Eutelsat’s OneWeb faces 48-hour outage from leap year bug

Eutelsat’s OneWeb faces 48-hour outage from leap year bug is profiled by BTW Media because public-source evidence links it to internet infrastructure, governance, operational dependencies, or market visibility.

• Eutelsat’s OneWeb satellite broadband network went offline for 48 hours due to a software issue related to the leap year on December 31, 2024.
• The outage impacted the satellite service for nearly two days, with 80% of the network restored by January 1 and full service by January 2.

What happened: Leap year bug disrupts Eutelsat’s OneWeb network

Eutelsat’s OneWeb satellite broadband network faced a 48-hour outage starting on December 31, 2024. The disruption was caused by a software bug in the ground segment, specifically related to the leap year in 2024. The issue occurred due to a failure in the manual calculation for the GPS-to-UTC offset, which did not account for the extra day in the leap year.

As a result, the satellite network went offline, affecting connectivity for its users. The problem was identified quickly, and by January 1, 80% of the network had been restored. Full service was resumed by January 2, 2025. Importantly, the satellite hardware itself remained operational in space, and the issue was confined to the ground systems responsible for managing the satellite network. This incident highlights the challenges of managing time-sensitive systems, especially in satellite communication and navigation.

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Why it is important

The outage of Eutelsat’s OneWeb service highlights the often-overlooked challenges in satellite communications, particularly with time-sensitive systems like GPS and satellite navigation. The leap year bug that caused the disruption underscores the importance of robust software testing, especially when dealing with global navigation and communication systems that require precise time synchronization.

The issue came at an inopportune time, coinciding with the 25th anniversary of the Y2K scare, when similar concerns about software errors were at their peak. While OneWeb’s satellite network, with over 630 satellites in low Earth orbit (LEO), competes with larger constellations like Starlink, this incident illustrates that even advanced systems can be vulnerable to seemingly small software oversights.

For Eutelsat, this mishap is especially embarrassing considering its leading role in the SpaceRISE consortium, which is set to launch the IRIS² satellite broadband project by 2030. A failure like this raises questions about the readiness and reliability of future satellite networks, which could impact their adoption and long-term success in providing global internet connectivity.