Ariane 62 | Galileo L15 (FOC FM28 & FM31)

Ariane 62's Galileo L15 Mission: Bolstering Europe's Navigation Backbone

On December 31, 2026, the European Space Agency (ESA) is set to launch the Galileo L15 mission aboard the Ariane 62 rocket from the Guiana Space Centre in Kourou, French Guiana. This flight will deploy two Full Operational Capability (FOC) satellites, FM28 and FM31, into medium Earth orbit, further expanding Europe's Galileo global navigation satellite system (GNSS). As the constellation nears completion, this mission underscores the continent's push for sovereign positioning, navigation, and timing (PNT) capabilities, rivaling systems like GPS and BeiDou.

The primary objective of Galileo L15 is to enhance the Galileo constellation's accuracy, reliability, and coverage. Each FOC satellite weighs approximately 730 kilograms and operates at an altitude of about 23,222 kilometers. Equipped with advanced rubidium atomic clocks and hydrogen maser clocks—the most precise timepieces ever flown in space—these satellites provide positioning accuracy down to the meter for civilian users and centimeter-level precision for authenticated services. Beyond navigation, they support search-and-rescue operations via the Cospas-Sarsat system, detecting distress signals and relaying them to ground stations in under 10 minutes. The payload's capabilities also include encrypted signals for military and governmental use, ensuring resilience against jamming or spoofing. By integrating these satellites, Galileo aims to achieve full operational capability with 30 satellites, offering global coverage and independence from foreign systems, which is crucial for applications in aviation, maritime transport, and autonomous vehicles.

The Ariane 62 rocket, making its debut in this configuration for Galileo L15, represents a modular evolution of Europe's heavy-lift capabilities. Developed by ArianeGroup under ESA oversight, it features a core stage powered by the Vulcain 2.1 engine, delivering 135 tons of thrust using liquid hydrogen and oxygen. Augmented by two P120 solid rocket boosters—each providing 4,650 kN of thrust—the 62 variant is optimized for medium payloads, capable of lifting up to 10.3 tons to geostationary transfer orbit (GTO) or 21.6 tons to low Earth orbit (LEO). Standing 63 meters tall with a 5.4-meter diameter fairing, the rocket incorporates cost-saving innovations like 3D-printed components and reusable manufacturing techniques, reducing production time by 40% compared to its predecessor, Ari