Red Sea Topic Week

By Commander Amila Prasanga, Sri Lankan Navy

A New Threat Looms

The Red Sea, a narrow waterway snaking between Africa and the Arabian Peninsula, serves as a vital route for global trade. Significant energy resources transit the Red Sea, including an estimated 12 percent of total seaborne-traded oil in the first half of 2023, and liquefied natural gas (LNG) shipments that account for about 8 percent of worldwide LNG trade. However, this crucial passage now faces a new and unexpected threat – Unmanned Undersea Vehicles (UUVs) deployed by the Houthi rebels in Yemen.

The Houthis’ use of UUVs marks a significant escalation in the ongoing Red Sea crisis. These submersible drones, while not as sophisticated as military submarines, pose a significant challenge to naval operations designed primarily to counter surface and aerial threats. The emergence of the Houthi UUVs threat necessitates a comprehensive reassessment of the naval defense strategies and tactics being employed in the Red Sea.

How can coalition forces adapt Red Sea operations to enhance undersea defense against unconventional threats such as Houthi UUVs? What steps are required to restore stability in the Red Sea region, emphasizing a decisive response to the Houthi UUVs threat? Furthermore, how must global navies adapt their warfighting techniques to effectively counter the distinct challenges posed by these emerging undersea threats?

By effectively addressing these critical questions, the international community can ensure the safety of vital sea lanes in the Red Sea and establish a framework for countering emerging undersea threats in the future.

Houthi UUV Capabilities and the Evolving Threat

The Houthi rebels in Yemen have injected a new and unsettling element into the Red Sea’s already tense security landscape. In March three undersea telecommunication cables were cut in the Red Sea, which the Houthis have denied doing, but nonetheless suggests a contested undersea domain. While details about Houthi UUVs remain murky, open-source intelligence suggests they are likely commercially-adapted or relatively unsophisticated submersible drones. Despite their presumed lack of sophistication compared to military submarines, these low-cost UUVs pose a significant threat due to several key factors.

The operational range and payload capacity of Houthi UUVs are currently unknown. However, even a modest range, measured in tens of miles, could enable them to target commercial shipping within the Red Sea. Their potential payload could include mines, torpedoes, or explosives packed into the hull, possibly enough to inflict significant damage on unsuspecting commercial vessels.

Houthi UUVs likely lack sophisticated guidance and targeting systems compared to military-grade undersea drones. They may rely on basic GPS or pre-programmed routes, as well as wire guidance. However, this simplicity can also make them difficult to detect and eliminate before they reach their targets.

Traditional naval defenses designed to counter surface and aerial threats are largely ineffective against undersea drones. Sonar technology and undersea surveillance systems are crucial for detecting and tracking UUVs. The preferable escort and maneuver patterns of warships searching for undersea threats may be at odds with the operational patterns that optimize air defense coverage, potentially creating difficult tradeoffs and tensions. This can create a significant challenge for the international coalition forces operating in the Red Sea.

The impact of Houthi UUVs extends far beyond potential damage to individual ships. The very presence of undersea threats is disruptive, given how the stealth of undersea platforms can magnify the effects of their operations and substantially shape the behaviors of those under threat. According to a recent report by the Global Trade Research Institute, even minor disruptions to Red Sea shipping could have a cascading effect on economies in Asia, Africa, and Europe. The specter of undersea threats can stimulate outsized uncertainty and risk, potentially driving up insurance costs and impacting global supply chains further.

Responses and Challenges in a Multi-Domain Environment

Faced with Houthi UUVs lurking beneath the waves, the international coalition in the Red Sea is grappling with a new and demanding challenge. However, the coalition is not without options. There are various strategies and capabilities that can be employed by coalition forces.

Mine Countermeasures warships (MCMs) are crucial for clearing mines potentially deployed by the Houthis, which can be deployed by the UUVs in sea lanes and also deployed near the UUV launch sites. The sonar and mine disposal capabilities of MCM ships can play a vital role in safeguarding sea lanes and improving undersea domain awareness.

Anti-Submarine Warfare (ASW) capabilities can be adapted to the UUV fight, including sonobuoys, towed array sonars, dipping sonars, and deployable hydrophone arrays. These tools can help create a more comprehensive undersea surveillance network in the Red Sea and gather critical intelligence on the telltale signatures of UUVs. An undersea surveillance network can be useful for cueing UUV hunters toward detections, rather than relying hunters to find UUVs using only their organic sensors.

