One popular question that we encounter regularly is whether air forces around the world use ADS-B on their aircraft. After all aircraft transponders are originally a military invention to identify friends from foes and the well-known benefits of ADS-B equipage in civil airspaces also apply to military aircraft. On the other hand, both cost and security reasons have been cited for not wanting to use ADS-B on sensitive aircraft. So, what is the deal right now, less than two years before the 2020 equipage deadline in Europe and the US?
In short, yes, air forces do use ADS-B, at least partially, but there are massive usage differences between countries.
This is from our recent paper at the 36th Digital Avionics Systems Conference . We collected ADS-B and Mode A/C/S data from over 6000 aircraft operated by militaries all over the world (with a strong focus on Europe/the US) using the The OpenSky Network. The key plot on how air forces around the world use ADS-B is the following:
As we can see, the military ADS-B adoption rate varies between around 10% in Israel to 90% in Saudi Arabia.
The same, a bit more detailed, for some selected countries:
Here, you see the share of aircraft which use Mode S only or additional technologies such as ACAS, or ADS-B, or all three.
Finally, we know that military aircraft can switch off ADS-B when they choose to. This happens regularly, some only really seem to use it en-route in “safe” airspaces but switch it off for their approach to make it ever so slightly harder to see where they land (well, not really but that’s a story for another blog post). But for that, and other information such as ADS-B equipage per aircraft type, you can read the full paper.
 Matthias Schäfer, Martin Strohmeier, Matthew Smith, Markus Fuchs, Vincent Lenders, Marc Liechti and Ivan Martinovic. OpenSky Report 2017: Mode S and ADS-B Usage of Military and other State Aircraft. In IEEE/AIAA 36th Digital Avionics Systems Conference. September 2017.
You can find all our publications on Aviation Security on our Publications page.