Notwithstanding section 1046 of the National Defense Authorization Act for Fiscal Year 2019 (
[Public Law 115–232],
49 U.S.C. 40101 note), except as provided in subsection (b), the Secretary of a military department may not authorize any manned rotary wing aircraft of the Department of Defense to operate a training mission in a covered airspace unless such aircraft, while being operated, is actively providing warning of the proximity of such aircraft to nearby commercial aircraft in a manner compatible with the traffic alert and collision avoidance system of such commercial aircraft.