Transitional measures
Article 4
1. Providers of ATM/ANS shall take the necessary measures to ensure a smooth and safe transition to the provision of their services using performance-based navigation in accordance with Article 3. Those measures shall include the establishment and implementation of a transition plan. Providers of ATM/ANS shall keep their transition plan up-to-date. The transition plan shall be consistent with the European ATM Master Plan and the common projects referred to in Article 15a of Regulation (EC) No 550/2004 of the European Parliament and of the Council ( 12 ) . 2. Providers of ATM/ANS shall consult all of the following parties on the draft transition plan and the draft of any significant updates thereof and take account of their views where appropriate: (a) aerodrome operators, airspace users and representative organisations of such airspace users affected by the provision of their services; (b) the Network Manager referred to in Article 3(1) of Regulation (EU) No 677/2011; (c) providers of ATM/ANS that provide their services in adjacent airspace blocks. 3. After having carried out the consultation referred to in paragraph 2, providers of ATM/ANS shall submit the results of the consultation, as well as the draft transition plan, or the draft significant update thereof, for approval to the competent authority responsible for the airspace concerned. That competent authority shall verify whether the draft transition plan, or the draft significant update thereof, complies with the requirements of this Regulation and in particular whether it takes account of the views of airspace users where appropriate, including those operating State aircraft. Member State of the competent authority may provide that such verification shall be carried out in coordination with other relevant authorities of the Member State concerned. That competent authority shall inform the providers of ATM/ANS of the outcome of that verification without undue delay. Providers of ATM/ANS shall not establish or implement the transition plan, or the significant update thereof, before having been informed by that competent authority that it has approved the draft transition plan or draft significant update thereof.