Project of the AAAV / EFV landing vehicle
The EFV (Expeditionary Fighting Vehicle - “Expedition Vehicle”) project was launched in the first half of the eighties under the name AAAV (Advanced Amphibious Assault Vehicle - “Advanced Amphibious Assault Vehicle”). The objective of this project was to create a promising amphibious armored vehicle adapted for the implementation of the so-called. over-horizon landing. The main requirements for the project concerned the level of protection, firepower and high speed of movement through the water. A promising amphibian had to develop high speed on land and on water, and after going ashore to protect the troops and support them with fire.
In the first half of the eighties, the first AAAV project schedule was approved. Until the mid-nineties, it was planned to form the terms of reference for the project, as well as conduct some necessary research. In this case, the first half of the nineties was set aside for the creation of preliminary projects by firms applying for a contract. In the second half of the nineties should choose one of the proposed projects for further development. In the middle of the two thousandth, tests were scheduled, and in the second half of the decades, the AAAV machines were supposed to go into series. It should be noted, due to the mass of serious problems, the work on the project was carried out with significant delays in the schedule at all stages.
The specific requirements associated with high water speeds led to the emergence of several serious design problems. So, for acceleration for the required 40-50 km / h, a suitable hull should have been developed and the car should be equipped with an appropriate power unit capable of driving through water and land. At the same time, the AAAV vehicle was to receive an armored corps with protection not lower than the 4 level according to NATO standards. Thus, there were serious problems with the combination of strength and weight of the structure. Finally, in the course of the work several more basic tasks were formulated, without the solution of which it was impossible to carry out the development of the project.
The variants of perspective armored vehicles for participation in the AAAV project were offered to the company General Dynamics Land Systems (GDLS) and the United Defense Limited Partnership (UDLP). Preliminary drafts of two amphibians were developed already in the late eighties, which made it possible to proceed to experiments on prototypes and prototypes. Until the mid-nineties, project participants collected six prototypes for various purposes, intended primarily to test certain solutions. For example, the HWSTD 1989 prototype of the year with a mass of more than 16 t was equipped with jet propellers, with the help of which it could be accelerated on water to 56 km / h.
In the mid-nineties, after analyzing the submitted projects, the winner of the competition was GDLS. As subcontractors, she recruited several other organizations, including the German MTU engine company. It had to be responsible for the creation of a promising dual-mode engine designed for movement on water and on land.
The AAAV project from General Dynamics was recognized as fully compliant with the requirements of the customer and became the winner of the competition. This project offered several original ideas and solutions that allowed to provide the required characteristics and solution of the assigned combat missions. The original look of the armor hull, non-standard power plant, chassis, etc. were proposed. In addition, the project provided a set of tools designed to improve the hydrodynamic characteristics of the hull.
A promising amphibious amphibious ship was to receive an armored corps capable of withstanding hitting 14,5-mm bullets, as well as providing protection from fragments of artillery shells. At the same time, he had to have the lowest possible weight that did not degrade the characteristics of the machine on the water. The impossibility of using homogeneous armor with the required characteristics made the project authors use a combined protection based on titanium and aluminum alloys, as well as some composites and ceramic materials.
It was reported about the possibility of equipping the car with hinged modules of additional booking, which increase the level of protection. In addition, in 2010, work began on creating a new composite protection, which was planned to be introduced into the new AAAV modifications. The objective of this project was to preserve the required protection while reducing the weight of the structure.
Target practice
The project provided for equipping the machine with additional means of protection. A set of special sensors had to capture the laser radiation of the enemy’s systems, after which it was necessary to use a noise of the appropriate type: a smoke screen, an infrared illuminator, etc.
In terms of the shape of the body, the AAAV should not be different from other similar techniques. The project envisaged a box-shaped hull shape with a frontal part consisting of two main armor plates. At the same time, the car received the bottom of a special profile, designed to optimize the flow around when moving through water.
