The History of Sounding Rockets and Their Contribution to ... - ESA

6. Sounding-Rocket Programmes Devoted to Research under
Microgravity Conditions
The use of sounding rockets for research in the fi elds of materials and fl uid science, life sciences and fundamental
physics has already been briefl y addressed in Chapters 3.2, 4.3.5, 4.3.7 and 4.3.10. Over the last
30 years, the use of sounding rockets for research under microgravity conditions has developed into a major
and essential component of the overall European sounding-rocket activities. All of these microgravity-related
fl ights are carried out from Esrange, and some further details will be given in this chapter.
SPAR programme
The very fi rst time that sounding rockets were used for microgravity experiments was in the mid-1970s,
when NASA started its Space Processing Applications Rocket (SPAR) programme. SPAR used Black Brant
Vc rockets, which were spin-stabilised about their longitudinal axis using spin-up motors and slanted external
fi ns. After de-spinning and motor separation, the coasting phase starts. At altitudes above 100 km, where
the aerodynamic forces are suffi ciently low, residual accelerations of less than 1/10000 g are reached for 4
minutes and 20 seconds. During re-entry into the atmosphere, the drag forces gradually increase and ‘freefall’
conditions no longer prevail at altitudes below 100 km. Parachutes are deployed at altitudes of about 5
km to return the payload without major mechanical damage. These SPAR fl ight opportunities were used by
a few European scientists on a cooperative basis with NASA.
Texus programme
In 1976, Germany’s national Texus sounding-rocket programme was started and it continues to this day.
Texus (Technologische Experimente unter Schwerelosigkeit) used British Skylark 7 rockets, which provided
about 6 minutes of microgravity. Only recently, in 2005, the Skylark ceased to be commercially available,
so that from Texus 42 onwards (November 2005) the Skylark 7 has been replaced by the Brazilian VSB-30
rocket.
In 1982, ESA started to use Texus as a short-duration fl ight opportunity for Spacelab precursor experiments
by selected European researchers in the materials and fl uid sciences fi elds, and later also for biology experiments
in microgravity. The Texus experiments soon proved that sounding rockets are a powerful tool and
a cost-effective means for preparing and developing the operationally more complex and more expensive
experiments performed in orbiting laboratories.
The two-stage solid-propellant Skylark 7 rockets carried a scientifi c payload consisting of 250 kg of experiment
hardware, made up of three to four autonomous experiment modules, each with its own power supply
and data-handling system. The Texus payload concept provides a high degree of fl exibility, as well as easy
testing and maintenance/refurbishment of modules for re-use at moderate cost.
Maser programme
Since 1987, the Swedish National Space Board has offered to fl y ESA microgravity experiments under the
Swedish Maser (Materials Science Experiment Rocket) programme, managed by the Swedish Space Corporation
(SSC). Maser has practically the same technical capabilities as Texus, but instead of the Skylark 7
it used a Canadian Black Brant rocket, until Maser 5 in April 1992. From Maser 6 onwards, this programme
also used Skylark 7 rocket motors, and with Maser 10 on 2 May 2005 it launched the last existing Skylark
7. Maser 11 in 2008 will be launched by the Brazilian VSB-30.
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