Traffickers frequently use airplanes to shuttle drugs and drug components around South America, and governments there have struggled to stop them.
Drug traffickers in South America are making heavy use of clandestine flights to move drugs around the continent, and while authorities can detect them, their ability to stop them is still limited.
An average of 40 illegal flights a month arrive in Argentina from Bolivia and are detected by radar located around the northern Argentine city of Tartagal.
According to intelligence reports cited by Argentina newspaper La Nacion, those flights are each capable of carrying 400 to 500 kilograms of cocaine, amounting to 20 tons of cocaine arriving in the country a month.
Once in Argentina, those drugs — whether they are cocaine, coca base, marijuana, or other substances like precursor chemicals for synthetic drugs — are transported for local distribution among Argentina's large domestic drug market or shipped on to points in Africa or Europe.
Previous reports from the Argentine military claimed that about 120 flights arrive and depart the South American country each day, bringing about 80% of the illicit drugs that are transported into the country.
Peru and Bolivia, major drug producers that share a border and are just north of Argentina, are also dotted with makeshift runways that have helped support an air bridge connecting the drug-production and shipment zones in South America.
The remoteness of the areas involved and logistical limitations like a lack of radar coverage have hindered efforts to crack down on such flights.
According to a report the Anti-Drug Associate of Argentina released this summer and cited by Insight Crime, those flights make use of some 1,500 clandestine airstrips in the country.
"There is no province (in the north) that doesn't have at least 60 airstrips," said Claudio Izaguirre, the organization's head.
These airstrips have helped make Argentina into a major transshipment point for illegal narcotics. In addition to cocaine traversing the country bound for Europe and other destinations, Argentina itself has become a hub for precursor chemicals used in the production of synthetic drugs.
Criminal organizations in Argentina have partnered with groups like Mexico's Sinaloa cartel to move precursor chemicals, and air transport has become a common way to move drug cargoes, particularly in the skies over Central America.
Despite the awareness of such air traffic over southern South America, the Argentine government and others in the region have had little success shutting down the activity.
Argentina, where President Mauricio Macri recently reauthorized a controversial shoot-down policy, has begun looking to upgrade and expand its fighter and interceptor aircraft and train pilots to fly them.
Like Peru and Bolivia, Argentina has also worked to eliminate clandestine airstrips. That effort has been challenged by the relative ease with which such airstrips can be rebuilt and by traffickers who can move drugs by air without actually landing, using methods such as airdrops.