Airplane scattering [ https://en.wikipedia.org/wiki/Airplane_scatter ] (or most often reflection) is observed on radio waves from high frequency to VHF through to microwave and, besides back-scattering, yields momentary propagation up to 800 kilometers (500 miles) even in mountainous terrain. The most common back-scatter applications are air-traffic radar, bistatic forward-scatter guided-missile and airplane-detecting trip-wire radar, and the US space radar.
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Contact opportunities can be predicted based on the precise flight paths of surrounding planes. There exist software solutions for prediction using local (Mode S and ADS-B) or online sources.
ADSBexchange offers a free API for aircraft position data for use by Amateur Radio Operators.
https://rapidapi.com/adsbx/api/aircraftscatter/
If you use this API, then you should contribute to ADSBexchange.com by setting up an ADS-B receiver or adding ADSBexchange.com to your current receiver.
https://www.adsbexchange.com/how-to-feed/
You’ll also receive a Premium Black Enterprise Business Platinum Gold account as a reward.
Example Output for Aircraft Scatter Targets:
{
"lat":55.586243
"lon":-12.092618
"alt_baro":39000
"alt_geom":40625
"track":105.33
"track_rate":0
"gs":495.6
"geom_rate":0
"baro_rate":160
"type":"adsb_icao"
"category":"A5"
"dst":491.367
"dir":304.4
"seen_pos":0.591
"seen":0.6
}
category: emitter category to identify particular aircraft or vehicle classes (values A0 – D7) (2.2.3.2.5.2)
A- = Unspecified powered aircraft
A1 = Light (< 15 500 lbs.)
A2 = Small (15 500 to 75 000 lbs.)
A3 = Large (75 000 to 300 000 lbs.)
A4 = High Vortex Large(aircraft such as B-757)
A5 = Heavy (> 300 000 lbs.)
A6 = High Performance ( > 5 g acceleration and > 400kts)
A7 = Rotorcraft
B- = Unspecified unpowered aircraft or UAV or spacecraft
B1 = Glider/sailplane
B2 = Lighter-than-Air
B3 = Parachutist/Skydiver
B4 = Ultralight/hang-glider/paraglider
B5 = Reserved
B6 = Unmanned Aerial Vehicle
B7 = Space/Trans-atmospheric vehicle
C- = Unspecified ground installation or vehicle
C1 = Surface Vehicle – Emergency Vehicle
C2 = Surface Vehicle – Service Vehicle
C3 = Fixed Ground or Tethered Obstruction
C4 = Cluster Obstacle
C5 = Line Obstacle
C6-C7 = Reserved
D0 = No ADS-B Emitter Category Information
D1-D7 = Reserved