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.").
• 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.
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
jjwiseman
When I used to fly in Florida in the 2005-2015ish timeframe, NOTAMs for GPS interference (it didn't say that exactly but that's what it meant) were an everyday occurrence along my path, it became boilerplate. I experienced it a few times. One moment the GPS thinks you're plodding along next to Ocala, next moment it thinks I've teleported a thousand miles away, and then it'd just quit.
But that's what we train for. That's why aircraft and pilots have redundancy to work around any single possible point of failure and why you practice it until it becomes natural. Because of the NOTAM I'd already have a VOR tuned in, and once the GPS went inop I just fine tuned it to get a radial fix on the VOR. Also tried to never lose my bearings with my MK I Eyeballs either. No big deal.
I feel bad for everyone that lost their lives here, but this is why competence is critical. There's a litany of errors the pilots made. And the article tries to pin a bit on the controller, but no, ultimate responsibility is on the pilot in command, FAR/AIM is clear on that.
If these allegedly instrument rated pilots had been properly drilled by their CFI's and properly grilled during reviews and such this should've been an easy flight.
Also, "just ask Kennedy". Wired bringing that into the conversation is perhaps relevant but not in the way I think they intended. JFK Jr lacked basic airmanship skills. His aircraft was 100% functional until the moment it impacted the ocean.
Some professions simply can't be go-along-to-get-along social clubs. Safety culture centered on competence and performance is key.
mrngld
Airline captain here... A visual approach to an airport in mountainous terrain on a moonless night is very risky.
In our operation, departing to an airport with missing weather reports would not be permitted, so in a Part 121 scheduled service this flight may not have been able to dispatch legally.
Airliners have DME/DME triangulation which allows them to achieve area navigation (RNAV) without GPS. The interference would have precluded a GPS approach but may have left the GPWS ("Terrain! Terrain!") alerts unaffected.
In this case the ILS was not available, but only because the local altimeter setting was not available. In this case I could accept a visual approach, but use the ILS to provide lateral and vertical guidance towards the runway.
There are many things I have learned about flying from years at the airlines that I would have had to learn the hard way at a Part 135 or Part 91 operation. One of those things would have been when to say "no".
Take the airplane to a mountainous airport with missing weather reports at night with NOTAM'd GPS interference? No.
Do a visual approach on a moonless night with no GPS for terrain awareness? No. Fly the ILS even if it's NOTAM'd out.
inoffensivename
GPS is not essential to air navigation. It’s nice to have, and there are some approaches that legally require it to be operational in order to fly them (IFR procedures) but aviation has other systems in place to guide aircraft under conditions where visual flight navigation is impossible.
In this case, IMHO, the pilots had become complacent and lax in their navigational rigor because of the fact that GPS makes a lot of the slightly less automated systems unnecessary, and people get used to that workflow.
If the flight crew had been looking at their map and using it to inform them about the mountains in their path, fixing position by the VOR and DME, or even just a stopwatch and compass heading, they would have easily known they needed to be at a higher altitude. Not being precisely sure of their exact position, they should have at least been maintaining the minimum safe altitude for the area they knew they were in.
But unfortunately, people get so used to looking at the shiny screen giving them effortless situational awareness that they forget all of the rules and habits that kept pilots alive for the last century before glass cockpits were a thing, and they forget that mountains are the tigers of the air, always waiting to catch pilots unaware.
This is a useful cautionary tale not only for pilots, but increasingly for humans in general as we become accustomed to a new kind of instrument that allows us to offload a great deal of our cognitive focus to a tool that may sometimes fail.
K0balt
Missing from the article is that, once the pilots reported to ATC that GPS was inoperable, ATC was going to have them circle to the right and guide them along the ILS approach, which would've avoided the worst of the mountains. ATC also asked the military to stop GPS jamming, which they did for a brief while... and the pilots probably noticed GPS start working again... except...
Instead, the pilots saw the airport visually and requested a visual approach. ATC cleared them, and told the military they could resume GPS jamming, meaning any terrain awareness warning system the pilots might have had or been relying on would no longer work. The visual approach involved a left turn and descending directly over the mountains.
He focuses on the fact that both instrument approaches were impossible under the conditions; gps jamming made RNAV impossible, and an inoperable weather broadcasting system at the destination made ILS impossible. The alternative, visual approach in mountainous terrain on a moonless night, is clearly unwise for inexperienced pilots.
One thing he doesn't mention, though, is that ATC could have waited until the plane was on the ground to tell the military they could resume GPS jamming, knowing this was a medevac flight lacking the usual planning and level of caution of typical pilots.
harshreality
The animation at the top is worryingly misleading. The airplane that crashed was a Beechcraft twin turboprop, and the plane maneuvered a couple of times before crashing. It had 4 people inside it.
The animation uses what looks like an airliner, and shows the jamming as a sort of bubble that directly sends the airplane into a crash.
I found it disturbing when I looked at it, it does not represent the story well, and I think that's irresponsible.
I actually experienced GPS spoofing while paragliding near Ukraine, luckily in the daytime. I don't even want to imagine it at night on a rescue mission. Condolences to the occupants.
