diff --git a/Aircraft/Instruments-3d/primus-1000/MFD/mfd-text.xml b/Aircraft/Instruments-3d/primus-1000/MFD/mfd-text.xml
index f92f91edd..80a93af7a 100644
--- a/Aircraft/Instruments-3d/primus-1000/MFD/mfd-text.xml
+++ b/Aircraft/Instruments-3d/primus-1000/MFD/mfd-text.xml
@@ -394,8 +394,7 @@ Primus 1000 MFD  hotspots
             <chunks>
                 <chunk>
                     <type>number-value</type>
-                    <property>velocities/uBody-fps</property>
-                    <scale>0.59248380</scale>
+                    <property>instrumentation/airspeed-indicator/true-speed-kt</property>
                     <format>%03.0f</format>
                 </chunk>
             </chunks>
diff --git a/Nasal/IOrules b/Nasal/IOrules
index a67bcf3da..71d2f677f 100644
--- a/Nasal/IOrules
+++ b/Nasal/IOrules
@@ -33,6 +33,7 @@ READ ALLOW $FG_SCENERY/*
 WRITE ALLOW /tmp/*.xml
 WRITE ALLOW $FG_HOME/*.sav
 WRITE ALLOW $FG_HOME/*.log
+WRITE ALLOW $FG_HOME/cache/*
 WRITE ALLOW $FG_HOME/Export/*
 WRITE ALLOW $FG_HOME/state/*.xml
 WRITE ALLOW $FG_HOME/aircraft-data/*.xml
diff --git a/Nasal/globals.nas b/Nasal/globals.nas
index 1413a8e23..d7bba2886 100644
--- a/Nasal/globals.nas
+++ b/Nasal/globals.nas
@@ -14,6 +14,9 @@ var M2NM = 1 / NM2M;
 var KT2MPS = 0.5144444444;             # knots to m/s
 var MPS2KT = 1 / KT2MPS;
 
+var FPS2KT = 0.5924838012958964;        # fps to knots
+var KT2FPS = 1 / FPS2KT;
+
 var LB2KG = 0.45359237;                # pounds to kg
 var KG2LB = 1 / LB2KG;