The layout of the hull was formed taking into account the solution of basic technical problems. The front of the case was allocated for the placement of the transmission compartment, behind which the control compartment was supposed to be located. For the last placed fighting compartment with a tower. In the center of the case was placed a relatively large engine compartment with the main units of the power plant. Aft hull was given under the accommodation of the troop compartment.
Desert trials
In the department of management it was proposed to place the driver (left) and the commander of the landing (right). The vehicle commander and gunner were located in the turret, and the stern compartment contained 16 fighters with weapons. If necessary, instead of landing, it was possible to transport up to 2,5 tons of cargo. The crew of the vehicle and the commander of the landing had their own hatches in the roof of the hull and turret, and the landing had to use a lowered ramp in the rear hull sheet.
To move on the ground or on the water, the AAAV Amphibian had to use a variable power MTU 833 dual-mode engine. When driving on land, the engine used liquid cooling with a radiator and could produce no more than 850 hp. At the same time, torque was transmitted to the front drive wheels using a manual transmission with an automatic transmission. When launched, it was proposed to apply cooling with seawater and transfer the engine power to two jet propulsion with a diameter of 23 inch (584 mm) in the stern. Cooling with outboard water allowed us to develop power up to 2702 hp.
Especially for AAAV, an original chassis has been developed, providing some performance enhancement when driving on water. On each side of the car there were seven rubber-coated road wheels of relatively small diameter with an individual hydropneumatic suspension. When entering the water, it was proposed to raise the rollers to the upper position and pull up the track. In this case, the caterpillar was supposed to rise to the level of the bottom, being placed between it and the side screens.
One of the jobs in the tower
Jet propulsion performed in the form of two blocks in the aft hull. The water was taken through the windows in the bottom, the release through the corresponding windows in the stern sheet. To control the course it was proposed to use partial closure of the output windows. The sides provided opening sash reverse. According to reports, the 2702-strong engine and water cannons allowed to develop a thrust of the order of 10 t.
Studies have shown that acceleration of the armored vehicle to high speeds is possible only in the gliding mode. For this, AAAV has received a set of additional funds. Two sheets with hydraulic drives were installed in the frontal part of the hull. At the stern was located U-shaped design. Falling down, the front sheets were to form a shield of the required size and configuration. The stern shield, in turn, was located in a horizontal position. The lowered shields supplemented the bottom profile and additionally reduced the water resistance, allowing the movement speed to be increased.
In the fighting compartment it was proposed to install a rotary double turret with weapons. The main weapon of armored vehicles identified the automatic gun Mk44 Bushmaster II caliber 30 mm. On the same machine with it was mounted 7,62-mm machine gun M240. The tower was equipped with a weapon stabilizer and a set of various equipment for observing, searching and firing targets. The ammunition consisted of 600 shells for guns and 2400 cartridges for machine guns. On the sides of the tower were smoke grenade launchers.
Landing troops
The relatively high requirements for payload led to the AAAV being quite large and heavy. The length of the vehicle (along the hull) was 9,33 m, when opening the front shield, the longitudinal dimensions increased to 10,67 m. The width of the machine was 3,66 m, height (on the tower roof) - 3,28 m. The combat weight was determined at 36 t.
The estimated maximum speed on the highway was 70 km / h. On the water, the AAAV should accelerate to 45-50 km / h. Fuel tanks with a total capacity of 325 gallons (1230 l) provided a cruising range on the highway over 520 km and up to 120 km on water.
The AAAV project initially developed two major modifications. The main one was the landing vehicle for transporting personnel, known as AAAV (P). In addition, the proposed command and staff modification AAAV (C). It differed from the basic version by other equipment of the landing compartment, in which there were only seven crew seats, and also provided a set of special equipment for receiving, processing and transmitting data, as well as for controlling the troops.
By the end of the nineties, GDLS, chosen by the winner of the competition, was ready to build a new type of experimental machine. It was assumed that in the near future the first prototype will be built, which will soon be released for testing. At this stage, it was decided to change the name of the project. Now, the amphibious assault vehicle was to be called EFV. This name was applied until the very end of the project.
