United States of Mexico (1917)
Heavy Tank Prototype – At least 1 Built
Mexico is not a country which is often associated with tank production of any kind. What is more, as of 2018, Mexico does not have any tanks at all in their army – their armored forces consist of armored cars, most numerously the Panhard ERC, which is nearing 35 years of service. As such, it may come to a surprise that in 1917, Mexico joined a very select group of tank producing nations, and by doing so, beating their bitter rivals north of the border.
Context – The Mexican Revolution
The Mexican Revolution is one of, if not the most important events in Twentieth-Century Mexican history, completely changing the sociopolitical fabric of society. For over three decades, Mexico had been ruled by what is known as el Porfiriato, in other words, the presidency of General Porfirio Díaz, until he was forced to resign in 1911. Shortly before that, after fixing an election result in 1910, the people were mobilized against Díaz.
During his presidency, Díaz had made many enemies, and his successor was one of them, the liberal Francisco I. Madero who tried to introduce democracy and freedom of press and association. Following such a long lasting period of rule by one person, a political vacuum was created in which different political elites and social groups fought to take power. Madero had enemies on all sides of the political spectrum – some viewed him has too reactionary, and others as too liberal revolutionary – so he was forced to resign alongside his vice president in a coup in February 1913, with both being assassinated soon after. The counter-revolutionary General Victoriano Huerta took over after the coup and ruled in a dictatorial manner until July 1914, when he resigned and went into exile after a series of defeats of his Federal Army.
By this point, Mexico was submerged in a full-scale civil war. A coalition of revolutionary forces would take over the capital and therefore seized power, but not for long as they failed to land an agreement to form a government. The conservative Venustiano Carranza, who had been instrumental in the coup against Huerta in 1913 and had support from the USA, emerged triumphant from the chaos of the civil war, defeating the famous revolutionaries Pancho Villa and Emiliano Zapata along the way. With the signing of the Constitution of 1917, the situation would stabilize for some time. Following the signing of the Constitution and up to 1920, clean-up operations were carried out and agrarian revolutionary leaders were assassinated or imprisoned. The general atmosphere of turmoil and uncertainty benefited radical ideas and banditry alike. The ten years of continuous warfare would leave between 1 and 2 million dead Mexicans, including military and civilian deaths.
The Steps Towards Tank Production
Mexico had never been a major arms producer and had always had to depend on foreign imports for any major military operation. The constant situation of warfare during the Revolutionary period exacerbated the need for armament. With this in mind, a pro-government group (Constitutionalists), under the orders of General Venustiano Carranza, led a project to build armament factories for home production in 1915. By 1917, the Escuela Militar de Aviación [Military Aviation School] and Talleres Nacionales de Construcción Aeronáutica (TNCA) [National Aircraft Construction Factories] were inaugurated in Mexico City.
TNCA had originated as a small repair workshop and spare part supplier for the equally small Mexican air-force but slowly increased in size with the introduction of heavy machinery imported from Europe. Eventually, it would even produce its own aircraft, including the TNCA A to H Series and a few licensed British and American aircraft.
At some point in between 1916 and 1917, Carranza’s nephew, the aviator Major Alberto Salinas Carranza, is attributed to having designed a tank which would receive the name ‘TNCA Salinas’ – TNCA after the factory where it was built and Salinas in honor of its designer – although the tank is more commonly known as ‘Tanque Salinas’ (Salinas’ tank).
What ideas were behind the need for this tank are unknown. By 1917, the civil war and consolidation of power by Carranza were all but complete. One must also consider that unlike the Great War in (mostly Western) Europe, warfare in Mexico had not been limited to trenches. In the vast plains and deserts in the center and north, horses and mounted mobile warfare was still important, whilst in the jungles of the south, guerrilla warfare was favored. Tank technology at the time was not advanced enough for tanks to cover these large distances and to fight in this typically mobile warfare. The tank would have been more suited to the multiple urban combats that occurred during the Revolution and to put down uprisings within cities or towns.
Tanks were a new phenomenon and states around the world did not want to be left lagging behind in adopting this technology. Mexico would not be left either, and within an atmosphere of war favoring technological innovations, eager and adept engineers like Salinas could have been free to develop their ideas.
