Tucked away in the finer points, the Marines have also suggested this version of the unmanned aircraft could carry AIM-9X Sidewinder short-range, infrared-homing air-to-air missiles to try and shoot down threats on its own. Later portions of the industry day briefing describe this as “desired” future weapons capability, as is integrating the radar-guided AIM-120 Advanced Medium Range Air-to-Air Missile (AMRAAM).

Its onboard data link would also be able to share that information with other platforms to provide them with a better overall picture of the battlefield. Eventually, through the Navy’s plans for an overarching Cooperative Engagement Capability (CEC) network that links all of its ships and aircraft together, the goal is for the drone to be able to cue air-launched air-to-air missiles and ship-based surface-to-air missiles to take-down hostile targets.

A briefing slide that gives a snapshot of the Bataan Amphibious Ready Group's (ARG) activities in August 2017, showing how far flung its components can be just during limited operations. At that time, the ARG included the amphibious assault ship USS Bataan (BAT), the landing platform dock USS Mesa Verde (MVD), and the landing ship dock USS Carter Hall (CTH), as well as the 24th Marine Expeditionary Unit.

As such, the early warning MUX drone would also have a secondary electro-optical and infrared camera suite to monitor and investigate potential surface threats. A signals intelligence and electronic support measures package would give it the additional ability to locate and classify potential enemy threats based on their electromagnetic emissions.

Being able to extend the sensor range of the ARG or ESG and allow its components to operate across a broader area more detached from other surface task forces would be especially valuable for operations in constrained environments , where enemies might quickly appear and disappear, as well as distributed operations across a wider front. Low flying threats in particular, like cruise missiles and drones, can materialize with reduced warning as ship-based sensors are limited by line-of-sight to the horizon. A flying airborne early warning node overcomes this limitation.

In addition to looking out for conventional aircraft, the industry day briefing said the goal was for the system to be able to spot drones as big as what the U.S. military calls Group 3, a category that includes the RQ-7 Shadow and RQ-21 Blackjack , as well as supersonic anti-ship cruise missiles. These are threats that many countries , and even non-state actors , are exploring and which could pose an increasingly serious danger to U.S. amphibious ships and other surface vessels in the future.

In its airborne early warning configuration, the Marines want MUX to be able to be able to loiter autonomously in a designated orbit approximately 100 miles from the deck of an amphibious ship and stay on station for at least 12 hours. The drone's primary sensor would be a radar capable of spotting and tracking aerial threats and an electro-optical sensor coupled with a data link to send that information to the ship in near-real time.

“Think about the ESG, the Amphibious Ready Group, the large-deck amphib: even if it’s up-gunned with a set of [other surface warfare] assets with Aegis radars, we are still missing an airborne early warning capability,” U.S. Marine Corps Brigadier General James Adams, who is in charge of the capabilities development directorate at Marine Corps headquarters in Washington, D.C., said at the industry day, according to USNI News . “And therefore, in the fight of the future, we are going to be tied to the carrier strike group.”

There had been proposals in the past for an airborne early warning version of the V-22 Osprey , which the Marines and U.K.’s Royal Navy considered , but which proved to be too expensive and complex. As such, if a Marine Expeditionary Unit (MEU) embarked on an Amphibious Ready Group (ARG), even as part of a larger Expeditionary Strike Group (ESG), wants this kind of support right now, it has to operate in close coordination with and in relative proximity to a Carrier Strike Group (CSG) or rely on support from the U.S. Air Force or an ally.

But even within Tier one, the early warning requirement is clearly the Marine Corps’ most immediate priority. At present, U.S. Navy surface forces get this support from the E-2 Hawkeye radar planes , which can only fly from the big deck of a full sized carrier or bases on land .

An early "operational view" of the proposed MUX and its mission sets. The Marines now say the drones may not necessarily end up being able to perform all of these roles.

As of June 2018, the mission sets for these aircraft are, in priority order, are airborne early warning, air reconnaissance, electronic warfare, communications relay, offensive air support, scout and aerial escort, and cargo. The Marines say the first four of these are “Tier 1,” meaning they will be a threshold requirement for the final unmanned platform. Offensive air support is in a lower priority “Tier 2” category, while the service explained that other drones might ultimately perform the scout-escort and cargo tasks.

The Marines envision a basic MUX air vehicle with a vertical takeoff and landing capability and the same physical footprint as a UH-1Y Venom helicopter . It would have low-observable features , including a reduced infrared signature , and ballistic protection for key components. The service wants the initial design to have a minimum internal payload capacity of 3,000 pounds, the ability to carry between 3,000 to 9,000 pounds of weapons or other stores externally, a cruising speed between 230 and 345 miles per hour, an unrefueled combat radius of 350 to 700 miles, and the ability to refuel in flight.

Earlier in June 2018, the Marines held an industry day event, which was open in part to members of the press, on the status of the project, which has the painfully long official title of Marine Air Ground Task Force Unmanned Aircraft System Expeditionary – or MUX. The Corps subsequently released additional information from the briefings on the U.S. government’s main contracting website, FedBizOpps .

The U.S. Marine Corps has outlined seven potential mission sets for its proposed future drone, which will be much larger than the service’s existing unmanned aircraft , but will still be able to take-off from and land vertically on the deck of an amphibious assault ship. Though the plans include a wide array of tasks, the top priority is to get the Marine Expeditionary Unit its own airborne early warning capability to help it operate independently of the U.S. Navy’s Carrier Strike Groups in a high-end conflict against a potential near-peer adversary, such as Russia or China .

