Sharpening the Yarara
At the beginning of 1939, the Yarara was starting to get noticed by the aviation world in general. This was due primarily to it now being used by more than just its nation of origin and by it’s complete outperformance of the Curtiss Hawk 75 in the recent and quite unsuccessful attempt to gain a market for the type among the three Yarara using nations.
Examples of the Yarara were given places of prominence by Argentine delegations at San Francisco’s Golden Gate International Exposition and the New York World’s Fair, both of which opened in Spring of that year and performed several attention getting overflights of the grounds of both events. As more military and aviation industry experts got a close look at the machine, the overall feeling was that the Yarara was a high quality and competitive design worthy of further attention.
With a top speed of about 420 kmh and a range of around 1950 km, the Yarara was seen as comparitive performance wise to the Kawasaki Ki-32 which had been introduced in 1938 and generally superior to most other aircraft in the attack and close support class, which the Yarara had been categorised as, of the day.
As good as things seemed for the Yarara, export had shown that there were ways of making it better:
The Argentine built machines retained some of the Garza’s ability to carry camera gear behind the rear crew position. While Uruguayan and Brazilian crews had trained on aircraft of Argentine standard, most of them didn’t see the logic of the camera placement when the space could be used for more fuel or perhaps better radio equipment. Uruguayan aircraft had been ordered built without cameras while the Brazilian aircraft had them removed from the design before production even started. Later production batches for Argentina eventually had the cameras deleted as well.
Weapons delivery accuracy had been increased tremendously since the first Yararas had entered Argentine service; however, torpedo delivery was a nagging shortcoming for the aircraft. A series of accidents in torpedo dropping practices showed that the aircraft was in serious need of more power at the lower altitudes required for successful torpedo attacks.
For the summer of 1939, torpedo operations with the aircraft were suspended until a solution could be found. Hispano-Suiza Argentina was put to work on finding a way to get more power from the 12Y engine or, failing that, develop a new engine.
The ability for German shipping to reach ports in all three countries, the growing certainty of war and the severely degraded relations between the three nations and Germany made the torpedo mission seen as essential in the Yarara’s capabilities, it couldn’t be suspended forever.
With a good deal of experimenting and adjustments, the needed power was found and the Yarara was back to torpedo dropping just in time for the outbreak of WWII in September.
The Rio de la Plata Incident
The German ship, Admiral Graf Spee, had been stalking shipping lanes in the Indian and Atlantic oceans for targets of opportunity since the very outbreak of the war. The Royal Navy had been persuing the ship for most of the autumn and had moved to intercept it at it’s next predicted point of attack; the Rio del la Plata estuary that formed the border of Argentina and Uruguay.
As Argentina and Uruguay were still officially neutral in December of 1939, the German ship could enter their waters with relative ease. Chilled relations between them and Germany left them disinclined to let that happen without keeping a very close eye on the ship and any communications it might make to the mainland.
On December 13, British naval ships engaged the Graf Spee off the Uruguayan coast and inflicted heavy damage upon it. The Graf Spee set a course for the port of Montevideo to put in for repairs.
No sooner had it altered it’s course for the port when it was over flown by a flight of six torpedo armed Argentine Yararas. Shortly after, a burst of 20mm cannon fire from the lead aircraft of a formation of four Uruguayan Yararas armed with four 20mm cannons and a pair of 500 pound bombs each flew over the Graff Spee’s bow at bridge height.
A sailor manning one of the German ship’s lighter gun stations opened fire on the second Yarara formation. He was quickly relieved of his post as he had opened fire without permission, but the damage had been done. One of the Yararas from the second formation had been hit and spun into the ocean, killing both crew members in the process.
Neutral No Longer
The radio room of the Graf Spee was a frenzy of activity, the capatin had ordered communication to be established with the mainland in spite of the considerable damage the equipment had suffered in battle with the British ships.
The captain watched the second formation of Yararas turn for a second run at his ship. Through his ship’s damaged radio equipment, he had received no warning of the initial targeting of his boat by the Yararas, nor explanation of why he was being denied access to a neutral harbour. Worse, he could not send a message to explain that the lost aircraft had been shot at and destroyed without permission and to request the remaining aircraft hold their fire.
As a rain of 20mm ammunition sheared into the bridge and surrounding superstructure, it was all too clear that the downing of the Yarara had been taken as an act of war by Uruguay. As the frantic crew scrammbled to either escape or extinguish flames, the six Argentine aircraft began their torpedo run.
Four of the six torpedoes had found their marks and the Graff Spee’s port side was layed open to the ocean leaving the remaining crew nothing to do but abandon their rapidly descending ship.
Argentine naval ships moved in to rescue the Graf Spee sailors and transport them to Montevideo. As the incident had occurred in Uruguayan territory, the crew would be handed into the custody of that country’s authorities.
Into the Fray
Later that same day, Germany formally declared war on Argentina and Uruguay. In response, The Uruguayan government declared the remaining Graff Spee crew and the entire staff of the German embassy to be prisoners of war.
At the same time, in accordance to the treaty the three nations had, Brazil declared war on Germany and took all German diplomatic staff on Brazilian soil at the time as prisoners.
At the time, the Brazilian and Uruguayan naval fleets were largely obsolete so the bulk of naval presence in the region was split between Argentina, which had the eighth most powerful navy in the world at the time, and Great Britain.