Interesting GPS observation

Old 04-16-2007, 01:28 PM
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Default Interesting GPS observation

I was bringing the charter boat back from the boat yard last Thursday. I took my hand held along with to compare the trip measurables: trip time, top speed, yadda yadda yadda...

The trip to the yard took 2 hours twenty minutes with a top speed of 18.5 knots. Not to bad considering the length of time the boat had sat. I did dive under it two weeks prior and got all of the barnacles off the running gear so I could at least get up on plane.

So, trip back with fresh paint and super clean props, shafts, rudders....Almost indentical time, however, my top speed was recorded as 160 knots... ..WTF?

About 3/4 of the way back to the island, a military propellor driven plane had passed over head and the lil' Garmin GPSMap 76 went squirrelly. My track changed about 180 degrees and slowly crept back to normal. I didn't pay much attention to the speed, but, bearing was still the same. When I got to the dock and was checking it was really surprising to find what a good bottom job will do for your top end.

One time in the summer of 1999 or 2000, I had a hand held Magellan blank out while some jet fighters were mock dog fighting over the gulf overhead.

So, is it the hard core aviation radar or are they jamming the sats around the war birds? I think it is the later.
capt_dalton is offline  
Old 04-16-2007, 02:34 PM
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Default Re: Interesting GPS observation

Looks like nobody on here knows, or if they DO know they cant write about it. But I would bet with you.
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Old 04-16-2007, 03:54 PM
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Default RE: Interesting GPS observation

That would be G4 classified.

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Old 04-16-2007, 07:25 PM
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Default Re: Interesting GPS observation

Thta's called the Other 5%, 5% of the time that the system can not control, it will never be 100%. Could be many reasons but if it was an actual GPS jammer then you wouldn't have had any signals. Speed would have been ziltch. Sounds more like typical RFI and signal interference.
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Old 04-16-2007, 09:09 PM
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Top speed of 160 knots???? You didnt run any Govenors off the road, did you?

Uh, what brand bottom paint is that, anyway?
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