I would be grateful for any help.

What exactly do I have to change so that helis take damage when they fly into a tree, for example?
But players should not be able to damage other players' helis.

    {
      "name": "default",
      "enabled": true,
      "defaultAllowDamage": false,
      "flags": "AuthorizedDamage, HumanNPCDamage, LockedBoxesImmortal, TwigDamage, LockedDoorsImmortal, PlayerSamSitesIgnorePlayers, TrapsIgnorePlayers, TurretsIgnorePlayers, AdminsHurtSleepers, SelfDamage",
      "rules": [
        "anything can hurt dispensers",
        "anything can hurt resources",
        "anything can hurt barricades",
        "anything can hurt traps",
        "anything can hurt heli",
        "anything can hurt npcs",
        "anything can hurt players",
        "nothing can hurt ch47",
        "anything can hurt cars",
        "nothing can hurt mini",
        "anything can hurt ridablehorses",
        "cars cannot hurt anything",
        "mini cannot hurt anything",
        "scrapheli cannot hurt anything",
        "players can hurt pinata",
        "players cannot hurt players",
        "players cannot hurt traps",
        "guards cannot hurt players",
        "fire can hurt players",
        "samsite can hurt mini",
        "samsite can hurt scrapheli",
        "traps cannot hurt players",
        "highwalls cannot hurt players",
        "barricades cannot hurt players",
        "mini cannot hurt mini",
        "npcs can hurt players",
        "junkyard cannot hurt anything",
        "junkyard can hurt cars",
        "ch47 can hurt mini",
        "ch47 can hurt scrapheli",
        "mlrs can hurt anything"
      ]
    }

heya.

"What exactly do I have to change so that helis take damage when they fly into a tree, for example?"
heli takes damage from everything, and will only use rules for players or other patrol helicopters when taking damage. if heli does damage to something then that requires heli flags.

"But players should not be able to damage other players' helis."
truepve does not handle that. loot defender can, but it's not perfect.

Thank you for your feedback.
I think I misunderstood you or expressed myself incorrectly in the translation. I will ask again in a different way.
Minicopters, Scrapheli and Attackheli do not take damage if they fly into something or players crash with them.
But I would like this to happen.

mini can hurt mini
scrapheli can hurt scrapheli

I don't know about attack heli.