PIBWL Polish Armour page Main page » Polish armour » armoured cars » wz.29 Ursus   – Polish artillerySteel Pantherswhat's new Samochód pancerny wz.29 - po polsku
  © Michal Derela, 1998 Updated: 3. 4. 2024  

Polish armoured car wz. 29 Ursus


History
Combat use
Description
Camouflage
Specifications
Models
    Part II:

Gallery
Wz.29 armoured car on a parade.

The armoured car wz. 29, known also by the chassis manufacturer name as the Ursus, was the heavier type of Polish armoured car from the interwar period, used in only one out of 11 reconnaissance armoured units. In spite of being obsolete by September 1939, slow and attached to roads, a handful of these cars acted in combat surprisingly well, serving in the 11th Armoured Unit of the Mazowiecka Cavalry Brigade and fighting with enemy armoured vehicles with some success.

Note: links in a text without an underline lead to Wikipedia articles.


History

Produkcja i ocena

Wz. 29 armoured car prototype
The armoured car wz. 29 prototype, with an early rejected turret, with both machine gun mountings opposite to a cannon. There are also minor differences in hatches. The car has an old four-colour camouflage, used from 1928, and truck tires.
Modified wz. 29 armoured car prototype
The modified prototype as a pattern vehicle. Visible are semi-solid Overman tires and CWS badge, seen only on this example. The car has an uniform camouflage and an original placement of weapons, reversed in comparison to a final standard.
Early wz. 29 amoured car photograph
The armoured car no. 6753 in an early shape as above, with an additional upper machine gun mounted.

In early 1929, the Polish Main Staff, being not quite satisfied with the newest halftrack armoured car wz. 28, ordered to develop a new armoured car for the Cavalry. The new car was designed in Military Engineering Research Institute (Wojskowy Instytut Badań Inżynierii, WIBI) by a team directed by Lt. Rudolf Gundlach, later known as the inventor of a reversible tank periscope (popularized in the world as Vickers Tank Periscope Mk IV).

In order to simplify a design and maintenance, it was decided to use a modified commercial chassis of Ursus A 2-ton truck, which originally was the Italian SPA 25C, manufactured under licence and further developed from 1928 in "Ursus" Mechanical Works in Warsaw. Assessing Polish capabilities, it should be remembered, that Poland was partitioned for over a century before World War I, and (unlike in neighboring Czechoslovakia) none of occupants was eager to promote a serious machine or automotive industry there. As a result, it had quite weak industrial base at the outbreak of 1920s, and Ursus A was the first truck manufactured in Poland, and the only available at that time. Modifications to the chassis were limited: a frame was shortened behind a rear axle, and a front suspension was strengthened. A necessary requirement set by the army was to equip the car with a rear driver's position to enable quick withdrawal from under fire (and, in theory, also to attack with the rear forward).

The prototype of the armoured car, number 6477, made of ordinary boiler steel, was ready on 10 March 1929[8]. It had the same body shape as later production cars, but differed mainly in an arrangement of weapons in the turret opposite to each other, and the rear machine gun located lower. From 11 June 1929, shooting tests were carried out, and from 28 June, there was a test raid on Warsaw - Zakopane route and back (approx. 1,000 km). As a result, improvements were introduced, mainly placing weapons in the turret not in one line, raising the rear machine gun position, adding observation hatches in the front wall on the left and in the left wall at the rear, and enlarging side engine service hatches. The improved prototype was received on 10 October 1929, and in the same month it took part in maneuvers in Rava Ruska area. They showed that the car met the requirements and it was accepted as a model for a production. The car was accepted with an Army designation: samochód pancerny wzór 1929 (in short: wz. 29) - armoured car 1929 Pattern; additionally referred to as "Ursus brand" in military acceptance protocols. It was commonly known as Ursus; also referred to in documents with the abbreviation: "U".

Tests of the prototype showed that despite advantages such as strong armament, sufficient and well-shaped armor, and a rear driver's post, making driving backwards easier, the car had significant faults. They were primarily: low speed, especially backwards, poor maneuverability and an inability to move off-road. Moreover, the engine used was an old design, from before World War I, with low power output (35 HP). The commercial chassis with truck engine and transmission reduced a cost of development and production, and a lack of all-wheel drive was typical for most armoured cars of that period, but the consequence was the lack of off-road properties, which limited the car's use to roads. Moreover, a conclusion from 1929 maneuvers was, that in autumn and spring, when dirt roads turned to mud, cars could only drive on roads. Dirt roads with larger slopes were also a problem. It was pointed out that the car was also quite a large target, although it should be noted that its silhouette was in fact not larger than other medium armoured cars of that period. However, in spite of quite big silhouette, there was not much room inside, due to high chassis frame (height of a crew compartment was only up to 1.1 m – 3.6 ft). Both the armament and its arrangement soon became obsolete - the short-barreled 37 mm cannon had little anti-tank capabilities, and Hotchkiss wz. 25 machine guns were unreliable. It all caused, that the design could not be called a modern one at a time of entering service. Comparing the car wz. 29 to other vehicles of that period, its strong point was its cannon armament, even a weak one (not all other armoured cars had cannons), and armor, which put it at the forefront in terms of thickness and shape, while its main shortcoming was its lower speed than most designs[note 1]. Moreover, already in the first half of 1930s, better armed armoured cars with better off-road mobility were being constructed.

