1. Short title This Act may be cited as the Protecting NATO Skies Act of 2019 . 2. Limitation on transfer of F–35 aircraft to Turkey (a) In General Except as provided under subsection (b), no funds may be obligated or expended— (1) to transfer, facilitate the transfer, or authorize the transfer of, an F–35 aircraft to the Republic of Turkey; (2) to transfer intellectual property or technical data necessary for or related to any maintenance or support of the F–35 aircraft; or (3) to construct a storage facility for, or otherwise facilitate the storage in Turkey of, an F–35 aircraft transferred to Turkey. (b) Exception The President may waive the limitation under subsection (a) upon a written certification to Congress that the Government of Turkey does not plan or intend to accept delivery of the S–400 air defense system. (c) Transfer defined In this section, the term transfer includes the physical relocation outside of the continental United States. (d) Applicability The limitation under subsection (a) does not apply to F–35 aircraft operated by the United States Armed Forces. 3. Sense of Congress on purchase by Turkey of S–400 air defense system It is the sense of Congress that, if the Government of Turkey purchases the S–400 air defense system from the Russian Federation— (1) such a purchase would constitute a significant transaction within the meaning of section 231(a) of the Countering Russian Influence in Europe and Eurasia Act of 2017 (title II of Public Law 115–44 ; 22 U.S.C. 9525(a) ); (2) such a purchase would endanger the integrity of the NATO alliance; (3) such a purchase would adversely affect ongoing operations of the United States Armed Forces, including coalition operations in which the United States Armed Forces participate; (4) such a purchase would result in a significant impact to defense cooperation between the United States and Turkey; (5) such a purchase would significantly increase the risk of compromising United States defense systems and operational capabilities