The US has fallen behind adversaries in developing long range Air to Aor missiles. While US Air Force had awarded a half-billion-dollar contract to Raytheon for long range air-to-air missile, capable of hitting enemy planes from 100 miles (160 kilometers) away. But China’s latest offering, the PL-15, and another Chinese air-to-air weapon in development, provisionally known as PL-XX, would strike slow-moving airborne warning and control systems, the flying neural centers of US air warfare, from as far away as 300 miles.
The Defense Advanced Research Projects Agency (DARPA) in 2017, published its plan for a rapidly manufactured “Flying Missile Rail” drone that can be launched off the wing of a tactical jet. The idea behind the concept is really two-fold. An FMR is a device that can optionally remain on the wing of a host F-16 or F-18 aircraft and release an AIM-120 missile, or alternately, fly away from the host aircraft acting as a booster and extending the range of an AIM-120, Small Diameter Bomb, or special payload pod.
Deputy defence secretary Robert Work touted the long-considered “loyal wingman” concept at a forum hosted by the Washington Post in Washington DC on 30 March, where he explained that the air force will pair unmanned Lockheed F-16s with F-35s in future battles. “You take an F-16 and make it totally unmanned,” Work says. “The F-16 is a fourth-generation fighter, and pair it with an F-35, a fifth-generation battle network node, and have those two operating together.”
The Air Force Research Laboratory (AFRL), however, is now moving ahead with the development of autonomy algorithms to control pilotless fighter jets. Those algorithms would be hosted in “one or more line-replaceable units” or “brain” that could be transferred between aircraft with minimal effort. “The onboard autonomy must be sufficient for the Loyal Wingman to complete all basic flight operations untethered from a ground station and without full-time direction from the manned lead,” the laboratory explains in a request for information (RFI) notice published in March.
DOD investment in Loyal Wingman technologies comes as the secretive Strategic Capabilities Office pursues an “arsenal plane”. It would carry an array of long-range, precision weapons like cruise missiles, which would be assigned targets from the front lines by the F-35, F-22 and perhaps even the Northrop Grumman B-21 bomber or spy satellites.
Work says the US military will not try to match potential adversaries like Russia and China “soldier-for-soldier” but will instead “offset” their strengths with innovative new weapons. Although many of those proposed devices will be controlled by autonomous computer systems, ultimate authority for the use of lethal force will reside with the human. “We will not delegate lethal authority,” Work says.
A formal programme will be launched in fiscal year 2018 with flight demonstrations running through 2022. These demonstrations will culminate in a capstone proof-of-concept demonstration in 2022, when paired warplanes will conduct a ground strike mission in a hostile, well-defended environment, AFRL says. It did not nominate which fighter platform would be selected for the demonstration.
Extending the range of existing AIM-120 missiles
First off it has to do with creating a low-end “attritable” unmanned system that has a single purpose—to launch an AIM-120 air-to-air missile either while still attached to a host aircraft or by being launched from that host aircraft and flying for 20 minutes along a series of waypoints and launching the missile on command from a remote location. The FMR’s ability to fly for 20 minutes at 690 miles an hour will effectively give U.S. fourth-generation fighters such as the F-16 and F/A-18 another 130 miles to match China’s missiles.
In a combat situation with U.S. and enemy fighters flying towards one another, FMR gives the U.S. pilots a choice. If the enemy is flying better planes with better missiles, the U.S. fighter can launch a FMR and turn tail, staying out of the enemy’s engagement envelope and letting the drone do the fighting. If the enemy is flying inferior fighters, the U.S. fighter can launch the AMRAAMs hanging off FMR’s rails and save the drone for a more dangerous engagement.
US also want to add loitering capability to the FMR. Once the FMR reaches the target area, the FMR vehicle would be capable of loitering until the weapon is released. The first loitering munition, the Israel Aerospace Industries (IAI) Harpy, combined the drone and the anti-radar missile. The Harpy would be launched and enter a searching pattern, waiting for a radar to activate. If a radar activated, the Harpy would then home in on and destroy the radar using a blast fragmentation warhead in its body. The Harpy could loiter over the battlefield for up to six hours after launch.