Production and evaluation

Because of these drawbacks, only 10 cars for one company were ordered on 20 March 1930 in PZInż national concern (State Engineering Works). The cars were buit upon Ursus chassis delivered by the Army in Państwowa Wytwórnia Samochodów in Warsaw (State Car Factory, merged into the PZInż in 1928, still using CWS brand of former Centralne Warsztaty Samochodowe – Central Car Workshops). Armour plates were delivered by Bismarck Ironworks (later Batory Ironworks) in Hajduki Wielkie (later Chorzów). The cars were delivered to the Army in three batches between December 1930 and February 1931. The armouring of a single car costed 76,450 złoty ($8590) – without a complete chassis, armament and periscopes delivered by the Army, while the chassis costed some 17,000 złoty ($1910). Therefore, the car costed around $10,500, without periscopes and weapons from Army stock. Older publications quoted erroneous too small price of the car (36,000 zł). The cars were first unarmed, because 10 sets of new ball weapon mountings were delivered only on 14 April 1932 (the prototype car had prototype mountings as well). The number of wz. 29 cars built was not sure in older publications, and a number of 13 cars was also quoted. Only in 2019 a new generation of authors researched documents and established a number of 10 series cars and their numbers (6571, 6590, 6604, 6608, 6628, 6753, 6754, 6755, 6798, 6769)[7,8]. The 11th car was the prototype 6477, taken over by the Army on 20 May 1930, but it was made of a regular boiler steel, fit for training only. At least five more cars were planned, but the Army abandoned these plans.

Wz. 29 armoured car
The prototype of wz. 29 armoured car with an original weapon arrangement and the turret slightly turned right and both main weapons heading forward and rearwards thanks to a big angle of movability in ball mountings. The turret has not all vision slots yet, but it also has some fake ones painted.
Wz. 29 armoured car
A production car, still unarmed (before mid-1932). Well visible is a stowage of tools.
An Ursus in a washable winter camouflage on exercises near Przemyśl and Lviv, March 1934. A rear machine gun is dismounted. Noteworthy is usage of tire chains. The car has tactical markings of the second in platoon command.

The design was fairly typical for the 1920s. It should be noted, that at the moment of designing there were actually no clearly better armoured car designs in the world[note 1]. It had a rear-drive only, a crew of four and was armed with 37 mm Puteaux SA low-velocity gun and two Hotchkiss machine guns, mounted in Polish-designed ball mountings. It was influenced by some features of World War I-era British/Russian Austin armoured cars (second rear driver post) and French White TBC cars (a turret with two same weapons in opposite sides). An arrangement of armament helped avoid problems with turret balance, and was a bit better, than in the French car (main weapons were placed at angle of 135° to each other instead of 180°), but it made difficult shooting both weapons at one target alternately anyway. The first vehicle in the world with real coaxial weapons in common mounting was Vickers Mk.E Type B tank of 1930. Some other early designs utilized two independent weapons in forward turret part, like Soviet BA-27 armoured car, but it should be noted, that Soviet DT tank machine gun weighted two times less and was more compact than infantry Hotchkiss – which was not optimal for armoured weapons. The wz. 29 car was unique in the world due to its arrangement of weapons: a rear machine gun and a turret with three weapon mountings in different sides, including the third upper weapon mounting. A machine gun in the upper mounting is usually considered an anti-aircraft, but already during prototype trials it was found ineffective in this role, and the mounting was retained first of all in case of firing at higher floors during urban combat (aiming at aircraft was impractical with telescopic sights with a limited field of observation). In case of need, the turret MG could have been mounted in the upper mounting.

A capability of conducting reconnaissance was limited by a lack of a radio – its use would require solving the problem of screening of the engine's electrical installation, although in 1931 tests of Polish RKD wireless set were carried out on one vehicle. Its range was 20 km for telegraphy and 4 km for voice transmission. Other armoured cars of that period usually did not have radios either, but it was going to change in mid-30s.

Apart from difficulties with alternate usage of turret weapons, a rear-facing machine gun post with a dedicated crewman did not seem to have much practical use, especially that the rear driving post was added just in order to avoid complicated turning back on country roads. There was no possibility to place a machine gun in a front plate next to the driver without a major redesign, because due to the length of the Hotchkiss machine gun, its gunner would interfere with the commander in the turret. It was envisaged that the car could attack backwards, when it could fire two weapons, but this was obviously a mere theory, especially due to the low speed rearwards (maximum 17 km/h for a short period). The car's purpose was a reconnaissance, not supporting attacks, anyway. It should be noted however, that rear-facing only machine gun was also used in later Italian modern Autoblinda AB 41 armoured car, while bow mounted machine guns were not very common in armoured cars. Further assessing the design, the rear driver's post was a good solution, but its advantages were limited by a lack of a reversing gear that would enable driving at the same speed as forward. The postulate of increasing the reverse speed was raised after the prototype tests and a work on redesigning the gearbox was started, but apparently it was ultimately abandoned. Undoubtedly it was quicker and cheaper to use an existing commercial gearbox, which was a decisive factor. On the other hand, using a truck rear axle with a double reduction gear made the Ursus slower then other armoured cars with similar engine power. The modernization of vehicles by replacing the engine with a newer one, e.g. Fiat 122 (46 HP), indicated as a missed chance in part of modern publications, must however be assessed as unrealistic, taking into account the significant interference in the chassis structure, with a marginal significance of produced cars for Polish Armoured Weapons. In the world, modernizations of this type were carried out mainly by replacing the entire chassis, in case of its wear (eg. in French White-Laffly AM 50). There are no hints, that any modernization of wz. 29 cars was considered anyway. It may be interesting to compare the Ursus with the Czechoslovak Škoda OA vz.27 car built on a special chassis, which was heavier, had thinner armour of a complicated shape, did not have a cannon, and despite a sophisticated drive system, had effective rear-wheel drive in both directions, and it was more than twice as expensive ($25,000).

Related developments

Ursus propaganda car
Ursus propaganda car of the 5th Armoured Battalion
Wz. 31 armoured car project
Projected wz. 31 armoured car (drawing: J. Magnuski)

One or two Ursus trucks were completed as unarmoured propaganda cars, externally similar to armoured cars, fitted with loudspeakers in turrets. Such cars were used to play music and commentary during military parades. Earlier publications speculated, that they might have been police vehicles, converted from wz. 29 armoured car prototypes, and only in early 21st century their role has been properly researched. A longer body, made of regular steel plates or even plywood (as suggested in a description of the car of the 3rd Armoured Battalion), indicates usage of an ordinary unmodified truck chassis. There are known photographs of two different vehicles, one with number 6814 (in mid-1930s), and one without a number visible, used in late 1930s in the 5th Armoured Battalion in Kraków. The car 6814 might have been used in the 3rd Armoured Battalion in Warsaw. Less probable version is that it was only one rebuilt car. More photographs are in part II.

