Rule 48. Attacks against Persons Parachuting from an Aircraft in Distress
Rule 48. Making persons parachuting from an aircraft in distress the object of attack during their descent is prohibited.
Summary
State practice establishes this rule as a norm of customary international law applicable in both international and non-international armed conflicts.
International armed conflicts
The prohibition on attacking persons parachuting from an aircraft in distress during their descent was already recognized in the Hague Rules of Air Warfare, drafted by a commission of jurists in 1922–1923,[1]  and was considered to reflect a rule of customary international law.[2]  As such, it was codified in Article 42 of Additional Protocol I.[3]  Article 42 was not, however, adopted by consensus because some States felt that persons landing in their own territory could not be considered hors de combat. But this view was defeated and in the end the issue was resolved in favour of considering such persons as hors de combat during their descent, wherever they might land.[4]  A parallel can be drawn here with the shipwrecked, who are considered to be hors de combat (in both international and non-international armed conflicts) even though they may swim ashore or be collected by a friendly ship and resume fighting. In this respect, it is interesting to note that persons bailing out of an aircraft in distress have been called “shipwrecked in the air”. This rule is now generally accepted and, as a result, no reservations have been made to Article 42.
In addition, numerous military manuals prohibit attacks against persons parachuting from an aircraft in distress.[5]  These include manuals of States not, or not at the time, party to Additional Protocol I.[6]  This rule is also supported by official statements, such as military communiqués, and reported practice.[7] 
Non-international armed conflicts
The prohibition on attacking persons parachuting from an aircraft in distress is also applicable in non-international armed conflicts on the basis of common Article 3 of the Geneva Conventions, which protects persons placed hors de combat by “any” cause.[8]  During the negotiation of the elements of war crimes against common Article 3 in the framework of the Statute of the International Criminal Court, the drafters understood that the term hors de combat should not be interpreted in a narrow sense, and made reference to Article 42 of Additional Protocol I, in addition to the examples contained in common Article 3.[9]  This rule is contained in several military manuals which are applicable in or have been applied in non-international armed conflicts.[10] 
As explained above, the main concern about considering persons parachuting from an aircraft in distress as hors de combat during their descent was that they might land in their own territory. The international community has resolved this issue in favour of considering such persons as hors de combat during the time they are in the air, wherever they may land afterwards. Hence, there is no practical impediment to applying this rule in non-international armed conflicts and no opinion has been expressed that it should be so limited.
Interpretation
Practice indicates that upon reaching the ground, persons parachuting from an aircraft in distress are to be given an opportunity to surrender, unless it is apparent that they are engaging in a hostile act. This principle is set forth in Additional Protocol I.[11]  It is also contained in many military manuals.[12]  The Commentary on the Additional Protocols explains that this rule establishes a presumption that, until they have made the opposite intention known, downed aircrew intend to surrender.[13]  The US Air Force Pamphlet specifies, however, that combatants parachuting from an aircraft in distress and landing uninjured behind their own lines may be attacked, since an offer to surrender would be impossible to accept.[14]  This is in conformity with the explanation provided concerning the definition of surrender (see commentary to Rule 47).
This rule is to the benefit of all crew of an aircraft in distress, civilians and combatants alike, but does not apply to troops that are airborne as part of a military operation and that are not bailing out in distress.[15] 

[1] Hague Rules of Air Warfare, Article 20 (cited in Vol. II, Ch. 15, § 423).
[2] See United States, Annotated Supplement to the Naval Handbook (ibid., § 470).
[3] Additional Protocol I, Article 42 (ibid., § 421); see Yves Sandoz, Christophe Swinarski, Bruno Zimmermann (eds.), Commentary on the Additional Protocols (ibid., § 481); Michael Bothe, Karl Joseph Partsch, Waldemar A. Solf (eds.), New Rules for Victims of Armed Conflicts (ibid., § 485).
[4] The military and humanitarian reasons for which this decision was taken are explained in Yves Sandoz, Christophe Swinarski, Bruno Zimmermann (eds.), Commentary on the Additional Protocols, ICRC, Geneva, 1987, § 1642.
