Tasmanian Harold Gatty was one of the many pioneers of the golden age of aviation (1927 to 1938). Gatty invented or perfected many of the techniques of aerial navigation. He was the first navigator to circle the earth in an aeroplane in 1931 and he later created a school of navigation for American military aviators. Despite his many accomplishments, he is not widely remembered, but he was a celebrity in his day.

He can take a one-dollar Ingersol watch, a Woolworth compass, and a lantern and at 12 o'clock at night he can tell you just how many miles the American farmer is from the poorhouse. He can look at the Northern Star and a Southern Democrat and tell you if Oklahoma will go Republican, or sane. He knows the Moon like a lobbyist knows the Senators.
- Will Rogers

Early Training

Gatty was born 1903 in Cambelltown, Tasmania. His interest in navigation started in 1917 when he became a cadet midshipman at the Royal Australian Naval College aged 14.

He was discharged from the navy after the end of World War I and signed on to a steamship travelling between Australia and New Zealand. During night watches he studied the stars until he reached the point where he could tell the time by the position of the stars in the various seasons.

Gatty bounced around at sea-related jobs for a while before moving to California in the United States with his wife and six-month old son. There he landed a succession of navigating jobs and eventually opened a school of navigation in Los Angeles.

Initially he focused on marine navigation, but the trans-Pacific flight of Charles 'Smithy' Kingsford-Smith and Charles Ulm, guided by navigator Harry Lyons, piqued Gatty's interest in aerial navigation. Smithy, his co-pilot Ulm and navigator Lyons crossed the Pacific Ocean in 1928. They left Oakland, California on 31 May, 1928 and landed in Sydney on 10 June. They flew from Oakland to Hawaii, then on to Fiji, Suva and Brisbane. Total flying time was eighty-three hours. Gatty recognised the need for formal aerial navigation training for over-water flights where maps and charts are essentially useless.

Aerial Navigation Innovations

Gatty taught students to navigate by sun and stars and drift readings. Two methods of determining 'drift' in his day were dropping smoke flares and using a drift meter. A drift meter is an optical instrument that points at the ground. The more advanced instruments were gyroscopically stabilised. By looking down at terrain or whitecaps, the navigator could determine the amount of drift relative to the airplane's true heading. With a stopwatch and an accurate knowledge of the aircraft's altitude, ground-speed can be determined. After considering the aircraft's true airspeed, wind direction and wind-speed can then be inferred by vector analysis. Gatty accepted flight lessons in exchange if the tuition fees couldn't be paid.

On early over-water flights, the pilots used ships to guide them to their destination. Gatty changed that by inventing a sextant that used a spirit level with a bubble to provide an artificial horizon. He also developed the Gatty Drift Sight which he refined into a good ground speed and drift indicator. This sight was widely used by airmen during the late 1930s and eventually Gatty sold it to the US Army Air Corps. Gatty also perfected a 'double drift' method of taking drift reading headings by flying on courses 90 degrees apart to get accurate ground speeds.

Gatty teamed up with Philip Charles Weems, who taught navigation in his school in San Diego. Weem taught navigation using precalculated position lines called Weems curves. In his book 'Around the World in Eight Days', Gatty describes a Weems curve.

This method obviates the need for mathematical computations in flight, and by means of tables made by Commander Weems after an exhaustive study, greatly simplifies getting a position. He used a 'star-curve' chart in plotting the formulae...

After working with Gatty, Weems declared that Gatty 'has done more practical work on celestial navigation than any other person in the world today.'

In 1930, Charles Lindbergh sent his wife to Gatty for navigation training. Lindbergh was planning a transcontinental dash followed by a flight to Central America with his wife as navigator. Lindbergh also asked Gatty to prepare the route maps and Weems curves for the flights. He referred to Gatty as the Prince of Navigators.

Practical Navigation

LA to New York

In 1929, Roscoe Turner, operations manager for Nevada Airlines, asked Gatty to plan a course for a flight between Los Angeles and New York City. Turner flew, Gatty navigated, and the passenger list included three humans, a turtle, and a lucky teddy bear. They made four refueling stops over 2,520 miles, and despite strong headwinds completed the flight in 19 hours and 53 minutes. This was a new record for a commercial airliner.

