diff --git a/addons/parachute/functions/fnc_showAltimeter.sqf b/addons/parachute/functions/fnc_showAltimeter.sqf
index a8200fb2ca..45816cc883 100644
--- a/addons/parachute/functions/fnc_showAltimeter.sqf
+++ b/addons/parachute/functions/fnc_showAltimeter.sqf
@@ -14,19 +14,24 @@
  * Public: Yes
  */
 #include "script_component.hpp"
+
 private ["_unit"];
+
 _unit = _this select 0;
-(["ACE_Altimeter"] call BIS_fnc_rscLayer) cutRsc ["ACE_Altimeter", "PLAIN",0,true];
+
+(["ACE_Altimeter"] call BIS_fnc_rscLayer) cutRsc ["ACE_Altimeter", "PLAIN", 0, true];
 if (isNull (uiNamespace getVariable ["ACE_Altimeter", displayNull])) exitWith {};
 
 GVAR(AltimeterActive) = true;
+
 [{
-    if (!GVAR(AltimeterActive)) exitWith {[_this select 1] call CALLSTACK(cba_fnc_removePerFrameEventHandler);};
+    if (!GVAR(AltimeterActive)) exitWith {[_this select 1] call CALLSTACK(cba_fnc_removePerFrameEventHandler)};
     disableSerialization;
     EXPLODE_4_PVT(_this select 0,_display,_unit,_oldHeight,_prevTime);
-    if !("ACE_Altimeter" in assignedItems _unit) exitWith {[_this select 1] call CALLSTACK(cba_fnc_removePerFrameEventHandler);call FUNC(hideAltimeter);};
+    if !("ACE_Altimeter" in assignedItems _unit) exitWith {[_this select 1] call CALLSTACK(cba_fnc_removePerFrameEventHandler); call FUNC(hideAltimeter)};
+
+    private ["_height", "_hour", "_minute", "_descentRate","_HeightText", "_DecendRate", "_TimeText", "_curTime", "_timeDiff"];
 
-    private ["_height", "_hour", "_minute", "_descentRate","_HeightText", "_DecendRate", "_TimeText", "_curTime"];
     _HeightText = _display displayCtrl 1100;
     _DecendRate = _display displayCtrl 1000;
     _TimeText = _display displayCtrl 1001;
@@ -35,7 +40,8 @@ GVAR(AltimeterActive) = true;
 
     _height = (getPosASL _unit) select 2;
     _curTime = time;
-    _descentRate = floor ((_oldHeight - _height) / (_curTime - _prevTime));
+    _timeDiff = _curTime - _prevTime;
+    _descentRate = if(_timeDiff > 0) then {floor((_oldHeight - _height) / _timeDiff)} else {0};
 
     _TimeText ctrlSetText (format ["%1:%2",[_hour, 2] call EFUNC(common,numberToDigitsString),[_minute, 2] call EFUNC(common,numberToDigitsString)]);
     _HeightText ctrlSetText (format ["%1", floor(_height)]);