Lost in the fog: Sacadura Cabral's last flight, 15 November 1924

On Saturday 15 November 1924 the weather over the Netherlands was too poor for the three Portuguese seaplanes to fly as a group. So they left Amsterdam one after the other, at short intervals, for the first leg of a delivery flight to Lisbon by way of the French coast.2 sources2 sources

They were new Fokker monoplanes on floats, paid for by public subscriptions in Portugal and Brazil. Lieutenant Santos Mota flew one and Lieutenant Pedro Rosado another. The third, numbered 4146, carried Commander Artur de Sacadura Freire Cabral, aged 43 and the most famous airman in Portugal, with his mechanic, Corporal Pinto Correia.3 sources3 sources

Soon after take-off a dense fog closed in and the aircraft lost contact with one another. Santos Mota came down at Brest, in Brittany, and Rosado at Cherbourg, in Normandy. They waited the agreed time for their commander, and when he did not come they alerted the French and British authorities.2 sources2 sources

Sacadura Cabral never arrived. Neither he nor Pinto Correia was seen again.2 sources2 sources

Two and a half years earlier he and the navigator Gago Coutinho had flown from Lisbon to Rio de Janeiro, the first crossing of the South Atlantic by air. The flight had made them heroes in Portugal and Brazil. The man the country now searched the sea for had spent most of the time since trying to make a longer flight still.3 sources3 sources

Sacadura Cabral was born in Celorico da Beira, near the Serra da Estrela in central Portugal, on 23 May 1881. He entered the Escola Naval, the naval academy, in November 1897 at the age of 16 and finished first in his class. In 1901 he sailed as a midshipman in the cruiser São Gabriel for Mozambique.3 sources3 sources

In Mozambique, in 1907, he began working with the officer who would share his fame. Carlos Viegas Gago Coutinho, born in Lisbon in 1869, was a naval officer and field geographer who spent years marking colonial borders. Until 1910 the two men laid out the geodetic survey network of Mozambique from Ponta do Ouro to Bazaruto, and in 1912 they worked together again on the Barotze border in Angola.2 sources2 sources

In August 1915, aged 34, Sacadura Cabral was one of eleven officers accepted for military pilot training abroad, and he was sent to the French army flying school at Chartres. He passed his last test on 9 March 1916, rated a “très bon pilote”, and then specialised in seaplanes. (One Navy web page dates the test to 1915, which does not fit the course dates.) Back in Portugal, he helped found the army flying school at Vila Nova da Rainha as its director of instruction.4 sources4 sources

Portugal had entered the First World War, and German submarines were attacking its ports and ships. In January 1917 Sacadura Cabral proposed aerial patrols of the coast to the Navy Minister. Two FBA seaplanes, an Anglo-French design that he had suggested buying while still in France, went into service early that year. The Navy dates the start of Portuguese naval aviation from them, and he remained its driving force until his death.3 sources3 sources

The North Atlantic was crossed by air in May 1919, by the American flying boat NC-4, which flew in stages from New York to Plymouth by way of Lisbon. Sacadura Cabral was in the party that welcomed its commander, Albert Read, in Lisbon. The Americans had 68 ships posted along the route to guide them and pick them up if they came down. In June that year Alcock and Brown flew non-stop from Newfoundland to Ireland.1 source1 source

That June Brazil's president-elect, Epitácio Pessoa, visited Lisbon. Sacadura Cabral proposed to mark the centenary of Brazil's independence, in 1922, with a flight from Lisbon to Rio de Janeiro. The government authorised it that month. Unlike the Americans, the Portuguese would have no chain of ships marking the route and no radio on board.4 sources4 sources

That made navigation the problem. Over open sea, a navigator fixes his position by measuring the height of the sun or a star above the horizon with a sextant. From an aircraft the sea horizon is often hidden by haze or cloud, and its apparent height changes with altitude.2 sources2 sources

