4 ms·

The terminology made me think that they just had a VHF receiver up there and were listening to AIS traffic https://en.wikipedia.org/wiki/Automatic_identificatio

The terminology made me think that they just had a VHF receiver up there and were listening to AIS traffic https://en.wikipedia.org/wiki/Automatic_identification_system https://en.wikipedia.org/wiki/Automatic_identification_syste... It's similar to the ADS-B systems that airplanes use to report their location and altitude and heading. AIS has a built-in messaging system for ship-to-ship communications and to receive alerts. You can detect AIS traffic from satellite, but ground-based antennas are cheaper and more sensitive. Having a aerostat to increase range would be good for monitoring maritime traffic over a larger area. UPDATE: After reading some more, I think this is a perfect fit for AIS monitoring. Ground-based solutions have a horizon limitation of 46 miles. Satellite systems get overwhelmed with too many ships reporting in and data is lost. A balloon based system would be in a sweet spot where it would allow the US to extend the AIS monitoring a few hundred miles out from the borders while not having to put more satellites into orbit.

mdekkers 9y ago
Global AIS traffic is publicly available: https://www.marinetraffic.com/ https://www.marinetraffic.com/
mmjaa 9y ago
Nothing in the article indicates that they are 'only spying on AIS traffic' - this is an assumption, and a poor guess, possible diversion tactic, at best.
- willstrafach 9y ago
  The source material linked in the article (SIDtoday newsletter) is what states it was used for AIS traffic. I am curious as to what else you believe it is used for?
  - logfromblammo 9y ago
    I'd guess they were monitoring every signal from radio bands that have a line-of-sight or one-bounce range limitations, as they could get the rest of the spectrum from their ground-based antennas. They're experts in signals intelligence and have no practical budget limitations. They're recording everything, automatically processing to find the interesting bits, and assigning real life humans to look at those interesting bits. I'm guessing that in the NYC area, at the very least Russia, China, and Canada are sucking up the same EM signals, or trying to. We mere mortals tend to assume that such a tool would be used for one thing in particular, because don't have cults of patriotism or bottomless bank accounts.
  - 1001101 9y ago
    We've had these blimps over our landlocked midwestern city. The largest ships in our area are 24' Sea Rays on a lake, nowhere near the gross tonnage that mandates use of AIS. We may have to accept that the true nature of these blimps is shrouded under layers of state secrecy, and all we have left is speculation based on observation.

mdekkers 9y ago

Global AIS traffic is publicly available: https://www.marinetraffic.com/ https://www.marinetraffic.com/

mmjaa 9y ago

Nothing in the article indicates that they are 'only spying on AIS traffic' - this is an assumption, and a poor guess, possible diversion tactic, at best.

willstrafach 9y ago
The source material linked in the article (SIDtoday newsletter) is what states it was used for AIS traffic. I am curious as to what else you believe it is used for?
- logfromblammo 9y ago
  I'd guess they were monitoring every signal from radio bands that have a line-of-sight or one-bounce range limitations, as they could get the rest of the spectrum from their ground-based antennas. They're experts in signals intelligence and have no practical budget limitations. They're recording everything, automatically processing to find the interesting bits, and assigning real life humans to look at those interesting bits. I'm guessing that in the NYC area, at the very least Russia, China, and Canada are sucking up the same EM signals, or trying to. We mere mortals tend to assume that such a tool would be used for one thing in particular, because don't have cults of patriotism or bottomless bank accounts.
- 1001101 9y ago
  We've had these blimps over our landlocked midwestern city. The largest ships in our area are 24' Sea Rays on a lake, nowhere near the gross tonnage that mandates use of AIS. We may have to accept that the true nature of these blimps is shrouded under layers of state secrecy, and all we have left is speculation based on observation.