European Researchers Develop Self-Healing Composite Material for Spacecraft

March 25, 2026

The Project Cassandra test panel for self-healing carbon fiber composite material for spacecraft. (Image: ESA)

Healable spacecraft structures could soon be possible thanks to cutting-edge composite technology. Swiss companies CompPair and CSEM , and Belgian company Com&Sens have partnered with the European Space Agency (ESA) to modify their self-healing carbon fiber product for use in space transportation.

Project Cassandra — an abbreviation for Composite Autonomous Sensing and Repair — includes sensors and a heating element within a composite carbon-fiber material, allowing spacecraft to autonomously repair initial stages of damage.

Cassandra is part of ESA’s Future Innovation Research in Space Transportation (FIRST!) Initiative which is finding and testing innovative technology that will benefit European space transportation.

Infrared images of Cassandra repair process on a test sample through heating. (Image: ESA)

Composite materials like carbon fiber reinforced polymers are increasingly being used in spacecraft structures. They are composed of a polymer matrix, reinforced with layers of carbon or glass fibers. This creates a strong and lightweight material, resistant to corrosion. However, composite materials are also sensitive to damage – especially if they were to fly to space and back repeatedly – and small cracks can worsen over time. Repairs can be expensive and time consuming and may weaken the structural integrity.

With this in mind, CompPair developed ‘HealTech’, a composite material that can “self-heal”. By heating the material, a healing agent inside activates and reflows to repair damage caused by impacts or stress.

“I’m excited by the autonomy and durability benefits we can bring for the future spacecrafts and launchers, closing the gap between science-fiction and reality,” said CompPair Chief Technology Officer Robin Trigueira. “This project is a major step for CompPair in the space sector, HealTech is unlocking unprecedented technological advancement for composite material health monitoring and management, clearly highlighting the possibilities brought by healable composites for reusable space structure costs efficiency.”

Cassandra demonstrator diagram. (Image: ESA)

A prototype of the composite structure was created by integrating a network of fiber-optic sensors into HealTech’s resin-imbued fibers. The sensors pinpoint any damage to the structure. Once spotted, the material is heated through integrated 3D-printed aluminum grids to 100 –140°C.

Various samples of the material ranging from 2x10 cm to 40x40 cm have undergone testing. The tests focused on the efficacy of the material’s damage monitoring, homogenous heating and self-repair abilities. Additionally, thermal shock tests were conducted to monitor the response of the material to the typical conditions of a cryogenic tank.

The next stage of testing will involve adapting the material to a larger shape such as a complete cryogenic fuel tank.

This material could reduce waste resulting from space missions, and would be ideal for reusable launchers. “Implementing this technology into our systems could have enormous benefits for space transportation,” said ESA’s Bernard Decotignie. “It will help develop reusable space infrastructure and reduce mission costs. This really proves what European innovation can do for the space sector.”

Source