belongsToMany( Airport::class, 'airports_planes',); } function planesToString() { $allPlanes = DB::table('airports_planes')->where('airport_id', $this->id)->get(); $str = ""; foreach ($allPlanes as $p) { $pl = Plane::where('id', $p->plane_id)->first(); $str = "$str $pl->model\n"; } return $str; } }