; and (2) running scenarios for each ATCT involving differing levels of air traffic volume and varying complexities, including, aircraft emergencies, rapidly changing weather, issuance of safety alerts, special air traffic procedures for events of national or international significance, and recovering from unforeseen events or losses of separation. (d) Mobile TSS Not later than 4 years after the date of enactment of this Act, the Administrator shall acquire and implement mobile TSS at each ATCT that is without an existing, permanent TSS so that the mobile TSS is capable of, at a minimum, the capabilities described in paragraphs (1) and (2) of subsection (c). (e) Collaboration In carrying out this section, the Administrator may collaborate with the exclusive bargaining representative of air traffic controllers certified under section 7111 of title 5, United States Code. 416. Air traffic controller instructor recruitment, hiring, and retention (a) In general No later than 270 days after the date of enactment of this Act, the Administrator shall initiate a study examining the recruitment, hiring, and retention of air traffic controller instructors and the projected number of instructors needed to maintain the safety of the national airspace system over a 5-year period beginning with fiscal year 2025. (b) Contents The Administrator shall include in the study required under subsection (a) the following: (1) An examination of projected instructor staffing targets, including the number of on-the-job instructors needed for the instruction and training of Certified Professional Controllers (in this section referred to as CPCs ) in training. (2) An analysis on whether involving additional retired CPCs as instructors, including for classroom training, would produce improvements in air traffic controller instruction and training. (3) Recommendations on how and where to utilize retired CPCs. (4) The effect on the ability of active CPCs to carry out on-the-job duties, other than instruction, and any related efficiencies if