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NEWS Waterfront property in the Spratlys? Good investment or not?

Gatordev said:
I wasn't sure where to put this, so it goes here for now...

I've made comments before about my concerns on how delicate our current iteration of GPS/GNSS is as it relates to our war-fighting capability and this video is a great open-source example of why. It's a little long but interesting.


I didn't realize our current GPS requires celestial navigation to function. In hindsight it makes sense, but I don't remember hearing that before (or I've forgotten it).
Click to expand...

As an old Nav who actually learned celestial in flight school in addition to the other old ways to wander around the world, GPS resiliency has long been a concern of mine. I know that there is a lot of resiliency and redundancy built in to the system but I've often wondered if it is enough. I'm certainly not alone in being concerned, there is plenty of ink out there on its vulnerabilities and what should be done to strengthen the system and increase backups and alternatives. In the meantime I doubt enough will be done unless something catastrophic happens.
 
Flash said:
As an old Nav who actually learned celestial in flight school in addition to the other old ways to wander around the world, GPS resiliency has long been a concern of mine. I know that there is a lot of resiliency and redundancy built in to the system but I've often wondered if it is enough. I'm certainly not alone in being concerned, there is plenty of ink out there on its vulnerabilities and what should be done to strengthen the system and increase backups and alternatives. In the meantime I doubt enough will be done unless something catastrophic happens.
Click to expand...

Even in .civ world, spoofing and jamming are becoming more common. This, even as our systems are increasingly reliant on GPS and maintenance of ground-based navigation systems is winding down.

I think we might be one orbital-denial event or accident away from catastrophe, but I would be happy to be proven wrong.
 
sevenhelmet said:
Even in .civ world, spoofing and jamming are becoming more common. This, even as our systems are increasingly reliant on GPS and maintenance of ground-based navigation systems is winding down.

I think we might be one orbital-denial event or accident away from catastrophe, but I would be happy to be proven wrong.
Click to expand...
With 31 satellites currently in orbit, you'd need to take out 8 of them before any real degradation in coverage occurred... not that this couldn't be deliberately carried out, but a lot would have to go wrong for an accidental disruption of this magnitude.
 
Brett327 said:
With 31 satellites currently in orbit, you'd need to take out 8 of them before any real degradation in coverage occurred... not that this couldn't be deliberately carried out, but a lot would have to go wrong for an accidental disruption of this magnitude.
Click to expand...

That's consistent with the apparent conclusion that GPS is robust enough to rely on for most things. However, its susceptibility to jamming and/or spoofing is still an issue.
 
Brett327 said:
With 31 satellites currently in orbit, you'd need to take out 8 of them before any real degradation in coverage occurred... not that this couldn't be deliberately carried out, but a lot would have to go wrong for an accidental disruption of this magnitude.
Click to expand...
It is interesting to me that non-mil aviation is not in a multi GNSS world for redundancy. GPS/NAVSTAR is the order of the day

My motorcycle GPS Nav uses all the constellations....
 
ChuckMK23 said:
It is interesting to me that non-mil aviation is not in a multi GNSS world for redundancy. GPS/NAVSTAR is the order of the day

My motorcycle GPS Nav uses all the constellations....
Click to expand...

Some civilian airplanes do make use of other constellations, particularly Galileo and GLONASS. I haven't worked with any systems that use BeiDou. The ones that only use GPS (e.g. Garmin panels) use a backup system such as DME from known navaids, inertial navigation, or dead-reckoning. The bigger threat is spoofing, which can result in more subtle indications that something is wrong, particularly when you can't look out the window and see the error. We have had several incidents of this noted within the company. Fortunately, all have been real-time apparent and did not result in any incidents (so far). It's not hard to see how they might.

Bottom line: If something is flagged, it's for a reason. Don't trust only one system- have a backup plan.

I think there are real conversations to come about hardening GPS-based systems against ground-based spoofing. Interestingly, a lot of mobile devices can access multiple constellations, and while they can be more sensitive to interference than certified aircraft systems, they also sometimes recover more quickly. I once flew a leg from Greenland to Iceland where we lost aircraft GPS- likely due to localized jamming- and reverted to inertial-navigation about 45 minutes into a 3 hour flight (over water just East of Greenland). We elected to continue based party on the fact that our mobile devices recovered, so we were able to cross-check our IRS and verify its accuracy, and ask for vectors for an ILS at BIKF to eliminate any navigational errors.

Still- eerie to be over the big water in a single engine airplane (AT-6) and have no GPS. Of note, the accumulated inertial error after about 2 hours was less than 0.7 nautical miles. Good enough to get there.
 
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sevenhelmet said:
BIKF
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Haven't heard that ICAO identifier in a while. Fun story, during an early 90s P-3C deployment to Kef, one of our crews lost their Nav solution while on station and had to DR their way home over a three hour transit. Mind you this was pre-GPS and both the Litton INS systems had crashed somehow and CELNAV wasn't an option due to cloud cover. Long story short, they missed Iceland and flew north of it and had to do DF cuts with the HF radio to eventually get headed in the right direction. Fortunately, the on top fuel requirements for Kef was really high, so they had enough time to figure things out, but that could have been a much worse day.
 
Brett327 said:
Haven't heard that ICAO identifier in a while. Fun story, during an early 90s P-3C deployment to Kef, one of our crews lost their Nav solution while on station and had to DR their way home over a three hour transit. Mind you this was pre-GPS and both the Litton INS systems had crashed somehow and CELNAV wasn't an option due to cloud cover. Long story short, they missed Iceland and flew north of it and had to do DF cuts with the HF radio to eventually get headed in the right direction. Fortunately, the on top fuel requirements for Kef was really high, so they had enough time to figure things out, but that could have been a much worse day.
Click to expand...

Missing Iceland would suck- justification for those high bingo #s. We were faced with a choice between trusting our IRS (which is pretty reliable) backed up with handheld devices, or turning back to a closed airport with 6000' peaks on three sides in a non-radar environment. Made sense to continue.
 
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