Generic MLI Flap for Spacecraft Interface Rings: Design and Test Cases Results



Journal Title

Journal ISSN

Volume Title


2024 International Conference on Environmnetal Systems


The interface ring is by design a thermally unprotected part of a spacecraft because it must mechanically interface with the Launch Vehicle Adapter (LVA). Possible insulating solutions by means of coatings are limited and constrained by e.g. mechanical and electrical requirements. MLI blankets used on spacecrafts serve the purpose of radiative insulation, providing a passive and reliable thermal control strategy. However, the need of not interfering with the clamp-band attachment mechanisms makes the use of MLI or SLI also difficult to protect the interface ring. Such ring, once spacecraft – launcher separation occurs, gets exposed to external environment. Depending on the attitude, it becomes a means of heat losses when in shadow or of heat gains when Sun illuminated. Because of its strong mechanical and thermal coupling with the main spacecraft structure, the interface ring is a critical element for thermal control sizing. Constraints on mission attitudes and/or oversize of heating power are possible direct consequences of an interface ring exposed to space. In addition, variable heat loads through the interface ring to the structure along the orbit may induce thermo-elastic distortions sometimes incompatible with pointing accuracy requirements of optical instruments. With the aim of insulating from space environment the exposed surface of interface rings a generic and modular MLI flap solution, adaptable, with minor design modifications, to various diameter interface rings, has been designed, developed, manufactured, and tested at Beyond Gravity Austria GmbH under ESA funding. This paper aims at presenting such design and the associated testing campaign. It presents at support of it some results extracted from thermal analysis test cases run with real satellite models where the model of the MLI flap has been introduced to show the sensitivity that such design solution has on the overall thermal control of the spacecraft.


Christian Ranzenberger-Stindl, Beyond Gravity Austria GmbH, Austria
Zoran Ignjatov, Beyond Gravity Austria GmbH, Austria
Giovanni Chirulli, European Space Agency (ESA), The Netherlands
ICES202: Satellite, Payload, and Instrument Thermal Control
The 53rd International Conference on Environmental Systems was held in Louisville, Kentucky, USA, on 21 July 2024 through 25 July 2024.


Spacecraft interface ring, MLI flap, Thermal control