Accuracy of plane finder


New Member
Hi all,

I would like some assistance in using planefinder please.

1: Accuracy. I was on a flight the other day, I knew the exact approach path into Sydney Sustralia yet plane finder showed an incorrect path, off by about 10km. Two other ADSB tracking sites showed the correct path. Why?
2: When I try to look at historical data, the website reverts to France (I am in Australia) so I have to recenter the map, even though I started in the correct place.
3: When I try to set the historical time, it reverts to 1745.

I'm providing some ADS-B data from the Boston area. The area south of Logan airport is blocked from my location. (Hills).
When planes are on their final approach from the south, and drop down to under 800 feet, my antenna can't see them..

I'll see a plane coming in that southern approach suddenly stop, I know I've lost it's signal..
But doesn't stop my iPhone display.

On my Planefinder iPhone app (free version), the plane just keeps on going. And going.
It flies right over the airport and heads north for a while, then disappears..

However, it actually landed. It didn't really just buzz the airport. But, the PlaneFinder aircraft prediction software,
decided to keep showing the plane on it's last known speed, heading and altitude.

After loss-of-signal, It didn't have the data it needed. When it timed-out, it erased the plane off the Iphone display..
We need a receiver on the South shore of Boston.

So, Accuracy, or continuous accuracy, depends on the amount of receivers in your area.
If there are a lot of ground stations providing data, and the plane is always within line-of-sight
of at least one of the stations, continuous accuracy will be excellent.

In this screensaves, you can see the plane stops moving on my display (1375 ft @ 203 mph), but keeps the same heading, speed & altitude.. Seemingly passing right over the airport..
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