Hi everybody, I have been hearing that the EASA requirement to start commercial schedule flights in European countries (Germany, France) need pair concept of aircraft i.e. two B777, two A330 etc. Is it a mandatory EASA/JAAR regulation or only advice? If it is a mandatory rule where can I find the information. Thank you for the help and information.

Capt. K.B. Limbu
www.kblimbu.com.np