Thousands Of US Flights Delayed Due To Technical Glitch. Know Why And How It Happened

Around 9,600 flights have been delayed so far and more than 1,300 canceled, stated FlightAware, in the first national grounding of flights in the US in about two decades.

The US aviation sector has been struggling to manage one of the worst crisis situations on Wednesday that caused a nationwide ground stop imposed by the Federal Aviation Administration (FAA) over a computer issue that forced a 90-minute halt to all US departing flights.

Around 9,600 flights have been delayed so far and more than 1,300 canceled, stated FlightAware, in the first national grounding of flights in about two decades, reported news agency Reuters. Several industry officials compared the grounding of flights to the incident after the terror attacks on September 11, 2001.

What is the impact on airline services?

The total number of flights affected touched 10,900 and the figure increased, but airline officials expressed confidence that normal operations could largely return by Thursday, the report added.

Major airlines such as Southwest Airlines Co, United Airlines, Delta Air Lines and American Airlines all reported 40 per cent or more of flights on Wednesday were delayed or canceled.

What exactly happened?

The flights across the US were canceled or delayed after a system that offers safety information to pilots failed. The services were disrupted after the Federal Aviation Administration (FAA) system that is meant to distribute notices to pilots on hazards failed at about 2 a.m. Eastern Time, reported news agency Reuters citing officials.

It is when airlines were asked to halt on all domestic departures until 9 am eastern time while it tested whether crews had managed to restore the system and bring it back online.

The White House informed that US President Joe Biden was briefed on the disruption by Secretary of Transportation Pete Buttigieg. "There is no evidence of a cyberattack at this point," White House Press Secretary Karine Jean-Pierre said in a tweet. The US. Department of Transportation is conducting an investigation, she said.

As per FAA's latest update, it said, “We are continuing a thorough review to determine the root cause of the Notice to Air Missions (NOTAM) system outage. Our preliminary work has traced the outage to a damaged database file. At this time, there is no evidence of a cyber attack."

What is a Notam?

The breakdown bought to the fore the dependency of American air travel on the computer system that generates alerts called NOTAMs — or Notice to Air Missions.

The system failure is part of a nearly century-old practice originally known as Notices to Airmen – originally designed based on a system for notices to mariners.

The system, later changed to be termed "Notices to Air Missions" in 2021, basically alert pilots to hazards, starting from snow, volcanic ash or birds near an airport. This also provides information on closed runways and temporary air restrictions.

Notably, the NOTAMs sent by the FAA comprise a global safety system managed through the United Nations' aviation agency. Pilots are also required to review the notices, either printed on paper or on an iPad before taking off. The information provided can run up to 200 pages for long-haul international flights.

NOTAMs are written in a kind of encoded shorthand that had been originally designed to make communication more efficient.

How has the system changed?

The UN Civil Aviation Organization (ICAO) has been working towards overhauling the system to make it smoother for airlines and pilots to filter the most important warnings and present them in clearer language.

In July 2017 an accident was averted after an Air Canada jet landed on the wrong runway at San Francisco’s airport and was nearly colliding with four other planes. The notice of the closure of one of the two runways at the airport had been flagged in the pre-flight NOTAM – on page eight of a 27-page briefing - and missed by the pilots.

Pilots complain about the incident, and the information overload the system encourages prompted the effort to change the way the system operates. “(NOTAMs) are just a bunch of garbage that nobody pays any attention to,” US National Transportation Safety Board Chairman Robert Sumwalt noted during a 2018 hearing on the Air Canada incident, which helped spur a global campaign for change.

FAA officials have been involved in efforts to modernize the system in recent years.