It's too easy to accidentally dismount from flyers, quickly falling to your death.

Features

To dismount from flyer dinos double tap the Use key or long press the Use key.
Config to disable long press option.
Config to enable protection for all dinos, not just flyers.
Death prevention if player gets disconnected while flying.
Access the personal radial wheel while mounted to add/remove dino types to the blacklist.
When seatbelt is active on flyers that are flying and stamina falls below 25%, you get a warning you're low on stamina.
Enables backwards walking on all dinos, after mounting them.
Client options, including long hold dismount, low stamina warnings & which dinos are enabled, are accessed via the player radial wheel.
Support for Mod Settings Panel: https://www.curseforge.com/ark-survival-ascended/mods/mod-admin-panel

Server Configs:

[FlyerSeatbelts]
ForceEnableMountedWeaponry=False
EnableDinoDismountTeleport=True
PreventDinoDismountTeleportFlyers=False

Configs Explained

ForceEnableMountedWeaponry: If true, allows the rider to equip weapons on their dinos. Default: False
EnableDinoDismountTeleport: If true, when dismounting a dino, you will be teleported to the ground immediately. Default: True
PreventDinoDismountTeleportFlyers: If EnableDinoDismountTeleport is true and you want to prevent it from happening with flyers, enable this. Default: False

Flyer Seatbelts