Russo-Ukrainian War: The Zlin Z-137T Agro-Turbo

Source: Reddit

     Anyone that monitors news feeds and social media images and videos of the Russo-Ukrainian War will often notice that much of the land in which engagements happen is on flat and open fields punctuated by thin lines of trees. There is good reason for that and why Ukraine is called the “Breadbasket of Europe”; some 71% of Ukraine's entire land mass is agricultural and Ukraine is one of the top three exporters of grain such as wheat. As such, it should not be surprising that crop dusting aircraft would be in use to service farmers and their fields. Except, in this instance, insects are not the targets but instead, Russian drones are. Some bloggers have nicknamed the aircraft shown here “Stuka” after the Junkers Ju 87 dive bomber of World War Two fame (or infamy depending on one's outlook). While there is a very superficial Ju 87 resemblance based on the aircraft's angle in this smartphone video screen capture, the aircraft is in actuality a Zlin Z-137T Agro-Turbo agricultural aircraft.

     Built by the Czech company Zlin Aircraft Otrokovice (formally Moravan Otrokovice), the Z-137T is derived from the earlier Zlin Z-37 Čmelák (“Bumblebee”). The prototype first flew in 1981 with production commencing in 1998 and when manufacturing ceased in 2007, a total of 56 aircraft were built (of which five were prototypes). A factory fresh Z-137T in 1998 carried a price tag of $230,000USD fully equipped for agricultural duty.

     The Z-137T is a single-seat aircraft with maximum agricultural work take-off weight of 5,566 pounds. Length is 34.3 feet, height of 11.5 feet, a wingspan of 44.7 feet, and a wing area of 256 square feet. Power comes from a Motorlet Walter M601Z reverse-flow, axial-centrifugal turboprop engine which develops 490 shaft horsepower. The engine drives a three-bladed, constant-speed propeller built by Avia. At an altitude of 500 meters, the maximum cruise speed is 157 miles per hour while the absolute maximum speed of the Z-137T is 177 miles per hour. Climb rate is 827 feet per minute. The service ceiling is 18,054 feet and with 92.5 gallons of onboard fuel, the maximum range is 216 miles. The Z-137T needs 1,905 feet of runway for take-off and 2,365 feet for landing.

     The Z-137T has a auxiliary 30 kilowatt drive system which operates the agricultural attachments such as chemical spraying gear or a rotary duster for dry fertilizers or pesticides. The former has a spray swath width of 131 feet while the duster has a 98 foot spread width.

     Of course, this modified Z-137T has replaced any agricultural apparatus for missile pylons. The Z-137T does have four hardpoints, two per wing, which are normally used for external fuel tanks to increase the aircraft's range. Here, the two inner hardpoints are fitted with fuel tanks (which, as a note, cannot be released by the pilot) while on each outer hardpoint is a single Vympel R-73 (NATO reporting name AA-11 Archer) short-range, infrared homing air-to-air missile (AAM). As Ukraine has a sizable stockpile of R-73 missiles, many of them have been repurposed for use as surface-to-air missiles (SAMs) and, as indicated here, allocated to drone-hunting aircraft. The Z-137T, because of its speed, is well suited to drone interdiction in comparison to jet fighters. The typical Geran-2 drone has a maximum speed of 115 miles per hour and so the Z-137T can catch up to them even at cruise speed. It can also launch the R-73 towards the drone without the worry of overtaking the target and risking getting caught in any detonation of the drone's warhead. This is very much a risk for much faster moving jet fighters. Also, the slower close rate of the Z-137T against a drone means a longer time for the pilot to line up the target and achieve the best chance for a missile lock. Finally, aircraft such as the Z-137T are optimized for low altitude flight and can better operate at lower altitudes. The R-73, when used by fighter aircraft, is tied into the pilot's helmet-mounted sight. With but a glance to the target, the information is sent to the missile prior to launch. It is not known if the Z-137T's pilot has a HMS or if targeting is dependent on getting close enough to the targeted drone for the R-73's seeker to pick up the heat signature. The R-73 has a top speed of Mach 2.5 thanks to its solid-fuel rocket engine and it can carry its 16 pound warhead out to a range of 19 miles.

Avia B.534: Pre-War Fighter Excellence

Source: Author's collection

     The Avia B.534 is considered by some to be the most important Czechoslovakian aircraft built during the 1930s and was certainly the most well known to many nations of the time. It was also the most prolific in terms of production numbers with 566 of all B.534 types being constructed. The man behind the B.534 was František Novotný and throughout 1932, he designed the B.34/2 with the first prototype taking to the air on May 25, 1933. The aircraft, now designated the B.534-I, was turned over for testing and on September 10, 1933, the public got to see the new fighter at an exhibition. The second prototype was completed in late September 1933 and featured a fully enclosed cockpit. Extensive testing was carried out through the first half of 1934 with April 14, 1934 standing out when test pilot Václav Kočí flew the second prototype to a Czech national speed record of 227.2mph. The Czech Air Force (Vzdušné Síly) finally put in an order for the B.534 on July 14, 1934 with an initial purchase of 34 aircraft with first deliveries occurring in October 1935. The most numerous version in service was the B.534-IV, with 253 being built, and that is the aircraft shown here.

