Medium Tank – 12 Built
Due to long standing rivalries with the Republic of Brazil and, in particular, the Republic of Chile, over the control of the Patagonia region, during most of the Interwar period, the Argentine military was continually upgrading and rearming itself in case of war. However, Argentina was falling behind in the development of its mechanized forces. As a solution, Argentina developed its first tracked medium tank, the Tanque Mediano Nahuel Modelo Baisi 1943 [Eng. Nahuel Medium Tank Model 1943 Baisi], inspired by the M4 Sherman Medium Tank.
The Argentine “Big Cat”
In order to catch up to the rest of the world, in 1937, Argentina purchased 12 Vickers-Carden Loyd mod. 1934 light tanks which arrived in 1938, in preparation for future rearmament plans. These included the purchase of 160 Škoda tanks based on the TNH design. Due to Germany’s annexation of Czechoslovakia, however, these plans were halted.
During the following years, Argentina was sidelined by the start of WW2, isolated because of its policy of neutrality and the ailing health of its president. Between 1943 and 1944, Brazil began receiving military aid from the United States, procuring 3 M3 Half-Tracks, 81 M3A1 Scout Cars, 54 T17 Armored Cars, 437 M3A1 Light Tanks, 104 M3 Medium Tanks, and 53 M4 Medium Tanks. In total, Brazil received around 732 AFVs from the United States, vastly outnumbering Argentina’s armored fleet.
Argentina had to come up with a solution to its lack of modern tanks. Eventually, this would be relieved with a large purchase of M4 medium tanks of its own once Argentina began to rebuild its diplomatic ties with the United States. Nonetheless, prior to that, it needed an immediate response to the escalation in the arms race with Brazil. Along with the Nahuel, the Vehículo de Asalto de Infantería Vinchuca [Eng. Infantry Assault Vehicle Vinchuca] and the Tractor de Artillería a Orugas Yacaré [Eng. Tracked Artillery Tractor Yacaré] were built.
As with the Vinchuca and its contemporary, the Yacaré, the Nahuel was named after an animal endemic to Argentina. “Nahuel” is Mapundugun for “jaguar”, or as it is known in Argentina, “yaguareté”, the only extant member of the Panthera genus in South America. It tends to hunt larger prey, utilizing the neck biting method utilized by other members of the Panthera genus, and also uniquely biting through the temporal bone of its prey, piercing the brain. They are also strong enough to kill smaller prey by clawing them.
While jaguars do attack humans, usually when they are old or injured, these attacks are very uncommon. Many sources call the Nahuel tank a “tiger”, but while they are related, it should be noted that the tiger and the jaguar are not the same animal.
History and Development
In 1937, the Argentine Army bought 12 Vickers Carden-Loyd mod. 1934 tanks from Vickers to prepare for the arrival of Czechoslovak TNH-based tanks. Because the Czechoslovak vehicles never arrived due to the annexation of the country by Germany, these vehicles had to form the backbone of Argentina’s armored forces until 1944. They were assigned a new name, Tanque Liviano Vickers Modelo Argentino 1938 [Eng. Vickers Light Tank Argentine Model 1938” (these tanks were Vickers mod. 1934 tanks, however they arrived in Argentina in April 1938, hence the designation), and saw use along 12 obsolete Crossley mod. 1924 armored cars.
The Army was in trouble, as it could not secure equipment from the Allied powers due to the Argentine military’s ideological proximity to the Axis powers, and especially Germany, and because Czechoslovakia was under German occupation and could not spare any production for Argentina. To strengthen the military, on October 9th 1941, with Ramón Castillo as acting President whilst Roberto Marcelino Ortiz was ill, Ley 12.709 [Eng. Law 12.709] was passed, which would replace existing vehicles with indigenously manufactured ones.
The law arranged the creation of an indigenous military industry under the Dirección General de Fabricaciones Militares [Eng. General Directorate of Military Fabrications], commonly abbreviated as DGFM. It was given control of military ordnance planning, mines to extract resources from, and the capacity to produce AFVs, small arms, and munitions. It would be responsible for the creation of the Nahuel tank, the Vinchuca troop transport, the Yacaré artillery tractor, the ALAM.1 machine gun, the FMK-3 submachine gun, the FARA-83 assault rifle, and the 75 mm and 105 mm Czekalski series of recoilless rifles.
Lieutenant Colonel Alfredo Baisi had been involved in the conversion of TD-35 tractors into Yacaré and Vinchuca armored vehicles in 1944, which made him, in the eyes of the Army, the strongest candidate to create designs for the nascent industry. In 1943, Baisi, along with Major Francisco A. Villamil and his team, received the task of designing a 35 tonnes medium tank, which was completed in 45 days. They built a wooden mock-up based on a TD-35 agricultural tractor, and a 1:1 mock-up, designated “251”, of the future Nahuel tank.
Two months later, the first Nahuel prototype was manufactured, “c.252”, turretless and missing its front glacis, and shown off to non-elected President Brigadier General Edelmiro Farrell, Navy Minister Counter Admiral Alberto Tesaire, and War Minister Juan Domingo Perón, future President of Argentina. It was driven by an artillery non-commissioned officer (NCO) with the surname Mutto, who had previous experience driving a Renault FT in France.
It is impossible to ignore the influence the Sherman and the M3 Lee had on the Nahuel. At some point, Baisi and his team must have come in contact with the design of the early Sherman from other sources, given that it still had the original design of hull machine guns, a similar arrangement, and even a similar VVSS type suspension. Like the Yacaré and Ñandú, the Nahuel had an animal painted on the right side of its hull. The tank was designed for ease of manufacture, with the hull having mostly straight, simple shapes, while the turret and tracks were easily the most difficult parts to manufacture.
The effort to build the tanks employed around 80 different factories and establishments, with all three elements of the Fuerzas Armadas de la República Argentina [Eng. Armed Forces of the Argentine Republic] being involved in the development. The Air Force supplied the engines, which were licensed and modified Lorraine-Dietrich 12EB’s manufactured by Fabrica Militar de Aviones [Eng. Plane Military Factory] between 1931 and 1932 and the Navy offered its ship armor laboratory and the communication system, which Oscar Baisi, Alfredo Baisi’s brother, worked on.