The information-intensive nature of surveilling the complex undersea domain demands thoughtful approaches to intelligence coordination. Information sharing and collaboration among coalition members is critical for locating Houthi UUVs. Real-time data exchange can help predict potential attacks and enable a more coordinated response. Faster reaction times and improved targeting capabilities could potentially be used to intercept Houthi support vessels or launch platforms before they deploy UUVs. Ultimately coalition forces can aspire to strike Houthi UUVs before they are ever deployed by degrading their enabling infrastructure.

Despite the possibility of adaptation, current undersea surveillance capabilities may not be optimal for detecting low-signature Houthi UUVs, particularly in the acoustic environment of the Red Sea. The maritime shipping that continues to transit may transmit significant sound into the undersea environment that complicates UUV hunting, especially as a UUV nears a target merchant vessel. Advanced undersea drones and sensor networks specifically designed for UUV detection are urgently needed. Employing new tactics for UUV detection, engagement, and neutralization will require tailored training and exercises that realistically simulate hostile UUV encounters.

Conclusion

The Red Sea crisis serves as a pivotal moment in the evolution of maritime security. The lessons learned here – the importance of adapting naval power, the dangers of escalation, and the necessity of international cooperation – will reverberate far beyond the shores of this strategically vital waterway. By embracing innovation, fostering collaboration, and developing effective strategies for the undersea battlefield, the international community can ensure the safety and security of global trade routes and navigate the challenges of the 21st-century maritime security landscape.

Forces must consider what adaptations can meet the emerging UUV threat. Investing in cutting-edge drone detection and undersea surveillance systems is crucial for creating a comprehensive UUV defense network. Research and development efforts should focus on advanced sonar technologies and autonomous undersea vehicles (AUVs) specifically designed for UUVs countermeasures. Improved intelligence gathering and information sharing among coalition partners is essential for tracking UUVs and anticipating potential attacks. This includes intelligence cooperation with regional partners and leveraging advanced surveillance technologies.

The Red Sea crisis underscores the importance of international cooperation in addressing emerging maritime threats. Sharing best practices, conducting joint training exercises, and fostering closer collaboration on technology development are all crucial steps towards a more robust response to UUVs. The Houthi UUV threat offers a stark reminder of the need for continuous adaptation and innovation in the realm of naval warfare. Long-theorized unmanned undersea threats have now arrived.

Commander Amila Prasanga, Sri Lankan Navy, is Military Research Officer at the Institute of National Security Studies, the premier Sri Lankan think tank on national security, established and functioning under the Sri Lankan Ministry of Defence. The opinions expressed are his own and are not necessarily reflective of the official views of the institute or the Ministry of Defence.

Featured Image: A Remus 600 UUV being operated by U.S. Navy sailors. (U.S. Navy photo by Capt. Gary Loten-Beckford).

Red Sea Topic Week

By Dr. Bonnie Johnson

The recent crisis in the Red Sea has escalated from Houthi drone and missile attacks on commercial ships to a major Iranian-led, Houthi-supported barrage (300+ aerial threats) against Israel. U.S. Navy and coalition partner warships have intercepted numerous missiles and drones to protect commercial shipping and support Israel’s Iron Dome to successfully defeat Iran’s latest barrage attack. The Navy and coalition are using kinetic weapons – guns and missiles – to intercept the threats.

The Navy and coalition partners have been remarkably successful at thwarting the attacks so far, but at great cost that will be challenging to sustain. According to a recent CRS report, the current events in the Red Sea raise two serious problems: the Navy’s “depth of magazine” that is being taxed, and the highly asymmetric “cost exchange ratio” between the Navy’s expensive missiles and the inexpensive threats they are intercepting. A ship’s “depth of magazine” refers to its limited number of missiles and gun ammunition, which when depleted, requires the ship to be reloaded. This takes considerable time, including travel to a safe reloading area.

The “cost exchange ratio” refers to the large differential between the procurement costs for the Navy’s air defense missiles and the adversary’s relatively inexpensive offensive drones and missiles. The CRS report estimates that the Navy’s air defense missiles range from “several hundred thousand dollars to a few million dollars per missile, depending on the type.” These costs stand in stark contrast to estimates of Houthi Iranian-made drones launched by the dozen that can “cost as little as a few thousand dollars.”

