European Space Agency


The purpose of this project is to develop a gossamer sail system that can be used for deorbiting satellites at end-of-life. The principle that the system will use to achieve deorbiting is aerodynamic drag from the larger surface area. The system is intended mainly for low Earth orbit (LEO) telecom satellites but can potentially also be used in higher orbits, making use of solar radiation pressure to perform end-of-life manoeuvres. The objectives for the project are:
  • Undertake a detailed analysis of the requirements and potential use cases of a deployable sail deorbiting system.
  • Compare the concept with current de-orbit strategies and technologies
  • Design, manufacture and test an engineering model gossamer sail deployment system


This project will address the growing concern of orbital debris. This is a challenging problem with no single solution. Maintaining a compact volume envelope and low mass for a large deployable structure such as the gossamer sail is also challenging, as is deployment testing under gravity conditions.


The proposed de-orbiting system has advantages above other alternatives. It does not require propellant or electrical power throughout the de-orbiting phase and it is generally less complex than systems based on chemical or electrical propulsion. The system will be designed for an optimal de-orbiting strategy and low parasitic mass. The technology readiness level of solar sail and deployable sails is also at a high enough level, making this concept more feasible than other experimental technologies.


The deorbiting system features a two-stage deployment process. The first deployment uses a telescopic mast to extend the sail deployment mechanism so that it will not interfere with other satellite appendages and protrusions. It consists of a series of box-like structures that will deploy telescopically from the main body using rails.

click for larger image

click for larger image

click for larger image

click for larger image

click for larger image

click for larger image

In the next deployment phase the sail itself deploys. The sail consists of 4 triangular sections supported by 4 booms. The booms are coiled around a centre hub and the sail is folded in a separate volume. 

click for larger image


The project consisted of distinct work packages that focussed on
  • Analysis of needs, use-cases and requirements
  • Concept design of the proposed deorbit device
  • Detailed design of the proposed deorbit device
  • Manufacture and testing of an EM model to validate the proposed concept against the requirements and prove reliable functioning of the device.

Current status

The project has now been concluded.

The project ended with the successful conclusion of the test campaign of the deployable gossamer sail. Functional deployment of the device yielded many unforeseen problems, design challenges and testing challenges. These were successfully mitigated and the team succeeded in consistently deploying a 5m x 5m sail. Environmental tests, vibration, thermal/vacuum testing and loading and survivability tests served to validate the engineering model against the design requirements. As a consequence, the project has taken the overall system technology readiness to level 5/6.



Status date

Thursday, December 19, 2013 - 11:18