Steel was provided by the Fabrica de Aceros Especiales [Eng. Factory of Special Steel], part of DGFM, in Valentín Alsina. Talleres Metalúrgicos San Martín (TAMET) [Eng. San Martín Metallurgic Workshop] manufactured the turrets in large dome-shaped ovens. The workshops in Ferrocarriles del Estado [Eng. State Railroads] were used to manufacture the turret rings, which were then sent to the Instituto Aerotécnico Nacional (I.Ae.) [Eng. National Aerotechnical Institute] in Córdoba for machining.
Yacimientos Petrolíferos Fiscales (YPF) [Eng. Fiscal Oilfields] produced the fuel necessary for the operation of the Nahuel tank. The chassis was built in the shipyards of the Ministerio de Obras Públicas [Eng. Ministry of Public Works] in Isla Maciel. The guns and ammunition were obtained from depots of the Dirección General de Material del Ejército (DGME) [Eng. General Directorate of Army Materiel]. Pedro Merlini provided the transmission. The assembly of the tank was done in Arsenal Esteban de Luca [Eng. Esteban de Luca Arsenal].
|Fábrica de Aceros Especiales||Steel|
|Ferrocarriles del Estado||Turret ring|
|Ministerio de Obras Públicas||Chassis|
|Arsenal Esteban de Luca||Final assembly|
During tests on the Nahuel tank, it was tasked with wading a deep creek, and military authorities, concerned with possible issues during the demonstration, reinforced the river bed with gravel. As the wading was being performed, midway through the crossing, the Nahuel’s engine began to roar as it made its way through the river, before making it out of the other side. They were surprised as the Nahuel bulldozed its way through the gravel, bringing it to shore, but the vehicle’s capabilities were confirmed.
In 1944, the Nahuel was placed into production and was first shown off to the public in an exhibition on June 4th 1944 to commemorate the first anniversary of the 1943 coup d’état. Two of them were exhibited, although they did not have their engines since their transmissions were still being tested and finished at Arsenal Esteban de Luca. They opened the show in a spectacular fashion by firing their main guns and promptly scaring the spectators, who likely had never seen a tank before.
Almost a month later, on July 9th 1944, 10 of the finished Nahuel tanks were shown off to the public in a parade celebrating Argentina’s Independence Day. In charge of the parade were Major Salinas, First Lieutenants Warnholtz and Fernandez, and Lieutenant Campos. The lead tank was commanded by Baisi himself.
According to the newspaper “La Nación”, the tanks were escorted by motorcycles and left clouds of smoke and dust as they advanced. This is the likely source for the claims that the Nahuel’s engines were faulty or otherwise could not combust properly. While there are various pictures which seem to corroborate this fact, there are pictures of the tanks in movement without any smoke present. Explanations vary from some engines being in poor condition, the engines creating excessive smoke when accelerating, the street being covered in dust, on purpose or not, to the drivers showing off their tanks by performing burnouts.
The parade was a success, and for his work, Baisi was congratulated in the Boletín Militar Público N°210 [Eng. Public Military Bulletin] on June 24th 1944, where his achievement of designing and producing a tank with no dedicated heavy industry and no documentation or blueprints to base himself off of was proudly celebrated. However, due to army regulations, he could not be promoted, and stayed a lieutenant general. The tank was also given its official designation, “Nahuel Modelo Baisi 1943” [Eng. Nahuel Model Baisi 1943]. This was to be read in front of troops, civilians, and workers, and it was going to be made public, added to Baisi’s file, and archived in the Dirección General del Personal [Eng. General Direction of Personnel].
In this bulletin, an alternative name for the tank is referenced, “Nahuel marca D.L. 43” [Eng. Nahuel mark/model D.L. 43], which implies that “D.L. 43” is an industrial designation for the vehicle. The song “Nahuel”, with lyrics by Carlos M. Smith and instrumentation by Alberto Cifolelli, was also published in it.
The name of the vehicle comes from the Mapudungun for “tiger”, a language used by the indigenous Mapuche people of Chile and parts of Argentina. According to legend, it was inspired by a comment of the Brazilian military. When an American attaché sought assessment in the possibility of Brazil invading Argentina, he was told “do not worry, the tiger is toothless”, and this information was allegedly intercepted by German intelligence in Brazil and relayed to the Argentine government. What is certain, however, is that during the June 4th exposition, military planes dropped flyers over the City of Buenos Aires, declaring that “we will have teeth, and they will be sharp”.
As for the “D.L.”, its origin is far more uncertain. There are two versions for its origin. In the first one, when President Farrell was presented the Nahuel project, he reputedly enthusiastically exclaimed “déle, déle nomás!”, an expression, seemingly usual from him, which is used as a very positive approval of something, with the implication of full support. The alternative is that it comes from the June 4th march, a musical composition, of the Revolution of 1943, which was composed by Colonel Blas Alfredo Lomuto, and repeatedly utilizes the phrase “vamos compañero, dele dele, a trabajar…”, translated as an order or plea to work. However, as the Arsenal Esteban de Luca is often referred with the initials D.L. in military records, it likely just indicates their origin.
The tank’s design would go through a series of modifications in 1947 to convert the vehicle into a more effective combat machine. The modernized Nahuel tanks have become known by various designations, such as “Nahuel mod. De Luca” (in contrast to the earlier “Baisi” version), “Nahuel Reciclado” [Eng. Recycled Nahuel], or “Nahuel mod. Sosa Molina”. In this article, it will be referred to as “Nahuel mod. 1947”, following Argentina’s AFV designation system at the time, but this name is unofficial and only for convenience, as even after modification, they kept the D.L. 43 designation marking on the side of the hull.
Alfredo Aquiles Baisi
Lieutenant Colonel Alfredo Aquiles Baisi was a second generation Italian immigrant born in 1902, son of Captain Adolfo Vincenzo Baisi, an officer in the Royal Italian Army, and his wife, Carlota Allende. His brother was Oscar Baisi, who entered the Argentine Navy.