Wes Rumbaugh of CSIS adds the caveat that the cost exchange ratio is an insufficient measure of the real cost and operational considerations of conflicts. He points out the often-underappreciated complexities of defensive missile requirements that must provide precision guidance and exceptional maneuverability, the complex decisions that commanders must make to defend a region, and the value of the defended assets which include lives, expensive ships, and the broader economic impacts of attacks on commercial shipping. He also mentions how the escort mission in the Red Sea requires area defense capabilities that offer better range than point defense capabilities, where attacks often necessitate the use of expensive munitions to protect distant ships on short notice.

There is a high likelihood of wider proliferation and increased use of Red Sea crisis-inspired threats by more terrorist groups and nations over time. The recent attacks have wreaked havoc on regional stability, disrupted shipping, causing terror, escalating the conflict, and potentially normalizing attacks on shipping. The attacking capabilities are relatively easy and inexpensive to acquire and employ. Some fraction of the threats may fail to launch, maneuver, or impact their intended targets, but this can be compensated for by launching many of them simultaneously or over time. Adversaries may realize the asymmetric advantage of depleting warship arsenals and running up expensive price tabs, and purposely use many low-cost, crude threats to gradually reduce defenses through wave attacks. Peer competitor nations may also adopt this strategy and opt for swarms of inexpensive unmanned systems instead of more sophisticated missiles.

Noticeably absent are directed energy (DE) weapons, which multiple senior leaders have called for in response to the Red Sea attacks. The Navy’s SWO boss, Vice Adm. Brendan McLane, has expressed frustration over the lack of DE weapons, including lasers and high-power microwaves to counter the threats in the Red Sea. McLane wants to see industry speed up the development of DE weapons for integration onto warships. The commander of U.S. Central Command, Gen. Michael Kurilla, has also voiced the need for DE weapons, explaining that they are especially needed to counter swarm threats as part of a layered defense. Admiral Chris Grady, Vice Chairman of the Joint Chiefs of Staff, also recently expressed interest in DE weapons to improve the cost exchange of air defense.

Operational DE weapons can help tackle the magazine depth and cost exchange challenges posed by threats. Laser weapons offer the potential for speed-of-light defense against threats with their focused beams – blinding sensors or burning through materials. HPM devices transmit a wider cone of microwave radiation that can damage a threat’s electronics. As with all capabilities, DE systems have their natural limitations and are therefore seen as weapons that could complement existing ship kinetic weapons rather than replace them. Shipboard DE weapons will provide closer range point defense – or self-defense of the ship or surface action group.

To provide area defense, as is needed in the Red Sea crisis, many DE weapons will have to be widely distributed on surface vessels or be integrated onto aerial platforms for coordinated operations. According to James Black of RAND, costs as low as $13 per shot are estimated for some laser weapons—basically the cost of providing power during lasing. Naval Surface Warfare Center Dahlgren estimates similarly low costs per shot for HPMs. DE weapons have unlimited magazines in the sense they are not running out of ammunition. They can be fired repeatedly, limited by a different set of factors like power and cooling cycles, the time it takes to lase or irradiate targets and slew weapons to engage targets, and environmental effects that can lessen the effects of the DE weapons.

DE weapons are coming of age. Studies conducted by the Naval Postgraduate School (NPS) assess the pace of advancement and future warfare implications of technology, including the role of DE in future naval weapons. A team of NPS students developed a historical timeline of progress and milestones of the five different types of DE: lasers, particle beams, electromagnetic pulses, microwaves, and millimeter waves (shown in Figure 1). The color shading indicates the evolution from early-growth and development to current prototyping in four of the five types of DE and current stagnation in particle beam applications. Decades of discoveries and inventions have led to the recent era of rapid development, prototyping, and demonstration of these highly complex systems. Rapid advancements are being made in supporting technologies, such as the power and cooling systems to meet size and weight needs, adaptive optics for atmospheric effects and precision targeting, and integration onto platforms and with combat systems. The rise of unmanned threats, such as those in the Red Sea crisis, is helping push lasers and microwave devices over a final set of operationalization hurdles to deployment. 

