; and (ii) in paragraph (5)(A)(i) by striking or chapter 451, and inserting chapter 451, chapter 455, ; (B) in subsection (d)(2) by inserting chapter 455, after chapter 451, ; and (C) in subsection (f)(1)(A)(i) by striking or chapter 451 and inserting chapter 451, or chapter 455 . (3) Clerical amendment The analysis for subtitle VII of title 49, United States Code, is amended by inserting after the item relating to chapter 453 the following: 455. Unmanned aircraft systems 45501 . 433. Unmanned aircraft test ranges (a) Extension of program Section 332(c)(1) of the FAA Modernization and Reform Act of 2012 ( 49 U.S.C. 40101 note) is amended by striking September 30, 2019 and inserting the date that is 6 years after the date of enactment of the 21st Century AIRR Act . (b) Sense-and-Avoid and beyond line of sight systems at test ranges (1) In general To the extent consistent with aviation safety, the Administrator of the Federal Aviation Administration shall permit and encourage flights of unmanned aircraft equipped with sense-and-avoid and beyond line of sight systems at the 6 test ranges designated under section 332(c) of the FAA Modernization and Reform Act of 2012. (2) Waivers In carrying out paragraph (1), the Administrator may waive the requirements of section 44711 of title 49, United States Code, including related regulations, to the extent consistent with aviation safety. (c) Test range defined In this section, the term test range means a defined geographic area where research and development are conducted. 434. Sense of Congress regarding unmanned aircraft safety It is the sense of Congress that— (1) the unauthorized operation of unmanned aircraft near airports presents a serious hazard to aviation safety; (2) a collision between an unmanned aircraft and a conventional aircraft in flight could jeopardize the safety of persons aboard the aircraft and on the ground