diff --git a/Nasal/FMGC-b.nas b/Nasal/FMGC-b.nas
index edbd3c3b..30dcf644 100644
--- a/Nasal/FMGC-b.nas
+++ b/Nasal/FMGC-b.nas
@@ -672,8 +672,8 @@ var fpa_calc = func {
 }
 
 setlistener("/it-autoflight/input/kts-mach", func {
-	var ias = getprop("/instrumentation/airspeed-indicator/indicated-speed-kt");
-	var mach = getprop("/instrumentation/airspeed-indicator/indicated-mach");
+	var ias = getprop("/it-autoflight/input/spd-kts");
+	var mach = getprop("/it-autoflight/input/spd-mach");
 	if (getprop("/it-autoflight/input/kts-mach") == 0) {
 		if (ias >= 100 and ias <= 350) {
 			setprop("/it-autoflight/input/spd-kts", math.round(ias, 1));
diff --git a/revision.txt b/revision.txt
index d48e70e9..87172180 100644
--- a/revision.txt
+++ b/revision.txt
@@ -1 +1 @@
-4310
\ No newline at end of file
+4311
\ No newline at end of file