A family of DE systems is coming of age across the services. The Navy’s High Energy Laser with Integrated Optical-dazzler and Surveillance (HELIOS) system, designed to interdict drones, is being tested on a destroyer platform and is a “bit beyond” the experimentation phase and primed for growth according to Navy Secretary Carlos Tel Toro. The Navy’s Optical Dazzling Interdictor-Navy (ODIN) system has deployed on eight ships as a softkill system than can blind the sensors of drones. The Marine Corps is developing the LOCUST laser weapon system which will be integrated on tactical vehicles. The Army is developing 300 kW-class laser weapons as part of their Indirect Fire Protection Capability – High Energy Laser (IFPC-HEL) program. Arguably, the Air Force is tackling the most vexing application, integrating DE weapons on aircraft with their Airborne High Energy Laser (AHEL) and Self-protect High Energy Laser Demonstrator (SHiELD) programs. Aerial platforms for DE weapons are key to expanding beyond point defense tactics (self-defense at close ranges) to providing defense for an area, as is needed for protecting the Red Sea region.

HPM devices are maturing at a similar pace. Eric Teger describes the Directed Energy Front-Line Electromagnetic neutralization and Defeat (DEFEND) HPM prototype preparing for near-term field testing by the Navy, Air Force, and OSD. DEFEND is the size of a large CONEX maritime shipping container which could fit onto a ship or be towed by a vehicle. Future advancement will focus on decreasing its size, weight, and power.

Preparing adolescent DE systems for adulthood requires a push to get them across the “Valley of Death” – an often difficult transition from the development to the acquisition community. This is reflected in the possible price tag of $1 billion for the Navy’s first laser weapon program of record. Cost studies are underway to weigh the potential benefits of future low-cost-per-shot with the additional development costs still required to produce the weapons, and the recent unit production cost estimates of $100-200 million for an operational shipboard laser weapon depending on the power level. A challenge to analyzing the overall costs of laser weapons is the absence of previous, long-term programs of record to provide historical data.

In terms of technological advances for crossing the “Valley of Death,” much of what is needed lies in continued testing and evaluation, operationalization, and providing training and education. Efforts are underway for prototyping, demonstrations, range testing, and evaluation of system capabilities and limitations in operational environments. The current DE family of systems are in different stages of maturity, ranging from low Technology Readiness Levels (TRL 3-5) for future systems like the 300kW laser or the airborne laser, to TRL 7-8 for systems like ODIN and HELIOS that are recently demonstrating capability at sea. As systems reach higher TRLs, there remains a significant effort required to transition the systems to ensure they are safe, reliable, usable, and fit to perform as intended in operations. Technological maturity must be complimented by extensive tactical development. More analysis is needed to fully develop DE concepts of employment and how they affect broader tactics and doctrine. These types of analysis can inform additional DE maturation focus areas as identified and described in Table 1.

Table 1 – DE Maturation Focus Areas for Crossing the Valley of Death

Focus areas for DE maturation	Descriptions
SWAP-C (Size, Weight, Power and Cost)	Further reduce the size and weight of DE systems; reduce the amount of power and cooling needed.
Platform integration	Increase and improve the platform integration options for DE systems. Design and tailor host platforms specifically for DE weapon systems; design power, cooling, optics, targeting, etc. to best support DE systems and their associated SWAP-C needs.
Combat system integration	Integrate the command-and-control functions of DE systems with the existing host platform combat systems.
Automated decision aids	Provide artificial intelligence-enabled automated decision tools to support the complex process of operating DE systems
Coordination with kinetic weapons	Fully understand how DE weapons can complement kinetic weapons; develop layered defense engagement strategies for a large variety of likely threat scenarios.
Point defense and area defense	Continue to develop DE weapons for point defense (closer-range self-defense), but also develop concepts of operation for the coordinated use of multiple distributed DE weapons and DE weapons on aerial platforms to provide defensive capabilities for an area.
Engagement doctrine	Develop effective engagement shot doctrine to support coordinated and layered defense use of DE systems in coordination with kinetic weapons.
Safety and deconfliction	Provide DE system deconfliction to ensure the use of DE systems does not inadvertently fire at friendly, civilian, and unintended forces, systems, and platforms. Ensure that laser systems do not blind humans, such as pilots of manned platforms.
DE system sustainment	Plan and prepare to operate and sustain DE systems including maintenance, repair, and logistics.
Training and education	Provide training for warfighters and system operators; provide education to increase and inform the DE community of developers, users, evaluators, engineers, managers, maintainers, and acquisition community.

