Explained: What is NOTAM & and why its failure led to grounding of thousands of US flights

NEW DELHI: Hundreds of flights were grounded in US early Wednesday after a major glitch in the system, leaving passengers across the country stranded at airports.
The US Federal Aviation Administration (FAA) said that flights were grounded due to failure of a key pilot notification system called Notice to Air Missions (note).

It said it is still working to fully restore the system.
In an earlier advisory on its website, the FAA said its NOTAM system had “failed”, although NOTAMs issued before the outage were still viewable.
What is NOTAM?
A NOTAM is a notice containing information essential to personnel concerned with flight operations, but not known far enough in advance to be publicized by other means, according to the FAA website.
* NOTAMs indicate the real-time and abnormal status of the NAS impacting every user.
* NOTAMs concern the establishment, condition, or change of any facility, service, procedure or hazard in the NAS.
* NOTAMs have a unique language using special contractions to make communication more efficient.
NOTAMs basically provide information about potential hazards or changes to flight operations that may affect safety.
This information can include things like temporary flight restrictions, changes to air traffic control procedures, runway closures, and other issues that could impact flights in a specific area.

When are NOTAMs used
NOTAMs are typically issued on a short-term basis, and they are meant to be used by pilots, air traffic controllers, and other aviation professionals to stay informed about changes to flight operations.
They are also used by airport operators and other organizations that need to be aware of potential hazards or disruptions to flights in order to plan accordingly.
When a NOTAM is issued, it is distributed to a variety of different sources, including flight planning software, flight information publications, and websites that specialize in aviation information. Pilots are typically required to check NOTAMs before taking off in order to ensure that they are aware of any hazards or changes that could impact their flight.
Overall, the NOTAM system is an important tool for ensuring the safety and efficiency of flight operations by providing pilots and other aviation professionals with critical information about potential hazards and changes to flight operations.
(With inputs from agencies)