Made the Sunrise and sunset times correct for British Summer time.

myFlightInfo/Form1.cs

@@ -215,7 +215,7 @@ private void btn_reset_Click(object sender, EventArgs e)
                 lbl_d_airport_name.Text = "";
                 lbl_to_pressure.Text = "";
 
-                dateTimePicker1.Value = DateTime.Now;
+                NavigationDateTimePicker.Value = DateTime.Now;
 
                 lstbx_navigation_from.Items.Clear();
                 lstbx_navigation_to.Items.Clear();
@@ -245,9 +245,9 @@ private void btn_calculate_altimiter_Click(object sender, EventArgs e)
 
              */
 
-            int year = dateTimePicker1.Value.Year;
-            int month = dateTimePicker1.Value.Month;
-            int day = dateTimePicker1.Value.Day;
+            int year = NavigationDateTimePicker.Value.Year;
+            int month = NavigationDateTimePicker.Value.Month;
+            int day = NavigationDateTimePicker.Value.Day;
             int hour = DateTime.Now.Hour;
             int minute = DateTime.Now.Minute;
             int second = DateTime.Now.Second;
@@ -308,9 +308,9 @@ private void cmbobx_airport_info_SelectedIndexChanged(object sender, EventArgs e
             {
                 grpbx_towns.Visible = false;
 
-                int year = dateTimePicker1.Value.Year;
-                int month = dateTimePicker1.Value.Month;
-                int day = dateTimePicker1.Value.Day;
+                int year = NavigationDateTimePicker.Value.Year;
+                int month = NavigationDateTimePicker.Value.Month;
+                int day = NavigationDateTimePicker.Value.Day;
 
                 //we use flags as the info in the xml file we will use may not be complete
                 //we only show info if it is complete.
@@ -361,9 +361,9 @@ private void dateTimePicker1_ValueChanged(object sender, EventArgs e)
                 ((lbl_d_airport_name.Text != "..") && (lbl_d_airport_name.Text != "")))
             {
 
-                int year = dateTimePicker1.Value.Year;
-                int month = dateTimePicker1.Value.Month;
-                int day = dateTimePicker1.Value.Day;
+                int year = NavigationDateTimePicker.Value.Year;
+                int month = NavigationDateTimePicker.Value.Month;
+                int day = NavigationDateTimePicker.Value.Day;
 
                 Navigate.SolarInfo(lbl_p_airport_name.Text, lstbx_navigation_from, year, month, day);
                 Navigate.SolarInfo(lbl_d_airport_name.Text, lstbx_navigation_to, year, month, day);

myFlightInfo/Navigation/Navigate.cs

@@ -47,6 +47,23 @@ public static void SolarInfo(string airfield, ListBox myListBox, int year, int m
 
                 Sunriset.SunriseSunset(year, month, day, lat, lng, out double tsunrise, out double tsunset);
 
+                //Find last Sunday in March and October of year in datepicker
+                DateTime marchDate = CheckDate.LastSundayOfMonth("3", year.ToString());
+                DateTime octoberDate = CheckDate.LastSundayOfMonth("10", year.ToString());
+                // Construct the chosen date we are looking at 
+                DateTime DateToCheck = DateTime.Parse(day + "/" + month + "/" + year + " 00:00:00");
+
+                //Are we in BritishSummerTime for chosen date? 
+                //We only fly in daylight so no need to worry about the hour.
+                bool BritishSummerTime = marchDate <= DateToCheck && DateToCheck <= octoberDate;
+
+                if (BritishSummerTime)
+                {
+                    tsunrise += 1;
+                    tsunset += 1;
+                }
+
+
                 if (NumItems >= 12)
                 {
                     //If we are updating then delete and add again

myFlightInfo/common_data/BSTorGMT.cs

@@ -0,0 +1,21 @@
+using System;
+
+namespace myFlightInfo.common_data
+{
+    class CheckDate
+    {
+        public static DateTime LastSundayOfMonth(string month, string year)
+        {
+            int myyear = Convert.ToInt32(year);
+            int mymonth = Convert.ToInt32(month);
+            var myDayOfWeek = DayOfWeek.Sunday;
+
+            DateTime date = new DateTime(myyear, mymonth, DateTime.DaysInMonth(myyear, mymonth), System.Globalization.CultureInfo.CurrentCulture.Calendar);
+
+            int daysOffset = date.DayOfWeek - myDayOfWeek;
+            if (daysOffset < 0) daysOffset += 7; // if the code is negative, we need to normalize them
+
+           return DateTime.Parse(date.AddDays(-daysOffset).ToLongDateString());
+        }
+    }
+}

myFlightInfo/myFlightInfo.csproj

@@ -73,6 +73,7 @@
     <Compile Include="AreYouSure.Designer.cs">
       <DependentUpon>AreYouSure.cs</DependentUpon>
     </Compile>
+    <Compile Include="common_data\BSTorGMT.cs" />
     <Compile Include="CrossWind.cs">
       <SubType>Form</SubType>
     </Compile>
@@ -85,7 +86,9 @@
     <Compile Include="compliance_data\aircraftName.Designer.cs">
       <DependentUpon>aircraftName.cs</DependentUpon>
     </Compile>
-    <Compile Include="compliance_data\compliance_data.cs" />
+    <Compile Include="compliance_data\compliance_data.cs">
+      <SubType>Form</SubType>
+    </Compile>
     <Compile Include="crosswind\Crosswind.cs" />
     <Compile Include="Form1.cs">
       <SubType>Form</SubType>