Conclusion

The recent Red Sea crisis is forcing the Navy to reckon with the rate at which it adopts DE weapons. The crisis has shown that the asymmetric threat is real. The Navy is facing serious challenges with magazine depth and cost exchange ratios as the fleet depletes expensive munitions to counter vastly cheaper threats. The use of cheap drones and missiles is likely to proliferate over time, increasing the potential for the Navy to face numerous low-cost wave attacks alongside more sophisticated threats.

DE weapons offer a potential solution to both the depth of magazine and cost exchange ratio challenges, but only after the technologies cross the “Valley of Death.” A major final growth spurt is required to push the adolescent DE systems into adulthood. The systems must undergo enough operational evaluation to ensure their fitness as safe, reliable, and maintainable capabilities that perform as intended. The DE community and tactical centers of excellence must conduct comprehensive concept of operations and employment analyses to understand how these systems will be effectively used in coordination with kinetic weapon systems. DE systems must be fully integrated with platforms to meet SWAP-C requirements and be operated as part of host combat systems. All of this comes with a sizeable development price tag. The return on investment will be realized as laser weapons and microwave devices come of age and defeat threats with their unlimited magazines and low costs per shot.

Bonnie Johnson is a professor of Systems Engineering at the Naval Postgraduate School. She leads interdisciplinary systems research to explore advanced technologies as engineered solutions for warfighters. She studies the implications of emerging technology on future warfare, specializing in directed energy systems and artificial intelligence.

References

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Demarest, C., Eckstein, M., and Ziezulewicz, “Amid Red Sea clashes, Navy leaders ask: where are our ship lasers?” Navy Times, 22 January 2024. https://www.navytimes.com/news/your-navy/2024/01/22/the-us-navy-could-use-some-lasers-on-its-surface-fleet-right-now/

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Featured Image: November 2014 – The U.S. Navy Afloat Forward Staging Base (Interim) USS Ponce (AFSB(I)-15) conducts an operational demonstration of the Office of Naval Research (ONR)-sponsored Laser Weapon System (LaWS) while deployed to the Arabian Gulf.

Red Sea Topic Week

By COL Jörg Stenzel, German Army, and CDR Michael Posey, U.S. Navy 

Everything in war is very simple, but the simplest thing is difficult. –Carl von Clausewitz

Almost Friendly Fire

In February 2024, a fortunate mishap prevented German Navy air defenders from shooting down an American MQ-9 Reaper in the Red Sea. The frigate misidentified the U.S. drone and fired two Standard Missile 2s at the target – which both subsequently missed. This near-miss incident in the Red Sea and reports about minimal ammunition stocks have triggered many controversial discussions about the German Navy’s capabilities and readiness. These discussions could erode trust—the trust of the German sailors in their professional skills and weapon systems, and the trust of allies and partners. Since trust is the ultimate currency, the impact of this incident demands a closer assessment.

Operations Prosperity Guardian and Aspides: Protecting the Sea Lanes against Houthi Fires

In response to Israel’s Operation Swords of Iron in Gaza, the Houthis, an Iranian-backed rebel group in Yemen, started to attack Israel with drones and missiles. As the Israelis intercepted most attacks, the Houthis changed their strategy. Beginning in November 2023, they attacked commercial ships in the Red Sea, often employing anti-ship missiles, which caused severe damage and forced shipping companies to avoid the Bab el-Mandeb Strait and redirect to a much longer route around Africa. The U.S. formed an international coalition comprising more than 20 nations to protect this critical waterway and launched Operation Prosperity Guardian. In January, the U.S. and Great Britain targeted Houthi positions, and President Biden announced that these strikes were in direct response “to unprecedented Houthi attacks against international maritime vessels in the Red Sea.” On February 19, 2024, the European Union (EU) launched its EU Naval Force (EUNAVFOR) Operation Aspides to protect vessels against ongoing attacks, accompany vessels, and reinforce maritime situational awareness. Unlike its sister mission, Aspides is purely defensive and not authorized to strike in the land domain.

German Defense Minister Boris Pistorius visited the crew of the German Navy warship Hessen in the port of Souda, Creta, shortly before the frigate deployed in their area of operation and said, “The freedom of trade routes and the safety of ships on the most important sea corridor between Europe and Asia are indispensable. […] Germany cannot stand on the sidelines and do nothing.” Protecting the sea lanes has always mattered politically to Germans. For instance, former German President Horst Köhler resigned in 2010 over critiques of his statement that Germany has to be able to secure lines of communication in the global economy.