     The B.534-IV was powered by a Hispano-Suiza HS 12Ydrs 12-cylinder, liquid-cooled V engine developing 850 horsepower which gave the aircraft a top speed of 245mph at 14,435 feet and a climb rate of 2,953 feet per minute. The B.534-IV had a wingspan of 30.1 feet, a length of 26.1 feet, height of 10.2 feet, and a wing area of 253.61 square feet. Armament consisted of four 7.92x57mm Kulomet vz. 30 machine-guns fitted in the forward fuselage with 250 to 300 rounds of ammunition per gun. If need be, six 22 pound bombs or four 44 pound bombs can be carried on underwing racks. The loaded weight of the B.534-IV was 4,674 pounds and with full tanks, the fighter had a range of 360 miles. At the time the B.354-IV entered service, it was superior to many of the fighters fielded by the British, U.S., and the Soviet Union. In fact, even in 1937, the B.534 stood up well against many fighters, only being truly bested by the Messerschmitt Bf 109B.

     The aircraft in the photograph belonged to the Slovak Air Force (Slovenské Vzdušné Zbrane) which came into existence when the Slovak State (Slovenský Štát) began on March 14, 1939 following its declaration of independence from Czechoslovakia. A client state of Germany, Slovak forces participated in the German invasion of Poland, the only other Axis country to do so. Slovak units under Field Army Bernolák (Slovenská Poľná Armádna Skupina "Bernolák") fought in Poland from September 1 through September 16, 1939, subordinated to the German 14. Armee under Heeresgruppe Süd (Army Group South). The Slovaks were victorious in seizing territory in a disputed region along the Poland-Slovakia border. Later, in 1941, the Slovak Expeditionary Army Group and later the Pilfousek Brigade fought in Russia, being attached to the German 17. Armee. However, the Slovak forces lacked command structure, had logistical problems, and were short on motorized transports and despite seeing some frontline combat, were usually relegated to rear-area security operations. Involved in the Russian campaign were three Slovak Air Force squadrons. The B.534-IV aircraft used by the Slovak Air Force had been former Czech Air Force planes but by mid-1942, the fighter was long eclipsed by superior designs and was removed from front-line service and distributed to training units.

     The B.534-IV seen here has a German Balkenkreuz painted on the fuselage, no doubt to aid in identification and prevent friendly fire incidents. The emblem on the tail rudder was that of the Slovak Air Force and consisted of a double cross on a field within a circle. In this case, the cross is blue on a red field within a white circle. Some aircraft had a red cross on a blue field. This emblem was repeated on the top of the wings and on the bottom of the lower wings. In addition, some B.534-IV aircraft added the German Balkenkreuz beside the Slovak emblems. Later, Slovak Air Force aircraft used their own version of the Balkenkreuz that consisted of a blue cross with white borders with a red circle in the center. The overall color was a dark green with whitish-gray undersides.

     The Slovak Air Force ceased to be when the Slovak State came to an end on April 4, 1945 when Slovakia fell to the Russians during the Bratislava–Brno Offensive and both Slovakia and Moravia were returned to Czechoslovakia. Other users of the B.534-IV during the war was Bulgaria which operated some 48 to 78 aircraft (which they called the “Dogan“, or Hunting Hawk), Germany (mostly as training aircraft and glider tugs), and Romania (which used several as glider tugs). 

     Today, no complete B.534 exists in the world. A replica B.534-IV is on display at the Prague Aviation Museum in Kbely, Czechoslovakia while another replica, a cannon-armed Bk.534 variant, is on display at the Slovak Technical Museum at Košice International Airport, Slovakia. Both replicas incorporate some original parts but the majority of the components had to be fabricated. There is also a airworthy replica, though not to scale (it is 30% smaller than the actual B.534) that was built by Stanislav Fiala starting in 2002. The first flight took place in 2009 but following testing, needed modifications which made Ultralight certification difficult. It was not until October 2012 was the replica certified and it carries the code OK-QAB-1. Power comes from a Walter Mikron III engine with the frame being chrome-molybdenum tubing with wooden wings and tail surfaces. The plane is painted in the colors of the 1. Letecky Pluk (1st. Air Regiment), either the 32. Letka or 34. Letka (32nd. or 34th. Squadron), of the Czech Air Force.

