Соответствующая норма
United Kingdom of Great Britain and Northern Ireland
Practice Relating to Rule 7. The Principle of Distinction between Civilian Objects and Military Objectives
Section E. Attacks against civilian means of transportation
The UK LOAC Manual (2004) states: “The following classes of enemy aircraft are exempt from attack: … b. aircraft granted safe conduct by agreement between the parties to the conflict; and c. civil airliners.” 
United Kingdom, The Manual of the Law of Armed Conflict, Ministry of Defence, 1 July 2004, § 12.28.