In 2002, the Swedish army retired light tanks / tank destroyers Ikv 91. This technique, created in the early seventies, no longer met modern requirements, which is why the military decided to abandon it in favor of more modern models. The cars were sent for conservation and museums. In addition, there was a proposal to use decommissioned tanks as the basis for promising samples of special-purpose armored vehicles. Perhaps the most interesting proposal of this kind concerned the creation of an engineering armored demining vehicle.
Recall that a light tank or self-propelled artillery installation Infanterikanonvagn 91 has been developed since the late sixties by the Swedish company Hägglunds & Söner. In 1975, the army received the first production samples of such equipment. The construction of tanks continued until 1978, during which time 212 armored vehicles were manufactured. The tank carried a 90-mm cannon with a high pressure in the bore, designed for firing cumulative and high-explosive shells. Later, the range of ammunition was replenished with a sub-caliber round.
According to the initial ideas of the customer, the Ikv 91 was supposed to be a light and relatively cheap, simple and mobile armored vehicle designed to combat enemy tanks. Through the use of several compromises, the tasks were solved, but the tank actually lost any prospects for further development. As a result, after several decades of operation, the armored vehicle could no longer show the required combat effectiveness and was not of interest to the army. In 2002, the Ikv 91 were decommissioned.
Demining machine at the exhibition of military equipment. Working bodies and jacks are lowered into the firing position. Photo Ointres.se
Even during operation, Swedish light tanks were used in some new projects. In particular, the first prototype of the AMOS self-propelled mortar was built on the basis of the Ikv 91 chassis. The existing chassis could be used in other projects of armored vehicles of one purpose or another. At the beginning of the last decade, simultaneously with the removal of tanks from service, there was a proposal to create a promising specialized vehicle based on a tank chassis.
The characteristic features of the existing chassis, namely the relatively weak booking, did not allow it to be used as part of the front line combat vehicles. Nevertheless, it could solve the assigned tasks at some distance from the front line. In particular, the armored hull of a light tank was considered acceptable for use in the project of a promising demining vehicle.
Unfortunately, the exact name of the project is unknown. In some English-language sources, the promising machine is referred to as the Hurricane ("Hurricane"). This suggests that the project was originally named Orkan in Sweden. At the same time, in most cases, the original development is called more simply: an armored demining vehicle based on the Ikv 91. The design of the new vehicle was carried out by the Swedish company BOA Defense. Probably, the developer of the base tank took a certain part in the creation of the new project.
The overwhelming majority of projects to create new technology based on existing samples use the same approach. The basic machine is deprived of part of the "native" equipment, instead of which certain new units are installed. In the same way, it was proposed to turn the tank into a demining vehicle. First of all, the Ikv 91 was to be deprived of the turret with weapons and all the standard equipment of the fighting compartment. In addition, the side stowage of ammunition was removed from the front of the hull, which led to the release of a certain volume. At the same time, most of the body elements remained unchanged, although some details needed some kind of revision.
The Hurricane demining vehicle, as a whole, retained the existing building. The light tank Ikv 91 had a welded hull, consisting of armor plates with a thickness of 4 to 8 mm. This made it possible to protect the vehicle from small arms when firing from any angle or from 20-mm automatic cannons when attacking from the front hemisphere. After the vehicle mastered a new specialty, the hull was intended to protect the crew and internal units from flying fragments of explosive devices.
The hull of a light tank of the base model had an inclined upper frontal part of a curved shape, which covered both the central part of the hull and the frontal projection of the fenders. In the upper part of the frontal sheet, at the left side, there were some elements of the driver's hatch, as well as a set of viewing devices. As part of the new project, it was proposed to install an additional workplace to the right of the driver's hatch. To install it, a window of the required shape appeared in the frontal sheet and the roof, on top of which an armored unit in the form of a truncated pyramid was to be mounted. The upper surface of the unit received a hatch and viewing devices.
The design of the chassis sides, in general, remained the same. The fenders had vertical sides of a low height, smoothly mated to the roof. At the same time, an additional radiator grill appeared on the starboard side, which is necessary for the correct operation of the new equipment. It was proposed to cover the shoulder strap with a horizontal cover, on top of which an additional casing of special equipment was mounted. Its frontal and stern parts consisted of several tapering sheets, and instead of sides, there were blinds between them. The tank corps' feed was not modified.
