diff --git a/src/actor.h b/src/actor.h
index 768008182..bf1b1cc60 100644
--- a/src/actor.h
+++ b/src/actor.h
@@ -332,6 +332,7 @@ enum
 	MF6_INTRYMOVE		= 0x10000000,	// Executing P_TryMove
 	MF6_NOTAUTOAIMED	= 0x20000000,	// Do not subject actor to player autoaim.
 	MF6_NOTONAUTOMAP	= 0x40000000,	// will not be shown on automap with the 'scanner' powerup.
+	MF6_RELATIVETOFLOOR	= 0x80000000,	// [RC] Make flying actors be affected by lifts.
 
 // --- mobj.renderflags ---
 
diff --git a/src/p_map.cpp b/src/p_map.cpp
index da87481d0..ee7c63263 100644
--- a/src/p_map.cpp
+++ b/src/p_map.cpp
@@ -5047,6 +5047,15 @@ void PIT_FloorDrop (AActor *thing, FChangePosition *cpos)
 			P_CheckFakeFloorTriggers (thing, oldz);
 		}
 	}
+	else if ((thing->z != oldfloorz && !(thing->flags & MF_NOLIFTDROP)))
+	{
+		fixed_t oldz = thing->z;
+		if ((thing->flags & MF_NOGRAVITY) && (thing->flags6 & MF6_RELATIVETOFLOOR))
+		{
+			thing->z = thing->z - oldfloorz + thing->floorz;
+			P_CheckFakeFloorTriggers (thing, oldz);
+		}
+	}
 }
 
 //=============================================================================
@@ -5058,6 +5067,7 @@ void PIT_FloorDrop (AActor *thing, FChangePosition *cpos)
 void PIT_FloorRaise (AActor *thing, FChangePosition *cpos)
 {
 	fixed_t oldfloorz = thing->floorz;
+	fixed_t oldz = thing->z;
 
 	P_AdjustFloorCeil (thing, cpos);
 
@@ -5072,22 +5082,30 @@ void PIT_FloorRaise (AActor *thing, FChangePosition *cpos)
 			return; // do not move bridge things
 		}
 		intersectors.Clear ();
-		fixed_t oldz = thing->z;
 		thing->z = thing->floorz;
-		switch (P_PushUp (thing, cpos))
+	}
+	else
+	{
+		if((thing->flags & MF_NOGRAVITY) && (thing->flags6 & MF6_RELATIVETOFLOOR))
 		{
-		default:
-			P_CheckFakeFloorTriggers (thing, oldz);
-			break;
-		case 1:
-			P_DoCrunch (thing, cpos);
-			P_CheckFakeFloorTriggers (thing, oldz);
-			break;
-		case 2:
-			P_DoCrunch (thing, cpos);
-			thing->z = oldz;
-			break;
+			intersectors.Clear ();
+			thing->z = thing->z - oldfloorz + thing->floorz;
 		}
+		else return;
+	}
+	switch (P_PushUp (thing, cpos))
+	{
+	default:
+		P_CheckFakeFloorTriggers (thing, oldz);
+		break;
+	case 1:
+		P_DoCrunch (thing, cpos);
+		P_CheckFakeFloorTriggers (thing, oldz);
+		break;
+	case 2:
+		P_DoCrunch (thing, cpos);
+		thing->z = oldz;
+		break;
 	}
 }
 
diff --git a/src/thingdef/thingdef_data.cpp b/src/thingdef/thingdef_data.cpp
index ef0cf2fe1..c01855eec 100644
--- a/src/thingdef/thingdef_data.cpp
+++ b/src/thingdef/thingdef_data.cpp
@@ -235,6 +235,7 @@ static FFlagDef ActorFlags[]=
 	DEFINE_FLAG(MF6, POISONALWAYS, AActor, flags6),
 	DEFINE_FLAG(MF6, NOTAUTOAIMED, AActor, flags6),
 	DEFINE_FLAG(MF6, NOTONAUTOMAP, AActor, flags6),
+	DEFINE_FLAG(MF6, RELATIVETOFLOOR, AActor, flags6),
 
 	// Effect flags
 	DEFINE_FLAG(FX, VISIBILITYPULSE, AActor, effects),