USA. Failure of the NOTAM system, thousands of delayed and canceled flights

It’s about a defect in the system for notifying pilots about air missions – NOTAM. These are messages containing important information for airlines. They may concern e.g. runway closures, general bird hazard warnings, and low-level construction obstructions. The information can be up to 200 pages for long-haul international flights.

According to FlightAware, more than 10,000 flights have been delayed and over 1,300 canceled so far. It was the first domestic flight grounding in about two decades. Many in the industry compared the grounding to what happened after the September 11, 2001 terrorist attacks.

Major carriers such as Southwest Airlines Co, United Airlines, Delta Air Lines and American Airlines reported that 40 percent of or more flights have been delayed or cancelled. Airline officials said they believed normal operations could largely resume on Thursday.

FAA officials said initial analysis traced the issue to a corrupted database file. They added that there is no evidence of a cyberattack and that the investigation is continuing. The same file damaged both the main system and its backup, people familiar with the matter told Reuters, requesting anonymity.

FAA officials said they were working to “further determine the root cause” so that the problem could be avoided in the future.

Transport Secretary Pete Buttigieg told CNN that stopping departures was the “right decision” and it was necessary to ensure that messages were being sent correctly and there was no direct evidence of a cyberattack.

Buttigieg indicated that the backup system went into effect on Tuesday, but questions were raised about system performance, leading to a complete reboot of the system and prompting the FAA to issue a ground stop on Wednesday around 7:30 a.m. EST, and it was lifted after about 90 minutes – described Reuters.

An FAA adviser said the NOTAM system failed around 3:30 p.m. EST on Tuesday, meaning no new messages could be processed, Reuters reported.

“The outage could also affect air traffic on Friday,” said Captain Chris Torres, vice president of the Allied Pilots Association.

– Grounding lifted at 9am EST. That doesn’t mean the problem ends at 9am. The consequences will be long-term, said Torres, whose members fly for American Airlines.

One problem airlines face is trying to get planes in and out through crowded gates, which causes further delays. Crew time limit rules can also be a factor.