REL folded into bankruptcy at the end of October 2024. Both REL and REI ceased operations and laid off the bulk of their staff.
In 2015, BAE Systems agreed to buy a 20% stake in the company for £20.6m as part of an agreement to help develop Reaction Engines’ Synergetic Air-Breathing Rocket Engine (SABRE) hypersonic engine designed to propel the Skylon orbiter.