VERY RARE PHOTO: Aeroflot Yak-40 CCCP-87791 at Montevideo (MVD) in March 1972

Aeroflot Yak-40, CCCP-87791 (c/n 9920203), at Montevideo (MVD) in March 1972, believed to be on the 24th of the month (46 years ago today), during a sales tour visiting several Latin American countries.  Note the derelict C-46 in the background on the left and the 707, believed to be of Pan American, on the right.  (Phil Perry Photo)

Just over 1,000 Yak-40's were built by Russian aircraft manufacturer Yakovlev between 1967 and 1981 with the type being operated mostly by Russian/Soviet airlines and military plus their Soviet bloc allies but with many also seeing service with carriers in Africa, Asia, Latin America (such as Bolivia and Peru) and even a handful flying in western Europe (Greece, Italy and West Germany). 

The Yak-40 had three jet engines and could carry 24-32 passengers over a range of 780nm/1,450km with a full passenger load and 970nm/1,800km with max fuel and had a maximum cruise speed of 297kt/550km.  There were 45 examples reportedly still in service in 2013 with probably a handful still flying today.  It could be considered the very first small regional jet.

As far as the editor knows, there were no Yak-40's sold in Latin America as a direct result of the 1972 sales tour of the region. 

UPDATED 07Apr18:  Carlos Abella has written with more information on the Yak-40's 1972 South American sales tour.  According to the British aviation magazine Flight International, in addition to Argentina, Chile and Uruguay, the Yak-40 visited Bolivia, Brazil, Colombia, Ecuador and Peru with the Soviets claiming that they garnered an order for five examples from Lloyd Aereo Boliviano, although there is no evidence that these were ever delivered. 

Flight International - 07Oct71 - page 2063 

UPDATED 25Mar18:  Good friend Carlos Abella, editor of the excellent Argentine aviation blog Rollout Spotting with exhaustive and detailed coverage of many subjects of interest related to Argentine and Latin American aviation history and current developments, posted this article several years ago with many details about the Aeroflot Yak-40's 1972 South American sales tour:

Rollout Spotting: Aeroflot Yak-40 at Buenos Aires Aeroparque (AEP) on 06Mar72

In summary, the Yak-40 visited both Buenos Aires and Santiago, Chile with the idea of selling the aircraft to airlines of these two countries. 

The then Chilean socialist government of President Salvador Allende was considering adding Russian-built Ilyushin IL-62 long-range jets to the fleet of the government-owned national airline LAN Chile (today's LATAM) given the country's close relationship with the Soviet Union. The Yak-40 was flown to Santiago to pitch this aircraft type too.

Argentina's political situation at the time was not very conducive to increasing commercial ties with the USSR with most business leaders being right-leaning but the English aviation publication Flight International reported that the small regional airline, Aerochaco, based in the northern city of Reconquista, Chaco province ordered two Yak-40's with an option for one more.  However, the Argentine government would not allow the aircraft to operate on the Argentine register due to its not being certificated by the US Federal Aviation Administration.  Also, the Yak's operating economics were apparently poor being small for a jet-powered aircraft with only 24-32 seats.  

A turboprop Antonov 32 was apparently later also demonstrated to the airline but neither type entered service with Aerochaco.  

Aerochaco later went on to operate two Fairchild Hiller FH-227's (stretched model of the Dutch F-27).     

Sources:

https://en.wikipedia.org/wiki/Yakovlev_Yak-40
http://www.airliners.net/aircraft-data/yakovlev-yak-40/386
https://aerospotter.blogspot.com.ar/2013/03/codling-en-aeroparque.html
https://es.wikipedia.org/wiki/Aerochaco