There is clear potential for the drones to serve as sensor nodes for more offensive strikes, even in this configuration. Using the CEC, the MUX drones could conceivably locate targets and relay that information to other platforms equipped with stand-off anti-ship or land-attack weapons. Even without the direct network connectivity, the unmanned aircraft could still allow elements of an ESG to search a larger area faster for potential threats. And the Marines have already test fired the truck-mounted High Mobility Artillery Rocket System (HIMARS) from the deck of an amphibious ship and have expressed an interest in adding either anti-sip capabilities to that system or the ships themselves. Coupled with MUX, this could give the ARG or ESG as a whole an even greater ability to engage hostile surface targets at sea and on land. The Marines are also considering giving the early warning MUX its own ability to deploy expendable drones, which could extend the range of its own sensor capabilities, and let it act as a distributed relay to feed all of that information back to the ship. The Navy is already working with Northrop Grumman on an experimental unmanned aircraft that fits inside a modified cluster munitions dispenser and the U.S. military has previously explored even smaller types that aircraft can fire from their flare dispensers.

Northrop Grumman A mockup of Northrop Grumman's concept for a small drone inside a modified cluster munitions dispenser.

Brigadier General Adams said that the ability of the MUX to share targeting data with other air and surface platforms through the CEC network might lead the drone to be unarmed in all of its configurations. “So in some respects, it has an unlimited magazine because it’s the cue-er of other people’s weapons, whether it’s an SM-6 (Standard Missile) coming off a ship, or a [Small Diameter Bomb] coming off an F-35 [Joint Strike Fighter] – it can provide [offensive air support] cueing in the networked fight of the future,” he said, according to USNI News. The other Tier 1 MUX types all seem to focus mainly on expanding on one or more of the capabilities in the early warning configuration. The air reconnaissance variant, which the Marines say would never be armed, would replace the air search radar with a wide-area persistent surveillance camera suite and laser imaging system, but keep the other sensors and data link.

USMC Details regarding a notional mission using the MUX in the air reconnaissance configuration.

A standard mission profile could see the drone performing persistent surveillance over one target area up to 350 miles away for four hours before moving on to search a zone up to 400 square miles in size for threats and other objects of interest for another four hours. In the latter case, the unmanned aircraft could be scanning beachheads and landing zones for danger ahead of an amphibious assault or scouring planned overland routes for ambushes. The electronic warfare version would have a much more powerful electronic support and electronic attack system and a wide-area search radar, which could potentially include a ground moving target indicator functionality to monitor hostile movements, along with the electro-optical and infrared cameras. A key mission for this variant would be jamming enemy integrated air defenses in order to better allow F-35B Joint Strike Fighters to neutralize them. It could also help supply targeting information directly to those aircraft or elements of the ESG offshore and do so at least semi-autonomously.

USMC A possible electronic warfare mission profile for the MUX.

There's no reason why MUX couldn't provide valuable electronic warfare support to the more vulnerable elements of a Marine Expeditionary Unit's air combat element, such as the Ospreys or its various helicopters. And in the same way that the drones make up for amphibious ships being unable to host the E-2 Hawkeye, this configuration helps makes up for the gap left by the Marine Corps' decision not to buy the EA-18G Growler. Those aircraft would not be able to operate from the deck of an amphibious assault ship anyways. The Marines also say that Hellfire missiles and the aforementioned expandable drone capability will be threshold requirements for this type. The idea is that this would allow it to perform precision strikes against high value, time-sensitive targets by itself. One scenario the industry day briefing specifically describes is striking at militants or terrorists attempting to flee a site in a vehicle traveling at 80 miles per hour. And despite its description as a communications relay, the Marines seem to envision the last Tier type as a much more multi-purpose configuration with virtually the same systems as the air reconnaissance type and the ability to launch Hellfire missiles. Firing smaller and more cost-effective Advanced Precision Kill Weapon System II (APKWS II) laser-guided rockets is also a “desired” capability for this type.

USMC A concept of operations for the MUX operating in the communications relay role.

Still, the primary goal for drones acting in this role would be to fly in a wide orbit for up to 48 hours at a time while sharing video, signals intelligence, and other data back and forth between different platforms, potentially across different waveforms. It’s not clear in this case whether a single MUX aircraft would be airborne for this entire two-day period or if the full system would perform this role, with multiple drones taking shorter shifts. With a mid-air refueling capability, a single relay aircraft could potentially stay aloft indefinitely. The Tier 2 offensive air support MUX type actually sounds very similar to this version even though it is clearly expected to be more of an actual unmanned combat air vehicle (UCAV) configuration. The main difference would be the mission profile, where it would work directly with MV-22s carrying Marines ashore, sharing information with those aircraft en route, and then loitering over the battlefield for the next six to eight hours providing close air support. There is the possibility the Marines could add the ability to employ Small Diameter Bombs to this variant.

USMC A notional mission plan for the Tier 2 MUX.

The commonality between the types is entirely by design. The Marines make it clear they’re looking for plug-and-play sensors they can rapidly swap out in the field to get MUX drones back in the air performing different missions relatively quickly. The goal is also for the unmanned aircraft’s onboard mission computers and the ship-based control equipment to readily allow for updates and improvements and have at least some features in common with other existing and planned unmanned aircraft, including the RQ-21 and the MQ-25 Stingray carrier-launched drone. Where things get more complicated is in the third tier, which includes missions the Marines suggest might require a larger or different platform from the one they have in mind for the initial MUX types. Separately, in cooperation with the U.S. Navy, the service is experimenting with modified, unmanned UH-1 Huey helicopter that can fly autonomous resupply missions. The Corps has also been looking into other, much smaller unmanned systems for logistical purposes. And the Marines had originally envisioned the escort variant as something potentially as large as a pilotless Osprey and might even land and take-off like a conventional aircraft. This type could carry a much more substantial payload out to much greater ranges.

USMC The MUX may not even up fulfilling this notional Tier 3 scout mission.

USMC The same goes for the cargo-carrying role.