The United States fielded its own miniature loitering munition in 2012 with the AeroVironment Switchblade. The Switchblade was used by the U.S. Army in Afghanistan to target “high value targets,” whether it be insurgent leaders, mortar teams, or insurgents traveling in a vehicles. While limited in endurance, the Switchblade could loiter over the battlefield if the target was not immediately visible after launch.
The second and maybe the most important aspect of the program is not about what the system can do as much as how it is designed and produced. The goal is to prove that the increasingly damning super long design, testing, and production cycle of modern flying combat systems can be broken. There is a critical DoD need to explore potential new approaches of on-demand manufacturing through the concept of a flying missile rail (FMR). A new advanced monolithic aircraft typically requires 10-25 years to design, develop, and build. New technology concepts are subject to requirements and other processes which can render them programmatically unrealizable before the technology becomes obsolete.
There are two main pieces to this effort: the ability to rapidly build a FMR on demand at a rate of 500 units per month and the FMR itself designed to be produced at a rate of 500 units per month. An innovative approach is needed to ‘build on demand’ and to incrementally enhance existing capability. This would be done by leveraging rapid design, prototyping, and manufacturing processes with an aim of producing 500 of these systems in a single month. Obviously the strategic impact of being able to produce weapon systems or even guided munitions on such an elastic basis would be a huge breakthrough fiscally and logistically, and it would be especially impactful during a time of sustained conflict.
As Flying Missile Rail program manager Lieutenant Colonel Jones says, the concept takes the status quo question of “here’s what I want, how fast can I get it?” and changes it to “here’s how fast I want it, what can I get?” This more agile style of procurement that leverages the latest in manufacturing techniques would allow for far more flexible production and enhanced innovation. In other words, for the dollars spent, the capabilities purchased could be better adapted to the threat faced in the near-term.
However, when the technology is developed it may be applied to other missiles like AIM 260 with ranges expected to be comparable to Chinese PL-15. This will allow US to leap ahead of China both in term of range and also loitering enabled by artificial intelligence. It will also able to match china’s speedier manufacturing capability.
FMR Program structure
The flight performance and flying characteristics of the FMR will be a fallout of the successful performer’s design, and is constrained by the wing hardpoint capacity (to be estimated by the proposer based on public data).
The design and analysis of FMR technology can leverage an appropriate a suite of engineering analysis and modeling and simulation tools in the execution of this task. Additionally, this vision calls for an ability to rapidly manufacture the design in the future. An objective vision would foresee the ability to surge and construct up to 500 FMRs (goal) in a 1 month period.
Design parameters of the FMR may include configuration, payload capacity (1 or 2 AIM-120s, other payloads), aerodynamic design, engine selection, flight performance, minimal payload slot for a radio with a power connector, the radio itself, and an antenna for the radio.
The proposers are expected to choose all elements and components of the design which enable rapid manufacturing and that no equipment will be specified by the government. The FMR must be built for rapid manufacture and be compatible with the F-16 and F-18. Communication equipment (Link-16, weapons data link, etc) can be suggested or provisioned for under the auspices of rapid manufacture of the FMR. Any available low SWAP-C military data links may be considered, assuming that low SWAP-C radios enables rapid manufacture.
Capability creep must not impact the sole mission of the FMR: The mission of the FMR is to be a reusable if not launched from the host platform or fly to a point, loiter, and launch its payload. If the system is launched from an aircraft or if it fires a missile it would not be reusable. If it can hold and fire more than one AIM-120 missile that is a plus, but not a requirement.
Alternate uses for the FMR will be asked WITHOUT a desire to change the design. The FMR does not need to maintain controlled flight after it’s last munition is expended (if designed for multiple munitions) but will have an operational utility if it controlled flight can be maintained. Again, rapid manufacture of the FMR is a priority and any capability beyond flight after launch is a bonus if the rate of 500 per month is not impacted. The AIM-120 is the primary munition to be considered. Any additional munition capability is an added bonus but the AIM-120 is the point of the FMR.
