The surplus US Navy P-3C Orion aircraft will replace the six P-3Bs Argentina received between 1997 and 1999, of which none are operational.
On Sep. 27, 2019, Argentina’s Minister of Defense, Oscar Aguad, announced that the Comando de Aviación Naval (CAN, Argentina Naval Aviation Command) procured four Lockheed P-3C Orion maritime patrol aircraft to replace earlier P-3B models.
As Aguad pointed out while speaking at the “Intereses Argentinos en el Atlántico Sudoccidental” (Argentine Interests on the South Western Atlantic) conference, the four aircraft had been purchased from the US government.
The intention is to replace the six P-3B Orions Argentina received between 1997 and 1999, of which none are operational. As the P-3Bs required major structural refurbishment, it was decided that the best course of action was to replace them with newer aircraft recently retired by the US Navy.
According to Aguad, an option to buy two new Airbus C-295MPAs was studied too. However, as reported by Scramble Magazine, budget restrictions, less aircraft for the money, less aircraft for the mission, the P-3C’s longer endurance and payload, the less extensive training and education needed for current CAN pilots (the swap to P-3C is more easy) and the CAN’s existing experience operating a fleet of Orions, were decisive in the matter.

Talks with the US Government and the US Navy about the four P-3Cs started as early as 2016. The four aircraft are selected from the inventory of the 309th Aerospace Maintenance And Regeneration Group (AMARG). It is expected that first deliveries will take place in 2020.
The P-3C Orion is a land-based, long-range, anti-submarine warfare patrol aircraft. In operation since the 1960s, the Orion is getting replaced by the new Boeing P-8 Poseidon.
The P-3C Update III is Orion’s baseline configuration. It has advanced submarine detection sensors, Magnetic Anomaly Detection equipment and may carry a mixed payload of weapons internally and on wing pylons. The most recent updates deliver modern technology and improved acoustic sensors. Continuing structural engineering and analysis of fatigue data is conducted under the Fatigue Life Management Program (FLMP).
The P-3C Orion signals intelligence variant, the EP-3E Aries, is still in service and performing missions all over the world.

Photo credit: U.S. Navy and Martin.Otero via Wikipedia