Section I: Protection of Civilian Aircraft

[Commentary]


  1. According to Rule 1 (h), “civilian aircraft” means “any aircraft other than military or other State aircraft”. Accordingly, all aircraft not owned or used by a State, serving exclusively non-commercial government functions, qualify as civilian aircraft.

  2. The object and purpose of this Section is to underline that all civilian aircraft, regardless of their nationality, are civilian objects. Accordingly, an attack on civilian aircraft is lawful only in exceptional cases, i.e. if by their location, purpose or use they effectively contribute to the enemy’s military action, and their destruction, capture or neutralization offers — in the circumstances ruling at the time — a definite military advantage, thereby becoming a military objective.

  3. Accordingly, this Manual deviates from the approach underlying the HRAW. According to Art. 33[331] and Art. 34 of the HRAW,[332] enemy civilian aircraft “are liable to be fired upon” if any of the conditions laid down in those provisions are met. The same holds true, under Art. 35 of the HRAW,[333] for neutral aircraft which do not “make the nearest available landing” when “flying within the jurisdiction of a belligerent, and warned of the approach of military aircraft of the opposing belligerent”. In view of the customary character of the definition of military objectives (see Rule 1 (y) and Rule 22), the Group of Experts took the position that those provisions of the HRAW are no longer valid. Hence, civilian aircraft, enemy or neutral, may be attacked only if they meet the requirements of the definition of military objectives. See, respectively, Rule 27 (enemy aircraft other than enemy military aircraft) and Rule 174 (neutral civilian aircraft). For the circumstances in which civilian airliners constitute a military objective, see Rule 63.

  4. Section I is without prejudice to the right of Belligerent Parties to intercept and inspect civilian aircraft and to capture them under the law of prize (see Section U).

  1. Art. 33 of the HRAW: “Belligerent non-military aircraft, whether public or private, flying within the jurisdiction of their own state, are liable to be fired upon unless they make the nearest available landing on the approach of enemy military aircraft.”

  2. Art. 34 of the HRAW: “Belligerent non-military aircraft, whether public or private, are liable to be fired upon, if they fly (1) within the jurisdiction of the enemy, or (2) in the immediate vicinity thereof and outside the jurisdiction of their own state, or (3) in the immediate vicinity of the military operations of the enemy by land or sea.”

  3. Art. 35 of the HRAW: “Neutral aircraft flying within the jurisdiction of a belligerent, and warning of the approach of military aircraft of the opposing belligerent, must make the nearest available landing. Failure to do so exposes them to the risk of being fired upon.”

Safety In Flight

[Commentary]


  1. With the exception of (i) Rule 53 (a); (ii) the second sentence of Rule 54; and (iii) Rule 56, all the Rules laid down in Section I (IV) — rather than reflecting obligations under customary international law — are recommendatory in character. Their object and purpose is to enhance the safety of civilian aircraft in flight.

  2. Section I (IV) applies in its entirety both to enemy civilian aircraft and to neutral civilian aircraft. Unless otherwise indicated, Subsection I (IV) also applies to neutral State aircraft other than military aircraft.

Categories: I: Safety In Flight, Section Headers Tags:

Rule 47

(a)  Civilian aircraft, whether enemy or neutral, are civilian objects and as such are entitled to protection from attack.

[Commentary]

(b) Civilian aircraft can be the object of attack only if they constitute military objectives.

[Commentary]

  1. This Rule emphasizes that, in principle, civilian aircraft are civilian objects that may not be attacked (see Rule 11 and Rule 13).

  2. Civilian aircraft, whether enemy or neutral in character, are not military objectives by nature. In case of doubt as to whether a civilian aircraft is being used for military purposes, it may only be attacked if — based on all the information reasonably available to the commander at the time — there are reasonable grounds to believe that it has become and remains a military objective (see Rule 12 (b)).

