I run GPSJAM.org, have been studying and tracking the effects of GPS interference on aviation for the past 5 years, and I was a source for this article. I'm not a pilot and I don't work for any aviation agency.

I'm very curious to see what the final NTSB report says, but their preliminary report along with commentary from other analysts seems to show that this was a crew that made bad choices and died because of it. It also seems to show that GPS interference was a contributing factor to the accident, and that they'd likely be alive if the U.S. military hadn't been jamming GPS.

I think pilots need to be prepared to fly without GNSS, and also it might be a bad idea for the military to regularly deny GPS to thousands of civilian aircraft with tens or hundreds of thousands of passengers.

Lack of GPS isn't a critical safety issue, but it is a safety issue. GPS interference removes options, hurts situational awareness, disables or degrades other safety equipment (like TAWS, the Terrain Awareness and Warning System that is specifically designed to warn pilots that they're about to hit a mountain), and adds to crew and ATC workload and distraction.

Saying that this situation is what pilots train for and they should have just used VORs and ILS reveals an overly macho, unsophisticated understanding of aviation safety. We've added GPS, ADS-B, TCAS, GPWS, TAWS, etc. because they make flight safer. The airline industry and governments are concerned about GPS interference because of the aviation safety issues--if you're not concerned, you're thinking about the problem in a very narrow way ("I would never have trouble if my GPS died.").

In fact they think it's an urgent problem.

2024: "Aviation sector seeks urgent solutions for GPS interference" https://www.reuters.com/business/aerospace-defense/aviation-...

From a 2023 presentation by Eurocontrol at the UN International Committee on GNSS/Interference Detection and Mitigation https://rntfnd.org/wp-content/uploads/Aviation-GNSS-interfer...:

  • GPS Problem reports dominate over all other type of safety reports
  • Redundant systems are the only reason why aviation has been able to
    maintain normal operations despite GNSS RFI!
  • GNSS integrated into many systems; exact RFI impact difficult to
    predict, manufacturers had to issue aircraft specific
    guidance → Complexity and workload increase

  Aviation Safety Impact
  • Aviation Safety is built on two main principles:
  • Trust your instruments
  • Follow standard operating procedure
  • GNSS RFI causes pilots to have to question both principles!
  • Chief Operations Officer of one major airline:
    Navigation is not my problem. My problem is “normalization of
    deviance”!
  • Incidents have occurred simply due to pilot distraction because of
    having to deal with too many system alerts

The U.S. military jamming GPS of civilian aircraft is a situation where there have been several close calls before this incident and experts have been saying for years that if the military keeps doing this, even with NOTAMs, people will get hurt and then that prediction tragically came true.

From 2021, "FAA Files Reveal a Surprising Threat to Airline Safety: The U.S. Military GPS Tests" https://spectrum.ieee.org/faa-files-reveal-a-surprising-thre...:

  Early one morning last May, a commercial airliner was approaching El
  Paso International Airport, in West Texas, when a warning popped up in
  the cockpit: “GPS Position Lost.” The pilot contacted the airline’s
  operations center and received a report that the U.S. Army’s White
  Sands Missile Range, in South Central New Mexico, was disrupting the
  GPS signal. “We knew then that it was not an aircraft GPS fault,” the
  pilot wrote later.

  The pilot missed an approach on one runway due to high winds, then
  came around to try again. “We were forced to Runway 04 with a predawn
  landing with no access to [an instrument landing] with vertical
  guidance,” the pilot wrote. “Runway 04…has a high CFIT threat due to
  the climbing terrain in the local area.”

Also

  This is far from the most worrying ASRS report involving GPS jamming.
  In August 2018, a passenger aircraft in Idaho, flying in smoky
  conditions, reportedly suffered GPS interference from military tests
  and was saved from crashing into a mountain only by the last-minute
  intervention of an air traffic controller. “Loss of life can happen
  because air traffic control and a flight crew believe their equipment
  are working as intended, but are in fact leading them into the side of
  the mountain,” wrote the controller. “Had [we] not noticed, that
 flight crew and the passengers would be dead. I have no doubt.”

Here's what an air traffic controller with 18 years of experience wrote about WSMR GPS interference in 2024: "Someone will get hurt ignoring the pilot reports or deciding for pilots how much equipment can fail or be unreliable before they 'agree' or decide to stop GPS jamming." https://asrs.arc.nasa.gov/docs/rpsts/ctlr.pdf