Optimization of flyby schemes in the framework of ADR mission in LEO

The paper focuses on the flyby issue involving large-size space debris (LSSD) objects in low Earth orbits. The data on overall sizes of the known upper-stages and last stages of launch-vehicles make it possible to emphasize five compact groups of such objects from the satellite catalogue in 600-2000 km altitude interval. Distinctive features of changes in mutual distribution of orbital planes of LSSD within a group are shown on the RAAN deviations' evolution portrait. In case of the first three groups (inclinations 71°, 74° and 81°), the lines describing the relative orientation of orbital planes are quasi-parallel. Such configuration allows easy identification of the flyby order within a group, and calculation of the mission duration and the required total ΔV. In case of the 4th and the 5th groups (inclinations 83° and 97-100°) the RAAN deviations' evolution portrait represents a conjunction of lines chaotically intersecting. The article compares two world-wide known schemes applicable to LSSD objects' de-orbiting. © 2017 Univelt Inc. All rights reserved.