  3. For the determination of enemy or neutral character of an aircraft, see respectively Rules 144–146 and Rule 175.

  4. Rule 47 (a), with the exception of the reference to neutral civilian aircraft, applies also in non-international armed conflict.

  1. As to the specific circumstances in which an enemy civilian aircraft may become a military objective, see Rule 27. As to neutral civilian aircraft, see Rule 174.

  2. As to the circumstances in which a civilian airliner (enemy or neutral) constitutes a military objective, see Rule 63. If a civilian airliner constitutes a military objective under Rule 63, it may be attacked only if the conditions laid down in Rule 68 are met.

  3. Rule 47 (b) applies also in non-international armed conflict.

Categories: I: General Rules Tags:

Rule 48

(a) All enemy civilian and State aircraft other than military aircraft may be intercepted, inspected or diverted in accordance with Section U.

[Commentary]

(b) Neutral civilian aircraft may be intercepted, inspected or diverted in accordance with Section U.

[Commentary]

  1. Rule 48 (a) only deals with enemy aircraft, both enemy civilian aircraft and enemy State aircraft other than military aircraft. As to neutral civilian aircraft, see Rule 48 (b).

  2. While enemy civilian aircraft are protected against attack (unless they constitute military objectives, see Rule 47 (b)), they are not protected against other forms of interference by the enemy Belligerent Party. Under customary international law (see Rule 134), enemy civilian aircraft may be captured as prize on the ground or — when flying outside neutral airspace — be intercepted. Moreover, enemy civilian aircraft exempt from capture as prize (e.g., cartel aircraft) may be subjected to inspection if there are reasonable grounds for sus-picion that they are not complying with the conditions rendering them immune from capture (see Rule 67).

  3. As for State aircraft, it is necessary to recall (see Rule 1 (cc)) that they include not only military air-craft, but also law-enforcement and customs aircraft, as well as aircraft employed for other non-commercial government functions. All State aircraft which are not military aircraft come within the scope of Rule 48 (a).

  4. As military objectives by nature (see Rule 22 (a)), enemy military aircraft can be fired upon. A fortiori, enemy military aircraft may be subjected to other belligerent rights, which do not entail their destruction.

  5. Although State aircraft usually enjoy sovereign immunity, this is irrelevant in the relations between Bel-ligerent Parties.

  6. As to inspection of civilian airliners, see Rule 61.

  7. In non-international armed conflicts, only the government will have military aircraft and State aircraft.

  1. Rule 48 (b) is meant to preserve the well-established right of Belligerent Parties of intercepting and inspecting civilian aircraft under Art. 49 of the HRAW,[334] which applies equally to neutral civilian aircraft. For the exercise of those rights, see Section U (II).

  2. It is to be noticed that unlike Rule 48 (a)), Rule 48 (b) does not specifically mention State aircraft. The reason is that neutral State aircraft, in contrast to neutral civilian aircraft, may not be interfered with by Belligerent Parties unless they constitute military objectives (see paragraph 5 of the Commentary on Rule 54 and paragraph 1 of the Commentary on Rule 174). In other words, the belligerent right of interception, inspecting or diverting — which applies to neutral civilian aircraft — does not apply to neutral State aircraft. Such aircraft enjoy sovereign immunity that must be respected by the Belligerent Parties.

  3. Rule 48 (b) does not apply to non-international armed conflict.

  1. Art. 58 (b) of AP/I: “The Parties to the conflict shall, to the maximum extent feasible: … (b) avoid locating military objectives within or near densely populated areas.”

Categories: I: General Rules Tags:

Rule 49

Enemy civilian aircraft are liable to capture as prize in accordance with Rule 134.

[Commentary]

  1. This Rule recognizes the well-established belligerent right to capture enemy civilian aircraft as prize. Enemy civilian aircraft are liable to capture as prize even if they are not engaged in activities rendering them a military objectives (see Rule 27). As to the capture of enemy civilian airliners as prize, see Rule 62.