Gago Coutinho fitted a marine sextant with an artificial horizon: a bubble level, of the kind builders use, seen through an extra mirror. He called it a “precision astrolabe”, and Jorge de Castilho later added an electric lamp to light the bubble for night observations. With Sacadura Cabral he also devised a “course corrector”, a plotting board that worked out how far the wind was pushing the aircraft off its course.4 sources4 sources

To measure that drift, the pilot dropped to about 30 metres and the navigator threw smoke buoys of calcium phosphide, which caught fire when they hit the water and gave a fixed mark to sight on. The rest of the time they cruised at 200 to 300 metres.1 source1 source

They tested the method on 22 March 1921, when a Felixstowe F.3 flying boat left the Bom Sucesso naval air station in Lisbon at 10.25 in the morning for Funchal, in Madeira. Sacadura Cabral was pilot and commander, Gago Coutinho navigator, Ortins de Bettencourt second pilot and Roger Soubiran mechanic. They covered about 530 miles in seven and a half hours, or 7 hours 40 minutes by another account, and the Navy judged the navigation system proven.3 sources3 sources

For the long flight Sacadura Cabral chose a seaplane, because there were no airfields in Cape Verde or on the Brazilian island of Fernando de Noronha, and a single engine, because money was short. Fairey, in England, already had plans for a modified IIID with the Rolls-Royce engine he trusted. The aircraft, serial F 400, reached Lisbon in crates in January 1922, and he returned from England on 6 March.2 sources2 sources

The Fairey left the Tagus at about seven in the morning of 30 March 1922, its wings extended and its fuselage stretched to carry extra fuel. It reached Las Palmas, in the Canary Islands, eight and a half hours later. The crew soon found the engine was burning more fuel than planned.3 sources3 sources

Storms held them in the Canaries and then at São Vicente, in Cape Verde, until 17 April. From Praia, on the island of Santiago, the sea was too rough to take off with full tanks, and Sacadura Cabral knew he could not reach Fernando de Noronha. He asked for the cruiser República to wait at the Saint Peter and Saint Paul Rocks, a cluster of bare islets in mid-ocean, so he could land there and refuel. By then the government had named the aircraft Lusitânia.3 sources3 sources

The leg of 18 April, 908 nautical miles, was the longest of the trip and took 11 hours and 21 minutes. The rocks were a speck in the ocean, and the aircraft would reach them at the limit of its fuel.2 sources2 sources

Gago Coutinho's sums were right, and the rocks appeared where he said they would, at about five in the afternoon. But the sea was heavy. As Sacadura Cabral landed, a wave broke one of the floats and the Lusitânia tipped nose-first into the water. The República's crew pulled the two men out, with their instruments, and the aircraft sank.2 sources2 sources

The Portuguese press followed every detail, and public opinion pressed the government to let the airmen carry on. On 27 April parliament promoted both men by distinction, and the government shipped a second Fairey, number 16, to Fernando de Noronha on the Brazilian ship Bagé. It arrived on 6 May. On 11 May the airmen flew back towards the rocks to close the gap in their route, but bad weather turned them round, and on the way back the engine failed and they came down on the open sea.3 sources3 sources

They drifted for about nine hours, into the night, until a British cargo ship that happened to be off its usual route found them. The República salvaged only the engine. Portugal sent the last Fairey its naval aviation had, number 17, on the cruiser Carvalho Araújo, and it reached Fernando de Noronha on 2 June.3 sources3 sources

On 5 June they flew the 300 miles to Recife in four and a half hours. A reporter there asked Sacadura Cabral what had gone through his head to make such a journey.2 sources2 sources

From Recife they hopped down the coast to Salvador, Porto Seguro and Vitória, cheered at every stop by Brazilians and by Portuguese living in Brazil. On 17 June 1922 they landed in Guanabara Bay at Rio de Janeiro. The wife of President Epitácio Pessoa named the aircraft Santa Cruz, and it stayed on show for almost a year at Rio's International Exposition.3 sources3 sources