Adolfo Baisi was born in the latter half of the 19th Century in Alvito, Italy. He graduated from the Accademia Militare di Modena [Eng. Modena Military Academy] and enlisted in the Royal Italian Army, being promoted to the rank of captain. Attracted by America, he emigrated to Uruguay, where he would work as a Professor of Mathematics, Greek, and Latin. When he arrived in Buenos Aires, Argentina, Adolfo Baisi joined the Argentine Army and revalidated his rank as captain, working as an Artillery and Ballistics Officer, introducing mathematics and statistics into his discipline. In Cordoba, he met Carlota Allende, marrying her and having two children. He remained in the Army for years before retiring and ending his career as a professor in the Colegio Militar de la Nación [Eng. National Military College], with the rank of lieutenant colonel.
Alfredo Baisi followed in his father’s footsteps, with the first recorded event of his career being his role as a military attaché for the Argentine Embassy in the USA. He introduced indirect fire into the artillery units, and designed the outfits for Argentine Army tankers and infantry in 1935. German influence permeated the Argentine Army since the early 20th century, determining political affiliations, weapons, uniforms, and parades, which reflected in his own choices for the newly-made uniform, which sported Stahlhelm-style helmets and tunics inspired by the summer Wehrmacht outfit.
Baisi’s power grew and he represented his country in the Inter-American Defense Board, created on March 30th 1942, with Argentina as a founding member. He held the position of director of Arsenal Esteban de Luca and Subsecretario de Industria y Comercio [Eng. Industry and Commerce Subsecretary]. He also became Interventor de la Dirección Nacional de Vialidad [Eng. National Traffic Direction Interventor], which gave him the task of examining documents, accounting books, and inventories to inform the Tribunal de Cuentas [Eng. Court of Accounts], which had the task of approving the DNV’s budgets.
Baisi was one of the original founders of the Grupo de Oficiales Unidos (GOU) [Eng. United Officers’ Group] alongside Juan Domingo Perón, which overthrew Ramón Castillo’s presidency in the country’s second coup d’êtat.
By 1944, he held the rank of lieutenant colonel and had shown opposition to Perón, who was not president yet, in the decision to sever diplomatic ties with the Axis powers. This disagreement led to Baisi’s support of Colonel Luis César Perlinger, along with a few officers, in a power struggle with Perón for political leadership in anticipation of the next democratic period of Argentina. The incident led to the Peronist government to order his retirement from the Army in 1950, before he could be promoted to general.
During the next years, he was involved in scientific magazines as a publisher and researcher, developing a calculator for indirect fire for the Argentine artillery. He passed away aged 73 in 1975. He had one son, also named Adolfo Baisi, who worked as an engineer.
One discrepancy between different sources is the amount of Nahuel tanks built. Nahuel DL 43 by Ricardo Jorge Sigal Fogliani, the main source used in the article, states that according to army inventories and Lt. José Javier de la Cuesta Ávila there were a maximum of 12 Nahuel and the wooden mock-up. Other authors claim there were 16 and Georg Von Rauch claims 23 tanks were produced. This discrepancy is likely due to the Nahuel’s later modifications making it seem that there were two series of tanks produced.
Exterior and Interior
The Nahuel mod. 1943 closely resembled the Sherman, with some notable differences, mostly the simple design, with angled armor plates and a conical turret. It was painted in a shade of green with a reflective finish, and had numerous markings. Most notable is the jaguar drawing on the hull’s side, near the driver or co-driver’s position, depending on the side. Other markings included “Ejercito Argentino, Agrupación Patagonia” [Eng. Argentine Army, Patagonia Group] around the Argentine roundel, “Nahuel D.L. 43” below the jaguar, and the tank’s number at the rear.
The Nahuel had two headlights without frontal covers, and a second headlight on top of the turret above the loader’s position. There were three hatches, two for the driver and co-driver, and one for the commander. The driver/co-driver hatches had one periscope each and opened vertically, blocking the crew’s view while opened, while the commander’s hatch had a split design, but no periscopes. The hull had attachment points for tools on the sides, which included a shovel, an ax, and a pickaxe. The start-up crank was stowed on the rear of the hull, along with other equipment.
The interior was fully lit, well ventilated, and had heating available. The configuration for the crew was the driver to the left with a co-driver, who also operated the Madsen machine guns, to his right, and the three remaining crew, the loader/radio operator, the gunner, and the commander, in the turret.
The turret was capable of traversing 360°, engaged manually through a crank. Ammunition was spread around the base of the turret, and additional ammunition was likely stored in the hull. Externally, it had 4 towing hooks and attachment points for additional tracks in the rear.
The commander and the gunner were located on the right side of the turret. The commander had the only hatch in the turret, with a rotating periscope in front of him, the radio to his left, and a pistol port to the right. The gunner sat in front of the commander, and had his own fixed periscopic sight, which would be used to aim the cannon. The loader sat to the left, behind him was the radio, and to the right was another pistol port.
Main Armament and Ammunition
The Nahuel’s primary armament was the Krupp mod. 1909 L/30 75 mm cannon. These cannons were acquired in 1909 and 1910 as the Krupp mod. 1909 and modernized in 1923 as the Krupp mod. 1909/23. With this upgrade, the Krupp cannons received a modest modernization, with a new carriage and aiming systems. Around 516 cannons were obtained by DGME, with a lot of them still in their factory boxes and covered in their original cosmoline. Ten cannons were initially made available to Baisi for the Nahuel.
Due to the Krupp mod. 1909’s high recoil, it was mounted into the tank using 2 hydraulic recoil cylinders above and below the barrel, covered by the mantlet. It used a periscopic optical sight which was mounted in the gunner’s position in the turret, which the commander also had available. These optics were made by Carl Zeiss and were based on Goerz artillery sights, and were standard to all Krupp field guns. These sights had a 4x magnification and a 10° field of view. Their usage for both crewmembers makes sense, since they were not only used for aiming field guns, but also for spotting. According to the crews that operated the Nahuel, the optics had a tendency to lose zero due to being loosely fitted.
Information about the Krupp mod. 1909 is relatively scarce. It had a firing range of 7,700 m, a rate of fire of 20 rpm, a muzzle velocity of 510 m/s, and a shell weight of 6 kg for both Shrapnel and High Explosive variants. The shrapnel shell contained 295 steel balls, weighing 9 g each.
