Currently, in the interests of the US armed forces, several hypersonic missile systems of different classes are being developed, incl. a number of ground-based systems. One such project, OpFires, is being commissioned and supervised by DARPA. It is expected that a ready-made missile system of this type will be able to expand the combat capabilities of the ground forces – but the army has so far shown only limited interest and has not yet included it in its plans.
At the stage of development
DARPA launched work on the OpFires (Operational Fires) theme in 2017.The goal of the project was to create a hypersonic missile system with a range of more than 500 km. Then it was noted that such a weapon would be able to improve the operational capabilities of the army, but would not contradict the existing agreements. The Agency insisted that hypersonic systems do not belong to cruise or ballistic missiles, and therefore do not fall under the INF Treaty.
A number of commercial organizations have been involved in the OpFires program. Lockheed Martin is the prime contractor responsible for major systems development and component integration. The individual components are sourced from other firms. In particular, Aerojet, Exquadrum and Sierra Nevada Corp. are currently working on the propulsion system on a competitive basis.
To date, within the framework of OpFires, part of the design work has been carried out and tests of individual products are underway. In January, Lockheed Martin signed a new contract with DARPA for a new phase of work. Phase 3 provides for the development of technical requirements for a full-fledged complex with the subsequent development of the project. The value of the contract is $ 31.9 million.
Principles of using OpFires
The finished design of the missile complex will be considered at the end of 2021. By this time, tests of various components will be completed, and the contractor will be able to start assembling an experimental complex. At the end of next year, they are going to conduct separate tests of the rocket stages. Flight tests of a full-fledged product are going to be launched in 2022. The further course of events will depend on the success of the design, the presence or absence of problems and, which is important, on the wishes of the army.
According to the military …
The Pentagon is showing an increased interest in hypersonic weapons and is already planning to adopt them. Together with other projects of this kind, the OpFires program received its support. Funding for hypersonic programs is constantly growing, which is expected to allow ready-made combat-ready models to be adopted over the next few years.
In the early years, the development of OpFires was carried out at DARPA’s own funds, and then funding from the army began. In FY2020 it allocated 19 million dollars for the project. The draft defense budget for the next year proposed to issue another 28 million, but this proposal was not approved. Back in March, long before the budget was adopted, the army decided to abandon its participation in the OpFires project and excluded it from its plans for the development of troops.
However, DARPA and Lockheed Martin remain optimistic and are not going to wind down work. They believe that the OpFires complex should be created with an eye to the distant future. If the army is again interested in the subject of medium-range hypersonic systems, the Agency and contractors will be able to offer a ready-made sample. Accordingly, you don’t have to waste time launching and developing a project from scratch.
Due to various difficulties and limitations, incl. due to the loss of army support, DARPA cannot yet determine the exact timing of the appearance of a ready-made model suitable for adoption. It is already clear that this will happen after 2023, when the Pentagon is going to receive a number of promising weapons. In addition, the Agency indicates completion of the work before the end of the decade.
Tests of different engines with cut-off
The goal of the OpFires program is to create a medium-range mobile ground-based missile system with a hypersonic warhead. To solve such problems, it is proposed to use well-mastered and completely new technologies. Due to the correct choice of solutions, it is planned to ensure an acceptable cost of the complex and ammunition for it, as well as to obtain improved combat characteristics.
The OpFires complex is planned to be built on a PLS five-axle multipurpose chassis. The cockpit of this machine will house all the control equipment, and a launcher will be located on the cargo platform for three transport and launch containers with missiles. Before launch, the rocket will be raised to a vertical position. The wheeled platform is expected to make OpFires a flexible and user-friendly tool for a wide range of applications.
The missile complex will be equipped with the AFATDS tactical control system equipment. This is standard equipment for the US Army’s artillery and missile systems, making it easy and quick to integrate OpFires into existing control loops.
For the complex, a rocket with increased characteristics is being developed using the boost-glide principle. The first stage is responsible for accelerating the rocket to hypersonic speeds and overcoming the dense layers of the atmosphere. Then the second stage will be included in the work, for which a new solid-fuel engine with the ability to change the thrust and shutdown is being developed. This function is positioned as an advanced technology and one of the main novelties of the program. It should provide a significant increase in fighting qualities.
The combat stage is a hypersonic gliding unit without its own propulsion system. Lockheed Martin reports that the combat stage from the AGM-183A ARRW air-launched missile, created according to the TBG project, will be used in this capacity. Such a product has a limited size, which reduces the requirements for the media. According to recently published data, the speed of the hypersonic unit can reach 8M. Non-nuclear combat equipment is assumed.
An ARRW missile drops a hypersonic warhead – this is how the OpFires missile should work
According to DARPA’s plans, the OpFires complex should hit ground targets with known coordinates at ranges of up to 1000 miles (more than 1600 km), which slightly exceeds the lower threshold of medium-range missiles. By changing the thrust and cutoff of the second stage engine, it is proposed to reduce the minimum range, but the exact characteristics of this kind were not disclosed. They will probably be determined only after the completion of the engine development.
Technologies and plans
Until recently, DARPA, Lockheed Martin and other project participants could view the OpFires missile system as a promising weapon that will enter service with the US Army in the future. However, the army has already abandoned direct support for the program and did not include it in its plans for the development of missile forces. As a result, the goal of OpFires was the search and development of technologies for creating hypersonic missile systems – but without plans for direct introduction into the troops.
Some of these tasks have already been successfully solved, which contributes to the completion of the project in the near future. The plans to start flight tests in 2022 look realistic, but the developers are not overly optimistic about the completion date. In addition, the possibility of introducing a new missile system in the troops remains questionable.
As a result, a very interesting situation develops. DARPA and its allies continue to develop the missile system, although it has not been ordered by the army. The army, in turn, supports the hypersonic direction, but finances projects with different features and capabilities. The first of them should go into service as early as 2023.
At the same time, the armed forces may change their opinion about the OpFires project – and in this case, such a complex or its modified version will be brought into service as soon as possible. Otherwise, the result of the current project will be technology and experience suitable for use in future developments. Thus, the OpFires program will in any case give positive results, and only their nature depends on the decisions of the potential customer.