Règle correspondante
Practice Relating to Rule 29. Medical Transports
Section B. Respect for and protection of medical aircraft
France’s LOAC Summary Note (1992) states: “Medical transports must not be used to collect military information.” 
France, Fiche de Synthèse sur les Règles Applicables dans les Conflits Armés, Note No. 432/DEF/EMA/OL.2/NP, Général de Corps d’Armée Voinot (pour l’Amiral Lanxade, Chef d’Etat-major des Armées), 1992, § 2.3.
The instructions given to the French armed forces for the conduct of Opération Mistral, simulating a military operation under the right of self-defence or a mandate of the UN Security Council, refer to Articles 25 and 27 of the 1977 Additional Protocol I. 
France, Etat-major de la Force d’Action Rapide, Ordres pour l’Opération Mistral, 1995, Section 6, § 62.
Upon ratification of the 1977 Additional Protocol I, France stated:
Given the practical need to use non-dedicated aircraft for medical evacuation missions, the Government of the Republic of France does not interpret paragraph 2 of Article 28 as precluding the presence on board of communication equipment and encryption material or the use thereof solely to facilitate navigation, identification or communication in support of a medical transportation mission as defined in Article 8. 
France, Reservations and declarations made upon ratification of the 1977 Additional Protocol I, 11 April 2001, § 5.