It was chambered to 75×278 mmR, for which there were High Explosive and Shrapnel shells already available. It is claimed that the Nahuel did not carry Armor Piercing shells, but since the Nahuel was intended to fight enemy armor, solid AP shells were developed. It is far-fetched to think that the project’s attempt to create a modern medium tank would not have considered such an important detail.
|Krupp mod. 1909 L/30 (75×278 mmR)|
|Projectile and Type||Velocity||Weight||Filler||Fuze||Penetration (100 m at 30°)|
|HE||510 m/s||6 kg||Unknown||Unknown||Unknown|
|Shrapnel||~510 m/s||6 kg||295 x 9 g steel balls||Unknown||Unknown|
However, Bofors mod. 1935 projectiles were interchangeable with Krupp mod. 1909 projectiles, due to Bofors being partly owned by Krupp and reutilizing elements from their designs. It is possible these AP shells were reused from the Bofors cannons. The Bofors L/40 mod. 1935 had the following projectiles available.
|Bofors mod. 1935 L/40 (75×278 mmR)|
|Projectile and Type||Velocity||Weight||Filler||Fuze||Penetration (100 m at 30°)|
|GO (AP)||625 m/s||5 kg||None||None||Unknown|
|AEAT (Version 1) (HE)||~510 m/s||5.7 kg||547 g||Unknown||Unknown|
|AEAT (Version 2) (HE)||~510 m/s||6.35 kg||Unknown||Unknown||Unknown|
|AEAT (Version 3) (HE)||510 m/s||6 kg||Unknown||Unknown||Unknown|
|AES (Shrapnel)||Unknown||5.3 kg||Unknown||Unknown||Unknown|
It is worth noting that the Bofors was considered as an upgrade for the Nahuel. In 1951, the Czekalski recoilless rifle finished development, and due to cross-compatibility (the Czekalski used modified 75 mm Bofors shells), the ECH, a HEAT projectile, would be in theory usable by the Bofors as well.
Whether these were actually used in the Krupp cannons is unknown, although performance would have been different due to the shorter barrel. Similarly, the Matorras mod. 1945 75 mm L/13, a Krupp cannon modified into an infantry gun, was capable of firing 75 mm Bofors projectiles. The amount of shells carried by the Nahuel is unknown.
A Madsen 11.35 mm heavy machine gun was mounted coaxial to the gun. An unusual choice for a coaxial heavy machine gun, it was already used by the predecessors of the modern Argentine Air Force in their Curtiss H-75O Hawk fighters and Ae.MB Bombi light bombers. It was an enlarged version of the regular 7.65 mm Madsen machine gun, likely a belt fed and pistol grip version, but there were ground variants fitted with regular box magazines and spade grips. It had a cyclic rate of fire of 900 rpm, a barrel length of 750 mm, and a weight of 15.9 kg when fully loaded with 100 rounds of 11.35 mm ammunition. The Nahuel carried an unknown amount of ammunition for this machine gun.
Kynoch was the main manufacturer of 11.35×62 mm ammunition through most of the Madsen’s service history with the Argentine Army, but from 1940 to 1946, it was manufactured by the Fabrica Argentina Militar de Municiones y Armas Portátiles [Eng. Argentine Military Factory of Munitions and Firearms], which would later be integrated into DGFM. Two million rounds of ammunition were produced by FAMMAP, of which there were Ball, Armor Piercing, and Incendiary Tracer variants. The shells weighed 19.83 g, and they were fired at a muzzle velocity of 850 m/s. Using AP rounds, it had a penetration of approximately 20 mm of RHA at 10 m.
Also fitted in the mod. 1943 variants were three glacis-mounted Madsen mod. 1926 machine guns, tank mounted variants with a belt feed and a pistol grip. The Madsen was a 7.65×53 mm Argentine light machine gun, with a rate of fire of 450 rpm, fed by 32 round box magazines at an unknown muzzle velocity, although the 6.5 mm version had a velocity of 870 m/s. Rounds were produced by FAMMAP, and contracted to other countries, such as Belgium, for military use. The ammunition types available were Ball, Armor Piercing, Armor Piercing Tracer, Tracer, Incendiary, Incendiary Tracer, and High Explosive.
In addition, the crew was provided with a number of .45 ACP small arms as self-defense weapons. These included Colt mod. 1927 pistols, Ballester-Molina pistols, and most interestingly, Halcon mod. 1943 submachine guns. These submachine guns were of good quality and comparable to the M1 utilized by the US Army. They were fed by either 20 or 40 round magazines and had a rate of fire of 600 rpm. The pistols were slightly modified copies of the Colt M1911.
The Nahuel’s most favorable asset was its strong armor. It was made from a strong, heat resistant, nickel and steel alloy, which due to the short production run was not a considerable drain on resources. The hull was mostly welded, but it had riveted areas as well, most notably the rear of the hull, while the turret was cast. This armor was falsely reported by US authorities to be salvaged ship armor or even scrap metal, but they were corrected by Argentine authorities.
The tank’s frontal protection surpassed its inspiration and rival’s, the Sherman. Sloped at 55°, the Nahuel had a very strong 80 mm thick upper glacis, giving it a line of sight thickness of around 139 mm. This thick front glacis was possibly inspired by the German Panther’s, which had the same arrangement. It was also an equally large downside, as the Nahuel’s suspension was considerably strained from the weight of the glacis, with the front bogies being close to full ballast.
The other exact armor thickness value known is the belly armor at 25 mm. The remaining values are speculative, since no measurements have survived. Based on analysis of photographs of the hulls during manufacturing and a side profile of the tank, the side armor seems to have been around 50-65 mm thick, sloped at 10°, while the lower glacis seems to have had a similar thickness, sloped at 40°. The roof was quite thin, most likely around 10 mm thick. The rear values are unknown, but the engine deck was sloped at 10°.
The turret’s front was 80 mm thick, sloped at 30°, and rounded due to its cast shape, which due to the overlapping mantlet, offered very good protection around the gun. The thickness of the turret’s sides, rear, and roof, as with the hull, are unknown, however, they were likely similar to the hull’s. The rear and sides of the turret were sloped at 15°. The tank’s vision ports were also outfitted with ballistic glass.