  2. Capture as prize must be distinguished from capture under the definition of military objectives (see Rule 1 (y) and Rule 22).

  3. For capture as prize of enemy civilian airliners, see Rule 62.

  4. Rule 49 is not applicable in non-international armed conflict, since there is no concept of prize law in non-international armed conflict.

Categories: I: Enemy Civilian Aircraft Tags:

Rule 50

Subject to the specific protection of Sections K and L of this Manual, enemy civilian aircraft are liable to attack if engaged in any of the activities set forth in Rule 27.

[Commentary]

  1. This Rule is meant to emphasize that enemy civilian aircraft are protected from attack (see Rule 47).

  2. Enemy civilian aircraft employed as medical aircraft enjoy specific protection from attack under Section L. This specific protection of attack may be lost if the medical aircraft is engaged in acts harmful to the enemy (see Rule 83). The expression “acts harmful to the enemy” is dealt with in Rule 74, part of Section K.

  3. Civilian airliners may be attacked only if they constitute military objectives under Rule 63 and if the conditions laid down in Rule 68 are fulfilled.

  4. Rule 50 applies also in non-international armed conflict.

Categories: I: Enemy Civilian Aircraft Tags:

Rule 51

Neutral civilian aircraft are liable to capture as prize if engaged in any of the activities enumerated in Rule 140 and if the requirements of Rule 142 are met.

[Commentary]

  1. See the Commentary on Rule 140 and on Rule 142.

  2. Rule 51 does not apply to non-international armed conflict, since there is no neutrality in non-international armed conflict.

Categories: I: Neutral Civilian Aircraft Tags:

Rule 52

Neutral civilian aircraft may not be attacked unless they are engaged in any of the activities enumerated in Rule 174.

[Commentary]

  1. See the Commentary on Rule 174.

  2. Rule 52 does not apply to non-international armed conflict, since there is no neutrality in non-international armed conflict.

Categories: I: Neutral Civilian Aircraft Tags:

Rule 53

(a) In order to enhance their safety whenever in the vicinity of hostilities, civilian aircraft must file with the relevant air traffic control service required flight plans, which will include information as regards, e.g., registration, destination, passengers, cargo, identification codes and modes (including updates en route).

[Commentary]

(b) Civilian aircraft ought not to deviate from a designated air traffic service route or flight plan without air traffic control clearance unless unforeseen conditions arise, e.g., safety or distress, in which case appropriate notification ought to be made immediately.

[Commentary]

  1. This Rule is derived from Para. 76 of the SRM/ACS.[335] The main difference is that filing required flight plans with the relevant air traffic control service is obligatory during armed conflict. Filing such flight plans will enhance the safety of the aircraft by reducing the risk that it will be attacked by mistake.

  2. As to the right of Belligerent Parties to take measures to control civil aviation in the immediate vicinity of hostilities, see Rule 106.

  3. It is particularly important that advance information on the flight plans of civilian aircraft, emergency communication channels and identification modes and codes for civilian aircraft associated with the Secondary Surveillance Radar system (as specified in Annex 10 [“Aeronautical Communications”] to the Chicago Convention) be made available to military forces by the relevant air traffic control service.

  4. Rule 53 (a) applies also in non-international armed conflict.

  1. Para. 76 of SRM/ACS: “Civil aircraft should file the required flight plan with the cognisant Air Traffic Service, complete with information as to registration, destination, passengers, cargo, emergency communication channels, identification modes and codes, updates en route and carry certificates as to registration, airworthiness, passengers and cargo. They should not deviate from a designated Air Traffic Service route or flight plan without Air Traffic Control clearance unless unforeseen conditions arise, e.g., safety or distress, in which case appropriate notification should be made immediately.”

  1. If a civilian aircraft deviates without clearance from designated air traffic service routes or from a flight plan that has been appropriately filed, it runs an increased risk of being fired upon by mistake when it is in the vicinity of hostilities.