Fourteen years later, the German Bundestag approved the participation of armed German forces in Operation EUNAVFOR Aspides on February 23, 2024, with 538 out of 573 members of Parliament voting in favor of the mission. Germany’s main contribution to the mission, besides personnel at the Headquarters in Larissa, Greece, and on the flagship, is the guided missile frigate Hessen, seen as its Navy’s “gold standard.”

Modern, Mighty, Mobile: Hessen is State of the Art, yet Misidentified a U.S. Drone

The ship has capabilities in all warfare areas, but its specialty is air defense. The German Ministry of Defense takes pride in the U.S. accepting the ship to provide air coverage for carrier strike group 12 around the USS Gerald R. Ford in 2022. The Hessen has a multifunctional Active Phased Array Radar (APAR) and the long-range air surveillance and detection radar SMART-L to fulfill this role. The latter has a range of 400 km (about 250 miles) and can track up to 1,000 airborne targets at the same time, and the former can detect and track more than 200 targets up to 150 kilometers (about 93 miles). To neutralize airborne threats, the frigate is equipped with one Mk 41 Vertical Launching System for 24 RIM-66 Standard Missiles (SM-2MR) and 32 RIM-162 Evolved Sea Sparrow Missiles (ESSM]), two Mk 49 missile launching systems for RIM-116 Rolling Airframe Missiles (RAM) and an Oto-Melara 76/62 gun. For anti-surface and anti-submarine missions, the ship has a launcher for RGM-84 Harpoon missiles, tubes for EuroTorp MU 90 impact torpedoes, and 27mm autocannon systems. These systems are operated by a command-and-control system with a fully distributed data processing system and a redundant fiberglass data network connecting its sensors and effectors.

On February 26^th, the ship detected an Uncrewed Aerial Vehicle (UAV) approaching the Hessen’s area of responsibility with at least 15 merchant ships sailing within the vicinity. The UAV lacked an Identification, Friend, or Foe (IFF) transponder signal. After coordinating with allied units and the relevant command posts in the maritime area, the commander decided to attack. The two designated SM-2 missiles did not destroy the target, which in this case, was good news as the UAV turned out to be a U.S. MQ-9 Reaper.

While the German Joint Forces Operational Command stated that the technical team of the frigate fixed the issue causing the erroneous SM-2 engagements, the German press reacted with sensationalist stories, with one national magazine headline entitled, “The Navy becomes a laughingstock.” Even after the crew later destroyed two Houthi UAVs, the press speculated about further malfunctions of the SM-2 and ESSM weapons because the ship fired its RAM and cannon to down the two drones. Furthermore, commentators questioned the possibility of resupplying the warship with expensive and limited SM-2 and ESSM missiles.

The Chief of the German Navy took a clear position and defended the crew, calling the actions that nearly ended in the destruction of an allied UAV a “textbook solution,” and making a strong statement that he would have acted in the same way. Still, his statement was vague regarding the ammunition concern, simply announcing that the Navy had enough.

Both the SMART-L and APAR radars detected and tracked the possible air threat, showing their functionality. But the systems are of a technical standard from the late 1990s and may have lapsed into obsolesce. More sophisticated systems can compare the electromagnetic signature of a possible target with a database and could have identified the UAV as a Reaper despite the lack of transponder signal. The Navy knew of this problem, and since 2006, the leadership has tried to close the capability gap. The shrinking defense budget and the costly and prioritized operation in Afghanistan and other stabilization missions have prevented the modernization of these naval systems. Finally, in 2021, the Bundeswehr awarded a contract to Hensoldt to integrate an Israeli long-range radar into the frigate, a complex modernization project that will not be finished before 2027.

The Hessen is not the first high-end air defense platform that misidentified an aircraft. In 1988, while patrolling the Persian Gulf, the USS Vincennes (CG-49) shot down a civilian Iranian Airbus, killing 290 passengers. While the modern-for-its-time cruiser, equipped with the new SPY-1A radar and AEGIS weapons system, patrolled the Persian Gulf during the Iran-Iraq War, the ship’s commanding officer believed his ship was under attack by an Iranian F-14.

