diff --git a/src/saveload/afterload.cpp b/src/saveload/afterload.cpp
index 676111eb76..5a6454f099 100644
--- a/src/saveload/afterload.cpp
+++ b/src/saveload/afterload.cpp
@@ -2937,6 +2937,21 @@ bool AfterLoadGame()
 			}
 		}
 	}
+	if (!SlXvIsFeaturePresent(XSLFI_IMPROVED_BREAKDOWNS, 4)) {
+		Vehicle *v;
+		FOR_ALL_VEHICLES(v) {
+			switch(v->type) {
+				case VEH_AIRCRAFT:
+					if (v->breakdown_type == BREAKDOWN_AIRCRAFT_SPEED && v->breakdown_severity == 0) {
+						v->breakdown_severity = max(1, min(v->vcache.cached_max_speed >> 4, 255));
+					}
+					break;
+
+				default:
+					break;
+			}
+		}
+	}
 
 	/* The road owner of standard road stops was not properly accounted for. */
 	if (IsSavegameVersionBefore(172)) {
diff --git a/src/saveload/extended_ver_sl.cpp b/src/saveload/extended_ver_sl.cpp
index 2346ebb767..92e8388157 100644
--- a/src/saveload/extended_ver_sl.cpp
+++ b/src/saveload/extended_ver_sl.cpp
@@ -55,7 +55,7 @@ const SlxiSubChunkInfo _sl_xv_sub_chunk_infos[] = {
 	{ XSLFI_TIMETABLES_START_TICKS, XSCF_NULL,                2,   2, "timetable_start_ticks",     NULL, NULL, NULL        },
 	{ XSLFI_TOWN_CARGO_ADJ,         XSCF_IGNORABLE_UNKNOWN,   1,   1, "town_cargo_adj",            NULL, NULL, NULL        },
 	{ XSLFI_SIG_TUNNEL_BRIDGE,      XSCF_NULL,                2,   2, "signal_tunnel_bridge",      NULL, NULL, NULL        },
-	{ XSLFI_IMPROVED_BREAKDOWNS,    XSCF_NULL,                3,   3, "improved_breakdowns",       NULL, NULL, NULL        },
+	{ XSLFI_IMPROVED_BREAKDOWNS,    XSCF_NULL,                4,   4, "improved_breakdowns",       NULL, NULL, NULL        },
 	{ XSLFI_TT_WAIT_IN_DEPOT,       XSCF_NULL,                1,   1, "tt_wait_in_depot",          NULL, NULL, NULL        },
 	{ XSLFI_AUTO_TIMETABLE,         XSCF_NULL,                4,   4, "auto_timetables",           NULL, NULL, NULL        },
 	{ XSLFI_VEHICLE_REPAIR_COST,    XSCF_NULL,                1,   1, "vehicle_repair_cost",       NULL, NULL, NULL        },
diff --git a/src/vehicle.cpp b/src/vehicle.cpp
index 1e82f1adf0..ca03a22ab4 100644
--- a/src/vehicle.cpp
+++ b/src/vehicle.cpp
@@ -1386,8 +1386,8 @@ void DetermineBreakdownType(Vehicle *v, uint32 r) {
 		if (rand <= breakdown_type_chance[BREAKDOWN_AIRCRAFT_SPEED]) {
 			v->breakdown_type = BREAKDOWN_AIRCRAFT_SPEED;
 			/* all speed values here are 1/8th of the real max speed in km/h */
-			byte max_speed = min(AircraftVehInfo( v->engine_type )->max_speed >> 3, 255);
-			byte min_speed = min(15 + (max_speed >> 2), AircraftVehInfo(v->engine_type)->max_speed >> 4);
+			byte max_speed = max(1, min(v->vcache.cached_max_speed >> 3, 255));
+			byte min_speed = max(1, min(15 + (max_speed >> 2), v->vcache.cached_max_speed >> 4));
 			v->breakdown_severity = min_speed + (((v->reliability + GB(r, 16, 16)) * (max_speed - min_speed)) >> 17);
 		} else if (rand <= breakdown_type_chance[BREAKDOWN_AIRCRAFT_DEPOT]) {
 			v->breakdown_type = BREAKDOWN_AIRCRAFT_DEPOT;