The automotive components were the hardest to manufacture of all of the tank’s components. The Nahuel had been tested with two different engines. The first, chosen for its production run, was the Lorraine-Dietrich 12 Eb W-12 radial aircraft engine, manufactured in 1930-1932 for use in Argentine built Dewoitine D.21 fighters, uprated to output 500 CV (493 hp) at 2,500 rpm, similar to the Continental R-975 used by the M4A1 medium tank.
The second was another Dewoitine D.21 engine, this time taken off non-Argentine manufactured D.21s, the Hispano-Suiza 12 Gb W-12 with an output of 500 hp. This option was rejected because it almost caught fire during trials.
A third engine was also considered, the I.Ae. 16 El Gaucho engine, which was a copy of the Wright R-975 Whirlwind 9 with an output of 450 CV (444 hp), however, it seems it was never tested.
|Lorraine-Dietrich 12 Eb||W-12||493 hp|
|Hispano-Suiza 12 Gb||W-12||500 hp|
|I.Ae. 16 El Gaucho||9-cylinder radial||444 hp|
The Eb 12 was water cooled and mounted at the rear of the vehicle. The radiator was adapted for the Nahuel by Colonel Bidone, with two exhausts wrapped in asbestos rope for safety, similar to the Sherman’s design. Also like radial engine Shermans, oil needed to be distributed to the engine through a hand crank to operate properly, requiring 70 revolutions, and it could be turned on with an electric starter after it was ready. The Nahuel had a respectable 14.28 hp/tonne ratio, which compensated for some of the drawbacks with the tank’s considerable weight and made it rather agile for its class, armor, and size. It had a range of 250 km or 155 miles, and could climb 30° inclines.
The frontal, hydraulic transmission was built by the Pedro Merlini company in Caballito, Buenos Aires, and had four forward and one reverse gears. The gear ratios are unknown, but it is possible they were also modeled after the Sherman’s, minus the fifth overdrive gear. The driver operated the tank using tillers.
The suspension was of the Vertical Volute Spring Suspension or VVSS type, with the front bogies noticeably stressed from the weight of the 80 mm front glacis. Per side, it had 3 bogies with 2 wheels each, a 12-teeth sprocket, 5 return rollers (3 of them attached to the bogies), and an idler.
The tank had 76 links per track, designed by technician Juan Carlos Moreno, and they were the last part of the tank to be finished, due to the difficulty of their development. They visually resembled the Sherman’s T51 treads.
Due to its rushed development and the Nahuel’s heavy weight, the track end connectors had a chance to pop off, throwing the track, although this was only a problem at higher speeds and in sharp turns. However, this issue affected the tanks inconsistently. Sometimes, while cruising, it could immobilize nearly all of them, while at other times, the tanks functioned without any problems. This possibly points towards crew mistakes with the track tensioning, and it is worth noting that the Nahuel had two sets of connectors, one external and another internal. Another alternative was that the track’s teeth were too short and wide to engage properly with the sprocket.
The Nahuel mod. 1944 was outfitted with Telefunken-designed radios, manufactured by the Fábrica Militar de Material de Comunicaciones [Eng. Military Factory of Communications Materiel]. The communications system was developed by the Argentine Navy, assisted by Baisi’s brother, Oscar. The exact Telefunken model is not known, but one source claims that it might have been a “TRD” or a 5 Watt Sender with a Type A receiver.
The only radio models bought from Germany in 1938, the last major arms purchase by Argentina before the Nahuel’s development, which the FMMC could have copied, were not specialized armored vehicle radio equipment, as they bought Lw.E.a and Kw.E.a station receivers and Torn. E.b infantry radios.
What the source most likely meant is that it was either a Torn. E.b or a 5 Watt Sender with a Lw.E.a. receiver. The most likely combination used in the Nahuel would likely have been a Torn. E.b with a 5 Watt Sender, which was a common pairing in the Wehrmacht, as the Lw.E.a was used with a 1500 Watt Sender. When used in armored vehicles, the Torn. E.b was known as the Fu.G. 1.
The Tornister Empfänger B was a radio receiver introduced in 1935, designed for foot soldiers of the Wehrmacht. It was a 4 valve radio (RV2P800 pentodes), used a 2 V and a 90 V battery, could tune to frequencies between 97 and 7095 kHz, and weighed 11.5 kg. It measured (L-W-H) 264 x 220 x 244 mm, and could receive continuous wave, tone, and voice signals.
The 5 Watt Sender was a radio transmitter introduced in 1934 and used along with Torn. E.b receivers. It was capable of operating in the frequencies between 0.95 and 3.15 MHz, utilized the vehicle’s battery, had a range of 36 miles for continuous wave and 10 miles for voice communication, and utilized 2 RS241 triodes. It was comparable to the SCR-284A set. Also present was an infantry telephone and an intercom for the crew utilizing photoelectric circuits.
Later Nahuel models featured the more widely known and tested Wireless Set No. 19. The WS No. 19 was a 15 valve transmitter-receiver radio designed in 1943 as a specialized AFV set. It utilized 12 or 24 V batteries, measured (L-W-H) 445 x 300 x 210 mm, weighed 18.2 kg, could operate between 2 and 241 MHz, and had a range of 16 km for voice and 24 km for continuous wave. This would be reflected by a second antenna mounting added to the turret.
Sources on the Nahuel’s history before 1947 are patchy, and as far as is known, the only service they saw was the 1944 parade, another parade on July 9th 1946, and a few small scale trials. It also seems that the Nahuel vehicles were assigned directly to the Escuela de Tropas Mecanizadas [Eng. School of Mechanized Infantry]. Due to the end of the Second World War, the Nahuel tank lost most of its purpose until 1946, when Colonel José María Epifanio Sosa Molina became the new Director de la Escuela de Tropas Mecanizadas [Eng. Director of the School of Mechanized Infantry].
Col. Epifanio Sosa Molina proposed to upgrade the Nahuel tanks, which needed refurbishment and had some design issues to fix, for example, regarding visibility and ergonomics. This project would have taken economic resources and effort which the Argentine authorities were not willing to easily hand over to the military. Luckily for Molina, he was held in high regard, and his brother, General José Humberto Sosa Molina, who held the position of Minister of War, managed to get his project approved.
