BoatBanter.com - Boat crash in Ft. Lauderdale

On Sat, 4 Jan 2020 05:37:06 -0000 (UTC), Bill
wrote:

wrote:
On Fri, 03 Jan 2020 17:22:56 -0500, wrote:

On Fri, 03 Jan 2020 15:06:00 -0500,
wrote:

On Fri, 03 Jan 2020 13:31:42 -0500, wrote:

On Fri, 3 Jan 2020 07:00:02 -0500, "Mr. Luddite"
wrote:

On 1/2/2020 7:23 PM, wrote:
On Thu, 2 Jan 2020 17:32:39 -0500, "Mr. Luddite"
wrote:

On 1/2/2020 11:34 AM, wrote:
On Thu, 2 Jan 2020 07:14:10 -0500, "Mr. Luddite"
wrote:

On 1/2/2020 1:31 AM, wrote:
On Wed, 1 Jan 2020 22:50:10 -0500 (EST), Justan Ohlphart
wrote:

Wrote in message:
On Wed, 01 Jan 2020 13:00:28 -0500, John H.
wrote:On Wed, 1 Jan 2020 16:45:16 -0000 (UTC), Bill
wrote:John H.
wrote: On Tue, 31 Dec 2019 21:13:43 -0500, Alex
wrote: Last night...
https://wsvn.com/news/local/several-injured-after-boat-crashes-into-jetty-near-fort-lauderdale/
Cocktails? Not every jetty shows up on a GPS. That happened a few
times in Deale, MD, when folks would follow the GPS to get home.
Midnight and speed. He was not going slow to get that far up the
rocks
a 42? boat.For sure speed. Same thing happens in Deale.
Going fast and taking the line offered by the GPS hasbeen the
problem more than once. Everyone knows I am the real Luddite
here but I fear modernelectronics is taking the place of basic
seamanship and the importanceof local knowledge.

Why do you fear modern ways of navigating? If you should ever
decide to expand your horizons, you might embrace some of the
newer technology available.

Did you read what John wrote? People who trust their GPS blindly, hit
things that are not in the database. The database for the bay here is
pretty much useless anyway unless you just accept "don't go there" as
an answer.
The other issue is, if your electronics fail, do you just drop anchor
and call sea tow, hoping they can triangulate your position on their
radio or something?
I know people who think their Garmin Chart Plotter is all they ever
need. They don't even have a compass and no charts on board ... if
they could read them in the first place.

If that chart plotter craps out they are screwed, particularly at
night.

OTOH I navigate at night using local landmarks (radio towers, condos,
mangrove islands I recognize) and simply knowing where I am and where
I am going.

Greg, your feelings are pretty much exactly how I felt when I first got
into ocean boating. But once I graduated to the larger boats equipped
with GPS, chart plotters and radar I realized that technology had much
to offer over the old ways.

I still had paper charts aboard and obviously a compass but found that
the only time I had to use the charts was to program way-points into
the chart plotter before getting underway in the morning. Never had
to revert to navigating by charts and compass alone.

I saw that the Navy is going back to teaching celestial navigation to
their crews so somebody must think it is important. I suppose someone
pointed out the GPS satellites might only last a couple days in a real
war.
I am not saying these new things are not handy. I am just saying
everyone is depending on technology too much and forgetting basic
skills. It is not just boating. Stand next to a broken cash register
and watch the kid try to make change. It is scary.

The Navy is teaching the basics of celestial navigation at the
Academy only to midshipmen but it's in no way intended to be a serious
navigation tool or method. Part of the reason is a public relations
thing after a Navy ship ran aground, but it had nothing to do with
failure of GPS or other electronic navigation systems.
In other words .... it was operator error.

Today, if the GPS system went down, half of our precision guided
weaponry wouldn't work either ... or be totally inaccurate.

I guess that is why that even the tertiary powers are trying to get
anti satellite capability.

To put your mind at ease: :-)

Military navigation systems (including those aboard ships) are not
necessarily dependent on GPS. The systems developed originally for
nuke subs are now part of the navigation systems aboard surface
ships, missles, etc. The system is called "Inertial Navigation System"
(INS) and can work in concert with GPS or independently without GPS.

Over the years the components and computers used for INS have been
perfected, miniaturized and are incredibly accurate even without
GPS input.

https://aerospace.honeywell.com/en/learn/products/navigation-and-radios/talin-marine-inertial-navigation-system

Yup that is pretty amazing stuff

===

It certainly is. One of the things that really amazes me is
electronic "gyroscopes". All of the older IN systems used mechanical
gyros but nowadays the whole thing is on a microchip that senses
motion by comparing the phase difference of light beams going in
opposite directions.

There was an article in Tech Briefs about that too.
I grew up with a gyro, spun up with air, to some unbelievable speed in
a box the size of a keg cooler. It was a heavy honker that would keep
spinning for a day or so if you lost power.

===

The Naiad stabilizer system on our trawler uses a gyro driven by
hydraulic fluid. It's hidden away inside a fairly beefy housing but
considerably smaller than a beer keg. You can still hear it spinning
for several minutes after shutting the engines down. When the boat
starts to roll, the gyro activates a set of small valves, that in turn
activate a set of much larger valves, similar in concept to a power
relay. The larger valves control hydraulic cylinders which rotate
fins under the boat and counteract the rolling motion. The whole
thing was designed and built by aerospace engineers who have a very
high opinion of their $$$ product. The system works well but
unfortunately it's also a high maintenance item.

http://www.naiad.com/rollstabilizer.asp

KISS! The battleships used Magnetic Amplifiers to control the 16â€ guns.
Forgot how they worked anymore, but they could sense the roll of the ship.

Synchros connected to that big assed gyro I was talking about.
Essentially they use the synchro to tickle the primary of a special
transformer. The input actually came from a Mk1 analog computer that
took the gyro input along with all the other factors in the fire
control problem (relative bearing, speed of the target, speed of your
ship, range, drift, ballistics of that projectile and even the curve
of the earth, more stuff I am forgetting) and outputted the solution
to the mag amp. That MK1 was as big as a "bar" pool table and packed
full of gears and cams, no electronics. I never saw one after I got
out of FT school.