Japan to the West Coast?

Next in line to seek Gatty's help was former Royal Flying Corps pilot Harold Bromley who wanted to fly non-stop across the Pacific. After encountering much trouble choosing an aeroplane, an airstrip and a date, the two took off from Sabishiro beach in Japan, on 15 September, 1930. Just over four hours out, in heavy fog, the exhaust collector ring fractured and carbon monoxide began entering the cockpit. Gatty relied on snatched sightings of the sun and moon and dead-reckoning navigation, since they were too heavy to climb above the clouds. After a while the early model Sperry Artificial Horizon broke. Then the wind-driven fuel pump failed, so Gatty spent most of his time operating the emergency hand pump. When Gatty was finally able to get a 'positive fix' on their location he realised that they would not have enough fuel to finish the flight, and he decided they had to turn back to Japan. Under the influence of the carbon monoxide, Bromley was prone to fits of laughter and once put the plane into a steep dive, requiring Gatty to hit him with a spanner and take over the controls until Bromley recovered his senses.

On the way back to Sabishiro, the fuel lines began to leak, so Gatty had to fix them with some friction tape. Bromley was near unconsciousness when they reached land again, so they landed on the first clear stretch of beach. Bromley grabbed a life raft and ran toward the ocean then passed out on the beach. Three days later, Gatty also lost consciousness on a Tokyo street from the delayed effect of the gas. The two failed to find further sponsors and left the plane behind in Japan.

Around the World in Eight Days

The one-eyed pilot, Wiley Post, set many records. The most interesting is an altitude record of 55,000 feet, in the Winnie Mae, after designing the first pressure suit to keep his blood from boiling. Post picked Gatty to be the navigator of his small monoplane for his first globe-circling flight in 1931. They couldn't find a route around the equator that had enough landing and refueling spots, so they had to choose a shorter route at northern latitudes, which covered about 16,000 miles. Prior to that time the record was held by the dirigible Graf Zeppelin which had made a 21-day flight in 1929. Gatty and Post touched down in Newfoundland, England, Germany, Russia, Alaska and Canada before returning to the starting point in New York eight days later. Wiley Post was later killed with Will Rogers in an aeroplane crash near Point Barrow, Alaska.

Amelia Earhart and her navigator Fred Noonan attempted to circle the globe at the equator six years later in 1937. The American military had then opened a primitive base and airstrip on Howland island. Ironically, navigators who fail in a spectacular manner are often much better remembered than those who succeed. Another example is navigator Vice-Admiral William Bligh, who managed to fail in most of his assignments though simple abrasiveness and poor leadership skills.

Gatty and Post took off from Roosevelt Field on Long Island, NY on 23 June, 1931, and made it to Newfoundland in less than seven hours. As they refuelled the plane, Gatty realised that he'd come unprepared: he had only $1 for his lunch, while Post had a grand total of $28 for his own food expenses for the trip.

They made the crossing to England in record time of 16 hours and 17 minutes, and landed at the RAF Sealand base near Liverpool. That same day they flew on to Berlin. There they took a nine-hour break to sleep.

The flight to Moscow was made through heavy headwinds and rain. Post later said they could never have completed that leg had they not had blind-flying instruments. Moscow's October Airport was deserted when they landed, but they were subsequently invited to a banquet in their honour and got only two hours of sleep. At the next stop in Siberia they needed to have the plane towed out of the mud.

Storms over the Bering Sea forced them to fly directly above the waves. Then landing on Solomon beach they bent the propeller. Post straightened it out with a hammer, a wrench, and a flat stone. When Gatty was priming the engine it backfired and propeller whacked him on the shoulder. They flew to Fairbanks to get a new propeller.

They landed again in another sea of mud in Edmonton, Canada, and were greeted then by newsmen:

'Say something', beseeched radio reporters.

'I'm tired of sitting down', grunted Post.

'We're tired, and we're dirty and not much to look at anyway', added Gatty.

Afraid of getting stuck in the mud of Edmonton's airfield, the two took off the next morning from a paved street after officials removed the telephone poles lining the street. That same day, after eight days, 15 hours, and 51 minutes, they touched down in Roosevelt field and received a ticker-tape parade.