The TNCA Salinas next to its presumed designer, Major Alberto Salinas Carranza. The five-barrel revolving cannon can be appreciated in this photo. The vehicle is probably perched on some sort of stand. The rollers for the track are visible as are the spaces for the track tensioners although no track is fitted. Photo: SOURCE
Externally, the tank resembles the early British rhomboid tanks (such as the Mk. I) which had tracks on each side surrounding the hull and covered the entire length of the machine. Its main gun position, however, owes more to the contemporary French design of the St. Chamond.
On each side, there were sponsons to carry the secondary armament consisting of a machine-gun on each side (unlike the British tanks where the main armament would be on the sponsons). The sponsons, unlike the large square British ones, were curved and shaped like a British pillar-box. Also, unlike the British detachable sponsons, these seem fixed to the side. Atop the tank, there was a large box-like cabin – similar to those on the Mk.V (and other later rhomboid tanks) – for the driver and commander.
It seems from photographic evidence that in front of the sponsons there were doors for crew access on each side, which, in combat, would have been quite a design flaw as: a) the machine-guns would not be able to fire forward if the door was in use; and b) crewmen would be vulnerable when exiting the tank in middle of combat if the door was facing forward.
Armor details are not described, but given that the vehicle is estimated to be around 7 meters in length and 20 tons in weight and a similar vehicle, the Mk.I’s 7.9 meters and 27-29 tons with 6-15mm in armor, the armor of the TNCA Salinas can be approximated to 6-12mm. This armor was riveted, and from the photos, it seems it was constructed onto an internal frame.
The front upper hull had a large square through which the gun was fired. It seems the gun was not fitted into the hull but rather mounted internally and the gun’s original gun shield was used for interior protection. Some sources state a 47mm Hotchkiss revolver cannon consisting of five barrels as the main armament, but this may well be a typo. It is documented that at the time of the Mexican Revolution there were Hotchkiss 37mm Revolving Cannons, also with 5 barrels, but there is not mention of a 47mm variant, and the description provided matches that of the 37mm. A typo between a 3 and a 4 is easy to make and with time, this typo has come to be accepted as a fact.
Martínez Hernández et al., probably the most reputable source on the tank, state that it was, in fact, the 37mm version, which could have been found on board the battleship Ignacio Zaragoza. This gun was accurate and had a quick reload time, but had its drawbacks, including the fact that it did not have a long range and that it was quite heavy as it was mainly intended to be used on ships or coastal defense (though it was used as field artillery during the war), not early tanks. Each round weighed around 1.1kg and that the gun with a muzzle velocity of 455 m/s. Firing a solid AP shot this gun could perforate 45mm of steel at close ranges.
Some sources mention that an unspecified 75mm gun, though it could be the Mexican variant of the 75mm St. Chamond field gun known as the Mondragón-St. Chamond, was also tested, but there is no conclusive evidence of this. The caliber or make of the side machine-guns is not known.
A Hotchkiss 37mm Revolving Cannon at Fort Copacabana, Brazil. Photo: Wikimedia Commons
Illustration of the Salinas Tank modeled by Mr. C. Ryan, funded by our Patreon Campaign.
Inside the Tank
Inside there would be a crew of between 6 and 8. A commander, a driver, two to three crew members to operate the main gun in the front and two machine-gunners (one on each side). The potential eighth crew member is unspecified but could have been an engineer.
Details concerning the engine differ, but what is assumed is that it would have been a diesel engine of around 90-100hp. The 6 cylinder Aztatl 80 hp – the first Mexican indigenous airplane engine – could have, according to all available sources consulted, been used, as it was first produced in 1917. Alternatively, at this time in Mexico, there were Hispano-Suiza 150hp, Wright 60hp, and Renault ~60hp engines for aircraft which could also have been used. However, it could make more sense to think that the tank would have used some sort of truck engine, which would have been much more readily available and in less demand than the latest type of aircraft engine. It is worth mentioning though that TNCA was a company involved in aircraft parts production and as such, could have used an aircraft engine which would have been available at the time.
