diff --git a/ai.c b/ai.c
--- a/ai.c
+++ b/ai.c
@@ -1494,20 +1494,17 @@ static void AiStateWantNewRoute(Player *
 
 		r = (uint16)Random();
 		
-		dis = _patches.ai_disable_veh;
-		if ((dis & 0xF) == 0xF) return; // no available vehicles at all?
-
 		if (r < 0x7626) {
-			if (dis&DISABLE_TRAINS) continue;
+			if (_patches.ai_disable_veh_train) continue;
 			AiWantTrainRoute(p);
 		} else if (r < 0xC4EA) {
-			if (dis&DISABLE_ROADVEH) continue;
+			if (_patches.ai_disable_veh_roadveh) continue;
 			AiWantRoadRoute(p);
 		} else if (r < 0xD89B) {
-			if (dis&DISABLE_AIRCRAFT) continue;
+			if (_patches.ai_disable_veh_aircraft) continue;
 			AiWantAircraftRoute(p);
 		} else {
-			if (dis&DISABLE_SHIPS) continue;
+			if (_patches.ai_disable_veh_ship) continue;
 			AiWantShipRoute(p);
 		}
 		
diff --git a/settings.c b/settings.c
--- a/settings.c
+++ b/settings.c
@@ -845,7 +845,10 @@ static const SettingDesc patch_settings[
 
 	{"build_in_pause",  SDT_BOOL, (void*)false, (void*)offsetof(Patches, build_in_pause)},
 
-	{"ai_disable_veh", SDT_UINT8, (void*)0, (void*)offsetof(Patches, ai_disable_veh)},
+	{"ai_disable_veh_train", SDT_BOOL, (void*)false, (void*)offsetof(Patches, ai_disable_veh_train)},
+	{"ai_disable_veh_roadveh", SDT_BOOL, (void*)false, (void*)offsetof(Patches, ai_disable_veh_roadveh)},
+	{"ai_disable_veh_aircraft", SDT_BOOL, (void*)false, (void*)offsetof(Patches, ai_disable_veh_aircraft)},
+	{"ai_disable_veh_ship", SDT_BOOL, (void*)false, (void*)offsetof(Patches, ai_disable_veh_ship)},
 	{"starting_date", SDT_UINT32, (void*)1950, (void*)offsetof(Patches, starting_date)},
 
 	{"colored_news_date", SDT_UINT32, (void*)2000, (void*)offsetof(Patches, colored_news_date)},
diff --git a/settings_gui.c b/settings_gui.c
--- a/settings_gui.c
+++ b/settings_gui.c
@@ -669,7 +669,6 @@ enum {
 	PE_INT16 = 2,
 	PE_UINT16 = 3,
 	PE_INT32 = 4,
-	PE_BYTE = 5,
 
 	PF_0ISDIS = 1,
 	PF_NOCOMMA = 2,
@@ -719,10 +718,10 @@ static const PatchEntry _patches_vehicle
 	{PE_UINT16, PF_0ISDIS, STR_CONFIG_PATCHES_SERVINT_AIRCRAFT, &_patches.servint_aircraft, 30, 1200, 10},
 	{PE_UINT16, PF_0ISDIS, STR_CONFIG_PATCHES_SERVINT_SHIPS, &_patches.servint_ships, 30, 1200, 10},
 
-	{PE_BYTE, 0, STR_CONFIG_PATCHES_AI_BUILDS_TRAINS, &_patches.ai_disable_veh, 0x01},
-	{PE_BYTE, 0, STR_CONFIG_PATCHES_AI_BUILDS_ROADVEH, &_patches.ai_disable_veh, 0x02},
-	{PE_BYTE, 0, STR_CONFIG_PATCHES_AI_BUILDS_AIRCRAFT, &_patches.ai_disable_veh, 0x04},
-	{PE_BYTE, 0, STR_CONFIG_PATCHES_AI_BUILDS_SHIPS, &_patches.ai_disable_veh, 0x08},
+	{PE_BOOL, 0, STR_CONFIG_PATCHES_AI_BUILDS_TRAINS, &_patches.ai_disable_veh_train},
+	{PE_BOOL, 0, STR_CONFIG_PATCHES_AI_BUILDS_ROADVEH, &_patches.ai_disable_veh_roadveh},
+	{PE_BOOL, 0, STR_CONFIG_PATCHES_AI_BUILDS_AIRCRAFT, &_patches.ai_disable_veh_aircraft},
+	{PE_BOOL, 0, STR_CONFIG_PATCHES_AI_BUILDS_SHIPS, &_patches.ai_disable_veh_ship},
 };
 
 static const PatchEntry _patches_stations[] = {
@@ -770,7 +769,6 @@ static int32 ReadPE(const PatchEntry*pe)
 	case PE_INT16:  return *(int16*)pe->variable;
 	case PE_UINT16: return *(uint16*)pe->variable;
 	case PE_INT32:  return *(int32*)pe->variable;
-	case PE_BYTE:   return *(byte*)pe->variable;
 	default:
 		NOT_REACHED();
 	}
@@ -779,52 +777,45 @@ static int32 ReadPE(const PatchEntry*pe)
 	return 0;
 }
 
