Related Rule
Australia
Practice Relating to Rule 48. Attacks against Persons Parachuting from an Aircraft in Distress
Australia’s Commanders’ Guide (1994) provides:
Parachutists are defined as those who abandon a disabled aircraft. Parachutists are not legitimate military targets … It is appreciated that it may be difficult to distinguish a parachutist from a paratrooper, especially while in the air. 
Australia, Law of Armed Conflict, Commanders’ Guide, Australian Defence Force Publication, Operations Series, ADFP 37 Supplement 1 – Interim Edition, 7 March 1994, § 412.
The Guide also states:
Aircrew who have baled out of a damaged aircraft are to be considered as hors de combat and should not be attacked during their descent. However, should the parachutist land in enemy territory he must be given an opportunity to surrender before being made the object of an attack unless it is apparent that he is engaged in a hostile act. If he lands within territory occupied by his own national authority, he is liable to be attacked by the enemy, like any other combatant, unless wounded and, therefore, protected by LOAC.
The ban on shooting down those descending by parachute does not extend to the dropping of agents or paratroops. 
Australia, Law of Armed Conflict, Commanders’ Guide, Australian Defence Force Publication, Operations Series, ADFP 37 Supplement 1 – Interim Edition, 7 March 1994, §§ 964 and 965 (land warfare); see also §§ 412, 621, 705 and 1033 (air warfare).
Australia’s Defence Force Manual (1994) states:
Aircrew descending by parachute from a disabled aircraft are immune from attack. If such personnel land in enemy territory they must be given an opportunity to surrender before being made the object of an attack, unless it is apparent that they are engaging in some hostile act. 
Australia, Manual on Law of Armed Conflict, Australian Defence Force Publication, Operations Series, ADFP 37 – Interim Edition, 1994, § 847; see also § 708.
The manual adds:
849. If the crew of a disabled aircraft lands by parachute in territory occupied by their own forces or under the control of their own national authority, they may be attacked in the same way as any other combatant, unless wounded, in which case they are protected. If in a raft or similar craft at sea after parachuting, they are to be treated as if shipwrecked and may not be attacked.
850. Paratroopers and other airborne troops may be attacked, even during their descent. If the carrying aircraft has been disabled it may be difficult to distinguish between members of the crew abandoning such aircraft who are immune from attack, and the airborne troops who are not so protected. 
Australia, Manual on Law of Armed Conflict, Australian Defence Force Publication, Operations Series, ADFP 37 – Interim Edition, 1994, §§ 849–850.
Australia’s LOAC Manual (2006) states:
8.43 … [A]ircraft may not fire upon shipwrecked personnel, including those who may have parachuted into the sea or otherwise come from downed aircraft, so long as the personnel have not been picked up. These rules do not alter the fact that any attempt by the enemy to recover downed crew may be opposed.
8.51 Aircrew descending by parachute from a disabled aircraft are immune from attack. If such personnel land in enemy territory they must be given an opportunity to surrender before being made the object of an attack, unless it is apparent that they are engaging in some hostile act.
8.52 If personnel from a disabled aircraft do not surrender on being called upon to do so, they may be attacked in the same way as any other combatant. …
8.53 If the crew of a disabled aircraft lands by parachute in territory occupied by their own forces or under the control of their own national authority, they may be attacked in the same way as any other combatant, unless wounded, in which case they are protected. If in a raft or similar craft at sea after parachuting, they are to be treated as if shipwrecked and may not be attacked.
8.54 Paratroopers and other airborne troops may be attacked, even during their descent. If the carrying aircraft has been disabled it may be difficult to distinguish between members of the crew abandoning such aircraft who are immune from attack, and the airborne troops who are not so protected. 
Australia, The Manual of the Law of Armed Conflict, Australian Defence Doctrine Publication 06.4, Australian Defence Headquarters, 11 May 2006, §§ 8.43 and 8.51–8.54; see also § 7.9.
The LOAC Manual (2006) replaces both the Defence Force Manual (1994) and the Commanders’ Guide (1994).