# L3Harris router may have caused a nearly five-hour disruption in the US aviation system

- Published: 2026-11-15 18:49 UTC
- Section: Sky & Space › Aviation
- Tags: L3Harris router, FAA outage, US air traffic control, flight delays 13 November, copper to fiber-optic, connection requests, Sean Duffy, Arkansas and Texas facilities
- URL: https://realtech.media/news/rt-f7357e630ce84d94f95b9099_l3harris_router_may/

**Preliminary data point to a router installed by contractor L3Harris that sent excess connection requests to other routers; more than 20 thousand flights were delayed or cancelled.**

![L3Harris router may have caused a nearly five-hour disruption in the US aviation system](https://realtech.media/media/2026/11/5a16b6e5202b3bce.webp)
*zamin.uz*

A disruption lasting nearly five hours in the US aviation system, together with the delay or cancellation of more than 20 thousand flights, may have been caused by a router installed by state contractor L3Harris, zamin.uz reports, citing Reuters. [1] According to preliminary data, the new device sent an excessive number of connection requests to other routers and overloaded the communication system. [1] The incident took place on 13 November.

## What happened on 13 November

The US Federal Aviation Administration (FAA) had to temporarily halt flights across the country for safety reasons. [1] The problem was observed at 17 of the country's 22 air traffic control centers. [1]

US Transportation Secretary Sean Duffy said that L3Harris had been carrying out planned work to replace old copper communication lines with a fiber-optic system. [1] The problems may be linked to routers installed at facilities in the states of Arkansas and Texas. [1]

## Router behavior and the open question of cause

Duffy explained that the new routers sent more than 1,000 connection requests to other devices every 4–5 seconds. [1] As a result, data exchange involving aircraft and radars became unstable at FAA centers. [1]

It has not yet been established whether the failure was caused by a defect in the routers themselves or by an error made during their installation and maintenance. [1] Duffy said that the investigation into the causes is continuing together with company representatives. [1]

L3Harris said it takes the incident seriously and is assisting the FAA with the investigation. [1] The company has completed more than 70 percent of the planned work to move the old copper communication system to a fiber-optic network. [1]

The routers that were due to be replaced had been in use for about 25 years, and their update had been planned as early as 2006. [1] The FAA spends about 1 billion dollars a year to maintain outdated communication systems. [1]

## Sources

1. [zamin.uz](https://zamin.uz/dunyo/227246-aqsh-aviatsiya-tizimidagi-yirik-uzilish-sababi-malum-boldi.html)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-f7357e630ce84d94f95b9099_l3harris_router_may/