FLY-LION3: A regional submarine cable connecting Mayotte and Comoros
The FLY-LION3 submarine cable is a 400-kilometer fiber optic system linking
Kaweni in Mayotte to
Moroni in the Comoros. Commissioned in 2019, according to GeoCables records, it is operated by a consortium comprising Comoros Cables, Orange, and Société Réunionnaise du Radiotéléphone. It serves as a critical link between these island territories in the Indian Ocean, facilitating regional connectivity and integration into global telecommunications networks.
What makes FLY-LION3 noteworthy is the limited public disclosure about its technical specifications, such as design capacity, fiber pair count, and supplier details. This lack of transparency is not uncommon for smaller regional systems but leaves room for speculation about its full capabilities. Additionally, live latency measurements from Moroni to Kaweni show significant deviation from theoretical calculations, raising questions about the broader network infrastructure and routing practices.
Quick facts
| Cable name | FLY-LION3 |
| Length | 400 km |
| Ready for service | 2019 (GeoCables database value) |
| Owners | Comoros Cables, Orange, Société Réunionnaise du Radiotéléphone |
| Status | In service |
| Design capacity | Not disclosed |
| Fiber pairs | Not disclosed |
| Supplier | Not disclosed |
| Landing points | Kaweni (Mayotte), Moroni (Comoros) |
| Other cables at Kaweni | Lower Indian Ocean Network 2 (LION2) |
| Other cables at Moroni | 2Africa, Avassa, Eastern Africa Submarine System (EASSy) |
| Computed one-way latency | ≈ 2.0 ms |
| Computed RTT floor | ≈ 3.9 ms |
| Measured RTT (Moroni -> Kaweni) | Min 67.9 ms, Avg 166.8 ms |
Route
FLY-LION3 connects Kaweni on the French overseas territory of Mayotte to Moroni, the capital of the Union of the Comoros. Both landing points are located in the western Indian Ocean, a region characterized by its reliance on submarine cables for international connectivity due to the geographic isolation of the islands. Kaweni is also a landing site for the LION2 cable, while Moroni hosts multiple other systems, including 2Africa, Avassa, and EASSy, making it a significant node in the regional telecommunications network.
Why it was built and what it carries
The primary purpose of FLY-LION3 is to enhance connectivity between Mayotte and Comoros, providing a direct link to support local telecommunications needs and integrate the islands into broader international networks. By connecting to Kaweni, which is linked to LION2, the cable indirectly facilitates access to global systems. It likely carries a mix of internet traffic, voice communications, and enterprise data, though specific traffic patterns are not publicly documented. Its role in complementing other cables landing at Moroni suggests it contributes to redundancy and increased bandwidth availability for the region.
History: what can be established
FLY-LION3 was recorded as ready for service in 2019 in the GeoCables database. No conflicting dates have been identified in publicly available industry sources, suggesting consensus on its commissioning year. The cable's construction aligns with broader efforts in the region to improve connectivity and reduce reliance on terrestrial or satellite links, which are often slower and more expensive.
Capacity and technology
Publicly available information does not disclose the design capacity, fiber pair count, or supplier details for FLY-LION3. Without operator documentation, it is impossible to state these specifications definitively. The cable's technology is also not detailed in public sources, leaving its transmission capabilities open to speculation. Given its relatively short length and regional focus, it likely employs standard industry practices for submarine cable systems, including optical amplification and modern fiber optic technology.
Latency: the physics
The computed one-way latency for light propagation over the 400-kilometer wet segment of FLY-LION3 is approximately 2.0 milliseconds, with a theoretical round-trip time (RTT) floor of 3.9 milliseconds. These calculations assume ideal conditions, including light traveling at 200,000 to 204,000 km/s in fiber. However, live measurements of RTT between Moroni and Kaweni show a minimum of 67.9 milliseconds and an average of 166.8 milliseconds over 65 checks. This discrepancy reflects the impact of land tails, terminal equipment, and routing inefficiencies, which add significant delays beyond the cable's wet segment.
Redundancy: what happens if it breaks
If FLY-LION3 experiences a fault, connectivity between Mayotte and Comoros would rely on alternative systems. Kaweni is connected to LION2, which could provide a backup route. Similarly, Moroni hosts multiple cables, including 2Africa, Avassa, and EASSy, offering diverse paths for rerouting traffic. Standard industry practices for submarine cable repair would involve deploying specialized cable ships to locate and fix the fault. Repairs can take weeks depending on the nature of the damage and weather conditions, but redundancy in the region mitigates the risk of prolonged outages.
Bottom line
- FLY-LION3 is a 400-kilometer submarine cable linking Mayotte and Comoros, commissioned in 2019.
- Owned by Comoros Cables, Orange, and Société Réunionnaise du Radiotéléphone.
- Technical specifications such as design capacity and fiber pairs are not publicly disclosed.
- Computed latency is ≈ 3.9 ms RTT for the wet segment, but live measurements show much higher values due to network factors.
- Redundancy is provided by other cables at Kaweni (LION2) and Moroni (2Africa, Avassa, EASSy).