  2. Information about any such deviation ought to be provided immediately through the appropriate channels in order to reduce the risk of being fired upon by mistake. This applies also to delays.

  3. Rule 53 (b) applies also in non-international armed conflict.

Categories: I: Safety In Flight Tags:

Rule 54

Civilian aircraft ought to avoid areas of potentially hazardous military operations. In the vicinity of hostilities, civilian aircraft must comply with instructions from the military forces regarding their heading and altitude.

[Commentary]

  1. The first sentence of this Rule is based on Para. 72 of the SRM/ACS.[336] The second sentence is based on the principle contained in Para. 73 of the SRM/ACS.[337]

  2. If a civilian aircraft, flying in the vicinity of hostilities, disregards instructions emanating from the military forces concerning their heading and altitude, it places itself at risk of being fired upon because it may be perceived as a threat.

  3. A civilian aircraft ought to maintain a constant listening watch on frequencies identified for that purpose by relevant NOTAMs (see Rule 55 (a)).

  4. As far as civilian airliners are concerned, see Rule 60.

  5. Rule 54 deals with civilian aircraft. As far as neutral State aircraft are concerned, they enjoy sovereign immunity that must be respected by Belligerent Parties (see Para. 3 of the Commentary on Rule 48 (b) and paragraph 1 of the Commentary on Rule 174). Sovereign immunity, however, does not imply permission for a neutral State aircraft to enter the airspace of a Belligerent Party without consent. Even in international airspace, although clearly entitled to sovereign immunity, neutral State aircraft cannot ignore the hazards of military operations by Belligerent Parties in wartime. Hence, if they do not comply with instructions from the military forces of a Belligerent Party — where military operations are underway — they expose themselves to a greater risk of being attacked.

  6. The second sentence of Rule 54 applies to “the vicinity of hostilities”. When a civilian or other protected aircraft enters an area of potentially hazardous military activity, it must comply with a relevant NOTAM (see Rule 56).

  7. In non-international armed conflict, Rule 54 applies to civilian aircraft and to State aircraft other than military aircraft. Aircraft operated by non-State organized armed groups are civilian aircraft. They are not protected against attack when they are being used for military purposes (see Rule 27).

  8. In non-international armed conflict, a non-State organized armed group cannot issue legally binding instructions to civilian aircraft. An aircraft that fails to comply with instructions from military forces (either government forces or non-State organized armed groups) in an area of military operations is, however, clearly placing itself at greater risk and therefore the commander of the aircraft would be well advised to comply with even those instructions that might come from a non-State organized armed group.

  1. Para. 72 of SRM/ACS: “Civil aircraft should avoid areas of potentially hazardous military activity.”

  2. Para. 73 of SRM/ACS: “In the immediate vicinity of naval operations, civil aircraft shall comply with instructions from the belligerents regarding their heading and altitude.”

Categories: I: Safety In Flight Tags:

Rule 55

Whenever feasible, a Notice to Airmen (NOTAM) ought to be issued by Belligerent Parties, providing information on military operations hazardous to civilian or other protected aircraft and which are taking place in given areas including on the activation of temporary airspace restrictions. A NOTAM ought to include information on the following:

[Commentary]

(a) Frequencies upon which the aircraft ought to maintain a continuous listening watch.

[Commentary]

(b) Continuous operation of civilian weather-avoidance radar and identification modes and codes.

[Commentary]

(c) Altitude, course and speed restrictions.

[Commentary]

(d) Procedures to respond to radio contact by the military forces and to establish two-way communications.

[Commentary]

(e) Possible action by the military forces if the NOTAM is not complied with and if the civilian or other protected aircraft is perceived by those military forces to be a threat.

