Move vehicle flyability to a flag, allow modifying flying vehicles

data/json/vehicleparts/rotor.json

@@ -7,7 +7,7 @@
     "color": "light_blue",
     "broken_symbol": "O",
     "broken_color": "light_gray",
-    "flags": [ "ROTOR", "NO_INSTALL_PLAYER", "NO_UNINSTALL", "NO_REPAIR", "NO_MODIFY_VEHICLE" ],
+    "flags": [ "ROTOR", "NO_INSTALL_PLAYER", "NO_UNINSTALL", "NO_REPAIR" ],
     "description": "A set of aerofoil helicopter rotors, when spun at high speed, they generate thrust via lift."
   },
   {

data/json/vehicleparts/vehicle_parts.json

@@ -127,7 +127,7 @@
       "removal": { "skills": [ [ "mechanics", 2 ] ], "time": "15 m", "using": [ [ "vehicle_bolt", 1 ] ] },
       "repair": { "skills": [ [ "mechanics", 2 ] ], "time": "30 m", "using": [ [ "welding_standard", 5 ] ] }
     },
-    "flags": [ "SEAT", "BOARDABLE", "CARGO", "BELTABLE" ],
+    "flags": [ "SEAT", "BOARDABLE", "CARGO", "BELTABLE", "SIMPLE_PART" ],
     "breaks_into": "ig_vp_seat",
     "damage_reduction": { "all": 2 }
   },
@@ -162,7 +162,7 @@
       "removal": { "skills": [ [ "mechanics", 2 ] ], "time": "15 m", "using": [ [ "vehicle_bolt", 1 ] ] },
       "repair": { "skills": [ [ "mechanics", 2 ] ], "time": "30 m", "using": [ [ "welding_standard", 5 ] ] }
     },
-    "flags": [ "BED", "SEAT", "BOARDABLE", "BELTABLE", "CARGO" ],
+    "flags": [ "BED", "SEAT", "BOARDABLE", "BELTABLE", "CARGO", "SIMPLE_PART" ],
     "breaks_into": "ig_vp_seat",
     "damage_reduction": { "all": 3 }
   },
@@ -589,7 +589,7 @@
       "removal": { "skills": [ [ "mechanics", 2 ] ], "time": "30 m", "using": [ [ "vehicle_bolt", 1 ] ] },
       "repair": { "skills": [ [ "mechanics", 3 ] ], "time": "60 m", "using": [ [ "welding_standard", 5 ] ] }
     },
-    "flags": [ "CARGO", "OBSTACLE", "OPENABLE", "BOARDABLE", "WINDOW" ],
+    "flags": [ "CARGO", "OBSTACLE", "OPENABLE", "BOARDABLE", "WINDOW", "SIMPLE_PART" ],
     "breaks_into": "ig_vp_frame",
     "damage_reduction": { "all": 21 }
   },
@@ -613,7 +613,7 @@
       "removal": { "skills": [ [ "mechanics", 2 ] ], "time": "30 m", "using": [ [ "vehicle_bolt", 1 ] ] },
       "repair": { "skills": [ [ "mechanics", 3 ] ], "time": "60 m", "using": [ [ "welding_standard", 5 ] ] }
     },
-    "flags": [ "CARGO", "OBSTACLE", "OPAQUE", "OPENABLE", "BOARDABLE" ],
+    "flags": [ "CARGO", "OBSTACLE", "OPAQUE", "OPENABLE", "BOARDABLE", "SIMPLE_PART" ],
     "breaks_into": "ig_vp_frame",
     "damage_reduction": { "all": 28 }
   },
@@ -637,7 +637,7 @@
       "removal": { "skills": [ [ "mechanics", 2 ] ], "time": "30 m", "using": [ [ "vehicle_bolt", 1 ] ] },
       "repair": { "skills": [ [ "mechanics", 3 ] ], "time": "60 m", "using": [ [ "welding_standard", 5 ] ] }
     },
-    "flags": [ "CARGO", "OBSTACLE", "OPENABLE", "BOARDABLE", "WINDOW" ],
+    "flags": [ "CARGO", "OBSTACLE", "OPENABLE", "BOARDABLE", "WINDOW", "SIMPLE_PART" ],
     "breaks_into": "ig_vp_hdframe",
     "damage_reduction": { "all": 68 }
   },
@@ -661,7 +661,7 @@
       "removal": { "skills": [ [ "mechanics", 2 ] ], "time": "30 m", "using": [ [ "vehicle_bolt", 1 ] ] },
       "repair": { "skills": [ [ "mechanics", 3 ] ], "time": "60 m", "using": [ [ "welding_standard", 5 ] ] }
     },
-    "flags": [ "CARGO", "OBSTACLE", "OPAQUE", "OPENABLE", "BOARDABLE" ],