Russo-Ukrainian War: DITA 155mm SPH

Source: Public Affairs, 12th. Special Operations Brigade

     The Netherlands has provided Ukraine with nine DITA 155mm self-propelled howitzers (SPHs) and this is one of them, in service with the Artillery Group, 12th. Special Operations Brigade “Azov”. The DITA (Digital Integrated Targeting Artillery), built by the Czech arms manufacturer Excalibur Army, entered production status in 2023 and it shares a high level of commonality with another Excalibur Army product, the DANA M2 152mm SPH. The key difference is the caliber of the howitzer. The DANA M2 uses a 152.4mm howitzer, a caliber that is mainly unique to artillery from the former Soviet Union, from former Warsaw Pact countries, and currently from the Russian Federation. The DITA, on the other hand, uses a 155mm howitzer which is the standard caliber across most NATO countries and thus is capable of firing any compatible 155mm projectile regardless of the country of manufacture. Both calibers still find widespread use in military forces around the world, to include Ukraine which fields self-propelled guns and towed artillery using both 152mm and 155mm calibers, the latter typically coming via military aid from NATO countries. In addition to the nine, the Netherlands has pledged to provide another six DITA. 

     The 29-ton DITA uses a Tatra 815 VP31M 8x8 wheeled truck chassis which uses a Tatra T3C-928-90 12-cylinder, air-cooled, turbocharged vee diesel engine that develops 408 horsepower that is mated to a Tatra Norgren 10-TS-210N semi-automatic transmission. The gearbox has 12 speeds: 10 forward, 2 reverse. This provides the DITA with a top road speed of 55 miles per hour and in optimum off-road conditions, the maximum speed is 15 miles per hour. Off-road performance is improved through a central tire inflation system (CTIS). Enough diesel fuel is carried to give the DITA a maximum cruise range of 372 miles.

     The main weapon is a 155mm L45 howitzer situated within a centrally mounted turret. The mount permits a maximum howitzer elevation of 70 degrees and 3 degrees of depression. The turret does not provide a full 360 degrees of traverse, offering only a total of 60 degrees of total traverse. The DITA has outriggers to stabilize the vehicle when firing from the halt with hydraulics that can quickly deploy and retract to enable the DITA to be ready for firing fast and move just as fast once the fire mission is complete. The DITA uses much the same electronics from the Czech company Retia that equips the DANA M2. In regards to the howitzer, the ASAP (Automatic Setting of Action Position) system permits the DITA to fully automate firing data calculations which in turn directs the turret to traverse and the gun mount to lay the howitzer at the optimum elevation to engage the target. The ASAP system also selects the appropriate ammunition from the 40 rounds carried in the DITA's 40-round automatic loader. Both the commander and the gunner are provided with a digital fire control system (FCS) that tie into the ASAP system. The DITA can be manually aimed using a ZZ-73 mechanical sight, a PG-1M-D panoramic telescope, a K-1 collimator, and a PAB-2A artillery compass. These are calibrated for the 155mm caliber. For manual direct fire, the gunner would use a OP-5-38D telescopic sight. With the automatic loader, the DITA can fire up to 6 rounds in the first minute with a sustained rate of 5 rounds per minute. It is known that some of the DITAs in Ukrainian service are firing the U.S. made M107 155mm HE (High-Explosive) projectile. The M107,which remains in production despite being introduced in 1959, has a weight of 95 pounds with a M739 fuze of which 14.6 pounds is Composite B explosive. Upon detonating, the M107 can produce almost 2,000 fragments. With a full powder charge, the M107 has a maximum range of 12 miles and if using a base bleed M107 variant, the range can be extended out to 20 miles. Of course, the 155mm L45 howitzer can fire RAP (Rocket Assisted Projectile) shells which can reach a maximum range of 24 miles. Unlike the DANA M2, the DITA is not fitted with a heavy machine-gun for anti-air or local defense. Instead, the DITA has to rely on any small arms carried by the crew.

     For armor, the cab is protected to STANAG 4569 Level 1 standard. This is proof up to 5.56x45mm and 7.62x51mm ball ammunition at 30 meters and against 155mm artillery shell fragments at 100 meters. Against explosives, the armor can protect against hand grenades and small artillery fragmentation submunitions. The turret is not armored as the howitzer can be operated from within the cab. The cab is also NBC (Nuclear Biological Chemical) protected and crew comfort provided by a heater and air-conditioning system. Speaking of crew, the DITA can be operated with as few as two men though three is the usual compliment.

     Other systems mounted on the DITA include 24 volt water-cooled auxiliary power unit (APU) paired to hydraulic pump which permits the vehicle's electrical systems to work and the pump allows the gun controls to function if the engine is turned off or broken down. If even the APU fails, the howitzer has manual controls which can be used to aim, load, and fire the howitzer. The driver is provided with a Retia digital diagnostics system to monitor critical systems as well as a video system to enhance situational awareness while driving. A Retia digital communications suite includes a C2I (Command, Control & Intelligence) function, VHF/UHF tactical radio station, and a intercom system for the crew. A Retia inertial navigation system is backed up by a GPS (Global Positioning System) and this is also tied into the ASAP system.