[Commentary]

  1. This Rule is derived from Para. 75 of the SRM/ACS.[338]

  2. The procedures set forth in Rule 55 are largely based on Section 3 of the ICAO Manual concerning Interception of Civil Aircraft.[339] The construct of Notice to Airmen (NOTAM) is based on ICAO procedures, as established in Annex 15 to the Convention.[340] State practice confirms the use of NOTAMs in recent armed conflicts.

  3. For the purpose of Rule 55, the term “military operations” includes training exercises, practice firings or testing of weapons (see Para. 75.1 of the Commentary on the SRM/ACS).[341]

  4. The issuance of a NOTAM by a Belligerent Party does not relieve it of the obligation to comply with the requirement to take feasible precautions in attack. In this regard, see also Rule 57.

  5. The category of “other protected aircraft” is meant to encompass all aircraft — be they enemy or neutral — which do not constitute military objectives.

  6. In a non-international armed conflict, a State retains responsibility for issuing NOTAMs also with regard to hazardous activities of which it is aware in territory under the control of non-State organized armed groups. The feasibility of providing detailed NOTAMs in such cases may however be impaired by the constraints of the situation.

  7. In a non-international armed conflict, a non-State organized armed group is not in a position to issue formal NOTAMs. Analogous warning procedures ought, however, to be provided when it is within the capabilities of that group to do so, in particular when the latter is able to exercise a measure of physical control over a portion of airspace.

  1. Para. 75 of SRM/ACS: “Belligerent and neutral States should ensure that a Notice to Airmen (NOTAM) is issued providing information on military activities in areas potentially hazardous to civil aircraft, including activation of danger areas or temporary airspace restrictions. This NOTAM should include information on: (a) frequencies upon which the aircraft should maintain a continuous listening watch; (b) continuous operation of civil weather-avoidance radar and identification modes and codes; (c) altitude, course and speed restrictions; (d) procedures to respond to radio contact by the military forces and to establish two-way communications; and (e) possible action by the military forces if the NOTAM is not complied with and the civil aircraft is perceived by those military forces to be a threat.”

  2. Manual concerning Interception of Civil Aircraft (Consolidation of Current ICAO Provisions and Special Recommendations), Second Edition, 1990, Doc 9433-AN/926.

  3. ICAO, Aeronautical Information Services, Annex 15 to the Chicago Convention on International Civil Aviation.

  4. Para. 75.1 of the Commentary on the SRM/ACS: “This paragraph obliges belligerents and neutrals to issue a Notice to Airmen (NOTAM) providing detailed information on military activities in areas potentially hazardous to civil aircraft. These activities could include training exercises, practice firings or testing of weapons in addition to armed conflict at sea. This NOTAM procedure follows the long-standing practice by the military forces of belligerents and neutrals. The NOTAM issued during naval operations in the Adriatic Sea and the Gulf are recent examples. NOTAMs are also prescribed in the ICAO procedures for planning and coordinating military activities potentially hazardous to civil aircraft. Subparagraph (e) warns civil aircraft that if the NOTAMs are not adhered to and the civil aircraft flies in a manner perceived to be threatening by naval forces, such as flying an attack profile, the civil aircraft could be fired upon in self-defence by the naval forces.”

  1. Belligerent Parties are entitled to give instructions to civilian aircraft flying in the vicinity of hostilities (see Rule 54). They may also interrogate an aircraft in order to identify it and, if necessary, to direct warnings to it.

  2. Experience shows that civilian aircraft have been shot down due to misidentification. It is therefore of paramount importance that a constant listening watch be maintained to avoid such incidents.