+    "flags": [ "CARGO", "OBSTACLE", "OPAQUE", "OPENABLE", "BOARDABLE", "SIMPLE_PART" ],
     "breaks_into": "ig_vp_hdframe",
     "damage_reduction": { "all": 75 }
   },
@@ -684,7 +684,7 @@
       "removal": { "skills": [ [ "mechanics", 2 ] ], "time": "30 m", "using": [ [ "vehicle_bolt", 1 ] ] },
       "repair": { "skills": [ [ "mechanics", 3 ] ], "time": "60 m", "using": [ [ "welding_standard", 5 ] ] }
     },
-    "flags": [ "OBSTACLE", "OPAQUE", "OPENABLE", "ROOF", "BOARDABLE" ],
+    "flags": [ "OBSTACLE", "OPAQUE", "OPENABLE", "ROOF", "BOARDABLE", "SIMPLE_PART" ],
     "breaks_into": "ig_vp_frame",
     "damage_reduction": { "all": 28 }
   },
@@ -708,7 +708,7 @@
       "removal": { "skills": [ [ "mechanics", 2 ] ], "time": "30 m", "using": [ [ "vehicle_weld_removal", 1 ] ] },
       "repair": { "skills": [ [ "mechanics", 3 ] ], "time": "60 m", "using": [ [ "welding_standard", 5 ] ] }
     },
-    "flags": [ "CARGO", "LOCKABLE_CARGO", "OBSTACLE", "OPENABLE", "MULTISQUARE", "BOARDABLE", "COVERED" ],
+    "flags": [ "CARGO", "LOCKABLE_CARGO", "OBSTACLE", "OPENABLE", "MULTISQUARE", "BOARDABLE", "COVERED", "SIMPLE_PART" ],
     "breaks_into": "ig_vp_frame",
     "damage_reduction": { "all": 30 }
   },
@@ -732,7 +732,7 @@
       "removal": { "skills": [ [ "mechanics", 2 ] ], "time": "30 m", "using": [ [ "vehicle_weld_removal", 1 ] ] },
       "repair": { "skills": [ [ "mechanics", 3 ] ], "time": "60 m", "using": [ [ "welding_standard", 5 ] ] }
     },
-    "flags": [ "CARGO", "LOCKABLE_CARGO", "OBSTACLE", "OPENABLE", "MULTISQUARE", "BOARDABLE", "COVERED", "OPAQUE" ],
+    "flags": [ "CARGO", "LOCKABLE_CARGO", "OBSTACLE", "OPENABLE", "MULTISQUARE", "BOARDABLE", "COVERED", "OPAQUE", "SIMPLE_PART" ],
     "breaks_into": "ig_vp_frame",
     "damage_reduction": { "all": 34 }
   },
@@ -756,7 +756,7 @@
       "removal": { "skills": [ [ "mechanics", 2 ] ], "time": "30 m", "using": [ [ "vehicle_weld_removal", 1 ] ] },
       "repair": { "skills": [ [ "mechanics", 4 ] ], "time": "60 m", "using": [ [ "welding_standard", 5 ] ] }
     },
-    "flags": [ "CARGO", "LOCKABLE_CARGO", "OBSTACLE", "OPENABLE", "MULTISQUARE", "BOARDABLE", "COVERED" ],
+    "flags": [ "CARGO", "LOCKABLE_CARGO", "OBSTACLE", "OPENABLE", "MULTISQUARE", "BOARDABLE", "COVERED", "SIMPLE_PART" ],
     "breaks_into": "ig_vp_hdframe",
     "damage_reduction": { "all": 78 }
   },
@@ -780,7 +780,7 @@
       "removal": { "skills": [ [ "mechanics", 2 ] ], "time": "30 m", "using": [ [ "vehicle_weld_removal", 1 ] ] },
       "repair": { "skills": [ [ "mechanics", 4 ] ], "time": "60 m", "using": [ [ "welding_standard", 5 ] ] }
     },
-    "flags": [ "CARGO", "LOCKABLE_CARGO", "OBSTACLE", "OPENABLE", "MULTISQUARE", "BOARDABLE", "COVERED", "OPAQUE" ],
+    "flags": [ "CARGO", "LOCKABLE_CARGO", "OBSTACLE", "OPENABLE", "MULTISQUARE", "BOARDABLE", "COVERED", "OPAQUE", "SIMPLE_PART" ],
     "breaks_into": "ig_vp_hdframe",
     "damage_reduction": { "all": 80 }
   },
@@ -1154,7 +1154,7 @@
       "removal": { "skills": [ [ "mechanics", 2 ] ], "time": "30 m", "using": [ [ "vehicle_weld_removal", 1 ] ] },
       "repair": { "skills": [ [ "mechanics", 2 ] ], "time": "60 m", "using": [ [ "welding_standard", 5 ] ] }
     },
-    "flags": [ "CARGO", "LOCKABLE_CARGO", "COVERED", "BOARDABLE" ],
