Air navigation,

Philip Van Horn Weems (March 29, 1889 - June 2, 1979) was a United States Navy officer, inventor of navigational instruments and methods, including the Weems Plotter and the Second Setting Watch and author of navigational textbooks. Officer, and inventor of navigational instruments and methods, including the Weems Plotter and the Second Setting Watch and author of navigational textbooks. Weems and his wife established the Weems School of Navigation in 1927. After Charles Lindbergh completed his celebrated solo flight across the Atlantic Ocean, the Navy assigned Weems to teach him celestial navigation for a month in 1928. Fred Noonan, Amelia Earhart's navigator on her last flight, considered him his mentor After his first retirement, Weems wrote several books; Air Navigation (1931) was particularly well received, and was awarded a gold medal by the Aero Club of France. In 1935, he patented the Mark II Plotter, another invention was the Second Setting Watch. According to the Institute of Navigation, however, "his proudest achievement" was the Star Altitude Curves, which simplified finding one's position; it was adopted by the Army Air Corps prior to World War II.