This week's issue (April 22- May 5) of
Aviation Week and Space Technology (aka Aviation Leak and Space Mythology) has an article on Counter UAS (CUAS). The second paragraph sums up the problems pretty well:
"
In the U.S. and many other countries, shooting down, disabling or taking control of drones is illegal. There is no liability framework for such operations, no broadly reliable way to detect and identify drones and drone users and the U.S. has yet to figure out exactly who will have authority to execute CUAS operations."
Later in the article it notes that in July, 2018 the FAA sent airports a CUAS guidance letter. The letter repeated part of a 2016 letter:
"
It is important that federally obligated airports understand that the FAA has not authorized any UAS detection or countermeasure assessments other than those participating in the
FAA's UAS detection program...and airports allowing such evaluations could be in violation of their grant assurances."
The article also notes that in the US, radio transmitters, including jammers have to be licensed by the FCC, and that no licenses have been issued for CUAS jamming systems. The article doesn't point out that US government radio systems aren't licensed or regulated by the FCC, but are coordinated by the National Telecommunications and Information Administration (NTIA).
It does mention that the FAA Reauthorization Act of 2018, the same one that made changes to Part 101 (336) and Part 107, allows the Departments of Justice and Transportation to basically do whatever they need to do to mitigate threats from an unmanned aircraft. That's contained in "Division H - Preventing Emerging Threats" of the Act, and can be read here (search for "Division H":
https://www.congress.gov/bill/115th...02/text#toc-H11CC147789714B1FA95400F38BA66A4A
The rest of the article has interviews with executives from companies that provide CUAS products and services. They admit that no one system is ideal, and that probably the only surefire defense is a kinetic system - the fancy way of saying shooting them down. One of the execs points out that if a CUAS system takes control of a vehicle, liability potentially passes to the operator of that system.
Interesting read without a lot of details.