In 1930-31 there were carried design works upon a successor using Saurer 6x4 chassis, which was meant for a production in Poland. It is known under a preliminary designation: wz. 31 armoured car. An intended engine was Saurer petrol 100 HP or Saurer BLD diesel 85 HP (a variant of the latter was next used in the 7TP tank). The car wz. 31 copied the wz. 29 layout, offering greater speed and only slightly better off-road characteristics, for a bigger silhouette, the same obsolete armament, and almost twice as big cost, so the project was cancelled before a detailed design. The price was estimated at 160,000 złoty ($17,978), including 61,000 złoty for the chassis ($6854). Combat weight was to be 7.8 t, overal length 7 m (with the machine gun).

It might be noted, that the car would have a similar silhouette as later German SdKfz 231 6-Rad, but with a disproportionately long engine hood and axle span. A very big axle span obviously would have made off-road driving difficult, especially without 6x6 drive. It was a side effect of taking another commercial heavy truck chassis, with a heavy engine in addition (800–1000 kg). Possibly on a later stage the chassis might have been shortened, because the engine did not need such a long space. Further development might have led to an adoption of 7TP-style Bofors-designed turret with 37 mm Bofors gun, resulting in a car similar to Swedish Landsverk designs (used by the Netherlands). Also a turret with 20 mm automatic cannon from the 4TP prototype tank might have been fitted. However, this project can hardly be considered a promising vehicle for the Polish Army in terms of cost/effect, and it would only have a chance of being equipped with valuable weapons at the very end of the 1930s, being not much cheaper than the tank.

It is noteworthy, that the turret designed for the armoured car wz. 29 found much wider usage. Such turrets in an original shape, with a slanted upper plate, but unarmed, were adapted on three armoured locomotives Ti3 class of the 2nd Armoured Train Unit in Niepołomice (armoured trains: Nr. 51 "I Marszałek", Nr. 52 "Piłsudczyk" and Nr. 53 "Śmiały"), as an observation and command turret. Weapon mountings were replaced by two-leaf doors covering round observation hatches, and at least one new rectangular hatch was made. They were to be fitted with observation devices for directing of artillery fire. A provision for mounting a light machine gun wz. 28 Browning, carried in a command compartment, was proposed in 1937, but it is not clear if it could have been fitted eventually. Such turret was also used in a prototype armoured diesel locomotive. It was envisaged to mount such turrets in 9 modified Tatra armoured draisines, but they were not built eventually. It is not clear, whether turrets used in armoured trains came from partially cancelled order for armoured cars, which is not known so far, or they were ordered independently.

A modified turret was appreciated by the Polish Navy, which called it the Ursus type turret (despite Ursus works had nothing to do with the turret design). It had no slanted upper plate and no ball weapon mountings. The main armament was the same 37 mm Puteaux SA cannon, but mounted higher in a rectangular Cardan mounting. In a side plate to the left of the gun there was a vertical covered aperture for 7.92 mm Maxim wz. 08 water-cooled machine gun, which could have been used as an anti-aircraft weapon due to a high elevation angle. Such turrets were used in riverine flotilla craft: a heavy armed craft ORP "Nieuchwytny", three riverine gunboats Z class (ORP "Zuchwała", "Zawzięta" and Zaradna") and nine rebuilt light armed craft: KU 16–19 and 25–29. Contrary to most publications, riverine minesweepers T 1 to T 3 had no turrets, though.


A platoon of wz. 29 cars from Bydgoszcz in 1935, wearing an early camouflage. The commander's vehicle has number 6628. A triangle on a front plate means the second platoon. A platoon of cars wz.29, wearing an early camouflage

Combat use

A wz. 29 car no. 6604 in 1932–1934. The car has Overman tires and uniform protective colour.
Wz. 29 cars on a parade in Warsaw on 5 August 1934. Well visible is an exhaust pipe position. More photographs in a gallery.
A wz. 29 car in late 1930s, in a final camouflage, in wartime-like appearance (the pattern vehicle, with CWS logo).
Armoured car wz.29.
A wz. 29 armoured car on a parade in Warsaw on 11 November 1936.
Probably the Ursus destroyed on 3 September 1939 near Chojnowo. More photographs in a gallery.
The Ursus destroyed on 12 September 1939 in Seroczyn.
An abandoned Ursus, probably in Rudka (now Zwierzyniec). It is noteworthy, that it still has Overman tires on a rear axle.

Before the war:

In the 1930s, Polish Armoured Weapons became an independent branch, and armoured units were reorganized several times. The first platoon of three wz. 29 cars was assigned in 1931 to the Experimental Armoured and Motorized Group in Modlin fortress, with which the fate of Ursuses was tied up until the outbreak of the war. A squadron of next eight cars, commanded by Capt. Józef Zasadni, was first meant to be stationed in Lviv, but eventually joined the 2nd Armoured Car Unit in Żurawica near Przemyśl. From 1 September 1931, they constituted a squadron of road armoured cars of the newly established 2nd Armoured Regiment. It should be noted, however, that it was only in mid-1932 that production cars were armed

Three armoured cars remained in Modlin, included with the Experimental Armoured and Motorized Group into the 3rd Armoured Regiment. They were used during the cavalry manoeuvres near Lviv between 17 August and 10 September 1931, in order to evaluate the vehicles (along with 10 tankettes Carden-Loyd MkVI and 15 newest tankettes TK-3). The conclusion was, that the cars were not fit to accompany the cavalry, especially in terrain conditions of rural eastern part of Poland, where most roads were dirt ones. One car, probably the prototype, was experimentally fitted with radio then.

