Rule 47. Attacking persons who are recognized as hors de combat is prohibited. A person hors de combat is:
(a) anyone who is in the power of an adverse party;
(b) anyone who is defenceless because of unconsciousness, shipwreck, wounds or sickness; or
(c) anyone who clearly expresses an intention to surrender;
provided he or she abstains from any hostile act and does not attempt to escape
There’s regularly uploaded footage of clearly surrendering soldiers directed towards a safe zone to give up. Propaganda is propaganda, but it happens more often than we might think.
I wonder if some "Surrendering to a Drone" protocol couldn't be codified under the Geneva Convention EG "Visibly disassemble your gun, throw the bits in several directions" etc.
Rule 3. All members of the armed forces of a party to the conflict are combatants, except medical and religious personnel.
https://ihl-databases.icrc.org/en/customary-ihl/v1/rule3
Rule 47. Attacking persons who are recognized as hors de combat is prohibited. A person hors de combat is: (a) anyone who is in the power of an adverse party; (b) anyone who is defenceless because of unconsciousness, shipwreck, wounds or sickness; or (c) anyone who clearly expresses an intention to surrender; provided he or she abstains from any hostile act and does not attempt to escape
https://ihl-databases.icrc.org/en/customary-ihl/v1/rule47
A surprise drone attack on any Russian combatant that isn't a medic or chaplain is "lawful", even if they aren't holding a weapon at the time.