Earth inductor compass

This variation in the generated voltage is measured, allowing the Earth inductor compass to determine direction.The earth inductor compass was first patented by Donald M. Bliss in 1912 and further refined in the 1920s by Paul R. Heyl and Lyman James Briggs of the United States National Bureau of Standards,[3] and in 1924 by Morris Titterington at the Pioneer Instrument Company in Brooklyn, New York.[5] Over the transatlantic leg of his voyage – a distance of about 2,000 miles (3,200 km) – he was able to navigate with a cumulative error of about 10 miles (16 km) in landfall, or about one half of one percent of the distance travelled, by computing his heading at hourly intervals for a dead reckoning estimate of position.Later versions simplified readings to show the offset from the intended heading, rather than the full range of compass directions.The revised design allowed the user to rotate the commutators in such a way that zero current would be produced when the craft was traveling in the intended direction.
The anemometer of the earth inductor compass on the Spirit of St. Louis shows as a small "T" shape above the fuselage behind the wing
compasselectromagnetic inductionEarth's magnetic fieldinduction fieldelectric generatorPaul R. HeylLyman James BriggsUnited States National Bureau of StandardsMorris TitteringtonPioneer Instrument CompanyBrooklyn, New YorkMagellan MedalAmerican Philosophical Societymagnetic compassDouglas World CruisersAround-the-World flightU.S. Army Air CorpsCharles Lindberghtransatlantic flightSpirit of St. Louisheadingdead reckoningarmaturescommutatorsgalvanometersanemometeruniversal jointgyroscopic effectN. MinorskyFlight instrumentsPitot-staticAltimeterAirspeed indicatorMachmeterVariometerGyroscopicAttitude indicatorHeading indicatorHorizontal situation indicatorTurn and slip indicatorTurn coordinatorTurn indicatorAircraft periscopeCourse deviation indicatorInertial navigation systemSatellite navigationAir data inertial reference unitGlass cockpitHead-up displayIntegrated standby instrument systemPrimary flight displayV speedsYaw string