Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Civilian plane crash in New Mexico tied to military GPS blocking

wired.com

Post reply on HN
Print view View original

291–295 of 295 posts

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

#291

Post by cdot2 »

alistairSH wrote: post #227
cdot2 wrote: post #210

Earlier quoted context omitted.

" acknowledging that doing so changes the risk profile of aviation to some extent" Isn't that what the NOTAM is?

Clearly the NOTAMs aren't doing the job, as this isn't the only instance of issues. It's just the only instance of a crash with fatalities.

So they should turn off the GPS interference whenever they're asked to do so by ATC. Which they did in this case. The timeline is something like , NOTAM issued, flight takes off, flight has issues, ATC asked the military to turn off the interference, the military complies, the flight says they're good now and the interference can continue, ATC informes the military that they can continue, they do, and then the flight crashes. I don't see how the military carries any fault here.

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

#293

Post by dpe82 »

cmurf wrote: post #257
dpe82 wrote: post #231

Earlier quoted context omitted.

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

Yes, but… They are enhancing the navaids that remain. Greater range, and a documented network of airports serviced by ground based instrument approach procedures. The shrinkage of total number of navaids concerns me from a rural support perspective but less so as a pilot. What does concern me as a pilot is even the MON navaids are having maintenance issues resulting in outages.

> even the MON navaids are having maintenance issues resulting in outages

Which is exactly why we previously had such a dense network: to provide redundancy in the face of inevitable outages.

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

#294

Post by arcfour »

cdot2 wrote: post #210
alistairSH wrote: post #200

Earlier quoted context omitted.

You're not wrong, but that doesn't necessarily mean Uncle Sam should be dicking around with GPS jammers as a normal thing (at least not without acknowledging that doing so changes the risk profile of aviation to some extent).

" acknowledging that doing so changes the risk profile of aviation to some extent" Isn't that what the NOTAM is?

That's like saying "what, it was published in the paper of record in your local area!"

NOTAMs have so many issues it's not even funny. There's so many of them and 9/10 of them are irrelevant for one.

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

#295

Post by cmurf »

cmurf wrote: post #146
SoftTalker wrote: post #106

Earlier quoted context omitted.

If you are a pilot and can't handle GPS dropping out, or the failure of any other single navigation aid, you should not be flying.

In general I agree with this. (Without respect to this particular crash.) If GPS signal is sufficiently degraded or lost, TAWS is probably unavailable (highly dependent on what navigation system is on board). TAWS might have saved them. But needing TAWS implies loss of situational awareness. This flight crashed in the mountains ~6 miles north of the ILS 24 approach course. At ~12 miles out on the approach course, the…

Ok after rereading the preliminary report, ATC gave them a vector north and clearance to a named fix. They were not off course. While on a vector clearance, terrain and obstacle clearance is ATC's responsibility.

Once the accident flight requested and received a visual approach clearance ~30 miles out, terrain and obstacle avoidance becomes pilot responsibility. It seems likely to me that whether GPS was working or not, whether RNAV 24 or ILS 24, they'd have requested a visual approach. And the pilots did not adequately account for the terrain between the flight and the airport when they initiated the descent, and descended below minimum safe IFR altitude.

Further due to this flight operating under 14 CFR 135, there's a regulatory bridge to bind the flight to the (Part 135) Certificate Holder's operation specifications (OpSpecs). Pilots cannot operate outside of OpSpecs.

It's possible the medivac company's OpSpecs require mandatory direct visual contact with terrain and obstacles - something that could not be achieved with 0% illumination due to no moon. Some OpSpecs will prohibit visual approaches at night to non-towered airports. SRR airport has no tower. I'm not familiar with this operator's OpSpecs.

Post reply on HN