After reorganizing regiments into armoured battalions in 1934, a platoon of cars from Żurawica was included into a separate armoured car company (along with old Peugeot cars), sent in March 1934 westwards to Poznań (subordinated to the 1st Tank and Armoured Car Battalion), and finally on 17 December 1934 to Bydgoszcz (subordinated to the 8th Armoured Car Battalion). There were cars with numbers: 6604, 6608, 6628 and 6755. There is no information about this in publications, but we can assume, that the remaining cars from the 2nd Armoured Battalion from Żurawica had already been transferred to the Experimental Armoured and Motorized Battalion in Modlin (which is supported by the presence of seven cars at the parade in nearby Warsaw in August 1934). Finally, by the end of 1935 all wz. 29 armoured cars found themselves in Armoured Weapons' Training Center (Centrum Wyszkolenia Broni Pancernych, CWBrPanc) in Modlin, where they were assigned to the experimental 11th Armoured Battalion. In July 1939 eight were counted as category B (fit for training and mobilization), and two (or three) as category C (worn out, fit for training only)[note 2]. Pre-war peacetime Armoured Battalions (batalion pancerny) should not be confused with later wartime mobilized battalion-size armoured units.

In late August 1939, during a mobilization, 8 cars were included into the newly formed 11th Armoured Unit (11 Dywizjon Pancerny), assigned to Mazowiecka (Masovian) Cavalry Brigade of the "Modlin" Army, as its reconnaissance unit. Seven cars formed the armoured car squadron with two troops, the eighth car was the unit's commander's, who was Maj. Stefan Majewski. The armoured car squadron commander was Lt. Mirosław Jarociński, armoured car troops' commanders were Lt. Michał Nahorski (first troop) and WO Stefan Wojcieszak (second troop) (see a map for an initial deployment).

September 1939:

Just from the first day of the war with Germany, armoured cars and tankettes of the 11th Armoured Unit were intensively used for reconnaissance and patrolling, bringing information about the enemy. Soon their main task became delay actions and securing a withdrawal of Polish units from predominating and encircling enemy. In several cases they supported Polish attacks. The combat track of these few obsolete machines was surprisingly, relatively successful, mostly due to their cannon armament. Here are main episodes of the combat track of the 11th Unit's armoured car squadron:

On 1 September 1939, at the war outbreak, two armoured car troops were assigned to outposts of Mazowiecka Cavalry Brigade, in front of main defence lines, by the border with East Prussia. From the first hours, the 2nd troop was firing at advancing Germans from road ambushes. In the evening, it laid an ambush near Krzynowłoga Mała village, and destroyed all three German light armoured cars from a reconnaissance unit of the 12th Infantry Division. Two Ursuses were damaged and WO Wojcieszak was hurt in a head, but continued combat service.

On 3 September one car was lost in a skirmish with armoured cars of a troop (Panzerspähtrupp) "Poetschke" from SS Reconnaissance Unit of "Kempf" Armoured Division near Chojnowo village (between Przasnysz and Grudusk), when the troop was sent to make a contact with Polish 8th Infantry Division. Later that day, all the armoured car squadron supported the 11th Uhlan Regiment, repelling attacks of the 3rd battalion of SS "Deutschland" motorized regiment from this division in a forest near Przasnysz.

On 4 September, the 1st troop supported the 7th Uhlan Regiment in a skirmish of Szczuki village (near Przasnysz). Polish cars destroyed two tanks, probably PzKpfw I of a platoon, which was trying to go round Polish uhlans' positions. Around 3 pm, Lt. Nahorski destroyed enemy staff car of Maj. Otto von Korwin-Wierzbicki from the 1st Cavalry Brigade, with a gun shot, capturing maps and documents (unfortunately, enemy plans were misinterpreted and contributed to wrong decisions of Polish C-in-C in following days, leading to a collapse of the northern front).

On 7 September, Ursus cars, supporting the attack of the 7th Uhlan Regiment at Długosiodło village (near Ostrów Mazowiecka), destroyed another two enemy armoured cars from the 1st Cavalry Brigade. According to older publications, one ursus was lost[4], but this information was not repeated in newer publications, also of the same author. The unit went to the Brigade reserve for a few days then.

On 12 September, the armoured unit was moving to join its cavalry brigade. In the morning, it incorporated two light armoured cars wz. 34, separated from the 61st Armoured Unit. One of these cars was later taken by the squadron commander, who gave his Ursus to combat troops. After 9 am, just behind Seroczyn village (south-east of Warsaw), the 1st armoured car troop, moving north in a vanguard, encountered a vanguard unit of Kampfgruppe "Steiner", detached from "Kempf" Armoured Division. The German unit consisted of a motorcycle company with an armoured car troop, four anti-tank guns and four infantry guns. In a short skirmish, two enemy armoured cars were destroyed, but one Ursus was also lost (hit by an anti-tank gun), and the Polish unit withdrew to the village. Soon the enemy deployed its forces, and entered Seroczyn, rejecting the Poles southwards behind the Świder river.

Before the second stage of the meeting engagement, Maj. Majewski formed a group of his armoured unit, all loose soldiers gathered nearby, an artillery battery found in a forest without horses, and also newly arrived 62nd Independent Reconnaissance Tank Company with TKS tankettes. The Poles launched an attack across the river, but it failed. Armoured cars attacked straight through the bridge, but the first Ursus that crossed the bridge was hit by an anti-tank gun, while the tankettes on the right wing stuck on boggy meadows. Then, main Kampfgruppe forces, with tanks from the 6th company of the 7th Panzer Regiment, supported by artillery, forced weaker Polish unit to withdraw to south-west around 13 pm. Polish losses in all that engagement were two wz. 29 cars, one wz. 34 car, and several tankettes. It is however not clear, that photographs indicate, that one Ursus was destroyed near Latowicz borough, some 2-3 km west of Seroczyn[note 3]. The Germans suffered some losses as well, and their advance towards the Vistula was halted for some time (enabling a cavalry group of Gen. Władysław Anders to withdraw through a gap). The 11th Armoured Unit then moved south to Garwolin. It however lost part of its maintenance platoon, which had separated in Seroczyn and moved other way.