The fog of war during the incident could be attributed to a lack of communication on the guard distress channel, crew resource management, technical incongruencies, and mounting U.S.-Iranian tensions in the Strait of Hormuz. Developed to “solve the problem of air defense,” the AEGIS weapons system – so named the “Shield of the Fleet” – was supposed to use automation to reduce human error. Instead, innovative technology has introduced different human errors. The Vincennes incident reminds us that technology can never remove the friction inherent in combat. Further, the Vincennes incident demonstrates that tactical-level mistakes, like aircraft misidentification, can have tragic, strategic-level impacts.

Complex Command and Control Begets Cross-Mission Communication Challenges

The misidentification of the MQ-9 also raises questions about the command and control (C2) design of the operations and the situational awareness in the Red Sea and surrounding waters. Overlapping maritime operations and jurisdictions in the wider area, from the eastern coastal area of Eritrea and Ethiopia to the Strait of Hormuz in the west, could have contributed to Hessen’s lack of situational awareness regarding the MQ-9.

The European Union’s Operation Atlanta has an area of responsibility which includes the Gulf of Aden, the Somali Basin, the Red Sea, the Gulf of Suez, and the Gulf of Aqaba. Operation Agenor, also under the umbrella of the European Common Security and Defense Policy, has responsibilities in an area covering the entire Gulf, the Strait of Hormuz, and a part of the Arabian Sea. Under U.S. Central Command, the U.S. Naval Forces Central Command has established Combined Maritime Forces (CMF) with 41 partner nations. CMF includes five operational staffs, including Combined Task Forces (CTF) with regional or functional responsibilities. CTF 153, which focuses on security in the Red Sea, is leading Operation Prosperity Guardian.

Greek Rear Admiral Vasileios Gryparis leads the EU Red Sea mission from his headquarters ashore in Larissa, Greece, and the Italian Force Commander, Rear Admiral Stefano Costantino, embarks on his flagship Federico Martinengo. This Italian frigate was already in the area, providing maritime situational awareness and escorting the merchant ships. The Caio Dulio guided missile destroyer replaced it on February 8, 2024. It is possible the new commander did not establish comprehensive situational awareness and command and control. Interestingly, the Parliament in Rome formally approved the Italian contribution to the mission on March 5, 2024, days after the nearly avoided blue-on-blue incident with the Hessen.  

Further exacerbating the issue are disparate C2 of sea and air assets controlled by their nation in Madrid, Rome, or Paris. According to the press release, an indicator of the non-existing overall situational awareness is that the Hessen did not coordinate with the Aspides flagship but directly with CTF 153 to request an update on their airspace picture. The response from their headquarters in Manama, Bahrain, led to the conclusion that the detected UAV must be classified as hostile. As later determined, it was a U.S. asset, so either CTF 153 did not have a clear picture of the situation or could not be shared, possibly because of the compartmental classification of this UAV’s particular mission.

Costly SM-2s and Dwindling Weapon Stocks

Usually seconds after firing long-range air defense missiles, Sailors would see the effects of the interception in the sky over the Red Sea and/or on their combat system consoles. However, the crew kept relatively silent since the two SM-2s did not destroy their target. Analyzing the press statement, which informed us that the crew had solved the technical mishap, it is likely that a problem with the fire control system, APAR, existed. The system is optimized to intercept supersonic bombers, like the Russian Tupolev Tu-22M, and ballistic missiles. The Reaper by comparison has a cruising speed of about 170–200 miles per hour and may not have been correctly targeted by the combat system. Furthermore, the drone flew parallel to the vessel, which can intensify the cross-range effect and needs to be addressed by calibrating the settings of the fire control system. It seems paradoxical that a slow airframe would be an advantage, but history proves otherwise. For example, the British torpedo bombers “Swordfish” attacked the battleship Bismarck in 1941 and flew slowly, which caused severe challenges for the ship’s air defense fire control system.

Frequent live fire exercises could have helped detect the problem earlier. Still, minimal stock and costly unit prices from $500,000 to more than a million U.S. dollars per missile led to just a few meticulously prepared launches under near-laboratory conditions over the last 30 years.

The crew engaged two hostile drones the next day, and reading between the lines of the press releases, there are occasional hints that a first attempt to destroy them with an ESSM missile failed as well, most likely for the same reasons as the mishaps with the SM-2. The crew then successfully destroyed the targets with RAM and the vessel’s cannon, which the press criticized again. The commentators argued that nearly any German Navy vessel could accomplish this mission, indirectly questioning the value of the air defense escort of the specialized Hessen, an exaggerated and inaccurate claim. However, the described combat situation shows that the layered defense concept works and the Hessen crew wisely leveraged its lower-cost munitions as the tactical situation permitted.