PHASE I: Develop a conceptual design for a flying missile rail and estimate performance. Develop low-risk approaches that are suited for massive surge manufacturing, e.g. capable of rapidly manufacturing up to 500 flying missile rails (goal) in one month. The rail should be capable of acting as a conventional AIM-120 missile rail on F-16 and F-18 aircraft, or optionally acting as an independent robotic range booster for the AIM-120.
Phase I deliverables will include:
- Conceptual flying missile rail design
- The flying missile rail must be compatible with existing F-16 and F-18 loaders. Proposers should source public information to estimate F-16 or F-18 hardpoint capacity. Additional information may be provided during a Phase I.
- Prediction of flight capability and characteristics, suitable for evaluation by a third party.
- Flight time and flight characteristics of the flying FMR with AIM-120 loadout.
- Altitude and airspeed profile of the FMR post AIM-120 launch to end-of-flight.
- Any of the above characteristics by carrying other munitions after the AIM-120 loadout is fully analyzed.
3. Conceptual design of a flying missile rail production approach that produces up to 500 flying missile rails (goal) in one month.
- There is no requirement to manufacture the flying missile rail in austere locations. The objective is on-demand rate and location is part of the analysis.
- Analysis should include transportation of a manufactured device from the manufactured location to and on a C-17 compatible pallet.
- Clearly identified assumptions on rates or pre-requisites
- The Phase II proposal will be due 3 months after Phase I award to promote rapid progress to a Phase II award. For this topic, DARPA will accept proposals for work and cost up to $225,000 for Phase I. The preferred structure is a $175,000, 6-month base period, and a $50,000, 4-month option period. Alternative structures may be accepted if sufficient rationale is provided.
PHASE II: Perform risk reduction on the flying missile rail design and manufacturing approach developed in Phase
- Risk reduction may include:
- Prototype manufacture
- Prototype testing
- Manufacturing approach development or demonstration. The exact content of the Phase II risk reduction approach shall be up to the proposer. It is expected that the choice will be made weighing the greatest technical risks the concept of a flying missile rail and associated manufacturing approach. High impact demonstrations are highly desirable. Approaches and risk reduction activity which lend themselves to follow-on activity (fit testing, captive carry, test flights, manufacturing pilots) are desirable.
For a performer choosing to prioritize flying missile rail design risk reduction, notional Phase II deliverables might include any of the following:
- One or more safe separation mass models representative of the final design.
- Detailed design of the manufacturing approach including cost assumptions required for long term storage.
- Detailed design of a flying missile rail.
- Physical installation of a flying missile rail. Ideally this is suited for captive carry on F-16 or F-18, but DARPA recognizes this level of maturity may not be realizable within scope of Phase II.
- Detailed predictions of flight characteristics and performance.
- Risk reduction demonstration of rapid manufacturing approach.
- Safe separation analysis for the release of:
- The flying missile rail with AIM-120 from an F-16 (stations 3 and 7 with 300 gallon fuel tanks on station 4 and 6) and F-18.
- An AIM-120 from a flying missile rail where the flying missile rail stays attached to the F-16 and F-18.
- An AIM-120 from a flying missile rail (the flying missile rail is flying and the AIM-120 is successfully launched from the flying missile rail). A performer choosing to prioritize manufacturing approach risk reduction could identify alternative deliverables in their Phase II proposal.
PHASE III: The commercial application resulting from this effort will demonstrate to other qualified contractors how to develop rapid and short lifetime systems to the DoD without the traditional long-term programmatic timeline. Learning how to break into the Defense Sector is an extremely powerful and valuable commodity to the commercial sector.
The Military application resulting from this effort will be twofold: an actual on-call mass-manufactured weapon system and a process that can be applied to other systems. This example system, the Flying Missile Rail, is a system which will be utilized immediately but is too low on the DoD priority to procure.
The traditional DoD timelines, operation and maintenance, and life-limit on short term point solutions prevent their procurement. The benefit of an SBIR-enabled “build-on-demand” system demonstrates how to maneuver within the Federal Acquisition Regulations using a different model to achieve rapid capability. This change will address one of DARPA’s challenges. This program is an application of an existing DoD program such as the Air Force Research Lab’s Loyal Wingman Program.