In the evening, the 11th Armoured Unit, moving towards Dęblin, had a skirmish with a reconnaissance unit of German 1st Infantry Division, on a crossroad near Gończyce village. The Germans were rejected from the crossroad and Polish unit broke through, but it lost the commanders' wz. 34 armoured car, which was hit by a mortar shell and put on a fire (the crew bailed out unharmed). According to Maj. Majewski, the unit still had two Ursus troops then (the first with three cars, and the second presumably with two cars).

At last, the weakened armoured unit joined units of the "Lublin" Army in Lublin on 13 September. Maj. Majewski was given also a command upon elements of other Polish armoured units there (a company of the 1st Light Tank Battalion with 7TP tanks and the 33rd Armoured Unit). On 14 September Ursus platoon conducted a reconnaissance from Piaski Luterskie towards Krasnystaw. According to the unit's commander, they drove away German armoured cars there. On 15 September, Maj. Majewski's group was incorporated into an armoured core of the Polish concentration there – Warsaw Armoured-Motorized Brigade (WBP-M). Unfortunately, last armoured cars had to be destroyed on 16 September near Zwierzyniec, because they could not move farther through sandy and rough forest roads to the south-east of Lublin (reportedly they were sinking in sand up to their axles). The second thing was, that Polish tankettes and Vickers tanks needed all the petrol left for the last battle of Tomaszów Lubelski on 18 September.

Some of cars wz.29 could have been repaired and used by German police in an occupied Poland, but there is no such evidence.

None of cars wz.29 survived the war. A driving mock-up was built in the 2000s, clearly different, especially in a longer rear part (built upon a longer truck frame), and in primitive imitations of weapons and their mountings.

Part II: A gallery with additional photos and information on armoured car wz. 29


Description

Armament

37 mm SA cannon of a destroyed wz.29 car
37 mm Puteaux SA cannon of the wz. 29 car destroyed on 3 September 1939 at Chojnowo. The cannon is partially withdrawn to the inside of a turret, and part of mounting's ring is shot off, but well visible is a design of the ball mounting, and its movability. Note also a shape of bolt heads.

The main armament was a French 37 mm Puteaux SA L/21 low-velocity cannon in the turret, designated in Poland as 37 mm wz. S.A. cannon (often it is inaccurately described in publications as wz. 18 gun, but this was a designation of a heavier tank version). In spite of its WWI-origin, it was a simple, reliable and quite accurate weapon, but its primary purpose was to fight infantry and MG emplacements. These cannons were modified in Poland by adding shoulder butts and telescopic sights wz. 29 (with angled line of sight), offering a good magnification 2.9x and angle of vision 128°[7]. The gun was aimed manually using a shoulder butt. It could fire up 10 rounds per minute. The gun was mounted in Polish-designed standard universal ball mounting. Armour penetration was poor – 12 mm at 0 meters, but it proved enough to fight contemporary light armoured vehicles at close ranges. The range of HE round was up to 2.5 km.

There were 80 round carrieds in a rack on the right side of the car[7,8]. Older publications claimed it was 96 rounds, in 24-round boxes. Per one unit of fire (40 rounds) there were to be 26 anti-tank and 14 HE rounds[7].

Secondary weapons were French 7.92 mm Hotchkiss wz. 25 machine guns in ball mountings of Polish design. An angle of fire was 60° in both axis. One machine gun was placed in left rear side of the turret, at 135° angle to the cannon (it was not possible for the commander to shoot both weapons together). In the pattern vehicle, at the beginning of service, the machine gun and the cannon were swapped, but manning of the machine gun on the left was more convenient. The second machine gun was in rear hull plate, on the left side, manned by the rear gunner. The cars had also the third machine gun mounting in right upper side of the turret (at 135° angle to the cannon and gun and 90° angle to the other machine gun). It was possible to mount the other machine gun in an upper mounting and use it, for example, in street fighting, against upper building floors (it was not effective as an anti-aircraft weapon, as predicted first). A dotation of weapons was two machine guns for the car, so rare photographs with three machine guns must have been for demonstration purpose only. Machine guns had telescopic sights with 1.16x magnification and an angle of vision 40°

The ammunition for machine guns was initially 4032 rounds (according to a description from 1929: 32 96-round belts and 20 lighter 48-round belts). It however evidently concerns original 8 mm Hotchkiss wz. 14 machine gus, while Hotchkiss wz. 25 used 120-round belts. Therefore, a final ammunition supply is not know, but it must have been similar. Probably series cars received from the beginning wz. 25 machine guns, which became a standard in Polish armoured weapons in 1930s.

Armour

The armoured body was made of rolled face-hardened steel plates, of Cr-Ni steel. Armour plates were made by Bismarck (later Batory) Ironworks in Hajduki Wielkie (former Bismarckhütte, currently Chorzów). The armour thickness was from 4 to 10 mm. A thickness and inclination are as follows:

Armour protected against armour-piercing rifle bullets at least from above 300 m, and against ordinary rifle bullets and splinters from all distances.

Construction:

Wz. 29 armored car blueprint
A blueprint of the wz. 29 car (edited, with slight misalignments)
Wz.29 armoured cars
Wz. 29 cars on a parade in Warsaw in June 1937. Well visible is a standard rear stowage, including a railway jack.
Wz.29 armoured car - front Wz.29 armoured car - rear
The pattern vehicle from a front (original shape in 1929) and from a rear (in late 1930s, with platoon commander markings). It differed from series cars by CWS badge, six bolts under a radiator opening not in one line, and wider periscope slots in the turret. Note also a difference in tires (left: Overman, right: Stomil).

The body was on a chassis frame, made of bolted armour plates, connected with angled iron. Access doors were on each side; the door on the left side opened forwards, the door on the right side opened backwards (so the crew could get out under fire from the front or rear). There were five small windows in combat compartment, covered with flapes (two per each side and one on the left in the front plate). Two larger windows, opening upwards and covered with hatches with prismatic periscopes, were located in front of each driver, at the front and rear. Drivers' periscopes had a field of observation 22° vertically and 98° horizontally. Inside, racks for ammunition boxes and a CO2 fire extinguisher were attached to the walls. The floor was not flat, but made of several segments of sheet metal covering frame parts. The crew compartment had a fan in the middle of the floor, in a cylindrical cover, sucking air from under the vehicle and also acting as a step for the commander standing in the turret. The engine compartment was separated from the crew compartment by a bulkhead. On the roof, in front of and behind the turret, there were external angles for stiffening (rather it was not meant to protect the turret ring, being made of a regular steel).

