  Collision avoidance is a topic of growing importance for any satellite
orbiting Earth. Especially those satellites without thrusting capabilities face
the problem of not being able to perform impulsive collision avoidance
manoeuvres. For satellites in Low Earth Orbits, though, perturbing
accelerations due to aerodynamic drag may be used to influence their
trajectories, thus offering a possibility to avoid collisions without consuming
propellant. Here, this manoeuvring option is investigated for the satellite
Flying Laptop of the University of Stuttgart, which orbits the Earth at
approximately 600 km. In a first step, the satellite is aerodynamically
analysed making use of the tool ADBSat. By employing an analytic equation from
literature, in-track separation distances can then be derived following a
variation of the ballistic coefficient through a change in attitude. A further
examination of the achievable separation distances proves the feasibility of
aerodynamic collision avoidance manoeuvres for the Flying Laptop for moderate
and high solar and geomagnetic activity. The predicted separation distances are
further compared to flight data, where the principle effect of the manoeuvre on
the satellite trajectory becomes visible. The results suggest an applicability
of collision avoidance manoeuvres for all satellites in comparable and
especially in lower orbits than the Flying Laptop, which are able to vary their
ballistic coefficient.
