Even Lindbergh Got Lost
In the 1920’s, only one man held the key to aerial navigation.
- By Roger Connor
- Air & Space magazine, February 2013
Photo by Hugh Talman, Smithsonian National Museum of American History
(Page 2 of 3)
Several weeks later, after donating the Spirit to the Smithsonian Institution, Lindbergh decided he would set out from Washington for Detroit to finalize his plans with Ford and Lanphier. He felt the trip would be an ideal time to learn “avigation”—a popular term used in the 1920s and ’30s to differentiate air navigation from maritime practice—and asked polar explorer Lincoln Ellsworth for suitable tutors. Ellsworth recommended Weems.
Shortly after Roald Amundsen’s 1925 Arctic flight, in which the crew was nearly lost after a crash-landing, Ellsworth had begun looking in earnest for better aerial navigation techniques. At the time, Weems was an instructor at the Naval Academy in Annapolis, and though not a pilot, he found the problem of using celestial navigation in airplanes to be an interesting intellectual challenge. His conservative Navy superiors disagreed and rejected his request for funding to develop a simplified system. Weems’ ideas so impressed Ellsworth, however, that he helped finance the research.
Lindbergh petitioned the White House for Weems to be assigned as navigation tutor, and the Navy officer received a leave of absence, to the irritation of his superiors. He told Lindbergh later, “My relations with the Navy Department [have] been rather peculiar. I get patted on the back by one crowd and kicked in the pants by another!”
Not surprisingly, most Americans assumed Lindbergh was an expert in all things aeronautic, and learning that he needed training in navigation left many reporters confused. When Lindbergh began his training with Weems, the New York Times wrote, “It will be news to…millions that Colonel Lindbergh needs to be taught navigation…. If the Colonel doesn’t know how to navigate, who knows anything about anything?” But the publicity started a conversation in the aviation community, one thoroughly documented by the newspapers of the time, about the poor state of air navigation and the potential for celestial navigation to be a solution on long over-water flights.
Weems approached Lindbergh’s training with items from his bag of tricks, including his hack watch. Previous chronometers could be set only to the minute; this was an acceptable error for 19th century mariners who might go weeks or more before stopping and making an adjustment, but not for 20th century pilots who could use radio broadcasts to synchronize their timepieces. A watch error of 30 seconds could throw off a position calculation as much as seven miles, so Weems’ innovation was significant.
Weems used most of the lessons to teach Lindbergh how to find his position by shooting the sun with a very rare sextant. It was a 1924 Bausch & Lomb model, of which only six were made, and Weems believed it was still the best model available in the United States. Bubble sextants had been around for more than a decade, but because so little attention had been paid to aerial navigation, their design had not advanced much. During his sessions with Lindbergh, Weems carefully studied the sextant’s deficiencies, later taking his notes to the National Bureau of Standards, which worked with Bausch & Lomb to produce an improved version that saw wide service in the 1930s.
Another Weems innovation used in Lindbergh’s training was the Star Altitude Curves, a revolutionary set of charts that let a navigator find his position using two stars (one was usually the North Star, Polaris). The graphs helped cut the calculation time from 15 minutes to 40 seconds. During the day, instead of triangulating position using two stars, a navigator could use the sun to determine a line of position. By measuring the angle between the horizon and the location of the sun on its daily path, a navigator could draw a line on the globe and be assured that his position was a point somewhere on that line.
In Line of Position, Weems published the ultimate Cliffs Notes for this more difficult calculation. Though Lindbergh had dropped out of college to fly, he proved to be an excellent student and “toiled cheerfully for days over head-splitting mathematics,” Weems noted in a letter to a friend. “Lindbergh makes a fine student. He [studies] till twelve or one o’clock and does not get ‘fussed’ or rushed.” During a visit to New York, Weems stayed with Lindbergh to spend extra time tutoring, but found that he “didn’t really do much instructing”; the pilot “was brilliant and caught on quickly. He instructed himself.”
Weems and Lindbergh took a series of flights together in May 1928 in a Ryan Brougham given to the pilot by Benjamin Franklin Mahoney, owner of Ryan Airlines (the San Diego company that built the Spirit). The first flight was from Bolling Field in Washington, D.C., to Long Island’s Curtiss Field. Even with Weems’ innovations, celestially navigating while flying was a two-person job. Weems did the calculations, though he noted, “Lindbergh flew his ship with one hand and took a sextant altitude of the sun with the other! I am confident that this was the first time in history such a thing had ever been done.” But Weems’ system was still a work in progress: He noted that Lindbergh’s accuracy in this walking-and-chewing-gum mode could be off by as much as 15 or 20 miles. Shooting the sun next to the pilot, however, Weems was eventually able to fix position to an accuracy of three miles—a margin of error unacceptable today, but the position was certainly good enough to put a pilot within sight of an island.
After stopping in New York, the pair headed to Detroit to meet Henry Ford. Although Lindbergh never made the around-the-world flight, his lessons were not in vain. He helped establish cross-country air routes for Transcontinental Air Transport (known as the “Lindbergh Line” and later as TWA), and was also courted by Juan Trippe of Pan American Airways to establish transatlantic air routes. Because the continental United States was covered by a network of radio beacons, celestial navigation had little application there, but the method became essential for the overseas routes that Trippe was eyeing.
Lindbergh was a remarkably good sport about the publicity over his shortfall in navigational knowledge, and was willing to have Weems draw attention to it—even allowing his Paris navigation to be described as “little more than the automobile tourist” following street signs. The press coverage of Lindbergh’s lessons, along with his ringing endorsement, allowed Weems to launch an aerial navigation consulting business while he was still serving at sea aboard a Navy oiler. The two men kept up a close exchange on navigational questions over the next decade, including collaborating on a variant of the Second-Setting watch, which converted time to arc, the 360 units in which the globe is marked. The improved Lindbergh Hour Angle watch, as it was marketed, helped speed up one of the many calculations with which a navigator was tasked.
With Lindbergh as its first disciple, the Weems System of Navigation quickly attracted a broad range of aviators who were eager to learn the latest techniques. Armed with a set of tools, including the bubble sextant, the Second-Setting watch, and celestial plotting forms for making calculations from the Star Altitude Curves and Line of Position books (and by the mid-1930s, an Air Almanac, Lunar Ephemeris for Aviators, and a Mark II plotter—which every student pilot still receives today), Weems’ pupils now had everything they needed to find their position while in flight. One of the first clients was Australian navigator Harold Gatty, whom Weems quickly hired as chief instructor at his new school in San Diego, California, the first dedicated to air navigation. The two collaborated on numerous advances in navigation, including the Gatty Drift Meter, used to measure an aircraft’s drift from a track. Gatty taught Anne Morrow Lindbergh the Weems system. When Charles Lindbergh took Trippe up on his offer and began planning overseas survey flights for Pan American in a Lockheed Sirius, he realized that his wife Anne would have to assist with navigation. Gatty proved to be an excellent instructor. Lindbergh wrote to Weems that “we used one of your sextants and a great deal from your System of Navigation on our last transcontinental trip [April 1930]. Mrs. Lindbergh took all of the sextant readings in addition to working them out and doing most of the navigation.”