On the other hand, Martínez Hernández et al. doubt that the tank had an engine at all. In the few available images of the vehicle, there are no obvious signs that it ever moved under its own power, so it could well be that whatever engine was desired was never actually fitted.
Side-view of the TNCA Salinas in which its postbox-like sponsons can be appreciated. The identity of the man posing with the tank is unknown. Photo: SOURCE
Short Operational History and Demise
It is unknown if any additional vehicles to the prototype were produced in series, but it is highly unlikely. There is also very little information regarding what happened to the tank.
Speculation exists within the sources that the tank could have been deployed in combat twice, though this is highly unlikely. The first supposed use would be in some period between 1919 and 1921, during the last stages of the Mexican Revolution, and the second in 1926 in putting down the Catholic clerical rebels during the Cristero War (1926-29). As previously stated, there is no supporting evidence of this, so, for now, these will be left as conjecture.
The company TNCA was eventually bought by Canadian Car and Foundry, but before then the company was on a spiral decline due to lack of government investment and a preference for foreign aircraft. The ‘Tanque Salinas’ would end its operational life sometime during the 1930’s when it was converted into a guardhouse or checkpoint outside the air base at Balbuena, near Mexico City, not too far from where the tank was originally built. The main gun was removed and from photographic evidence.
It is unknown what happened to the tank after this, but it was most likely scrapped at some point. Mexico would not have any other tanks until the nine Marmon-Herrington CTVL tanks acquired from the USA in 1938.
The Tanque Salinas presumably at the Balbuena air base lacking its main armament. In this picture, it can be perfectly appreciated that the gun was not affixed to the frontal plate but rather mounted internally and protected on the inside only with its gun shield. The open space seen through the gun opening would have been the open right-hand-side door. Photo: SOURCE
Although the TNCA Salinas was never going to blaze the trail for a new tank concept, but it was an important milestone in the history of tank design by being the first tank designed and built outside Europe. Unfortunately, not much is known about the tank and there is very little scholarly work on the history or development of the vehicle, which is unfair given its importance, meaning that it deserves a better legacy.
Its design proved that the Mexican engineers and elites were not only aware of events happening in Europe but were able to adopt various different ideas (a rhomboid design and forward facing main gun not mounted on sponsons) into one suited to their own purposes. That said, it is unknown how well, if at all, Tanque Salinas worked, and it was most likely never used in combat or even in training operations.
|Dimensions (L-W-H)||Est. 7 x 3 x 2 m (22.96 x 9.84 x 6.56 ft)|
|Total weight||Est. Around 20 tons|
|Crew||6-8 (Commander, Driver, 2-3 Gunners, Two Machine-Gunners, possibly 1 Engineer)|
|Propulsion||6-Cylinder Aztatl 80 hp|
|Armament||Naval 37mm Hotchkiss revolver cannon|
2 x machine-guns
|Armament Female Tank||4x 0.303 inch (7.62mm) Vickers water-cooled machine guns|
1x 0.303 inch (7.62mm) Hotchkiss air-cooled machine gun
|Armor||6-12mm (0.24 – 0.47 in)|
Links & Resources
Anon., Gral. Div. P.A. Alberto Leopoldo Salinas Carranza (2011). (LINK) [accessed on 30/08/18]
Anon., The Hotchkiss 37mm Revolving Cannon (2010). (LINK)
‘Coldown’, El primer tanque de Latinoamérica (2016). (LINK) [accessed on 29/08/18]
David Cummings, TNCA Salinas (Tanque Salinas), Mexico’s First Indigenous Tank (2013). (LINK) [accessed on 29/08/18]
Samuel Banda, TNCA Salinas: El primer tanque mexicano (2012). (LINK) [accessed on 29/08/18]
‘Tlileztly’, TNCA Salinas “Tanque Mexicano inicios del siglo XX (2017). (LINK) [accessed on 29/08/18]
Mario Alejandro Martínez Hernández (ed), Sentinel Dossier 1 El mundo de las fuerzas armadas mexicanas (Marzo 2016)
Philip Jowett and Alejandro de Quesada, Osprey Elite #137 The Mexican Revolution 1910-20 (Oxford: Osprey Publishing, 2008)