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Analysis Method for Non-Nominal First AcquisitionFirst this paper describes a method how the trajectory of the launcher can be modelled for the contingency analysis without having much information about the launch vehicle itself. From a dense sequence of state vectors a velocity profile is derived which is sufficiently accurate to enable the Flight Dynamics Team to integrate parts of the launcher trajectory on its own and to simulate contingency cases by modifying the velocity profile. Then the paper focuses on the thorough visibility analysis which has to follow the contingency case or burn performance simulations. In the ideal case it is possible to identify a ground station which is able to acquire the satellite independent from the burn performance. The correlations between the burn performance and the pointing at subsequent ground stations are derived with the aim of establishing simple guidelines which can be applied quickly and which significantly improve the chance of acquisition at subsequent ground stations. In the paper the method is applied to the Soyuz/Fregat launch with the MetOp satellite. Overall the paper shows that the launcher trajectory modelling with the simulation of contingency cases in connection with a ground station visibility analysis leads to a proper selection of ground stations and acquisition methods. In the MetOp case this ensured successful contact of all ground stations during the first hour after separation without having to rely on any early orbit determination result or state vector update.
Document ID
Document Type
Conference Paper
Sieg, Detlef
(EDS Operations Services G.m.b.H. Darmstadt, Germany)
Mugellesi-Dow, Roberta
(European Space Agency. European Space Operations Center Darmstadt, Germany)
Date Acquired
August 24, 2013
Publication Date
September 24, 2007
Publication Information
Publication: Proceedings of the 20th International Symposium on Space Flight Dynamics
Subject Category
Spacecraft Design, Testing And Performance
Distribution Limits
Public Use Permitted.
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