Your successful world girdling flight is a striking contribution to aeronautical progress. It is dramatic testimony to the efficiency and reliability of American aircraft. It demonstrates vividly how modern science is making neighbours of all the nations of the world. All America is proud of you in the hour of your extraordinary success. You have enhanced faith in the art of flying and the science of air navigation. I congratulate you most heartily on your achievement. I look forward with pleasure to seeing you at the White House next Monday.
- President Herbert Hoover

The next year, after congress passed a bill allowing the Distinguished Flying Cross to be awarded to civilians for special aviation achievements, Herbert Hoover pinned the medal on the twosome. Gatty was also given immediate US Citizenship so that he could get the specially created post of Senior Aerial Navigation Engineer for the US Air Force. When Gatty turned down the citizenship, saying he'd rather stay Australian, thank you, Congress passed an act that allowed a foreigner to hold the position.

Post and Gatty received their Distinguished Flying Crosses on 18 August, 1932.

Training the US Military

In 1932 Gatty set up navigator schools for the Army where he trained Curtis Lemay and others in celestial navigation, a skill Lemay used to direct and co-ordinate bombing missions from England for the Eighth Air Force and later in Japan and Vietnam.

For his military schools, Gatty emphasised:

• Dead reckoning - Dead reckoning was a simple concept. You leave New York and fly due East at a ground-speed of 200 nautical mile per hour. You expect no winds aloft. You fly five hours. Now put a dot on your chart indicating where you think you are.

• Keeping a log - Gatty's log on the Winnie Mae had the following column headings; Date, Time (GMT), Position or Locality, TC (true course), MC (magnetic course), Ground Speed, Altitude, RPM, Air Temp, Oil Temp, Head Temp, Airspeed, Wind, Drift and Remarks.

• Use of the drift meter.

• Use of the sextant - The sextant is an optical device used to measure the altitude of a celestial body relative to the observer. This allows the navigator to obtain a 'line of position'. In the 1930s the standard error of an observation was about 15 nautical miles. Compare this with an expected error of five metres for a today's hand-held GPS. Air navigation sextants require an 'artificial horizon'. Gatty's solution to this problem was to incorporate a spirit level bubble into the sextant.

• Use of the pelorus - Use of the pelorus to obtain sight bearings on two or more mapped objects. The point where the bearings cross is the observer's position. These went out of use after WWII due to the introduction of short-range, high-frequency devices that provide accurate bearings to aviators (the VOR and TACAN systems).

• Using a temperature sensing device - Using a temperature sensing device to obtain an accurate true airspeed. The aviator must know altitude and air temperature to compute pressure altitude. With a correct pressure altitude, the aircraft's airspeed indicator can be corrected to obtain the true airspeed.

Service with Pan Am

Pan Am hired Gatty to organise an island-hopping trans-Pacific air service route for them. Gatty collaborated with Pan Am chief navigator, Fred Noonan, to establish the navigation procedures for Pan Am Clipper flying boats.

Howard Hughes, wanting to attempt an around-the-world record flight, invited Gatty along, but Gatty decided to stick with Pan Am for then, and recommended his students instead.

Gatty was also approached by a man with an offer for a job with a prominent American air-race pilot. He refused when he learned that the pilot was Jacqueline Cochran. Was this a decision born of chauvinism? Probably not. Cochran was the American queen bee of aviation. One of the first female pilots to race, the first woman pilot to win a race and later, the first supersonic woman pilot. Chuck Yeager, in his autobiography, mentions that he was detailed to certify Cochran in the F-86 Sabre for her supersonic venture. Yeager also mentions that her arrogance once caused her expulsion from a sovereign nation. The fact that Gatty was recommended to Cochran was a tribute to his skill. The fact that he declined may be a testament of his self-respect.

Later Life

During World War II Gatty returned to Australia as an Australian Air Force group captain. In 1943 he resigned and returned to Washington. He wrote a book for the US Navy to help downed navy airmen survive and navigate their life rafts. It was called 'The Raft Book' and was placed in the survival kits of all allied airmen over the pacific.

After the war, Gatty moved to Fiji with his second wife where he set up the Fiji Airways airline and wrote Nature is Your Guide, a book on navigation. It was published after his death by stroke in 1957 aged 54.