diff --git a/src/engine.cpp b/src/engine.cpp
index ac2e8df0e..a416f4a21 100644
--- a/src/engine.cpp
+++ b/src/engine.cpp
@@ -429,14 +429,8 @@ uint Engine::GetDisplayWeight() const
uint Engine::GetDisplayMaxTractiveEffort() const
{
/* Only trains and road vehicles have 'tractive effort'. */
- switch (this->type) {
- case VEH_TRAIN:
- return (10 * this->GetDisplayWeight() * GetEngineProperty(this->index, PROP_TRAIN_TRACTIVE_EFFORT, this->u.rail.tractive_effort)) / 256;
- case VEH_ROAD:
- return (10 * this->GetDisplayWeight() * GetEngineProperty(this->index, PROP_ROADVEH_TRACTIVE_EFFORT, this->u.road.tractive_effort)) / 256;
-
- default: NOT_REACHED();
- }
+ assert(this->type == VEH_TRAIN || this->type == VEH_ROAD);
+ return (GROUND_ACCELERATION * this->GetDisplayWeight() * GetEngineProperty(this->index, this->type==VEH_TRAIN?PROP_TRAIN_TRACTIVE_EFFORT:PROP_ROADVEH_TRACTIVE_EFFORT, this->u.rail.tractive_effort)) / 256 / 1000;
}
/**
diff --git a/src/ground_vehicle.cpp b/src/ground_vehicle.cpp
index f8efd8e1a..6fd8d7710 100644
--- a/src/ground_vehicle.cpp
+++ b/src/ground_vehicle.cpp
@@ -58,7 +58,7 @@ void GroundVehicle<T, Type>::PowerChanged()
this->gcache.cached_air_drag = air_drag + 3 * air_drag * number_of_parts / 20;
- max_te *= 9800; // Tractive effort in (tonnes * 1000 * 9.8 =) N.
+ max_te *= GROUND_ACCELERATION; // Tractive effort in (tonnes * 1000 * 9.8 =) N.
max_te /= 256; // Tractive effort is a [0-255] coefficient.
if (this->gcache.cached_power != total_power || this->gcache.cached_max_te != max_te) {
/* Stop the vehicle if it has no power. */
diff --git a/src/vehicle_type.h b/src/vehicle_type.h
index 0921b39e3..f3e7d535f 100644
--- a/src/vehicle_type.h
+++ b/src/vehicle_type.h
@@ -17,6 +17,8 @@
/** The type all our vehicle IDs have. */
typedef uint32 VehicleID;
+static const int GROUND_ACCELERATION = 9800; ///< Acceleration due to gravity, 9.8 m/s^2
+
/** Available vehicle types. */
enum VehicleType {
VEH_BEGIN,