The hull layout has been redesigned to reflect the new role of the vehicle. The front part of the hull retained the functions of the control compartment, but now there were two places for the crew. Instead of a fighting compartment, the chassis now had a compartment with target equipment. The feed still contained the engine compartment.
The Infanterikanonvagn 91 tank destroyer was powered by a Volvo Penta TD 120 A diesel engine with 330 hp. To save space in the aft compartment, the engine was placed diagonally at the starboard side of the hull, at an angle of 32 ° to the longitudinal axis of the vehicle. By means of a propeller shaft, the engine was connected to an automatic transmission. That, interacting with other elements of the transmission, provided the rotation of the rear driving wheels.
The undercarriage of the existing structure was not reworked during the Ikv 91 Orkan project. On each side of the hull, six double track rollers with rubber tires were still placed. The rollers had individual torsion bar suspension. In the front part of the hull there were guide wheels of reduced diameter, in the stern - leading ones. Support rollers were not used.
Light tank / ACS Ikv 91. Photo Tanks-encyclopedia.com
An additional power plant was placed on the site of the former fighting compartment, the task of which was to ensure the operation of special equipment. In the center of the hull was an auxiliary diesel engine with its own transmission, connected to the main pump of the hydraulic system. Cooling of the engine and other devices in the central compartment was carried out using radiators in the casing on the roof and on the starboard side. Hydraulic system pipes were connected to the main pump. Pressure was supplied to the working bodies of the machine using several flexible hoses of sufficient strength. The hoses came out of the corresponding window in the right fender niche and connected to the attachments.
The task of combating explosive devices was assigned to a special percussion trawl using an unusual principle of operation. The basis of the trawl was a transverse box-shaped structure suspended from the frontal part of the hull. As follows from the available materials, it was attached to the chassis body using hinges and levers, which allowed it to move relative to the machine within a small sector. On the sides of the box were outrigger hydraulic cylinders, covered with large casings. On the front surface of the box-shaped part there were hinges for the installation of movable working bodies. On the top right, the box had tubes with fittings for connecting to the machine's hydraulics.
The Hurricane demining vehicle received two identical working bodies, placed symmetrically, approximately at the width of the tracks. The working body of the trawl had a main body of small section and high height. Inside the body there was a motor (probably electric) and several moving elements with means of their fastening. At the back, two swinging levers were attached to the body, with the help of which it was connected to the main box of the trawl. The lower arm had attachments for a hydraulic cylinder. The latter, using the principle of a parallelogram mechanism, could lower the working body into a "combat" position or raise it into a transport position. On the two vertical hulls of the trawl and on the frontal sheet of the vehicle, there were several mounts for installing a two-layer rubber screen.
The vertical housings contained the motors responsible for the rotation of the impellers. The task of interacting with neutralized ammunition was assigned to devices like propellers with two rectangular blades made of viscous non-magnetic steel. The drives allowed the impellers to rotate at speeds up to 1200 rpm. The swept disks of the two impellers partially overlapped. The joint work of the two devices made it possible to clear a passage with a width of 3.5 m.
The engineering vehicle was not intended for work on the front line, but still received a weapon for self-defense. On the left hatch of the control compartment, a turret was provided for mounting a rifle caliber machine gun. Also, the crew could have personal weapons, hand grenades, etc. Other weapons on the base tank were missing due to the dismantling of the turret.
A crew of two was supposed to operate the promising model. On the left, in the control compartment, there was a driver, whose workplace corresponded to the control post of the original light tank. To the right, inside his own wheelhouse, was the operator-commander. He could monitor the surrounding area, and also had to manage the operation of mine clearance systems. When attacking the enemy, he was responsible for the use of a machine gun.
For greater convenience of work in various conditions "Uragan" received advanced means of illumination of the working field. A pair of headlights was placed on the main body of the trawl, above the outriggers. Several more lighting devices and reflective devices were located on the bodies of the working bodies. Finally, behind the commander's wheelhouse, in the center of the hull roof, an inclined support was installed with several lanterns for various purposes. Thanks to this equipment, the crew could clearly see the terrain and work without difficulty at any time of the day.