At Sosa Molina’s behest, the Compañía de Tanques Medianos [Eng. Medium Tank Company] was created in 1947, equipped with the Nahuel tanks and supported by the Compañía de Tanques Livianos [Eng. Light Tank Company], equipped with Vickers tanks, both under the Escuela de Tropas Mecanizadas. In Arsenal Esteban de Luca, under Coronel Emilio Bidone, the Nahuel began its modernization, including a variety of quality of life upgrades.
Col. Sosa Molina was in charge of the Compañía de Tanques Medianos, and under him was the jefe de compañía [Eng. company commander]. Below that, two jefes de sección [Eng. platoon leaders] each controlled a platoon of five Nahuel tanks, supported by a oficial de mantenimiento [Eng. maintenance officer], and an encargado de compañía [Eng. platoon sergeant]. Per tank, there were two NCOs, the driver and the commander, along with the gunner, loader, and hull gunner/radio operator. In addition, there were three or four mechanic NCOs assigned to each platoon, in charge of both communication and automotive maintenance.
In order to avoid bickering within the military, the officers chosen to fill positions within the Compañía de Tanques Medianos were chosen from the infantry, artillery, and cavalry wings of the Army. Infantry Captain Julio Alberto Cáceres was assigned as company commander, who had previous experience as a mechanic NCO. The platoon leaders selected were Infantry First Lieutenant Héctor Pedro Nan and Artillery Lieutenant José Javier de la Cuesta Ávila, who were joined by Cavalry Sub-lieutenant José Humberto Sosa Molina as maintenance officer.
Interestingly, the reason the platoons were only equipped with five tanks and not six is due to only ten Nahuel being in service. The remaining two were kept in reserve or for spare parts. The officers were given Studebaker trucks but soon switched them for five Willys MB trucks with numbers EA 001-005.
While the Compañía de Tanques Medianos was being created, Lt. de la Cuesta Ávila, who unlike the other officers was not taking vacations or in need of reassignment, met Director Sosa Molina, and assisted with the refurbishing of the Nahuel tanks.
The remaining officers and NCOs were chosen among the best from the School of Mechanized Infantry, with their first introduction to the modernized Nahuel tanks in February 1947, when three of them entered the School. They were fascinated by the tank and, keeping in mind that at best the only tank they had seen before were the Vickers tanks, immediately and curiously began to inspect and interact with the tank, before Cpt. Cáceres gave them orders to stop. Even this was not enough, as some of the crews snuck out during the night to continue admiring them.
Soon, the company adopted guidelines to regulate all of its activities and even used the “Nahuel” song as its march. However, there were no manuals for the Nahuel, and thus, the officers had to use their own ingenuity and material from Esteban de Luca and the Sección Reglamentos [Eng. Guidelines Section] of the School. The Section let SLt. Sosa Molina, Lt. de la Cuesta Ávila, and 1st Lt. Nan take documents, but, as the officers soon found out, they were written in English, which led Lt. Nan to take up classes in order to translate the material for the rest of the officers. Between the three, they divided their roles as instructors, each being in charge of different subjects.
1st Lt. Nan’s research, along with his knowledge of the Infantry’s tactics, led him to implement the leapfrogging tactic into the platoons, including the command vehicles into the developing doctrine. Lt. de la Cuesta Ávila was in charge of finding out the best way to communicate, mount, and dismount from the tanks, along with teaching how to fire the tank’s gun. It was then that another of the Nahuel’s weaknesses surfaced. The optic mounts had a tendency of loosening up and drifting off-target, so he also took up aiming the guns using their bore, which seemingly worked well.
Lastly, SLt. Sosa Molina was in charge of teaching the tank crews to drive. He had by far the most complicated task, as he soon discovered the Nahuel’s track-throwing issues along with the subpar visibility for the driver and commander. Two accidents followed. During the first, one of the Nahuel tanks, while in its testing track, drifted in one of the final curves of the track, destroying a truck that had been hastily parked close by. After that, under Cpt. Cáceres, one of the tanks, while trying to mount on its carriage for transport, accidentally hit one of the brake tillers, crossing the tank across the truck’s rear and almost destroying it, only saved by the truck driver quickly disengaging the clutch.
Since the Compañía de Tanques Livianos was meant to work alongside the Compañía de Tanques Medianos, various officers were friends with the officers equipped with the Nahuel tanks and they shared quarters. The Vickers tankers likely unofficially knew how to drive the Nahuel as well. Baisi’s uniform was adopted, along with a new insignia, which would sadly last only for a year, being seen as too gaudy by General Benjamín Rattembach. They utilized garrison caps, brown jackets, and eventually, adopted the use of helmets that resembled cycling helmets.
With most of the training finished, the Nahuel tanks were shown off to the public again in a parade on July 9th 1947, three years after the Nahuel’s last parade. First, however, they had to be taken to their positions the day before the event. The route was rather straightforward. The tanks would start off from the crew’s quarters in Villa Martelli, go through Avenida General Paz, a large avenue, and then make their way to Avenida Figueroa Alcorta before stopping in front of the General San Martin Water Treatment Plant. The path was for the most part without any curves, but there were fears that the tracks’ end connectors would fall off, so it was planned to stop the tanks to hammer the end connectors back into place every 15 minutes. This was not needed however, as the trip was completed flawlessly.
On July 9th, the tanks made their way through Av. Figueroa Alcorta and then parked in a street parallel to Avenida del Libertador. There were fears that the engines would not start up in time for the parade, so any tanks that could not move were ordered to stay in place. The parade began, led by “c.121”, commanded by Sosa Molina, followed by the ten remaining tanks, and escorted by three Jeeps. The parade was a success, with no mechanical malfunctions reported, and the tanks safely made their way through Av. General Paz back to Villa Martelli.
Up to this point, as far as is currently known, the Nahuel had been involved in two public parades and several smaller scale military trials, including driving and firing range training. This all led up to the Nahuel’s biggest challenge, the final trials of 1947. These included a long drive, a combat trial, and a firing trial.
