GPS jamming by the military has been cited in the crash of an air ambulance in New Mexico last month. In its preliminary report on the crash, which killed both pilots and two nurses on the King Air, the NTSB says the crew repeatedly lost GPS service as they tried to get to Sierra Blanca Regional Airport to pick up a patient. They finally requested an ILS approach to the field. After notifying ATC they had the field in sight, they asked for a visual approach and crashed about 230 feet below the peak of the Capitan Mountains. “GPS jamming activities that encompassed the area around the accident flight were being conducted by the United States military during the time of the flight,” the report says.
Jamming regularly occurs in that part of the country, and ATC was in contact with the military personnel conducting the tests. Twice ATC asked the military to stop jamming, and at least three other aircraft in the same area also reported losing GPS. After the air ambulance crew said they had started a visual approach, the controller called the military and told them they could start jamming again. The crash occurred about five minutes later. There was a NOTAM for the jamming and the crew had received the information via ForeFlight.
If they had the field in site as reported, then what should the GPS have had to do with them being too low that far out? Unless they were head in the cockpit and task saturated trying to get the GPS back online to set up for the ILS approach they had requested. Given two competent pilots, I’m scratching my head on this one.
Sounds like the GPS jamming didn’t have much to do with this one. The final line says it all. Without local altimeter setting both approaches were NA.
My only thought is that most TAWS systems are GPS-based, and theirs was therefore unable to give the crew warning that they were approaching terrain. It is still the crew’s responsibility to maintain appropriate altitude, of course, but perhaps having GPS could have helped.
True. Anytime an approach is NA at night or without local altimeter setting, that should be a BIG red flag for obstacles and briefed accordingly. Having the airport in sight doesn’t guarantee you won’t hit something in the descent. I’m reminded of the February Epic crash in Steamboat …
I’m guessing that they were based in Roswell and should, therefore, been well aware of the terrain.
I also thought that it’s a straight shot west on the highway without any mountain flying. I’d do that in the day time (quicker) but not at night.
I’ve had several occasions where the Garmin stuff goes brain dead from jamming or spoofing, but my Sentry/iPad continued to navigate. Why? “Sentry has a built-in WAAS GPS that also supports the Galileo, GLONASS, and Beidou satellite constellations, with support for up to three simultaneous connections for enhanced GPS reliability.”
From my experience, this feature works, but is little advertised or discussed. It would be nice to see an in-depth article on this topic.
Exactly. GPS jamming makes at least some Garmin panels go absolutely crazy. I have had it in both a Phenom 100 and a Phenom 300 on multiple occasions. It’s not just a loss of navigation. You get red and yellow flags all over every display, it kicks the autopilot off and you’re down to hand flying the airplane where you can depend on nothing.
Hand flying – Horrors!
I love hand flying. But what does Garmin say to do with multiple instrument failures? ADC? AHRS? And whatever else is failed while you’re trying to shoot an approach?
I have no idea what Garmin says, nor do I care. I always enjoyed partial panel flying but, since I don’t fly IFR any more, it’s a moot point.
Thanks for the warning.
No doubt, Garmin and the others are perfectly capable of also using other constellations as a backstop to USA GPS. Where’s the TSO for that? Where’s the motivation for any bureaucrat at the FAA for creating one? Perhaps after a few airliners auger in the motivation will happen, but I doubt it will happen within my remaining lifetime. How many light planes crashed due to antique magneto failures before the feds allowed electronic ignition? Response time is 50+ years after the alternative tech becomes available.
Regardless of whether GPS jamming directly caused this accident, all pilots should be aware that they can call for a stoppage of military GPS jamming by calling “Stop buzzer, stop buzzer, stop buzzer” on 121.5
I’m just wondering what is going to happen when a jammer hits a fly by wire airplane with no mechanical backups or direct flight control linkage?
Nothing–or more specifically, the same thing that would happen to a pulley-and-cable airplane. The FBW, and the IRUs and air data systems that feed the FBW don’t depend on GPS.
Yes, and forbid the thought that a military jamming expert would ever invent something that jams more than just GPS.
Highly improbable. The newest certification standards require testing to HIRF and lightning impulse levels which are technically extremely difficult to attain at any realistic distance to the aircraft. For example, FBW needs to operate when an aircraft flies right by the antenna of a multi-megawatt RADAR transmitter. Concentrate on pilot skills and worry less about the electronics being intentionally jammed. Reference RTCA DO-160G.
I have flown that ILS into KSRR and the approach is, indeed, long and high at the beginning. That said, they should not have been below 11,000 until glide slope intercept. Assuming the crew was based at Roswell, they should have been well aware of the terrain that they were flying over.
I see no way to blame a GPS outage for this accident, had they actually been flying the published approach. RIP, all.