Although the Transoceanic Flights had already piqued the state's attention, the airplane's lack of aerial navigation equipment rendered it unsuitable for this new trend in 1919. Three years later, in 1922, Sacadura Cabral and Gago Coutinho conducted a Transoceanic Flight to demonstrate the autonomy and usefulness of the Sextant with an artificial horizon, in combination with novel air navigation instruments, all handled by a simplified short air navigation method. Unfortunately, due to errors induced by the vertical dynamics associated with the aircraft's speed, the sextant was constantly adjusted to the sea horizon rather than the perfect readings of the artificial horizon. This condition required a search for a suitably clear horizon line, forcing the seaplane's altitude to be often lowered. Furthermore, a few
supplementary navigation devices risked their initial autonomous air navigation. Nonetheless, by measuring the size of the wingspan shadow reflected on the ocean's surface, the pilots managed to adjust their expertise to maintain the seaplane on the planned trajectory.
Furthermore, this novel and reliable steering method allowed them to perform trigonometric calculations to estimate their height, which was critical in calculating the aircraft's positioning. Thus, the Journey was recognized as a significant milestone in aviation history, ushering the
use of the sextant as a key means of air navigation and proving the effectiveness of a revolutionary principle of Coutinho's short methods, never before documented on Astronavigation. Along with the First Transoceanic Flight with Autonomous Aerial Navigation, one of the itineraries featured an 11 ½ hour crossing the Atlantic from Cape Verde
to St. Peter and St. Paul Rocks. When it is remembered that they managed to reach this remote and a pretty small destination (a few hundred ft. long and the highest point 60 ft. above the water) after a flight of nearly 900 nautical miles over the Ocean, it exalts the remarkable feat of the airmen.