By the middle of the two thousandth, the finished prototype of the AAAV / EFV amphibian passed the necessary ground tests, after which the water tests started. Despite various minor problems and "childhood diseases", the machine as a whole coped with the tasks assigned to it. It was experimentally proved that the EFV can reach the required speed and carry out the landing to the coast during an over-the-horizon landing.
It should be noted, the mass of technical and technological difficulties several times led to noticeable shifts in the timing of the execution of certain works. As a consequence, the original plans were not implemented. In addition, there was a noticeable problem in the form of a constant increase in the cost of the project, which was not yet ready to launch mass production. As of the middle of 2010, the start of the assembly of the installation batch of hundreds of machines was planned for 2012 year. The launch of full-scale production is scheduled for 2015 year. By this time, the project had spent about 15,2 billion dollars.
The complexity and high cost of the project led to the fluctuations of the potential customer and operator, as well as to the adjustment of plans. So, it was originally planned that the installation batch will consist of X-amp amphibians, and a full-fledged order will make 100 units of new technology in two versions. Due to the increasing cost of the project, in connection with which the price of a serial armored car passed through 1013 million, in 22, it was decided to reduce the future order to 2007 machines. In the future, new cuts in plans were not excluded, due to the rising cost of the entire project as a whole and a single machine in particular.
The constant increase in the cost of the project coincided with the plans of the US leadership to reduce the military budget. Having been assigned the task of reducing costs, the Pentagon was forced to wind down a number of promising projects, the further implementation of which was associated with unacceptably high spending. Among other developments, the landing amphibian EFV came under the reduction. At the beginning of 2011, it became known that the draft military budget for the 2012 fiscal year does not envisage any expenditure on the development of a promising armored vehicle for the marines. All work was stopped due to lack of funding and interest from the customer.
Stopping the project also led to the cancellation of plans for the deployment of mass production. From 2012, General Dynamics Land Systems was to build and deliver the first hundred armored vehicles to the customer, and then deliver another 573 unit. For obvious reasons, as a result, the production of EFV machines was limited to only experienced equipment.
The draft airborne combat vehicle AAAV / EFV had a number of positive features, but it was not without flaws. The main advantage was considered a high speed on the water, reaching 45-50 km / h. This made it possible to bring ashore a platoon of marines and continue to support them with fire. To create such a technique, it was necessary to conduct a number of important studies and experimental work, the results of which were used to solve the main design problems.
The main disadvantage of the project was its cost. With the observed increase in the cost of the program, the continuation of work was considered unacceptably expensive. In addition, even before closing, some other claims were made to the project. For example, the profiled bottom of the hull, designed for movement on water in gliding mode, became the reason for criticism. Coping with its main function, it did not correspond to modern views on protection against explosive devices. In addition, the excessive complexity of the project was noted.
EFV project work stopped at 2011. Attempts are being made to use the experience gained in new projects, but the general trends in the field of American armored vehicles do not allow to fully implement it. According to the latest data, some developments on AAAV / EFV can be used in a promising project, which will start in the foreseeable future. According to current plans, at the beginning of the thirties, a promising amphibious amphibian, designated as ACV 2.0, should go into service with the US Marine Corps. During its creation it is supposed to apply the existing experience gained during the EFV project.
The ACV 2.0 project, which may be a further development of AAAV / EFV, starts only a few years later. However, the ILC still needs airborne landing craft. Due to the lack of new amphibious vehicles of this class, it was decided to upgrade the existing fleet of old AAV7A1. Due to the failure of a promising EFV project, outdated technology will have to serve for another two decades.
On the materials of the sites:
http://globalsecurity.org/
http://defense-update.com/
http://armyrecognition.com/
http://otvaga2004.ru/
http://army-technology.com/
http://onr.navy.mil/
- Ryabov Kirill
- Otvaga2004.ru. Wikimedia commons
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