+    "flags": [ "CARGO", "LOCKABLE_CARGO", "COVERED", "BOARDABLE", "SIMPLE_PART" ],
     "breaks_into": "ig_vp_frame",
     "damage_reduction": { "all": 30 }
   },
@@ -2628,7 +2628,7 @@
       "removal": { "skills": [ [ "mechanics", 2 ] ], "time": "30 m", "using": [ [ "vehicle_bolt", 1 ] ] },
       "repair": { "skills": [ [ "mechanics", 3 ] ], "time": "60 m", "using": [ [ "welding_standard", 5 ] ] }
     },
-    "flags": [ "OBSTACLE", "OPENABLE", "MULTISQUARE", "BOARDABLE", "LOW_FINAL_AIR_DRAG", "NO_ROOF_NEEDED", "WINDOW" ],
+    "flags": [ "OBSTACLE", "OPENABLE", "MULTISQUARE", "BOARDABLE", "LOW_FINAL_AIR_DRAG", "NO_ROOF_NEEDED", "WINDOW", "SIMPLE_PART" ],
     "breaks_into": "ig_vp_frame",
     "damage_reduction": { "all": 25 }
   },
@@ -2651,7 +2651,7 @@
       "removal": { "skills": [ [ "mechanics", 2 ] ], "time": "30 m", "using": [ [ "vehicle_bolt", 1 ] ] },
       "repair": { "skills": [ [ "mechanics", 3 ] ], "time": "60 m", "using": [ [ "welding_standard", 5 ] ] }
     },
-    "flags": [ "OBSTACLE", "OPENABLE", "MULTISQUARE", "BOARDABLE", "LOW_FINAL_AIR_DRAG", "WINDOW" ],
+    "flags": [ "OBSTACLE", "OPENABLE", "MULTISQUARE", "BOARDABLE", "LOW_FINAL_AIR_DRAG", "WINDOW", "SIMPLE_PART" ],
     "breaks_into": "ig_vp_hdframe",
     "damage_reduction": { "all": 78 }
   },
@@ -2674,7 +2674,7 @@
       "removal": { "skills": [ [ "mechanics", 2 ] ], "time": "30 m", "using": [ [ "vehicle_bolt", 1 ] ] },
       "repair": { "skills": [ [ "mechanics", 3 ] ], "time": "60 m", "using": [ [ "welding_standard", 5 ] ] }
     },
-    "flags": [ "OPAQUE", "OBSTACLE", "OPENABLE", "MULTISQUARE", "BOARDABLE" ],
+    "flags": [ "OPAQUE", "OBSTACLE", "OPENABLE", "MULTISQUARE", "BOARDABLE", "SIMPLE_PART" ],
     "breaks_into": "ig_vp_sheet_metal",
     "damage_reduction": { "all": 24 }
   },
@@ -2697,7 +2697,7 @@
       "removal": { "skills": [ [ "mechanics", 2 ] ], "time": "30 m", "using": [ [ "vehicle_bolt", 1 ] ] },
       "repair": { "skills": [ [ "mechanics", 3 ] ], "time": "60 m", "using": [ [ "welding_standard", 5 ] ] }
     },
-    "flags": [ "OBSTACLE", "OPENABLE", "MULTISQUARE", "BOARDABLE" ],
+    "flags": [ "OBSTACLE", "OPENABLE", "MULTISQUARE", "BOARDABLE", "SIMPLE_PART" ],
     "breaks_into": "ig_vp_frame",
     "damage_reduction": { "all": 26 }
   },
@@ -3044,7 +3044,7 @@
       "removal": { "skills": [ [ "mechanics", 2 ] ], "time": "15 m", "using": [ [ "vehicle_nail_removal", 1 ] ] },
       "repair": { "skills": [ [ "mechanics", 3 ] ], "time": "30 m", "using": [ [ "adhesive", 2 ] ] }
     },
-    "flags": [ "OBSTACLE", "OPENABLE", "BOARDABLE", "WINDOW" ],
+    "flags": [ "OBSTACLE", "OPENABLE", "BOARDABLE", "WINDOW", "SIMPLE_PART" ],
     "breaks_into": [ { "item": "splinter", "count": [ 7, 9 ] } ],
     "damage_reduction": { "all": 8 }
   },
@@ -3067,7 +3067,7 @@
       "removal": { "skills": [ [ "mechanics", 2 ] ], "time": "15 m", "using": [ [ "vehicle_nail_removal", 1 ] ] },
       "repair": { "skills": [ [ "mechanics", 3 ] ], "time": "30 m", "using": [ [ "adhesive", 2 ] ] }
     },
-    "flags": [ "OBSTACLE", "OPENABLE", "BOARDABLE", "OPAQUE" ],
+    "flags": [ "OBSTACLE", "OPENABLE", "BOARDABLE", "OPAQUE", "SIMPLE_PART" ],
     "breaks_into": [ { "item": "splinter", "count": [ 7, 9 ] } ],
     "damage_reduction": { "all": 12 }
   },