The radiator was covered with an armoured hatch, opening upwards by the driver. In front of the radiator, under the hatch, there was a single road headlight. Below there was a covered hole for a starting crank (the crank was normally transported on the front plate, on the left side of the radiator hatch). Access to the engine was provided by two rectangular flaps on hull nose sides (with the lower front corner cut off to avoid interference with fenders). It is noteworthy, that the height of the engine reached less than half of the side flaps, and higher up under the hood there was an empty space. Tools: a shovel, a pickaxe and a crowbar were fastened outside the car on the left side. On the rear wall there were two tool boxes, a 3-ton jack of railway type and a 7-meter steel towing rope. There was a towing hook between the tool boxes.

The turret was octagonal, with a gun mounting in the front plate and two machine gun mounts in rear side plates. Machine gun mountings were placed at an angle of 135° to the gun and at an angle of 90° to each other. Round holes for the mountings were the same, with a diameter of 269 mm, which allowed for different mounting of weapons. The turret was made of plates fastened with screws on angles, without a frame. There were eight 40 mm wide observation slits in turret walls, and the ninth was in the inclined wall with the upper mounting. Due to the use of prismatic periscopes inside, the slots were protected from a direct fire. Damaged periscopes could have been quickly replaced. A field of observation was 18° vertically and 58° horizontally. As can be seen from photographs, the pattern car differed in much wider slots in walls without gun mountings. Initially, false slots were also painted for camouflage purposes. There was a round observation hatch in the roof, with a two-piece cover, which had a round hole in one part for displaying signal flags. The edge of the cover was bent, creating a gap for ventilation. The turret was mounted on a ball bearing with a diameter of 1070 mm and was rotated manually using two handles. The car had no radio.

The crew consisted of four men: commander-gunner, driver, rear driver and rear gunner. Only drivers had round seats with backrests, on screw bases, which could be adjusted in height and moved forward and backward. Older publications stated that there was a gunner's seat on the front left, but this information is not confirmed in more detailed studies or on the plan. The commander could sit on the cylindrical fan cover under the turret, or he operated weapons in the turret or observed through periscopes standing. He could also sit on a leather belt attached to hooks on the walls of the turret. There are no details known, but evidently the belt could have been fixed in a lower or upper position, when the commander was sitting halfway in the open hatch. Inside the turret there were four hooks for attaching the belt in two positions for operating the gun or the machine gun. According to the original description, the commander could fire weapons while sitting on the belt, but it seems that firing without support on the floor must have been inaccurate, and he could not rotate the turret without support. In the rear part of the compartment to the right of the driver's seat, on the floor there was a seat cushion for the rear gunner, who had a footwell below the chassis frame. Initially, a three-person crew was considered, with one of the drivers acting as a rear gunner.

Chassis: rectangular steel frame made of 6 mm thick C-sections, tapering towards the front. The truck frame was shortened at the rear by 275 mm and an additional crossbar and an auxiliary longitudinal member were added in the rear. The front axle has an I-section profile and was strengthened. A suspension was on semi-elliptical springs: front 940 mm long and 55 mm wide, rear 1500 mm and 75 mm respectively. Tires was initially Overman, semi-pneumatic (or semi-solid) – made of thick rubber with rigid internal elements and air chambers, puncture-resistant. They replaced 895×135 mm truck pneumatic tires and had slightly bigger diameter, but also were 50 kg heavier. As they wore out (according to older publications, since 1934), the tires were replaced with Polish pneumatic Stomil tires 32×6" (812×152mm). At the rear there were twin wheels. No spare wheel was carried.

Ursus-2A engine
Ursus 2A engine with a gearbox of Ursus A truck

Engine: Ursus-2A: petrol, 4-cylinder, 4-stroke, sidevalve, water cooled. A capacity was 2873 ccm[5,7] (or 2722 ccm[1,6], more coherent with cylinder dimensions), cylinder bore/stroke was 85×120 mm. It developed 35 HP at 2000 rpm. Compression ratio was 6.3:1. It was a licensed version of the engine SPA of 1913. A radiator had increased capacity comparing to the truck, and cooling was efficient, even with a closed hatch. The engine had an electric starter Scintilla or auxiliary starting crank.

A fuel tank, under a rear part of the frame, had a capacity of 80 l[7] or 100 l[8] or 115 l[6]. On a front bulkhead in front of the driver there was an auxiliary fuel tank 30 l, or, what's more probable, a vacuum device to supply the fuel[6]. Exhaust pipe was on a left side, before rear wheels.

Transmission: dry multi-disc main clutch. Mechanical gearbox: 4 gears forward, 1 reverse. Rear axle was driven only. A shaft was in a cover. A drixe axle had a double reduction, with a bevel gear and a straight gear. A maximum speed was 40 km/h, but a practical allowable speed was 35 km/h[7]. The average reverse speed was set at 12 km/h – a maximum was 17 km/h, but maintaining it for a longer time caused a risk of engine damage due to high revs. An additional driver's post was at the rear, equipped with basic steering devices, coupled with the front driver's post by means of shafts and rods. Mechanical drum brakes were on rear wheels, an auxiliary handbrake was on the drive shaft.

Electric installation was single-wire 12 V. Cars had a dynamo Scintilla 106 W and a battery Tudor 90 Ah. Electric devices were: a starter, a fan 40 W (Bezet), a headlight (Scintilla), a searchlight with a cable reeler (Curus), a signal, a rear light and interior lighting.



Camouflage:

Wz. 29 cars in August 1934 in Warsaw in the "Japanese-style" camouflage. Note different styles of patches in two platoons.