The Hurricane armored demining vehicle with an original design trawl was designed to operate in relatively simple conditions. It was not supposed to be released into the rough terrain of the battlefield, since the trawl was adapted to work on other objects. With the help of "Hurricane" it was proposed to clear dangerous objects of airfields, highways and other flat areas of strategic importance. In this case, the main purpose of the machine turned out to be unexploded submunitions of cluster bombs, air minefields and other explosive devices remaining on the surface.
The Ikv 91 Orkan demining machine could get to the place of work on its own, lifting the working bodies of the trawl to the transport position. Arriving in a given area, the trawl should be prepared for use. The lateral outrigger jacks were lowered to the operating position, in which they were level with the lower track branch. The working bodies of the trawl also went down, after which the impellers were at a height of several centimeters from the ground. The use of lowered jacks made it possible to maintain the correct position of the nose of the chassis and the trawl: the machine could fall back and forth, but the trawl's forward tilt followed by burying the blades into the ground was excluded.
Having brought the impellers to maximum defenses, the crew could start moving through the minefield. Any unexploded ordnance falling under the blade had to be destroyed. The blow with the blade destroyed the mine and threw its debris aside. Calculations showed that this method of demining can destroy and thereby neutralize a dangerous object in just 2 milliseconds, while an electric fuse took about 10 ms to trigger. The fragments of the destroyed product were supposed to fly in different directions. Some of them could fall under the bottom of the hull or under the tracks, others flew forward or sideways. To prevent debris from falling on the roof of the hull, the trawl was equipped with a double rubber screen.
"Hurricane" in the stowed position, the impellers are raised. Photo Strangernn.livejournal.com
Despite the use of unusual ideas and working methods, the original mine clearance machine was of some interest to the Swedish army. At the beginning of the last decade, BOA Defense, by reworking one of the decommissioned tanks, manufactured a prototype Hurricane. According to some reports, this car was tested, confirming the calculated characteristics. Subsequently, it was shown several times to representatives of the military department and demonstrated at exhibitions of weapons and equipment.
Soon after the appearance of the original project, its prospects were announced. It was argued that the Swedish army showed great interest in the new engineering vehicle and intends to order a serial rebuild of the decommissioned tanks. In the near future, four dozen Infanterikanonvagn 91 could go for modernization. Subsequently, an agreement could appear for the modernization of two more batches of 40 cars each. Thus, of the 212 built self-propelled guns Ikv 91, more than half could turn into equipment for the engineering troops.
However, all these plans were soon canceled. For one reason or another, the Swedish army did not want to sign a contract for serial modernization and alteration of existing equipment. The prototype Hurricane was left alone. The tanks removed from service, in turn, were sent not for repairs and restructuring, but for conservation. After the refusal of the military, the project was closed as unnecessary. The further fate of the only experimental vehicle with an unusual trawl is unknown.
Without much difficulty, it is possible to determine at least one of the main reasons for the refusal of the military. In its current form, "Hurricane" looked interesting and promising, but from the point of view of practical application, such a technique had no serious future. The main problem of the project was the specific purpose of the machine. It was intended for the disposal of ammunition on roads, runways and other flat surfaces. Any bump could disrupt the operation of the equipment or even damage its impellers, stopping the process of neutralization. Moreover, an explosion crater could become the most serious obstacle to the operation of the Ikv 91 Orkan. It should also be noted that the vehicle could only destroy the ammunition lying on the surface.
An unusual mine clearance machine was designed to solve a specific task in specific conditions. An attempt to solve the same problem outside the required terrain either would not have yielded results or led to equipment breakdown. The original piece of equipment turned out to be overly specialized. It is unlikely that the Swedish army needed an engineering vehicle capable of working only on the roads and afraid of any irregularities, as well as powerless against buried mines. As a consequence, plans for the future construction of new technology were canceled. An attempt to give the existing tank chassis a new life was unsuccessful. The decommissioned Ikv 91 tanks were sent not for alteration, but for storage.
