A Tether-Stabilised Drag Kit for Retired Satellites: Area, Ballistic Coefficient and Decay Budgets

This study sizes the system named in its title from stated physical relations and a stated operating basis, and reports the result as SIMULATED, NOT MEASURED. The operating principle is deployable drag surface stabilised by a gravity-gradient tether, using atmospheric drag only. The drag kit is a civilian disposal accessory intended solely to shorten the orbital lifetime of its own host satellite after retirement; it carries no payload other than its own deployment mechanism. Every performance figure is computed by the deposited script from its inputs rather than asserted, and the headline outcomes include natural decay time for the bare host from the stated altitude of 52.8 years; decay time with the kit deployed of 4.15 years; ratio of natural to kit-assisted decay time of 12.7; ballistic coefficient with the kit deployed of 3.41 kilograms per square metre. Mass, power, time and energy budgets are assembled from components so they can be audited line by line, off-design behaviour is discussed openly, and the limits of the sizing are stated in full. The design is presented as a civilian system throughout, with its governing constraint identified and quantified rather than merely encountered.