Initially, armoured cars wz. 29 were camouflaged in an uniform "protective colour", most probably dark olive. Only the prototype in its first version was painted in a four-colour camouflage introduced in 1928 (dark green, dark brown, light yellow-grey and blue-gray, separated by black lines).

This issue has not been covered in publications so far, but the photographs indicate, that in 1933–1934 the cars from Modlin wore non-standard experimental camouflages, most notably a three-colour airbrushed contrasting camouflage (probably of dark brown and light sand or light grey patches upon a dark olive colour – see in a gallery). In winter, a washable white camouflage was applied.

Between 1934 and 1936 the cars were painted in a new standard three-colour camouflage scheme, popularly known in publications as the "Japanese" one. It consisted of contrasting irregular patches, usually described as bright yellowish sand, dark green and dark brown, separated with thin black stripes. Recent publications however indicate, that the colours were: dark yellowish sand, olive green and light blue-gray as the lightest colour (more on a page on tankettes). There was no standard layout of patches.

From March 1936, there was a new final standard three-colour low-contrast camouflage scheme introduced for all Polish armoured vehicles, of irregular patches of greyish sand and dark brown over a base colour of olive green (in fact it was brown-green shade). Patches were airbrushed, with soft transitions, their shapes were mainly horizontal. There was not any standard pattern of patches.

Colour 1939 photo of the wz.29 car [Hugo Jaeger] Unique 1939 photo of the armoured car wz. 29 in a standard late camouflage, captured by the Germans and gathered along with other Polish equipment (probably a training car from Modlin). A cannon mounting in the turret is visible. Note, that colours might be distorted (especially olive green).
(photo: Hugo Jaeger).

An interior should be all greyish sand according to 1938 instruction, but photographs show, that it was painted olive or brown up to window level. According to this instruction, the chassis was olive-green, but chassis parts, fuel tanks, mufflers, exhaust pipes etc. were to be painted black.

The cars wore no nationality insignia at all. In 1939, a usage of any other insignia was forbidden. Only before the war, the cars carried tactical marks for training purposes – they were attached light blue-gray disc (the 1st platoon), triangles (the 2nd platoon) or squares (the 3rd platoon). A vertical brown band meant a platoon commander, and a smaller shape repeated inside – his deputy. Four-digit registration numbers were painted on a front plate around 1931-1933 (on uniform camouflage), then from 1935 until 1936 only. Later, new registration plates, introduced from the beginning of 1937, were carried inside.

Wz.29 car - sideview [Adam Jońca] Wz.29 car - front and rear view [Adam Jońca]
Drawings: Adam Jońca.

Part II: A gallery with additional photos and information on armoured car wz. 29


Specifications:

Crew 4
Own weight approx. 4,000 kg[6]
Combat weight 4,800 kg[5,8]
Length / without MG 5.49 / 5.15 m (216 / 203 in)
Width 1.85 m (72 in)
Height 2.475 m (97.4 in)
Wheelbase 3.5 m (137.8 in)
Ground clearance 35 cm (13.7 in)
Max. road speed 35-40 km/h (22-25 mph)
Road / dirt road range 380 /250 km
Power / weight ratio: 7.3 HP/ton
Wading depth 35 cm
Max. steepness 10°
Fuel consumption 30-36 litres /100 km

Models:

wz.29 in older painting - 1/72 card model, author: Michal Derela
Here's my old 1/72 scratchbuilt paper model of the armoured car wz. 29. Author: Michal Derela.

Models of a wz. 29 armourd car. Links from numbers lead to Scalemates.

1/72 [1/76]:
- Part (A001-72) - excellent Polish high quality model of photoetched brass and resin (1999), out of production.
- Wild Hogs' Models (WH 72001) - Polish resin + metal model (2010), mediocre quality, out of production (a preview)
- F&A Miniatures (FA-72010) – new simple 3D resin kit (2022).
- Military Scales (IDAP Technology) (PMI0009B) – new primitive 3D resin kit, of two parts (too short machine guns, wrong shape of gun mountings, non rotating turret).
- Modell Trans Modellbau (MT72003) - German resin model, average quality, out of production.
- Fine Scale Factory - FSF (WZ06) - old resin model (producer non existing anymore).
- Crusader Models/Ahketon - old metal model, mediocre quality (see it at former Patrick Storto's AFV Museum)
- [20mm] SHQ (PT5) - old lead crude 20 mm wargamer model

1/35:
- GPM (001) - Polish short run from early 1990s, vacuform + metal, long out of production.
- Armo (35016) - Polish high quality resin model.
- F&A Miniatures (FA-35003) – new (2022) simple 3D resin kit. Wrong ehxaust pipe, without an outlet.
- Commander Models (#1-012) - resin model (2013), judging from photos average quality
- Commander Series Models (Nr. 1-06) - resin model, out of production.

Other:
- [1/87] Military Scales (IDAP Technology) (PMI0009A) – simple 3D resin model of two parts (too short machine guns, wrong shape of gun mountings, non rotating turret).
- [1/56] Kromlech (KHWW2005) – new (2019) resin and metal kit.
- [1/48] F&A Miniatures (FA-48018) – new (2022) simple 3D resin kit.

1/25 (cardboard):
- GPM (nr 146 / Kartonowe ABC 15'98) - high quality cardboard model.
- Answer (Kartonowe Hobby nr 11) - high quality cardboard model from 2019.
- Sklej Model (nr 16 (1/2020)) - cardboard model from 2020, late camouflage or winter camouflage.
- Mały Modelarz 5/87 - armoured cars wz.29, wz.28 and wz.34 - old cardboard model, numerous inaccuracies.