For good reasons, the German Ministry of Defense keeps information about ammunition stocks secret. The opposition recently used the tool of a Parliamentary Inquiry to learn more, but most of the answers are classified. A spokesperson of the Christian Social Union party, part of the current opposition, stated: “We have now only learned on inquiry that part of the ammunition of the frigate ‘Hessen’ can no longer be procured because there is no longer the corresponding industrial capacity.” Using the SIPRI Arms Transfer Database, the German Navy is on record ordering 108 legacy and six later variant SM-2s. Taking exercises since then into account, the number of available SM-2s should be somewhere between 65 and 80, which would only be enough to arm the Navy’s three air defense frigates with a single loadout.

Finally, crew training and morale matters. As noted above, the leadership supported the crew’s decision. In cooperation with Navy Command experts, the embarked organic technical personnel detected and fixed the problem, showing the utmost importance of trained, experienced, and motivated sailors. Precisely here, the Navy, as the whole Armed Forces, faces challenges in recruiting and retention that can create a severe readiness problem. Highly skilled experts, like technical support or radar operators, are significantly understaffed, leading to long individual embarkment periods and making the profession unattractive.

The Hessen is an excellent example of the high mission rate. On July 24, 2023, the frigate cast off and became, for six months, the flagship of Standing Naval Maritime Group 1, part of NATO’s Very High Readiness Joint Task Force. Released from this duty in January 2024, on February 8 the vessel sailed to the Red Sea and ended its mission there on April 21, making for a total deployment length of almost nine months.

Frequent and long-duration deployments deeply affect morale and ship maintenance. Furthermore, press commentary that appears to broadcast more malicious ridicule than professional criticism could also undermine recruiting.

Hessen’s Near Miss Refreshes Timeless Lessons for the Modern Warfighter

The German military is at a critical inflection point. Changing national security priorities from financial crises, a costly counterinsurgency mission in Afghanistan, and caring for refugees to investment in large-scale combat operations capabilities proves easier said than done. The German military must make every effort to speed its adaptation, especially by mining the combat experience of the Hessen for extensive lessons.

Situational awareness, effective battlespace management, and well-defined command-and-control are indispensable for effective military operation in every domain. Given the importance of operating with allies and partners, information systems must communicate seamlessly in real time. If for any reason information about assets in the area of responsibility cannot be directly shared, workarounds must be created in advance to avoid incidents like the one described.

Warfighters must train as they would fight. All components of sophisticated weapon systems are costly, but their use must be trained under rigorous combat conditions. Even if a common foundation of doctrine and procedure exists, multinational units need time to train together as a team before going into combat operations. Likewise, backup systems and protocols need to be trained regularly. The latest modern technology can never remove the fog and friction for warfighters at sea, as the Hessen and Vincennes incidents demonstrate. Training using backup systems and going back to basics provides a stronger foundation for dealing with ambiguous combat conditions.

Low stocks are a strategic liability. Purchasing weapon systems is certainly expensive, and the desire to reduce costs is always high, but a complex system of systems will not work for long without deep inventories of essential components. This applies to ammunition, maintenance arrangements, and the real-time availability of spare parts.

There are many questions about Hessen‘s mishaps. Even if the German Navy’s participation in the Red Sea is its most dangerous (combat) mission since the Cold War, it may not be remotely comparable to the challenges of large-scale combat operations, demonstrating the importance of learning from this incident. A political declaration of “Zeitenwende” is not necessarily synonymous with ushering in a new era of combat-ready and modern forces. The blue-on-blue near miss in the Red Sea gives evidence for the timeless Clausewitz dictum that everything in war is simple, but the simplest things can be difficult.

COL Jörg Stenzel is a German Army Armor Officer and CDR Michael Posey is a U.S. Naval Flight Officer. Both currently teach in the Department of Military Strategy, Planning, and Operations at the U.S. Army War College in Carlisle, PA. Both authors’ views are presented in a personal capacity and do not necessarily reflect the official views of any government or military service.

Featured Image: German Navy frigate Hessen (Bundeswehr photo)