Ship location question

Discussion in 'Amateur Radio General Discussion' started by Tony, Mar 2, 2017.

  1. Tony

    Tony Moderator Staff Member

    Here's a question that I presume Jeremy will be able to answer

    I tripped across a web site, , that shows ship positions as an aid for other ships, and even pleasure craft.

    Didn't I read here that companies don't want APRS used so their position is not revealed for safety? How does that square with the use of Automatic Identification System?
  2. Jeremy

    Jeremy Active Member

    AIS uses the marine VHF band for position and messaging. It is very similar to APRS in function, but slightly different in form. In any case, to answer Tony's question, the use of AIS as a safety measure outweighs the security concerns. It is also has an economic angle, as the brokers track the location of different kinds of ships to see where they are.

    The use of AIS by commercial ships, and its IGating to the internet is why I felt comfortable broadcasting my HF APRS beacons on my former ship; except when in piracy areas, where many ships secure their AIS out of an abundance of caution. My current ship is under charter by the USN and they want our AIS use to be fairly limited. In response to that policy, I don't broadcast position data from this ship while underway. I will however, use the messaging function as it does not reveal my position.

  3. Tony

    Tony Moderator Staff Member

    Ah, Ok. Thanks, Jeremy. You changed ships. I thought you were still on the old one and that the company changed policy.

    And the navy has to contract ships. Don't they have enough of their own? :)
  4. Jeremy

    Jeremy Active Member

    USN not using AIS is considered a factor in the recent slew of collisions. I think that poor radar signature is also part of the equation.
  5. Tony

    Tony Moderator Staff Member

    I do wonder, however, why the navy people are not watching. What else do they have to do?

    Even we pleasure sail-powered skippers must keep vigilant watch, if we know what's good for us, when sailing especially at night on Lake Erie. One time, just once, I wasn't watching, and a merchant vessel almost ran over me in New York waters of Lake Erie. And that was well out of the shipping lanes. I have no idea why he was out of the shipping lane. I learned immediately why he did not see our radar reflector. He said his radar was off.

    So I learned to be even more vigilant on Lake Erie.

    Why doesn't the navy know that since U.S. ships are stealthy for good reason?
  6. Jeremy

    Jeremy Active Member

    My professional opinion, based on what I have read (and that means I don't have the hard, original data) is that it was a combination of chronic fatigue, lack of experience on the part of the bridge team, and information overload that lead to the collisions.
  7. Tony

    Tony Moderator Staff Member

    Maybe somebody is trying to save a dime and overworking the bridge team, and not leaving enough time for adequate training.

    I have read that the military management now sees GIs as pensions.
  8. Jeremy

    Jeremy Active Member

    From what I've learned from people who are SWO's, they have training, meetings, and paperwork to complete during the "off time" and they use a "5 and dime" watch schedule which means 5 on, 10 off, 2 on, 2 off, 5 on, 10 off. Then they switch every other day. It's a terrible schedule, especially when those 10 hours are full of non watching standing work. Also problematic is that the senior officer's aren't career SWO's so may have very limited time on the bridge and therefore prone to errors.


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