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Civilian plane crash in New Mexico tied to military GPS blocking

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Re: Civilian plane crash in New Mexico tied to military GPS blocking

#231

Post by dpe82 »

jjwiseman wrote: post #179

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.…

Another thing to add to all this is FAA has been steadily removing from service non-GPS navigation aids.

Re: Civilian plane crash in New Mexico tied to military GPS blocking

#232

Post by XorNot »

PhaedrusV wrote: post #228
jjwiseman wrote: post #179

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.…

The problem here is the assumption that if the US mil weren’t jamming GPS it wouldn’t be getting jammed. GPS is trivially easy to jam for any state actor, and it’s not “macho” to say that pilots always need to be able to safely conduct flights in its absence.

The US military over US territory are the only ones who can jam GPS at the scale being talked about.

Anyone else firing up a jammer is going to get triangulated and arrested very quickly.

Re: Civilian plane crash in New Mexico tied to military GPS blocking

#233

Post by inoffensivename »

scott00 wrote: post #207
inoffensivename wrote: post #84

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 w…

Would using the ILS without the local altimeter actually be a safe way to land the plane? (Ignoring whether or not ATC is allowed to give you clearance for that.) Is the requirement of a local altimeter just overly cautious?

Yes, safe, and also way safer than doing a visual approach without any backup at night. Like the other commenter said, the local altimeter setting is only required for knowing when you arrive at Decision Altitude, which is not applicable for this visual approach.

I'm not sure of ATC's rules, but my assumption is that they would NOT clear me for an ILS approach in this circumstance. But that's moot, I would not ask for it because it's not authorized anyway. It would be a visual approach, we'd just happen to fly the ILS course and use the GS for vertical guidance.

Re: Civilian plane crash in New Mexico tied to military GPS blocking

#234

Post by _moof »

Lack of GPS was one factor here, but poor judgment was the real killer. Flying a visual approach at night into a field surrounded by unlit mountains is suicidal.

There's a saying among medevac pilots when it comes to making go/no-go decisions: don't turn one tragedy into five.

Re: Civilian plane crash in New Mexico tied to military GPS blocking

#235

Post by _moof »

scott00 wrote: post #207
inoffensivename wrote: post #84

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 w…

Would using the ILS without the local altimeter actually be a safe way to land the plane? (Ignoring whether or not ATC is allowed to give you clearance for that.) Is the requirement of a local altimeter just overly cautious?

It would not be safe at this airport, and the ILS procedure there explicitly forbids it. In the remarks at the top of the approach plate you'll see "When local altimeter setting not received, procedure NA." (NA = Not Authorized.) Here's the plate: https://aeronav.faa.gov/d-tpp/2607/06922IL24.PDF

The reason you need an accurate altimeter for this ILS is that the obstacle clearance surface for the intermediate segment - the part where you're flying straight and level without a glideslope - lies atop the very mountains these pilots crashed into. Vertical guidance on the missed approach is also barometric, and there are mountains in that direction too.

Re: Civilian plane crash in New Mexico tied to military GPS blocking

#236

Post by franktankbank »

XorNot wrote: post #232
PhaedrusV wrote: post #228

Earlier quoted context omitted.

The problem here is the assumption that if the US mil weren’t jamming GPS it wouldn’t be getting jammed. GPS is trivially easy to jam for any state actor, and it’s not “macho” to say that pilots always need to be able to safely conduct flights in its absence.

The US military over US territory are the only ones who can jam GPS at the scale being talked about. Anyone else firing up a jammer is going to get triangulated and arrested very quickly.

I think the GP assumption is that there is a bad actor intent on serious harm.

I'm not really sure where I side on this.

Ideally Defense would be able to conduct exercises without worrying about harming civilians. But that seems impossible to drive to 0.

I think the top level commenter comes across as a bit one sided. How often is due-diligence done by the pilots? Could the guidance provided be more well defined and reduce these incidences to several orders of magnitude less? Hopefully the military is not purposefully inflating incidences for nefarious purposes or instigating specific instances.

Re: Civilian plane crash in New Mexico tied to military GPS blocking

#237

Post by _moof »

sokoloff wrote: post #222
scott00 wrote: post #207

Earlier quoted context omitted.

Would using the ILS without the local altimeter actually be a safe way to land the plane? (Ignoring whether or not ATC is allowed to give you clearance for that.) Is the requirement of a local altimeter just overly cautious?

It would be safe. The ILS projects a localizer signal (left/right deviation compared to runway alignment) and glideslope signal (up/down deviation versus the intended flight path, usually about 3°). The only thing you need a precision altimeter setting for is to determine the safe decision altitude (point at which you need to see the runway environment to continue, else initiate a missed approach) and a fairly theore…

Not true. You also need an accurate altimeter to fly the intermediate segment, as well as the missed approach segment. There are mountains under the obstacle clearance surfaces on both segments. That is why this ILS procedure is explicitly not authorized when the local altimeter setting isn't available.

Re: Civilian plane crash in New Mexico tied to military GPS blocking

#239

Post by 27183 »

Zak wrote: post #220
SoftTalker wrote: post #148

Earlier quoted context omitted.

I'm not a pilot but as I understand it, stall/spin recovery practice is not mandatory anymore for a PPL and not all pilots do it, because it requires an aircraft designed for acrobatics and in practice a number of pilots ended up getting killed trying it. So now they learn it by the book or maybe playing with a flight simulator but not in an actual aircraft.

Not a pilot either, but it's my understanding that accidental spins almost never happen at altitudes where they're recoverable. Preventing the spin is the only way to avoid most crashes involving spins. Stalls, on the other hand are part of standard instruction. Recognizing the beginning of a stall early and preventing it will prevent the spin.

Weird things can happen with big downdrafts and wind shear, but those aren't terribly frequent and probably a spin is less critical to practice than stall recovery. But it's a very different experience to actually feel the forces and see the world spinning than you get in a sim. Also it's a lot of fun.

Re: Civilian plane crash in New Mexico tied to military GPS blocking

#240

Post by _moof »

inigyou wrote: post #175
seatac76 wrote: post #35

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.

Luckily, aviation investigations haven't concluded with "pilot error" for over half a century, or else there would be a lot more accidents as we never fixed any of the actual causes and just blamed the dead pilots.

I'm sorry, what? Pilot error is absolutely a factor in contemporary accidents. It's the most common one, in fact, because we've rooted out almost all the other risks.
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