From d62796c19df2ee92bb3a837e271ca0dcb9fd0c92 Mon Sep 17 00:00:00 2001
From: Scott Giese <scttgs0@gmail.com>
Date: Fri, 23 Oct 2020 23:26:28 -0500
Subject: [PATCH] METAR: When Wind unit not specified, default to knots.

FLIGHTGEAR-F6 resolved
---
 simgear/environment/metar.cxx      | 2 ++
 simgear/environment/test_metar.cxx | 9 +++++++++
 2 files changed, 11 insertions(+)

diff --git a/simgear/environment/metar.cxx b/simgear/environment/metar.cxx
index 08e72bfb..4bd5f0e1 100644
--- a/simgear/environment/metar.cxx
+++ b/simgear/environment/metar.cxx
@@ -659,6 +659,8 @@ bool SGMetar::scanWind()
 		m += 3, factor = SG_KMH_TO_MPS;
 	else if (!strncmp(m, "MPS", 3))
 		m += 3, factor = 1.0;
+	else if (!strncmp(m, " ", 1))		// default to Knots
+		factor = SG_KT_TO_MPS;
 	else
 		return false;
 	if (!scanBoundary(&m))
diff --git a/simgear/environment/test_metar.cxx b/simgear/environment/test_metar.cxx
index bf5d2cbe..6fc03607 100644
--- a/simgear/environment/test_metar.cxx
+++ b/simgear/environment/test_metar.cxx
@@ -83,6 +83,14 @@ void test_sensor_failure_wind()
     SG_CHECK_EQUAL_EP2(m1.getWindSpeed_kt(), -1, TEST_EPSILON);
 }
 
+void test_wind_unit_not_specified()
+{
+    SGMetar m1("2020/10/23 11:58 KLSV 231158Z 05010G14 10SM CLR 16/M04 A2992 RMK SLPNO WND DATA ESTMD ALSTG/SLP ESTMD 10320 20124 5//// $");
+    SG_CHECK_EQUAL(m1.getWindDir(), 50);
+    SG_CHECK_EQUAL_EP2(m1.getWindSpeed_kt(), 10.0, TEST_EPSILON);
+    SG_CHECK_EQUAL_EP2(m1.getGustSpeed_kt(), 14.0, TEST_EPSILON);
+}
+
 int main(int argc, char* argv[])
 {
     try {
@@ -90,6 +98,7 @@ int main(int argc, char* argv[])
         test_sensor_failure_weather();
         test_sensor_failure_cloud();
         test_sensor_failure_wind();
+        test_wind_unit_not_specified();
     } catch (sg_exception& e) {
         cerr << "got exception:" << e.getMessage() << endl;
         return -1;