-static void WritePE(const PatchEntry *pe, int32 val)
-{
-	switch(pe->type) {
-	case PE_BOOL: *(bool*)pe->variable = (bool)val; break;
-	case PE_BYTE: if ((byte)val > (byte)pe->max) 
-									*(byte*)pe->variable = (byte)pe->max;
-								else if ((byte)val < (byte)pe->min)
-									*(byte*)pe->variable = (byte)pe->min;
-								else
-									*(byte*)pe->variable = (byte)val;
-								break;
-
-	case PE_UINT8: if ((uint8)val > (uint8)pe->max) 
-									*(uint8*)pe->variable = (uint8)pe->max;
-								else if ((uint8)val < (uint8)pe->min)
-									*(uint8*)pe->variable = (uint8)pe->min;
-								else
-									*(uint8*)pe->variable = (uint8)val; 
-								break;
-
-	case PE_INT16: if ((int16)val > (int16)pe->max) 
-									*(int16*)pe->variable = (int16)pe->max;
-								else if ((int16)val < (int16)pe->min)
-									*(int16*)pe->variable = (int16)pe->min;
-								else
-									*(int16*)pe->variable = (int16)val; 
-								break;
-
-	case PE_UINT16: if ((uint16)val > (uint16)pe->max) 
-									*(uint16*)pe->variable = (uint16)pe->max;
-								else if ((uint16)val < (uint16)pe->min)
-									*(uint16*)pe->variable = (uint16)pe->min;
-								else
-									*(uint16*)pe->variable = (uint16)val; 
-								break;
-
-	case PE_INT32: if ((int32)val > (int32)pe->max) 
-									*(int32*)pe->variable = (int32)pe->max;
-								else if ((int32)val < (int32)pe->min)
-									*(int32*)pe->variable = (int32)pe->min;
-								else
-									*(int32*)pe->variable = val; 
-								break;
-	default:
-		NOT_REACHED();
-	}
+static void WritePE(const PatchEntry *pe, int32 val)
+{
+	switch(pe->type) {
+	case PE_BOOL: *(bool*)pe->variable = (bool)val; break;
+
+	case PE_UINT8: if ((uint8)val > (uint8)pe->max) 
+									*(uint8*)pe->variable = (uint8)pe->max;
+								else if ((uint8)val < (uint8)pe->min)
+									*(uint8*)pe->variable = (uint8)pe->min;
+								else
+									*(uint8*)pe->variable = (uint8)val; 
+								break;
+
+	case PE_INT16: if ((int16)val > (int16)pe->max) 
+									*(int16*)pe->variable = (int16)pe->max;
+								else if ((int16)val < (int16)pe->min)
+									*(int16*)pe->variable = (int16)pe->min;
+								else
+									*(int16*)pe->variable = (int16)val; 
+								break;
+
+	case PE_UINT16: if ((uint16)val > (uint16)pe->max) 
+									*(uint16*)pe->variable = (uint16)pe->max;
+								else if ((uint16)val < (uint16)pe->min)
+									*(uint16*)pe->variable = (uint16)pe->min;
+								else
+									*(uint16*)pe->variable = (uint16)val; 
+								break;
+
+	case PE_INT32: if ((int32)val > (int32)pe->max) 
+									*(int32*)pe->variable = (int32)pe->max;
+								else if ((int32)val < (int32)pe->min)
+									*(int32*)pe->variable = (int32)pe->min;
+								else
+									*(int32*)pe->variable = val; 
+								break;
+	default:
+		NOT_REACHED();
+	}
 }
 
 static void PatchesSelectionWndProc(Window *w, WindowEvent *e)
@@ -851,12 +842,6 @@ static void PatchesSelectionWndProc(Wind
 			if (pe->type == PE_BOOL) {
 				DrawFrameRect(x+5, y+1, x+15+9, y+9, (*(bool*)pe->variable)?6:4, (*(bool*)pe->variable)?0x20:0);
 				SET_DPARAM16(0, *(bool*)pe->variable ? STR_CONFIG_PATCHES_ON : STR_CONFIG_PATCHES_OFF);
-			} else if (pe->type == PE_BYTE) {
-				bool enabled;
-				val = ReadPE(pe);
-				enabled = (byte)val & (byte)pe->min;
-				DrawFrameRect(x+5, y+1, x+15+9, y+9, enabled?6:4, enabled?0x20:0);
-				SET_DPARAM16(0, enabled ? STR_CONFIG_PATCHES_ON : STR_CONFIG_PATCHES_OFF);
 			} else {
 				DrawFrameRect(x+5, y+1, x+5+9, y+9, 3, clk == i*2+1 ? 0x20 : 0);
 				DrawFrameRect(x+15, y+1, x+15+9, y+9, 3, clk == i*2+2 ? 0x20 : 0);
@@ -906,9 +891,6 @@ static void PatchesSelectionWndProc(Wind
 				case PE_BOOL:
 					val ^= 1;
 					break;
-				case PE_BYTE:
-					val ^= pe->min;
-					break;
 				case PE_UINT8:
 				case PE_INT16:
 				case PE_UINT16:
diff --git a/variables.h b/variables.h
--- a/variables.h
+++ b/variables.h
@@ -129,7 +129,10 @@ typedef struct Patches {
 	bool build_in_pause;		// build while in pause mode
 	bool bridge_pillars;		// show bridge pillars for high bridges
 
-	byte ai_disable_veh;		// mask of vehicle types to disable for ai
+	bool ai_disable_veh_train;		// disable types for AI
+	bool ai_disable_veh_roadveh;		// disable types for AI
+	bool ai_disable_veh_aircraft;		// disable types for AI
+	bool ai_disable_veh_ship;		// disable types for AI
 	uint32 starting_date;		// starting date
 	uint32 colored_news_date; // when does newspaper become colored?
 
@@ -149,13 +152,6 @@ typedef struct Patches {
 
 } Patches;
 
-enum {
-	DISABLE_TRAINS = 1<<0,
-	DISABLE_ROADVEH = 1 << 1,
-	DISABLE_AIRCRAFT = 1 << 2,
-	DISABLE_SHIPS = 1 << 3,
-};
-
 VARDEF Patches _patches;