src/activity_handlers.h

@@ -60,6 +60,7 @@ enum class do_activity_reason : int {
     ALREADY_WORKING,        // somebody is already working there
     NEEDS_VEH_DECONST,       // There is a vehicle part there that we can deconstruct, given the right tools.
     NEEDS_VEH_REPAIR,       // There is a vehicle part there that can be repaired, given the right tools.
+    WOULD_PREVENT_VEH_FLYING, // Attempting to perform this activity on a vehicle would prevent it from flying
     NEEDS_MINING,           // This spot can be mined, if the right tool is present.
     NEEDS_FISHING           // This spot can be fished, if the right tool is present.
 };

src/activity_item_handling.cpp

@@ -1128,6 +1128,10 @@ static activity_reason_info can_do_activity_there( const activity_id &act, playe
                 if( vpindex == -1 || !veh->can_unmount( vpindex ) ) {
                     continue;
                 }
+                // If removing this part would make the vehicle non-flyable, avoid it
+                if( veh->would_prevent_flyable( vpinfo ) ) {
+                    return activity_reason_info::fail( do_activity_reason::WOULD_PREVENT_VEH_FLYING );
+                }
                 // this is the same part that somebody else wants to work on, or already is.
                 if( std::find( already_working_indexes.begin(), already_working_indexes.end(),
                                vpindex ) != already_working_indexes.end() ) {
@@ -1174,6 +1178,10 @@ static activity_reason_info can_do_activity_there( const activity_id &act, playe
                     part_elem->info().repair_requirements().is_empty() ) {
                     continue;
                 }
+                // If repairing this part would make the vehicle non-flyable, avoid it
+                if( veh->would_prevent_flyable( vpinfo ) ) {
+                    return activity_reason_info::fail( do_activity_reason::WOULD_PREVENT_VEH_FLYING );
+                }
                 if( std::find( already_working_indexes.begin(), already_working_indexes.end(),
                                vpindex ) != already_working_indexes.end() ) {
                     continue;

src/handle_action.cpp

@@ -474,13 +474,19 @@ static void pldrive( const tripoint &p )
             return;
         }
     }
-    if( p.z != 0 && !u.has_trait( trait_PROF_HELI_PILOT ) ) {
-        u.add_msg_if_player( m_info, _( "You have no idea how to make the vehicle fly." ) );
-        return;
-    }
-    if( p.z != 0 && !g->m.has_zlevels() ) {
-        u.add_msg_if_player( m_info, _( "This vehicle doesn't look very airworthy." ) );
-        return;
+    if( p.z != 0 ) {
+        if( !u.has_trait( trait_PROF_HELI_PILOT ) ) {
+            u.add_msg_if_player( m_info, _( "You have no idea how to make the vehicle fly." ) );
+            return;
+        }
+        if( !veh->is_flyable() ) {
+            u.add_msg_if_player( m_info, _( "This vehicle doesn't look very airworthy." ) );
+            return;
+        }
+        if( !g->m.has_zlevels() ) {
+            u.add_msg_if_player( m_info, _( "This vehicle cannot be flown without z levels." ) );
+            return;
+        }
     }
     if( p.z == -1 ) {
         if( veh->check_heli_descend( u ) ) {