Russo-Ukrainian War: DANA M2 152mm SPG

Source: Ministry of Defence of Ukraine

     Belonging to one of the two self-propelled artillery battalions of the Artillery Group, 56th. Motorized Brigade “Mariupol” is this DANA M2 152mm self-propelled howitzer. Standing for Dělo Automobilní Nabíjené Automaticky (literally “gun on truck loaded automatically”), the DANA M2 is a Czech modernization of the Samohybná Kanónová Húfnica vzor 77 DANA (ShKH vz. 77 DANA; Self-propelled Howitzer Model 77) which entered service in 1981. The modernization is done by the Czech arms company Excalibur Army. Ukraine had purchased 30 DANA M2 vehicles and as of February 12, 2025, none have been lost in combat.

     The 30-ton DANA M2 uses a newer Tatra 815 8x8 wheeled truck chassis which uses the more powerful Tatra T3-930-52M 12-cylinder, air-cooled vee diesel engine that develops 355 horsepower that is mated to a Tatra Norgren semi-automatic transmission. This provides the DANA M2 with a top road speed of 55 miles per hour and in optimum off-road conditions, the maximum speed is 15 miles per hour. Off-road performance is improved through a central tire inflation system (CTIS). Enough diesel fuel is carried to give the DANA M2 a maximum cruise range of 372 miles.

     The main weapon is a 152.4mm howitzer situated within a centrally mounted turret. The mount permits a maximum howitzer elevation of 70 degrees and 4 degrees of depression. The turret does not provide a full 360 degrees of traverse, offering a maximum of 225 degrees of total traverse. Traverse is lesser if the howitzer is at full elevation, being limited to 45 degrees of total traverse. The DANA M2 has outriggers to stabilize the vehicle when firing from the halt with hydraulics that can quickly deploy and retract to enable the DANA M2 to be ready for firing fast and move just as fast once the fire mission is complete. Excalibur Army was not stingy in equipping the DANA M2 with electronics from the Czech company Retia. In regards to the howitzer, the ASAP (Automatic Setting of Action Position) system permits the DANA M2 to fully automate firing data calculations which in turn directs the turret to traverse and the gun mount to lay the howitzer at the optimum elevation to engage the target. The ASAP system also selects the appropriate ammunition from the 36 rounds carried in the DANA M2's 36-round automatic loader. A further 4 rounds plus charges are stored in the turret. Both the commander and the gunner are provided with a digital fire control system (FCS) that tie into the ASAP system. The DANA M2 can be manually aimed using a ZZ-73 mechanical sight, a PG-1M-D panoramic telescope, a K-1 collimator, and a PAB-2A artillery compass. For manual direct fire, the gunner would use a OP-5-38D telescopic sight. With the automatic loader, the DANA M2 can fire up to 5 rounds in the first minute with a sustained rate of 4 rounds per minute. Ukraine does utilize Czech ammunition and so the usual munitions are the 152-EOF HE (High-Explosive), DN1CZ HE-ER (High-Explosive Extended Range), and the 152-EPrSv HEAT (High-Explosive Anti-Tank) shells. The HE shell has a maximum range of 11 miles while the DN1CZ shell can attain a range of 16 miles. For direct fire using the HEAT round, the typical effective range is 1.2 miles. The DANA M2 is fitted with a 12.7mm NSVT heavy machine-gun for anti-air and local defense in addition to any small arms the crew may have.

     For armor, the cab is protected to STANAG 4569 Level 1 standard. This is proof up to 5.56x45mm and 7.62x51mm ball ammunition at 30 meters and against 155mm artillery shell fragments at 100 meters. Against explosives, the armor can protect against hand grenades and small artillery fragmentation submunitions. The turret is not armored as the howitzer can be operated from within the cab. The cab is also NBC (Nuclear Biological Chemical) protected and crew comfort provided by a heater and air-conditioning system. Speaking of crew, the DANA M2 can be operated with as few as two men though three is the usual compliment with room in the cab for 1 to 2 passengers.

     Other systems mounted on the DANA M2 include 24 volt auxiliary power unit (APU) paired to hydraulic pump which permits the vehicle's electrical systems to work and the pump allows the gun controls to function if the engine is turned off or broken down. The driver is provided with a Retia digital diagnostics system to monitor critical systems as well as a video system to enhance situational awareness while driving. A Retia digital communications suite includes a C2I (Command, Control & Intelligence) function, VHF/UHF tactical radio station, and a intercom system for the crew. A Retia inertial navigation system is backed up by a GPS (Global Positioning System) and this is also tied into the ASAP system.