diff --git a/flightdata.py b/flightdata.py
index e2945ae..e00b19a 100755
--- a/flightdata.py
+++ b/flightdata.py
@@ -201,6 +201,8 @@ def aircraft_data(self, json_data, time):
             speed = 0
             if "speed" in a:
                 speed = geomath.knot2mph(a["speed"])
+            if "gs" in a:
+                speed = geomath.knot2mph(a["gs"])
             if "mach" in a:
                 speed = geomath.mach2mph(a["mach"])