src/savegame_json.cpp

@@ -2692,6 +2692,7 @@ void vehicle::deserialize( JsonIn &jsin )
     data.read( "is_following", is_following );
     data.read( "is_patrolling", is_patrolling );
     data.read( "autodrive_local_target", autodrive_local_target );
+    data.read( "airworthy", flyable );
     data.read( "summon_time_limit", summon_time_limit );
     data.read( "magic", magic );
     // Need to manually backfill the active item cache since the part loader can't call its vehicle.
@@ -2854,6 +2855,7 @@ void vehicle::serialize( JsonOut &json ) const
     json.member( "is_following", is_following );
     json.member( "is_patrolling", is_patrolling );
     json.member( "autodrive_local_target", autodrive_local_target );
+    json.member( "airworthy", flyable );
     json.member( "summon_time_limit", summon_time_limit );
     json.member( "magic", magic );
     json.end_object();

src/veh_interact.cpp

@@ -1047,6 +1047,16 @@ bool veh_interact::do_install( std::string &msg )
                     default:
                         break;
                 }
+                // Modifying a vehicle with rotors will make in not flightworthy (until we've got a better model)
+                // It can only be the player doing this - an npc won't work well with query_yn
+                if( veh->would_prevent_flyable( *sel_vpart_info ) ) {
+                    if( query_yn(
+                            _( "Installing this part will mean that this vehicle is no longer flightworthy.  Continue?" ) ) ) {
+                        veh->set_flyable( false );
+                    } else {
+                        return false;
+                    }
+                }
                 if( veh->is_foldable() && !sel_vpart_info->has_flag( "FOLDABLE" ) &&
                     !query_yn( _( "Installing this part will make the vehicle unfoldable.  Continue?" ) ) ) {
                     return true;
@@ -1182,7 +1192,8 @@ bool veh_interact::do_repair( std::string &msg )
 
         std::string nmsg;
 
-        bool ok;
+        // this will always be set, but the gcc thinks that sometimes it won't be
+        bool ok = true;
         if( pt.is_broken() ) {
             ok = format_reqs( nmsg, vp.install_requirements(), vp.install_skills, vp.install_time( g->u ) );
         } else {
@@ -1193,6 +1204,17 @@ bool veh_interact::do_repair( std::string &msg )
             } else if( veh->has_part( "NO_MODIFY_VEHICLE" ) && !vp.has_flag( "SIMPLE_PART" ) ) {
                 nmsg += colorize( _( "This vehicle cannot be repaired.\n" ), c_light_red );
                 ok = false;
+            } else if( veh->would_prevent_flyable( vp ) ) {
+                // Modifying a vehicle with rotors will make in not flightworthy (until we've got a better model)
+                // It can only be the player doing this - an npc won't work well with query_yn
+                if( query_yn(
+                        _( "Repairing this part will mean that this vehicle is no longer flightworthy.  Continue?" ) ) ) {
+                    veh->set_flyable( false );
+                } else {
+                    nmsg += colorize( _( "You chose not to install this part to keep the vehicle flyable.\n" ),
+                                      c_light_red );
+                    ok = false;
+                }
             } else {
                 ok = format_reqs( nmsg, vp.repair_requirements() * pt.base.damage_level( 4 ), vp.repair_skills,
                                   vp.repair_time( g->u ) * pt.base.damage() / pt.base.max_damage() );
@@ -1862,6 +1884,17 @@ bool veh_interact::do_remove( std::string &msg )
                 default:
                     break;
             }
+
+            // Modifying a vehicle with rotors will make in not flightworthy (until we've got a better model)
+            // It can only be the player doing this - an npc won't work well with query_yn
+            if( veh->would_prevent_flyable( veh->parts[part].info() ) ) {
+                if( query_yn(
+                        _( "Removing this part will mean that this vehicle is no longer flightworthy.  Continue?" ) ) ) {
+                    veh->set_flyable( false );
+                } else {
+                    return false;
+                }
+            }
             const std::vector<npc *> helpers = g->u.get_crafting_helpers();
             for( const npc *np : helpers ) {
                 add_msg( m_info, _( "%s helps with this task…" ), np->name );

