всё готово

Stormtrooper/Stormtrooper/AirDelegate.cs

@@ -0,0 +1,10 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Stormtrooper
+{
+    public delegate void AirDelegate(DrawningMilitaryAirplane airplane);
+}

Stormtrooper/Stormtrooper/FormAirConfig.Designer.cs

@@ -334,6 +334,7 @@
             this.buttonAdd.TabIndex = 3;
             this.buttonAdd.Text = "Добавить";
             this.buttonAdd.UseVisualStyleBackColor = true;
+            this.buttonAdd.Click += new System.EventHandler(this.buttonAdd_Click);
             // 
             // buttonCancel
             // 

Stormtrooper/Stormtrooper/FormAirConfig.cs

@@ -13,6 +13,7 @@ namespace Stormtrooper
     public partial class FormAirConfig : Form
     {
         DrawningMilitaryAirplane _airplane = null;
+        private event AirDelegate EventAddAirplane;
         public FormAirConfig()
         {
             InitializeComponent();
@@ -24,6 +25,7 @@ namespace Stormtrooper
             panelCyan.MouseDown += PanelColor_MouseDown;
             panelYellow.MouseDown += PanelColor_MouseDown;
             panelBlue.MouseDown += PanelColor_MouseDown;
+            buttonCancel.Click += (object sender, EventArgs e) => Close();
         }
 
         private void DrawAirplane()
@@ -34,6 +36,17 @@ namespace Stormtrooper
             _airplane?.DrawAirplane(gr);
             pictureBoxShow.Image = bmp;
         }
+        public void AddEvent(AirDelegate ev)
+        {
+            if (EventAddAirplane == null)
+            {
+                EventAddAirplane = new AirDelegate(ev);
+            }
+            else
+            {
+                EventAddAirplane += ev;
+            }
+        }
 
         private void label_MouseDown(object sender, MouseEventArgs e)
         {
@@ -118,5 +131,11 @@ namespace Stormtrooper
             }
             
         }
+
+        private void buttonAdd_Click(object sender, EventArgs e)
+        {
+            EventAddAirplane?.Invoke(_airplane);
+            Close();
+        }
     }
 }

Stormtrooper/Stormtrooper/FormMapWithSetAirplane.cs

@@ -78,32 +78,26 @@ namespace Stormtrooper
         /// <param name="sender"></param>
         /// <param name="e"></param>
         private void ButtonAdd_Click(object sender, EventArgs e)
+        {
+            var formLocomotiveConfig = new FormAirConfig();
+            formLocomotiveConfig.AddEvent(AddLocomotive);
+            formLocomotiveConfig.Show();
+        }
+        private void AddLocomotive(DrawningMilitaryAirplane drawningMilitaryAirplane)
         {
             if (listBoxMap.SelectedIndex == -1)
             {
                 return;
             }
-            MainForm form = new();
+            DrawningObject airplane = new(drawningMilitaryAirplane);
-            if (form.ShowDialog() == DialogResult.OK)
+            if (_mapCollection[listBoxMap.SelectedItem?.ToString() ?? string.Empty] + airplane != -1)
             {
-                if(form.SelectedAirplane != null)
+                MessageBox.Show("Объект добавлен");
-                {
+                pictureBox.Image = _mapCollection[listBoxMap.SelectedItem?.ToString() ?? string.Empty].ShowSet();
-                    DrawningObject airplane = new (form.SelectedAirplane);
+            }
-                    if (_mapCollection[listBoxMap.SelectedItem?.ToString() ?? string.Empty] + airplane != -1)
+            else
-                    {
+            {
-                        MessageBox.Show("Объект добавлен");
+                MessageBox.Show("Не удалось добавить объект");
-                        pictureBox.Image = _mapCollection[listBoxMap.SelectedItem?.ToString() ?? string.Empty].ShowSet();
-                    }
-                    else
-                    {
-                        MessageBox.Show("Не удалось добавить объект");
-                    }
-                }
-                else
-                {
-                    MessageBox.Show("Объект не создан");
-                }
-                
             }
         }
         /// <summary>

Stormtrooper/Stormtrooper/Program.cs

@@ -16,7 +16,7 @@ namespace Stormtrooper
         {
             Application.EnableVisualStyles();
             Application.SetCompatibleTextRenderingDefault(false);
-            Application.Run(new FormAirConfig());
+            Application.Run(new FormMapWithSetAirplane());
         }
     }
 }