It's quite easy to say "no big deal" while calm in an office, but it's really different when you're busy flying and then there's the extra workload of trying to understand what's happening, attempting to fix it, and so on. Imagine "debug bug in production while driving a car" for a rough comparison, although I guess planes are probably better equipped for loss of GPS?
The loss is tragic but I’m sorry GPS jamming was not a factor here. There was a NOTAM indicating it’s going on, the pilots should have been aware and it appears when they reached out with a request the jamming was stopped.
It was a visual approach at a moonless night at an airport in high terrain, this was pilot error unfortunately.
comments (10)
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...:
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...:
Also 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.pdfjjwiseman
But that's what we train for. That's why aircraft and pilots have redundancy to work around any single possible point of failure and why you practice it until it becomes natural. Because of the NOTAM I'd already have a VOR tuned in, and once the GPS went inop I just fine tuned it to get a radial fix on the VOR. Also tried to never lose my bearings with my MK I Eyeballs either. No big deal.
I feel bad for everyone that lost their lives here, but this is why competence is critical. There's a litany of errors the pilots made. And the article tries to pin a bit on the controller, but no, ultimate responsibility is on the pilot in command, FAR/AIM is clear on that.
If these allegedly instrument rated pilots had been properly drilled by their CFI's and properly grilled during reviews and such this should've been an easy flight.
Also, "just ask Kennedy". Wired bringing that into the conversation is perhaps relevant but not in the way I think they intended. JFK Jr lacked basic airmanship skills. His aircraft was 100% functional until the moment it impacted the ocean.
Some professions simply can't be go-along-to-get-along social clubs. Safety culture centered on competence and performance is key.
mrngld
In our operation, departing to an airport with missing weather reports would not be permitted, so in a Part 121 scheduled service this flight may not have been able to dispatch legally.
Airliners have DME/DME triangulation which allows them to achieve area navigation (RNAV) without GPS. The interference would have precluded a GPS approach but may have left the GPWS ("Terrain! Terrain!") alerts unaffected.
In this case the ILS was not available, but only because the local altimeter setting was not available. In this case I could accept a visual approach, but use the ILS to provide lateral and vertical guidance towards the runway.
There are many things I have learned about flying from years at the airlines that I would have had to learn the hard way at a Part 135 or Part 91 operation. One of those things would have been when to say "no".
Take the airplane to a mountainous airport with missing weather reports at night with NOTAM'd GPS interference? No.
Do a visual approach on a moonless night with no GPS for terrain awareness? No. Fly the ILS even if it's NOTAM'd out.
inoffensivename
In this case, IMHO, the pilots had become complacent and lax in their navigational rigor because of the fact that GPS makes a lot of the slightly less automated systems unnecessary, and people get used to that workflow.
If the flight crew had been looking at their map and using it to inform them about the mountains in their path, fixing position by the VOR and DME, or even just a stopwatch and compass heading, they would have easily known they needed to be at a higher altitude. Not being precisely sure of their exact position, they should have at least been maintaining the minimum safe altitude for the area they knew they were in.
But unfortunately, people get so used to looking at the shiny screen giving them effortless situational awareness that they forget all of the rules and habits that kept pilots alive for the last century before glass cockpits were a thing, and they forget that mountains are the tigers of the air, always waiting to catch pilots unaware.
This is a useful cautionary tale not only for pilots, but increasingly for humans in general as we become accustomed to a new kind of instrument that allows us to offload a great deal of our cognitive focus to a tool that may sometimes fail.
K0balt
Instead, the pilots saw the airport visually and requested a visual approach. ATC cleared them, and told the military they could resume GPS jamming, meaning any terrain awareness warning system the pilots might have had or been relying on would no longer work. The visual approach involved a left turn and descending directly over the mountains.
blancolirio's video about this (second one, after the prelim investigation report): https://www.youtube.com/watch?v=Dcyup4xVQuM
He focuses on the fact that both instrument approaches were impossible under the conditions; gps jamming made RNAV impossible, and an inoperable weather broadcasting system at the destination made ILS impossible. The alternative, visual approach in mountainous terrain on a moonless night, is clearly unwise for inexperienced pilots.
One thing he doesn't mention, though, is that ATC could have waited until the plane was on the ground to tell the military they could resume GPS jamming, knowing this was a medevac flight lacking the usual planning and level of caution of typical pilots.
harshreality
The animation uses what looks like an airliner, and shows the jamming as a sort of bubble that directly sends the airplane into a crash.
I found it disturbing when I looked at it, it does not represent the story well, and I think that's irresponsible.
brainlessdev
jcalvinowens
rbanffy
It's quite easy to say "no big deal" while calm in an office, but it's really different when you're busy flying and then there's the extra workload of trying to understand what's happening, attempting to fix it, and so on. Imagine "debug bug in production while driving a car" for a rough comparison, although I guess planes are probably better equipped for loss of GPS?
https://blog.emilburzo.com/2026/06/gps-spoofing-teleported-m...
emilburzo
It was a visual approach at a moonless night at an airport in high terrain, this was pilot error unfortunately.
seatac76