[5] See, e.g., the military manuals of Argentina (cited in Vol. II, Ch. 15, §§ 424–425), Australia (ibid., §§ 426–427), Belgium (ibid., §§ 428–429), Benin (ibid., § 430), Burkina Faso (ibid., § 431), Cameroon (ibid., §§ 432–433), Canada (ibid., § 434), Congo (ibid., § 435), Croatia (ibid., § 436), Dominican Republic (ibid., § 437), Ecuador (ibid., § 438), France (ibid., §§ 439–441), Germany (ibid., § 442), Indonesia (ibid., § 443), Israel (ibid., § 444), Italy (ibid., §§ 446–447), Kenya (ibid., § 448), Lebanon (ibid., § 449), Madagascar (ibid., § 450), Mali (ibid., § 451), Morocco (ibid., § 452), Netherlands (ibid., § 453), New Zealand (ibid., § 454), Nigeria (ibid., § 455), Russian Federation (ibid., § 456), Senegal (ibid., § 457), South Africa (ibid., § 458), Spain (ibid., § 459), Sweden (ibid., § 460), Switzerland (ibid., § 461), Togo (ibid., § 462), United Kingdom (ibid., §§ 463–464), United States (ibid., §§ 465–470) and Yugoslavia (ibid., § 471).
[6] See the military manuals of Cameroon (ibid., § 432), France (ibid., § 439), Indonesia (ibid., § 443), Israel (ibid., § 444), Kenya (ibid., § 448), Lebanon (ibid., § 449), Mali (ibid., § 451), Morocco (ibid., § 452), United Kingdom (ibid., §§ 463–464) and United States (ibid., §§ 465–470).
[7] See, e.g., Egypt, Military Communiqués Nos. 34 and 46 (ibid., § 476); Islamic Republic of Iran, Military Communiqué of 29 September 1980 (ibid., § 477); Iraq, Military Communiqués Nos. 541, 683, 996 and 1383 and Reply by the Ministry of Defence to a questionnaire (ibid., § 478); United States, Remarks of the Deputy Legal Adviser of the Department of State (ibid., § 480) and Letter from the Department of the Army to the legal adviser of the US Army forces deployed in the Gulf region (ibid., § 481); reported practice of Pakistan (ibid., § 479).
[8] Geneva Conventions, common Article 3 (cited in Vol. II, Ch. 32, § 1).
[9] Knut Dörmann, Elements of War Crimes under the Rome Statute of the International Criminal Court: Sources and Commentary, Cambridge University Press, 2003, p. 389.
[10] See, e.g., the military manuals of Australia (cited in Vol. II, Ch. 15, § 426), Benin (ibid., § 430), Croatia (ibid., § 436), Ecuador (ibid., § 438), Germany (ibid., § 442), Italy (ibid., §§ 446–447), Kenya (ibid., § 448), Lebanon (ibid., § 449), Madagascar (ibid., § 450), South Africa (ibid., § 458), Togo (ibid., § 462) and Yugoslavia (ibid., § 471).
[11] Additional Protocol I, Article 42 (ibid., § 421).
[12] See, e.g., the military manuals of Argentina (ibid., § 425), Australia (ibid., §§ 426–427), Belgium (ibid., §§ 428–429), Cameroon (ibid., § 432), Canada (ibid., § 434), Dominican Republic (ibid., § 437), Ecuador (ibid., § 438), France (ibid., § 441), Indonesia (ibid., § 443), Kenya (ibid., § 448), Netherlands (ibid., § 453), New Zealand (ibid., § 454), Spain (ibid., § 459), Sweden (ibid., § 460), Switzerland (ibid., § 461) and United States (ibid., §§ 466–467 and 469–470).
[13] Yves Sandoz, Christophe Swinarski, Bruno Zimmermann (eds.), Commentary on the Additional Protocols (ibid., § 486).
[14] United States, Air Force Pamphlet (ibid., § 466).
[15] See, e.g., the military manuals of Argentina (ibid., §§ 424–425), Australia (ibid., §§ 426–427), Belgium (ibid., §§ 428–429), Benin (ibid., § 430), Burkina Faso (ibid., § 431), Cameroon (ibid., §§ 432–433), Canada (ibid., § 434), Congo (ibid., § 435), Dominican Republic (ibid., § 436), Ecuador (ibid., § 438), France (ibid., §§ 439–441), Germany (ibid., § 442), Indonesia (ibid., § 443), Israel (ibid., §§ 444–445), Italy (ibid., § 446), Kenya (ibid., § 448), Lebanon (ibid., § 449), Mali (ibid., § 451), Morocco (ibid., § 452), Netherlands (ibid., § 453), New Zealand (ibid., § 454), Nigeria (ibid., § 455), Russian Federation (ibid., § 456), Senegal (ibid., § 457), South Africa (ibid., § 458), Spain (ibid., § 459), Sweden (ibid., § 460), Switzerland (ibid., § 461), Togo (ibid., § 462), United Kingdom (ibid., §§ 463–464), United States (ibid., §§ 465–467 and 469) and Yugoslavia (ibid., § 471).