I thought of this while observing an airplane flying high overhead. I wondered what was the origin and destination of the flight. It occurred to me, the path could probably be calculated if I had 3 carefully measured observations of its position in the sky (angular altitude & azimuth), plus my latitude & longitude, assuming the plane was traveling in a straight line (strictly speaking, a great circle) at a constant altitude. Adding the exact time of the observations, it would also be possible to calculate the speed. By matching the data to a worldwide map of airports and schedule of flights, you could even make a reasonable guess of the exact flight number (assuming it’s a commercial flight).

All we’d need would be an instrument to make the observations—something like a surveyor’s transit—and a device or a web site to do the calculations and matching.

Well, it sounds more interesting to me than looking at stars with a telescope. Do I have trainspotter tendencies?
-- Jim Bob of Merriam Park, Jul 27 2009

Vessel Tracker http://www.vesseltr...nfrancisco/Map.html
Like this, for planes? [csea, Jul 27 2009]

Look up http://www.flightaware.com/
and it will even e-mail you. [lurch, Jul 27 2009]

vessel finder https://ship-tracking.net/vesselfinder/
Track any ship or vessel anywhere in the world! [vessel finder, Jun 18 2020, last modified Jul 28 2020]

Tracker https://www.flightr....com/38.68,-95.62/7
I'm leaving, on a jet plane... [whatrock, Jun 18 2020]

A similar app. exists for Marine traffic in the SF Bay area. [link]
-- csea, Jul 27 2009


The flightaware info is delayed 5 minutes, so when you see something, you have to adjust accordingly to find it in the data.
-- lurch, Jul 27 2009


Airliners follow "airways" in controlled airspace. So if you've got the half-million scale ICAO sheet for your area, you can work out which airway it's in, and where it will turn; but not where it's going, or come from - a bit like trying to infer the start and end points of a car or train journey from observing them at one intermediate point. The horizon's about 50km away and airways are a lot longer than that.

// Do I have trainspotter tendencies? //

Yes; but it's not something to be ashamed of.
-- 8th of 7, Jul 27 2009


An iPhone or other smartphone device has accelerometers that allow device orientation to be determined, a very precise clock driven by a centralized atomic clock, a camera of sufficient resolution, a GPS, connectivity and some processing power. Given these ingredients, it might be possible to identify a specific flight by taking and analyzing a photo of the airplane as it passes over.

You see an airliner and take a photo with the phone. First up after the photo is taken is an image recognition routine and an aircraft database to distill which end of the aircraft is the nose and how the aircraft is oriented. The GPS and, if needed, some radio tower triangulation, determines the location of the phone. Using the accelerometers and the clock, you determine the orientation of the phone, with respect to gravity, at the moment the photo is taken. Using connectivity, you query flightaware.com or a similar online DB to get what flights are going what way and when for your location and report the likeliest flight number back to the user.

Maybe you could even get the specific aircraft and present a history of the plane including incidents, number of cycles, ownership, equipment, engine type and so on.
-- gen1000, Aug 06 2009



random, halfbakery