src/veh_type.cpp

@@ -73,6 +73,7 @@ static const std::unordered_map<std::string, vpart_bitflags> vpart_bitflag_map =
     { "SEATBELT", VPFLAG_SEATBELT },
     { "WHEEL", VPFLAG_WHEEL },
     { "ROTOR", VPFLAG_ROTOR },
+    { "ROTOR_SIMPLE", VPFLAG_ROTOR_SIMPLE },
     { "FLOATS", VPFLAG_FLOATS },
     { "DOME_LIGHT", VPFLAG_DOME_LIGHT },
     { "AISLE_LIGHT", VPFLAG_AISLE_LIGHT },
@@ -421,7 +422,7 @@ void vpart_info::load( const JsonObject &jo, const std::string &src )
         load_wheel( def.wheel_info, jo );
     }
 
-    if( def.has_flag( "ROTOR" ) ) {
+    if( def.has_flag( "ROTOR" ) || def.has_flag( "ROTOR_SIMPLE" ) ) {
         load_rotor( def.rotor_info, jo );
     }
 
@@ -892,7 +893,10 @@ float vpart_info::wheel_or_rating() const
 
 int vpart_info::rotor_diameter() const
 {
-    return has_flag( VPFLAG_ROTOR ) ? rotor_info->rotor_diameter : 0;
+    if( has_flag( VPFLAG_ROTOR ) || has_flag( VPFLAG_ROTOR_SIMPLE ) ) {
+        return rotor_info->rotor_diameter;
+    }
+    return 0;
 }
 
 const cata::optional<vpslot_workbench> &vpart_info::get_workbench_info() const

src/veh_type.h

@@ -49,6 +49,7 @@ enum vpart_bitflags : int {
     VPFLAG_COOLER,
     VPFLAG_WHEEL,
     VPFLAG_ROTOR,
+    VPFLAG_ROTOR_SIMPLE,
     VPFLAG_MOUNTABLE,
     VPFLAG_FLOATS,
     VPFLAG_DOME_LIGHT,

src/vehicle.cpp

@@ -3933,6 +3933,7 @@ double vehicle::coeff_air_drag() const
             d_check_max( drag[ col ].panel, pa, pa.info().has_flag( "SOLAR_PANEL" ) );
             d_check_max( drag[ col ].windmill, pa, pa.info().has_flag( "WIND_TURBINE" ) );
             d_check_max( drag[ col ].rotor, pa, pa.info().has_flag( "ROTOR" ) );
+            d_check_max( drag[ col ].rotor, pa, pa.info().has_flag( "ROTOR_SIMPLE" ) );
             d_check_max( drag[ col ].sail, pa, pa.info().has_flag( "WIND_POWERED" ) );
             d_check_max( drag[ col ].exposed, pa, d_exposed( pa ) );
             d_check_min( drag[ col ].last, pa, pa.info().has_flag( "LOW_FINAL_AIR_DRAG" ) ||
@@ -4094,14 +4095,30 @@ bool vehicle::has_sufficient_rotorlift() const
 
 bool vehicle::is_rotorcraft() const
 {
-    return has_part( "ROTOR" ) && has_sufficient_rotorlift() && player_in_control( g->u );
+    return ( has_part( "ROTOR" ) || has_part( "ROTOR_SIMPLE" ) ) && has_sufficient_rotorlift() &&
+           player_in_control( g->u );
+}
+
+bool vehicle::is_flyable() const
+{
+    return flyable;
+}
+
+void vehicle::set_flyable( bool val )
+{
+    flyable = val;
 }
 
 int vehicle::get_z_change() const
 {
     return requested_z_change;
 }
 
+bool vehicle::would_prevent_flyable( const vpart_info &vpinfo ) const
+{
+    return is_flyable() && has_part( "ROTOR" ) && !vpinfo.has_flag( "SIMPLE_PART" );
+}
+
 bool vehicle::is_flying_in_air() const
 {
     return is_flying;
@@ -5502,7 +5519,7 @@ void vehicle::refresh()
         if( vpi.has_flag( VPFLAG_SOLAR_PANEL ) ) {
             solar_panels.push_back( p );
         }
-        if( vpi.has_flag( VPFLAG_ROTOR ) ) {
+        if( vpi.has_flag( VPFLAG_ROTOR ) || vpi.has_flag( VPFLAG_ROTOR_SIMPLE ) ) {
             rotors.push_back( p );
         }
         if( vpi.has_flag( "WIND_TURBINE" ) ) {