The Airport Ramp mod for GTA 5 adds a huge ramp to the game, made up of pieces of an aircraft carrier and rising into the sky for a couple of kilometers. To install this modification, you need the Simple Trainer for GTA V 2.1 mod. Without it, you simply won't be able to run this mod.
To place an object in the game, open the Simple Trainer menu. Then follow the path: - Object Spawning - Save/load objects from objects.ini - Search for ini files in V's main Directory. After that select the mod file.