Notes:

1. There were not many armoured car types in the world in late 1920s, and part of them originated from World War I. Almost all were built upon commercial 4x2 chassis as well, and some had engines of similar power, but almost all were faster on roads (45-70 km/h). A standard French armoured car, which influenced Ursus design, was AM White TBC from late World War I. With a slightly thinner armour (8 mm), it had the same 37 mm cannon and oppositely mounted Hotchkiss MG. In spite of a greater weight (6 t) and the same engine power (35 HP), it developed maximum speed of 46 km/h. From 1932, these cars were modernized with new Laffly 50 chassis with 50 HP engine. In France there was also developed an unaccepted prototype Panhard 138 with 4x2 drive and two same weapons, faster as well, in spite of a weaker engine. At the same time as Ursus there was produced Berliet VUDB, standing out with its 4x4 drive, but turretless and weakly armoured, meant for a colonial service.

A potential enemy was Soviet BA-27, whose advantage was longer 37 mm cannon (not much better though) placed along a machine gun in turret's front. With only slightly thinner armour (8 mm), it was faster (45 km/h), in spite of the same engine power. It also had rear driver's post, nevertheless its reverse speed was limited to 13.5 km/h as well. However, comparing with 10 wz. 29 cars, there were made as much as 215 of them in 1928-1931. Germany was bound by Versailles Treaty, so they did not produce armoured cars until early 1930s, in spite of creating several heavy off-road armoured car prototypes (4-axle and 5-axle: Daimler-Benz ARW, Magirus ARW and Buessing-NAG ZRW).

A contemporary of the Ursus was British Lanchester (6x4), armed with machine guns, including 0.5 inch heavy machine gun, bigger and heavier, but much faster (72 km/h) thanks to 88 HP engine. Apart from it, there were older Crossley 4x2 cars, armed with ordinary machine guns, mostly produced for export or for colonies. Its variant was Estonian Arsenal Crossley M 27/28, generally similar to the Ursus (and sometimes mistaken for it), armed with a 37 mm cannon or a machine gun only, and with a weaker armour, but much faster (60 km/h). Italy at that time had only World War I armoured cars Lancia 1Z, machine gun armed. Czechoslovakia was one of few countries, which developed a modern armoured car on a special chassis at that time: OA vz. 27 (Škoda PA-III). It was heavier, fitted with a thin armour of a complicated shape, and armed with two machine guns only. As the only contemporary armoured car, it developed similar mediocre speed as Ursus, and its only advantage seemed a stronger engine and a reversing gear. However, due to a complicated construction it costed some $25,000, while the Ursus costed some $10,500 (without weapons). After that, Czechoslovakia designed in 1929-30 an armoured car of a lighter class OA vz.30 (Tatra T-72), 6x4, machine-gun armed. As it shows, at the time of construction the wz. 29 armoured car presented quite modern design, with average capabilities. However, as soon as in early 1930s there started to appear new medium or heavy armoured cars, usually with 6x4 drive and better off-road characteristics, armed with potent anti-tank cannons or automatic cannons, which made older designs obsolete (SdKfz 231, BA-3, BA-6, Landsverk armoured cars, Fiat 611). By the end of 1930s, even better generation of all-wheel drive armoured cars appeared.

2. In July 1939, there were reported 13 armoured cars in the CWBrPanc in Modlin – unfortunately, without a breakdown on types, in which eight of a category B (fit for training and mobilization, with 50% to 90% service life left) and five of a category C (fit for training only, with less than 50% service life left). It apparently made several older authors believe, that 13 wz. 29 cars were produced. In fact, the remaining three cars were wz. 28 or wz. 34 armoured cars – and we suspect, that also the pattern vehicle wz. 29 with a boiler steel armour.

3. According to publications based mainly on the report of Maj. Majewski, only two Ursuses were lost near Seroczyn, one of them north of the village and the other southwest, between Seroczyn and the Świder River. What is unclear is that there are photos of one abandoned Ursus, with a visible sign on the border of the Latowicz commune, approximately 3 km west of Seroczyn. Between Seroczyn and the Latowicz commune there were the villages of Żebraczka (directly across the Świder River), Oleksianka and Strachomin, which at that time belonged to the Iwowe commune, not Latowicz (as currently). The fact that the car in the photos was armed suggests that it was lost in combat rather than abandoned during the retreat.

There are also photos of one car, without a rear wheel, among buildings suggesting a center of the village, described in the German album as Seroczyn, which does not entirely correspond to places of losses (the photograph above in the article). The cars obviously could have been towed by the Germans, but probably over short distances. The uncertainty is further increased by the issue of the photo of a car on a country road, known from numerous photos, regarded as lost in Chojnów, but some German descriptions of the photos suggest that they come from Seroczyn indeed (see in a gallery).


Sources:

  1. Janusz Magnuski: Samochody pancerne Wojska Polskiego 1918-1939; Warsaw: WiS, 1993
  2. A. Jońca, R. Szubański, J. Tarczyński: Wrzesień 1939 - Pojazdy Wojska Polskiego - Barwa i broń; Warsaw: WKŁ, 1990.
  3. Rajmund Szubański: Polska broń pancerna 1939; Warsaw 1989
  4. Witold Jeleń, Rajmund Szubański: Samochód pancerny wz.29, series: Typy Broni i Uzbrojenia nr 84; Warsaw: Wyd. MON, 1983.
  5. Jan Tarczyński, K. Barbarski, A. Jońca, Pojazdy w Wojsku Polskim - Polish Army Vehicles - 1918-1939; Pruszków: Ajaks, 1995.
  6. Rajmund Szubański: Samochód pancerny WZ.29 URSUS; Warsaw: Wydawnictwo ZP, 2013.
  7. Michał Kuchciak: Samochód pancerny wz. 29 w latach 1929-1939, Oświęcim: Napoleon V, 2019
  8. Radosław Mazur: Samochód pancerny wz.29, series: Wielki Leksykon Uzbrojenia - special issue 4/2019, Warsaw: Edipresse Polska 2019
  9. Andrzej Glajzer: Samochody ciężarowe Ursus 1928 – 1930; Warsaw: ZP Grupa, 2007.

Updated:


Main pagePolish armourPolish artillerySteel PanthersContact


All photos and pictures remain the property of their owners, unless they are public domain due to age. They are published in non-commercial educational and research purpose.
Text copyright: Michal Derela © 1998-2024.