For its first task, the Nahuel tanks had to leave Villa Martelli through Avenida Zufriategui, taking the National Route 9, and make their way to a plot of land on the outskirts of San Miguel, part of a Jesuit seminary. They commenced their journey the day before the trials were to take place and had one stop before arriving at the location, the Liceo Militar General San Martín [Eng. General San Martín Military Lyceum].
Sadly for the Nahuels, this first test was a failure. Only one tank arrived at the Liceo Militar in the first 30 minutes of the trip, while the other 9 took 6 hours, with the first half of the trip finished by 3 PM. After letting the cadets appreciate the tanks, the tracks were inspected and presumably fixed. The tanks arrived at their final destination in the afternoon. The Jesuits came to help the tankers with cleaning the tanks, and one of them, José Sponda, assisted the mechanics and even managed to drive the vehicle back and forth briefly. After that, they ate with the Jesuits and were sent to the Escuela de Artillería [Eng. Artillery School] to shower, an uncommon luxury for the crews.
The next day, the combat and firing trials took place. The combat trial was first, in charge of Lt. Nan and planned by Cpt. Cáceres, assisted by Major Enrique Oyharzabal Castro, who explained the exercises to the crews. The Nahuel’s biggest issue was visibility, since the tanks had to do the trials fully “buttoned up”. Nan and de la Cuesta Ávila, unbeknownst to Cáceres, came up with a cunning plan to fix this issue. Well camouflaged soldiers would lead the tanks, with other soldiers throwing smoke grenades to cover the battlefield. Once the tanks started moving, most of the officers watching the trials did not see the trick being played, except for Lieutenant Colonel Lorenzo Toselli, who decided not to report it. The tanks fired blank shots from their machine guns and gun, covering the battlefield with enough smoke that some drivers could also peek through the hatches unnoticed.
Next, under de la Cuesta Ávila, it was the turn of the firing trials, which were also to be done in front of a crowd. The Nahuel tanks had a simple task: enter the firing range, stop, shoot at targets, and then continue moving. However, due to the Nahuel’s unreliable optics that went off zero constantly, de la Cuesta Ávila gave each tank commander a mirror to let them use the tank’s bore as a sight. Toselli, again, thought that this was set up in advance, and the tanks were firing blanks, with the targets exploding on their own, but save for the improvisation with the aiming system, the exercise was carried as intended, and the crowd applauded the tanks after they successfully destroyed the targets.
The Nahuel tanks then returned to the Escuela de Tropas Mecanizadas, having “passed” the trials through some trickery and improvisation, but to the military authorities and to the commanders, it was an absolute success. However, even in its most glorious moment, the Nahuel’s days were numbered, as Sherman tanks first arrived in Argentina the same day, and soon would replace Argentina’s indigenous medium tank.
After the end of the Second World War, Brazil obtained a large amount of surplus equipment from the United States and Argentina found itself even more outnumbered in terms of armored vehicles. To remedy this, AFVs were purchased from Europe. On December 14th 1946, war material from the British Army was purchased for US$36.5 million from Belgium as “junk” to avoid the ongoing arms embargo placed on Argentina. This deal included 154 M4A4s, 205 Sherman Fireflies, 280 T-16 carriers, 379 half-tracks of various American designs, and 120 Crusader tractors, for a total of 1,138 AFVs, along with various other trucks. They arrived in 1947, and despite their classification as junk, some of the material arrived in perfect condition, with the T-16 carriers still in their original shipping crates.
The next day, the Nahuel tanks were stored in their sheds, and the crews tested the Sherman, with its handling familiar to the Nahuel’s crews due to their prior experience. According to its crews, the difference between the Shermans and Nahuels was the same as the difference between driving an old tractor and a modern car, as the Shermans were far easier to handle and had less design issues. The Shermans that arrived were either Fireflies or M4A4s, with some later purchases of the M4A3 type, which widened the quality gap between the tanks.
In 1948, the Nahuel tanks were transferred to DGME for storage along with some of the new AFVs imported for Argentina. Some made the trip under their own power. In 1959, General Manuel Ángel Ceretti overlooked the scrapping of the remaining 10 Nahuel tanks, and again, some Nahuel tanks were still in driving condition. Some pictures of their sad fate have survived.
Georg von Rauch claims that President Juan Domingo Perón donated 2 Nahuel tanks to Paraguay in 1953 , but it was later proven that these were T-16 Carriers and not medium tanks. One Nahuel, “c.122”, was converted into a monument, with the front glacis removed. It was attached to the Grupo de Artillería Blindado 1 [Eng. Armored Artillery Group 1] in Campo de Mayo. The Grupo de Artillería was relocated to Curuzú Cuatiá in Corrientes, however it is unknown what happened to the statue afterwards.
Modernizations and Variants
Nahuel Reciclado/Nahuel I mod. 1947/Nahuel Sosa Molina
By 1947, the aging Nahuels needed some quality of life improvements. They were in dire need of a refurbishment after continuous use, and by the suggestion of Director Sosa Molina, the tanks were sent back to Arsenal Esteban de Luca to get an upgrade to increase their battle-worthiness, with lessons learned from the late-war Shermans. This modification would be termed “Nahuel Reciclado” [Eng. Recycled Nahuel].
The hull underwent large modifications. Two of the hull machine guns were removed, the holes being either filled in or welded shut. A new vision block for the driver was added, which could be slid to the side to increase visibility. The open headlights, originally vulnerable to damage, were armored, with a slit for the light to come out from.
New hatches were added, articulated horizontally and vertically. This was due to an incident in which, during testing, an officer intended to ram a wall with a Nahuel tank and traversed the turret backwards to avoid damaging the barrel. However, the turret had a short bustle which blocked the hatch from opening normally. The upgrade allowed for increased awareness when the tank was not “buttoned up”, and made access far easier.
The turret was also modified, with the 11.35 mm Madsen coaxial machine gun replaced with another 7.62 mm Madsen, possibly for logistical purposes. The turret’s sides were provided with more attachment points for the tracks. Furthermore, the hull’s stowage was revamped, with most of the tools being stored at the rear of the tank’s sides, improving the use of space, and the middle section was converted to hold tracks. The characteristic jaguar drawing on the side of the hull was also removed.
Finally, the Telefunken radios were replaced with the purpose-built British Wireless Set No. 19 Mk. III, bringing communications equipment to a modern level, and this could be seen from the outside with the addition of another antenna mount in front of the old mount.
