olivier Minster
    Head of Physical Science Unit
    Directorate of Human Spaceflight and Operations
    European Space Agency
    P.O. Box 299
    NL-2200 AG Noordwijk (The Netherlands)
    Tel.: +31 (71) 565 4764
    Fax: +31 (71) 565 3661
    Secretary: +31 (71) 565 3517

In the framework of ESA's educational activities, ESA is also organising regularly parabolic flight opportunities for students at master or Ph.D. level through the "Fly Your Thesis" programme. Interested students should contact:

Or have a look at:

Since several years, ESA has adopted the policy of flying on each campaign qualified external observers, usually journalists, to report to the public on the on-going microgravity and reduced gravity research coordinated, supported and financed by ESA. Requests to participate in an ESA parabolic flight campaign by representatives from the media (print, Internet, TV or radio) should be directed to:

  • Mrs Rosita Suenson
    Human Spaceflight Communication Programme Officer
    Communication Department
    European Space Agency
    P.O. Box 299
    NL-2200 AG Noordwijk (The Netherlands)
    Tel.: +31 (71) 565 3009
    Fax: +31 (71) 565 5728
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