@@ -620,9 +620,15 @@ var displayClass = {

                     .hide();

         }

+        var Sy = 0;

+        for (var i = 8; i >= 0; i -= 1)

+            me._last_ias_Sy[i+1] = me._last_ias_Sy[i];

         var now = systime();

         # estimated speed in 6s

-        var Sy = 6 * (ias - me._last_ias_kt) / (now - me._last_ias_s);

+        me._last_ias_Sy[0] = 6 * (ias - me._last_ias_kt) / (now - me._last_ias_s);

+        foreach (var _Sy; me._last_ias_Sy)

+            Sy += _Sy;

+        Sy /= 10;

         if (abs(Sy) > 30)

             Sy = 30 * abs(Sy)/Sy; # = -30 or 30

         me.screenElements['Airspeed-Trend-Indicator']

@@ -634,6 +640,7 @@ var displayClass = {

     },

     _last_ias_kt : 0,

     _last_ias_s : systime(),

+    _last_ias_Sy : [0,0,0,0,0,0,0,0,0,0],

     _ias_already_exceeded : 0,

 #}}}

@@ -787,9 +794,15 @@ var displayClass = {

             }

         }

         me.updateSelectedALT();

+        var Sy = 0;

+        for (var i = 8; i >= 0; i -= 1)

+            me._last_alt_Sy[i+1] = me._last_alt_Sy[i];

         var now = systime();

         # altitude in 6s

-        var Sy = .3 * (alt - me._last_alt_ft) / (now - me._last_alt_s); # scale = 1/20ft

+        me._last_alt_Sy[0] = .3 * (alt - me._last_alt_ft) / (now - me._last_alt_s); # scale = 1/20ft

+        foreach (var _Sy; me._last_alt_Sy)

+            Sy += _Sy;

+        Sy /= 10;

         if (abs(Sy) > 15)

             Sy = 15 * abs(Sy)/Sy; # = -15 or 15

         me.screenElements['Altitude-Trend-Indicator']

@@ -800,6 +813,7 @@ var displayClass = {

         settimer(func me.updateALT(), 0.2);

     },

     _last_alt_ft : 0,

+    _last_alt_Sy : [0,0,0,0,0,0,0,0,0,0],

     _last_alt_s  : systime(),

 #}}}