Nahuel with Bofors mod. 1935/Nahuel II
At some point during the Nahuel’s development, an idea was brought up to rearm the Nahuel with the Bofors 75 mm L/40 mod. 1935 cannon. This would have given the Nahuel a capable gun, equal in characteristics to the 75 mm Shermans in service, which along with the 1947 modernization would have made it even more front heavy than originally designed.
A small number of military personnel said in interviews that one Nahuel had been tested with the Bofors mod. 1935 cannon. However, it is thought that these are just barracks rumors, and no pictures or reports have surfaced of this up-gunned Nahuel.
The Nahuel’s misfortunes did not stop with the scrapping of the few tanks manufactured, as it has gone through a sad legacy, being largely forgotten by the Argentines and seen as an inferior Sherman knock-off by the international community. A lot of it comes from conflicting sources, misinformation, and the burning of the Nahuel’s archives, which led to it being relegated to obscurity and dismissal.
This is hardly a revisionist idea, as even at the time it had been the victim of the same mistrust and misinformation which led to its tarnished legacy. During the July 9th, 1944 parade, one civilian addressed the public and alleged the tank was made out of cardboard, to which one NCO had to prove it was made out of metal by banging the civilian’s hand on it. The United States thought it was made out of salvaged plates. Even the people in charge during its service seemed to underestimate its capabilities, which led to the Nahuel performing beyond what was expected of it.
Its combat capabilities were on paper adequate for the time, given that during much of the 1940s, its only real opponents were Peru’s LTPs and Brazil’s M3 Light Tanks, M3 Medium Tanks, and M4 Medium Tanks, which would have been either inferior or comparable in characteristics. The tank was not without its faults, however.
The Nahuel’s automotive reliability issues in the design of its tracks meant that it would have been better suited for use in the Pampas or Argentine plains and of questionable utility for an offense against Argentina’s neighbors. The limited visibility for the crew, especially the driver, was an issue during trials, although it was overshadowed by the far bigger problem of optics which could not keep zero, and its obsolete main gun.
The biggest issue with the Nahuel was not any of its intrinsic design choices, it was its production capabilities. The Nahuel project took a huge effort from Argentina to complete, it was not a tank meant for mass production, and it would have been costly to manufacture more tanks. The small amount produced could not match Brazil’s larger number of available combat vehicles.
On the other hand, its design was far from short sighted or antiquated, with the welded, simple, heavily armored hull and accessible transmission being advantages of its design. The crew had a large workspace, and the upgrades managed to ameliorate some of its biggest issues. It was also maneuverable and could keep up the pace with the Sherman tanks. The resulting vehicle was, on paper, a decent tank with a lot of potential for 1940s South America, and had it not suffered from political instability and unfortunate timing, it could have been upgraded to higher standards, as the platform had room for improvement.
The Argentines’ naivety, creativity, and ability to improvise was evident through its design, development, trials, and service. In the Armor School in Fort Knox, the Americans praised Argentine soldiers for their ability to improvise with the resources they had, receiving high scores among students from other nations, including Brazil, France, the United Kingdom, and others. Baisi, his design team, and later Sosa Molina, had built a medium tank comparable to the Sherman, in a country with no true tank building experience, and laid the foundations for Argentina’s future incursions into tank design.
There have been efforts to find an intact Nahuel tank that may have survived scrapping. The closest to a Nahuel in existence is a statue in Tecnópolis, seemingly modeled after it.
Special thanks to Ricardo Jorge Sigal Fogliani for providing bibliography, material, and information necessary to make this article, it would have been impossible without his help and research. And special thanks to Iván Dubaniewicz (COLDOWN) for assisting in the research of the tank’s components.
|Tanque Mediano Nahuel Specifications|
|Dimensions (L-W-H)||6.233 x 2.33 x 2.952 m (20.416 x 7.64 x 9.685 ft)|
|Total weight, battle-ready||35 tonnes|
|Crew||5 (driver, co-driver/hull hunner, hunner,loader/radio operator, commander)|
|Propulsion||Lorraine-Dietrich 12 Eb W-12, 12 cylinders, 493 hp at 2,500 rpm (367.75 kW)|
|Speed||Roads: 40 km/h (24.8 mph)|
|Range||250 km (155 mi)|
|Power to weight ratio||14.28 hp/tonne|
|Transmission gearing||4 forward (1-2-3-4): 7.56, 3.11, 1.78, 1.11
1 reverse: 5.65
(Gear ratios from M4A1 Sherman minus fifth gear)
|Armament||Primary: Krupp mod. 1909 L/30 75 mm cannon
Coaxial: 1 x Madsen 11.35 mm HMG (mod. 1943)
1 x Madsen 7.65 mm LMG (mod. 1947)
Hull: 3 x Madsen 7.65 mm LMG (mod. 1943)
1 x Madsen 7.65 mm LMG (mod. 1947)
|Elevation and traverse||(Krupp 75 mm cannon): 360° traverse, unknown elevation|
|Gunsight||Goertz periscopic sight, 4x magnification, 10° FOV|
|Armor||Hull: 80 – 10 mm
Turret: 80 – 10 mm
|Communication||Torn. E.b. (Fu.G. 1) / 5 Watt Sender (mod. 1943)
Wireless Set No. 19 Mk. III (mod. 1947)
|Production||12 + 1 wooden mock-up|
Ricardo Jorge S. Fogliani, Blindados Argentinos, de Uruguay y Paraguay.
Ricardo Jorge S. Fogliani, Nahuel DL 43.
Georg V. Rauch, Sabor Criollo. El Nahuel D.L.43.
Georg V. Rauch, El Tanque Nahuel DL-43.
DIA, Small Caliber Ammunition Identification Guide, Volume 2, 20-mm to 40-mm cartridges.
Escuela de Artillería, Recuerdo de mi Vida Militar
Departamento Munición y Química de Guerra, Catálogo de Granadas y Proyectiles.
War Department, TM-E 30-451.
Image credit to Victor Eduardo Barbanete, COLDOWN, Ricardo Jorge Sigal Fogliani, militariarg.com, and Georg von Rauch.