Team HydraStrike
Team HydraStrike
Stanford University
Modern Threats, Modern Solutions: How Team HydraStrike is Reinventing the Mark 48 Torpedo
The Team
Andrew Couillard
Andrew is a first-year MBA student at Stanford GSB who passionate about building frontier tech that strengthens U.S. and Allied capabilities. As an investor at Harpoon Ventures, he focuses on dual-use defense and deep tech portfolio companies while assisting with government GTM strategy. Last summer he helped incubate a defense startup as interim Chief of Staff from pre-seed through seed. Prior to business school, he defused bombs for the Navy, leading teams across Asia, Europe, and Africa. He holds a B.S. in Industrial & Systems Engineering from USC.
Seth Rhodes
Seth is a junior at Stanford University studying Mechanical Engineering. He has a strong passion for technology and the ocean, both lifelong interests shaped by growing up in the Bay Area. Seth has hands-on experience in the aviation industry, particularly working on electric vertical takeoff and landing (eVTOL) aircraft. He is excited to continue exploring the intersection of engineering and real-world innovation through cutting-edge applications.
Breno Casciello
Breno is a junior mechanical engineering student at Stanford University, specializing in mechanical design and prototyping at HydraStrike. His past experiences include work at Stanford’s Hypersonics, Propulsion and Energy Lab, as well as independent design of an autonomous hydrofoil surfboard.
Overview
Naval Undersea Warfare Center - U.S. Navy
Submarine Operators who are conducting undersea warfare cannot sustain combat operations against threats due to the limited inventory and capacity restrictions of the MK 48 Advanced Capability (ADCAP) heavyweight torpedo, opting for a new more cost-effective torpedo to be proposed that can be fired from different platforms.
Problem Sponsor
155
Original Problem Statement
Number of Interviews
The Problem
Before the Spring 2025 Hacking for Defense (H4D) course at Stanford University even began, the seeds of Team HydraStrike’s mission were already taking root. Andrew Couillard, a former Navy Explosive Ordnance Disposal (EOD) officer, had spent eight years on active duty. While stationed in Taiwan during the final years of his service, he saw firsthand the growing threat landscape in the Taiwan Strait. That experience raised concerns about a critical vulnerability: the U.S. Navy’s undersea warfare capabilities and its continued reliance on a single heavyweight torpedo, the aging Mark 48.
Recognizing that this Cold War-era weapon system was expensive, difficult to procure, and designed for one-to-one combat rather than the large-scale, multi-platform conflicts now likely in the Pacific, Andrew began exploring solutions through a research project at Stanford’s Gordian Knot Center. He partnered with a Pentagon strategic briefer to further investigate the issue.
Around the same time, mechanical engineering undergraduate students Breno Fabricio Casciello and Seth Rhodes and computer science students Gabriel Noya and Alex Wang were preparing to take the H4D course. They were searching for a meaningful and technically challenging problem to tackle. A mutual connection introduced them to Andrew and his research, and the five quickly aligned on a shared mission. They formed Team Hydra Strike and entered H4D with a clear purpose: to modernize the Navy’s torpedo systems in the face of evolving maritime threats.
Their sponsor, the Naval Undersea Warfare Center Newport (NUWC), stressed the urgency of the problem. The Navy’s continued reliance on the Mark 48 represented a significant strategic gap, one that Hydra Strike was determined to help address.
The Innovation
What followed was a deep dive into the Navy’s underwater weapons systems. Team HydraStrike’s exploration was driven by interviews with over 110 stakeholders during the class, and more than 155 total to date, including Navy commanders, submarine weapons officers, and defense strategists. They discovered that even in an ideal scenario, a submarine could only deploy 25 torpedoes before requiring a 3–4 day resupply, a major tactical limitation in high-tempo conflict with a numerically superior adversary.
“The Mark 48 was built for specific platform matchups, Cold War submarines versus Cold War submarines,” Casciello said. “That doesn’t scale when China has a 10:1 or even 15:1 vessel advantage.”
Team HydraStrike’s early “most viable products” (MVPs) included more affordable, scalable versions of the Mark 48, as well as loitering mine-like systems. But the real breakthrough came from integrating swarm logic into the undersea domain.
Their concept? A modular unmanned underwater vehicle (UUV) the size of a standard torpedo, deployable from existing submarine tubes, that serves as a “mother ship” carrying multiple mission-configurable payloads, including kinetic effectors for hard or mission kills, and first person view (FPV) drones or sensors for top-side strikes. This architecture enables distributed lethality and tactical flexibility, allowing commanders to adjust loadouts based on mission needs.
“We can either combine multiple smaller charges to deliver a single, powerful strike, or use them independently to target multiple assets at once,” explained Rhodes. “It’s not just replacing a torpedo; it’s redefining what underwater combat can be.”
The system is designed to be platform-agnostic and mission-flexible, increasing adaptability across various launch systems and engagement scenarios. The team’s “spider egg and spider bundle” concept, where smaller effectors detach from the UUV near the target, allows modular deployment without the explosive overkill or logistical burden of legacy systems. This approach gives the Navy greater tactical flexibility, enabling more precise, scalable responses to diverse undersea threats, without having to rely on a costly, one-size-fits-all weapon.
Presentation
Team HydraStrike’s Hacking for Defense Experience
Team HydraStrike credits H4D for transforming their understanding of the defense space and their approach to innovation. Coming from engineering and military backgrounds, they were attracted to the program’s unique combination of real-world impact and forward-leaning problem-solving.
Team HydraStrike’s Hacking For Defense Group
“We knew nothing about torpedoes at the start,” said Casciello. “H4D gave us the structure and access to talk to experts across the Navy and DoD ecosystem and iterate rapidly on those conversations.”
The team emphasized how H4D’s customer discovery-driven methodology pushed them to truly validate their insights and evolve their MVP. They also highlighted the value of the teaching team and network. “Getting weekly feedback from Steve Blank, Joe Felter, Steve Weinstein and Jeff Decker was like a startup bootcamp with national security stakes,” reflected Casciello.
Rhodes agreed, saying “We talked to three Vice and Rear Admirals, senior DoD mentors, and dozens of submariners. That kind of access doesn’t exist in any other class.” The relationships they built not only shaped their solution, but also gave them a clearer understanding of how real change happens within the Department of Defense. “I'd say a big thank you to all the people who have helped us. We wouldn't be 1% of the way we are now without the people who have helped us.”
Their biggest takeaway? “If you want to build something real that matters, start here (in the H4D classroom).”
What’s Next
Following H4D, Team HydraStrike is continuing full speed ahead. Andrew, Seth and Breno have joined the Defense Innovation Unit (DIU) pathway to secure maker funding to develop and validate their first prototype through the Defense Innovation Summer Fellowship - Commercialization (DISF-C) program. Working with Stanford’s Flow Physics Lab, they are currently testing the technical feasibility of combining multiple underwater charges into a single synchronized strike, and are in talks with Navy partners at NPS and Indian Head to simulate performance using official Navy software.
“With hardware, especially in defense, no one buys the vision alone,” said Rhodes. “You have to show it, make it real, and earn their trust.”
Their summer roadmap is focused on building a scale-down prototype to validate the technology and gain continued sponsor support. “We know the Valley of Death is real,” Casciello admitted. “But we also know we’ve got a solution that meets an urgent, unmet need. That’s what drives us.”