diff --git a/libraries/SITL/SIM_last_letter.cpp b/libraries/SITL/SIM_last_letter.cpp
index c4fd65e250..118884d130 100644
--- a/libraries/SITL/SIM_last_letter.cpp
+++ b/libraries/SITL/SIM_last_letter.cpp
@@ -107,8 +107,7 @@ void last_letter::recv_fdm(const struct sitl_input &input)
     location.alt = pkt.altitude*1.0e2;
     dcm.from_euler(pkt.roll, pkt.pitch, pkt.yaw);
 
-    // assume zero wind for now
-    airspeed = velocity_ef.length();
+    airspeed = pkt.airspeed;
 
     // auto-adjust to last_letter frame rate
     uint64_t deltat_us = pkt.timestamp_us - last_timestamp_us;