That same year, along with other sailors, he embarked for the United States with the mission of retrieving the monitors Manco Cápac and Atahualpa to Callao, serving on the tug steamers Marañón, Reyes and Pachitea.

On November 7, 1870, with the purpose of completing his studies, he entered as a student at the Naval School and was assigned to the steamer Marañón.

Between June 1878 and April 3, 1879, he was the second commander of the Huáscar, his cousin, Juan Pablo de los Heroes Michelena, was the ironclad captain.

In late July, the Huáscar captured several Chilean vessels, such as the 'Adelaida Rojas, E. Saucy Jack, and Adriana Lucía.

However, the biggest blow occurred on July 23 with the Capture of the steamer Rímac, which was transporting the Carabineros de Yungay [es] squadron which contained horses, weapons, and correspondence.

No, on the contrary, when the melee bugle sounds, and I find myself in the chamber, I climb the slope of Calvary with the greatest tranquility and full of joy, because I know that when I arrive on deck, the country will collect my services.

Peruvian hearts will serve as cobblestones in the streets where you spend in Lima the day you bring us the last victory, wrapped in our national flag.

This shot went through the monitor's chimney and killed Lieutenant De los Heros, completely destroying his body.

They lowered a boat to rescue the remains, but they only found his cap, his scapular of the Heart of Jesus, the heel of one of his boots and fragments of his uniform.

[3] Admiral Miguel Grau expressed his sorrow for this loss in the combat report and in the letter he wrote to his father.

[4] The feeling of pain that the death of the lieutenant provoked among his companions was recorded in a guard book: This bomb blew up our dear and never well-mourned comrade Carlos de los Heros.

With the disappearance of this gentleman, he loses his family, the most dear to her; the companions of him, the true and loyal friend; and the navy of Peru, to one of its most worthy, brave and at the same time, the most modest officers.On September 15, 1879, the funerals were held in Arica.

Members of his family were then motivated to fight in the war due to the death of Carlos de los Heros.

Two of his uncles, Ramón and Ambrosio de los Heros, died in that battle, as did his cousin Francisco Javier Retes.