Civilian identification modes and codes are useful means of identifying civilian aircraft (see Rule 40 (f)). Their correct use is conducive to reducing the risk of civilian aircraft being shot down due to misidentification in the vicinity of military operations.
Flight profile is one of the factors that may indicate that an unidentified aircraft could pose a threat. For this reason, it is important that civilian aircraft behave in a manner that is not perceived as threatening by military forces in the vicinity. Altitude, course and speed restrictions may be given, with a view to avoid any misunderstandings in this respect.
As communication between military forces and civilian aircraft in the vicinity of military operations is essential to ensure the safety of flight, NOTAMs ought to set forth precise procedures by which the military forces and civilian aircraft can communicate with each other. In particular, the radio channel which is being monitored by military forces for this purpose has to be included.
Rule 55 (e) emphasizes that if a NOTAM is not adhered to, and the civilian or other protected aircraft flies in a manner perceived as threatening by military forces — e.g., by flying in an attack profile or by approaching militarily sensitive facilities without permission — it puts its safety in peril (see also Rule 27 (d)).
Categories: I: Safety In Flight Tags:

Rule 56

If a civilian or other protected aircraft enters an area of potentially hazardous military activity, it must comply with a relevant NOTAM.

[Commentary]

  1. This Rule is derived from the first sentence of Para. 77 of the SRM/ACS.[342] However, the Group of Experts inferred from State practice that compliance by a civilian or other protected aircraft with a relevant NOTAM in an area of potentially hazardous military activity is obligatory and not — as presented in the SRM/ACS — optional. See also the second sentence of Rule 54.

  2. As to the meaning of “other protected aircraft”, see paragraph 5 of the Commentary on the chapeau of Rule 55.

  3. As to civilian airliners, see Rule 60.

  4. Although a non-State organized armed group is not in a position to issue formal NOTAMs that are legally binding, an aircraft that fails to comply with instructions from a rebel group clearly places itself at risk.

  1. Para. 77 of SRM/ACS: “If a civil aircraft enters an area of potentially hazardous military activity, it should comply with relevant NOTAMs. Military forces should use all available means to identify and warn the civil aircraft, by using, inter alia, secondary surveillance radar modes and codes, communications, correlation with flight plan information, interception by military aircraft, and, when possible, contacting the appropriate Air Traffic Control facility.”

Categories: I: Safety In Flight Tags:

Rule 57

In the absence of a NOTAM (and, whenever feasible, in case of non-compliance with a NOTAM) military forces concerned ought to use all available means to warn the civilian or other protected aircraft − through radio communication or any other established procedures − before taking any action against it.

[Commentary]

  1. This Rule is based on the second sentence of Para. 77 of the SRM/ACS.[343]

  2. Regardless of the existence of a NOTAM, or even in case of non-compliance with an existing NOTAM, Belligerent Parties remain obligated to take all feasible precautions in attack (see Section G). Moreover, they ought to attempt to establish communications with an incoming aircraft, with a view to warning it of measures about to be taken (attack, inspection, etc.).

  3. The expression “taking any action against it” is meant to encompass not only attacks, but also belligerent measures like interception or diversion. Firing at a civilian or other protected aircraft may only take place when it fulfills the conditions rendering it a military objective. The military forces concerned ought to make every effort to warn an approaching civilian or other protected aircraft before taking any action against at.

  4. Even when no NOTAM or analogous warning has been issued, all feasible precautions must be taken to verify that incoming aircraft are military objectives (see Rule 40), in order to tell them apart from civilian or other protected aircraft that have strayed into the area (see Rule 41).

  5. It must be borne in mind that non-compliance with a NOTAM does not necessarily imply any hostile intent on the part of a civil or other protected aircraft. Non-compliance may have several innocent explanations such as language difficulties or navigational error. This is the reason why warnings to an incoming civilian or other protected aircraft have to be issued prior to taking action against it.

  6. The expression “military forces concerned” was preferred by the Group of Experts over the alternative phrase “military forces on the spot”, in order to convey the notion that the available means may also be used by forces that are at some distance from the scene of action.

  7. As to the meaning of “other protected aircraft”, see paragraph 5 of the Commentary on the chapeau to Rule 55.

  8. Rule 57 applies also in non-international armed conflict.

  1. Para. 77 of SRM/ACS, see fn. 342.

Categories: I: Safety In Flight Tags: