private static void TestMethod() 
        { 
           Plane f16 = new Plane(); 
            Task[] tasks = new Task[5];

            for (int i = 0; i < 5; i++) 
            { 
                tasks[i] = new Task(() => 
               { 
                    for (int j = 0; j < 1000; j++) 
                    { 
                        f16.Altitude += j - 5; 
                    } 
                } 
                ); 
                tasks[i].Start(); 
            }

            Task.WaitAll(tasks);

            Console.WriteLine("[ {0} ]", f16.Altitude); 
        }