The totals vary with the source. The Navy and the Biblioteca Nacional give 4,527 miles in 62 hours and 26 minutes of flying; Pesquisa FAPESP gives the same flying time and 8,383 kilometres, which is 4,527 nautical miles, though it counts them only as far as Recife. The Revista da Armada gives 4,367 miles in about 60 hours, and the 2022 CTT stamp leaflet 4,367 miles in 60 hours and 14 minutes, of which 36 hours and 29 minutes were over open ocean with nothing below to steer by. The whole journey took 79 days.6 sources6 sources

The two airmen toured Brazil and then Portugal. Lisbon gave them a huge welcome on 27 October 1922. Sacadura Cabral received honorary doctorates from the universities of Lisbon and Porto, and the colonial government of São Tomé renamed the Ilhéu das Rolas after Gago Coutinho and the channel beside it after Sacadura Cabral.3 sources3 sources

Sacadura Cabral wanted more. In April 1923 he gave the Navy Minister a detailed plan for a flight around the world, to start in March 1924. With money from public subscriptions in Portugal and Brazil he ordered five Fokker aircraft in the Netherlands, four with 380-horsepower Rolls-Royce Eagle IX engines and one with a 450-horsepower Napier Lion. Neves and his co-authors give 360 and 460 horsepower.3 sources3 sources

Parliament argued for months over the support ships he wanted, and the date passed. On 28 September 1924 American army airmen completed the first flight around the world instead. Sacadura Cabral had also clashed with the government over money for naval aviation and asked to resign his commission in February 1923; the request was turned down a year later.2 sources2 sources

He did not give up on the Fokkers. On 12 July 1924 he went to the Netherlands to take delivery, and on 30 August he flew the first one, fitted with wheels, to Amadora, outside Lisbon. On 28 October he went back for three more, this time seaplanes. They were ready to leave on 15 November.1 source1 source

Once the alarm was raised, French and British bases and the ships in the area were told to look out for the missing seaplane. For several days nothing was found.2 sources2 sources

Then a Belgian fishing boat, on its way home to Ostend, reported that it had picked up wreckage in the English Channel: pieces of a float with an aircraft number engraved on it. The Revista da Armada says this was three days after the flight and the Navy's library says four. Fernando Neves, Jorge Barata and André Silva, researchers at the Universidade da Beira Interior, date the find to 18 November and place it at 50°37'N, 1°10'E, in the eastern part of the Channel.3 sources3 sources

The news that reached the papers was confused. A despatch from Rotterdam on 19 November said fishing boats had found a seaplane identified as his, with no trace of a body. From Lisbon the next day came a report that his body had washed up on a beach near Ostend. It was never confirmed, and the Navy says only that the hope of finding the men grew ever smaller.3 sources3 sources

Nobody knows what brought the Fokker down. The float fragments suggest it ended in the sea, but no one saw it go, and neither body was ever recovered. Portugal declared national mourning on 15 December 1924, and on 6 January 1925 Sacadura Cabral was officially declared missing.3 sources3 sources

Sacadura Cabral had walked away from seven aircraft accidents, and he once told a friend he would die like everybody else, in his bed. The Brazilian aviation pioneer Alberto Santos-Dumont, who had been photographed with the two airmen in Brazil, wrote to Gago Coutinho from Biarritz, in France, eight days after the flight.2 sources2 sources

In 1925 he received a posthumous official commendation for his work as director of naval aeronautics and for the mission in Fokker 4146 that ended in his disappearance. Towns in Portugal and its former colonies named villages, streets and avenues after him.1 source1 source

Gago Coutinho lived another 34 years. By 1927 the German instrument maker Plath was building an improved version of his sextant with the Portuguese Navy's permission, and in the early 1930s he flew to South America as co-navigator of the giant Dornier Do X flying boat, using the instrument. He was made a full admiral in 1958 and died in Lisbon in 1959, aged 90.2 sources2 sources

In July 2024, the centenary of his disappearance, President Marcelo Rebelo de Sousa approved Sacadura Cabral's promotion by distinction to rear admiral. The Navy's statement said that had he not disappeared, promotion to admiral's rank would have come naturally.1 source1 source