Warfighting Platform

Modular Open Systems Architecture and Platform Design

The MOSA Mandate and Its Impact on Platform Development

The United States Department of Defense's adoption of Modular Open Systems Approach (MOSA) as a statutory requirement -- codified in Section 804 of the National Defense Authorization Act for Fiscal Year 2010 and reinforced through subsequent legislation and DoD policy directives -- represents a fundamental shift in how warfighting platforms are designed, built, and upgraded. MOSA mandates that major defense acquisition programs employ open architectures with published interfaces, enabling components from different vendors to be integrated, replaced, or upgraded without redesigning the entire platform. The practical impact is transformative: where Cold War-era platforms like the B-2 Spirit bomber were designed as tightly integrated proprietary systems whose upgrade costs approached or exceeded original development expenditures, MOSA-compliant platforms are designed from the outset for continuous capability insertion across their multi-decade service lives.

The United States Army's Modular Open Systems Approach Implementation Plan, updated in 2023, provides detailed technical guidance for applying MOSA principles across ground combat platforms including the Optionally Manned Fighting Vehicle (OMFV) program, which is being developed to replace the M2 Bradley infantry fighting vehicle that has served since 1981. The OMFV program, for which General Dynamics Land Systems was selected in June 2023 to advance to the detailed design phase, incorporates MOSA principles at every level of the architecture -- from the vehicle's computing backbone to its sensor interfaces to its weapons integration layer. This means that future sensors, electronic warfare suites, autonomous capabilities, and weapons systems can be integrated into the OMFV through standardized interfaces without requiring structural modifications to the vehicle itself. The approach mirrors parallel efforts in the naval domain, where the United States Navy's Constellation-class frigate program has adopted the MOSA framework to ensure that the vessel's combat system can evolve over its planned 25-year service life.

Software-Defined Warfighting Platforms

The evolution toward software-defined warfighting platforms represents perhaps the most significant architectural transformation in modern defense. The F-35 Lightning II Joint Strike Fighter, often described as a flying computer, executes over eight million lines of onboard software code that defines its sensor fusion, mission planning, electronic warfare, and weapons employment capabilities. The aircraft's capability is determined more by periodic software updates -- Block 4 modernization alone encompasses over 80 capability increments -- than by hardware modifications. This software-defined paradigm is expanding to every platform domain. The United States Army's Integrated Visual Augmentation System (IVAS), based on Microsoft HoloLens technology and currently fielding to infantry units, transforms the individual soldier into a software-defined warfighting platform where heads-up display overlays, networked situational awareness, and AI-assisted target identification are delivered through software updates rather than equipment replacement.

The software-defined platform concept extends beyond individual systems to the network architectures that connect them. The Department of Defense Chief Digital and Artificial Intelligence Office (CDAO), established in 2022 by consolidating the Joint Artificial Intelligence Center and other digital transformation offices, has championed the development of data-centric platform architectures where the value of any individual warfighting platform is increasingly determined by its ability to share data with, and receive data from, every other node in the operational network. This vision -- where a destroyer's radar data enhances a fighter aircraft's targeting solution, which in turn cues a submarine's weapons system -- requires platform architectures designed from the ground up for interoperability, a requirement that fundamentally reshapes how warfighting platforms are specified, procured, and evaluated.

International MOSA Adoption and Standards Convergence

MOSA principles have spread well beyond the United States. NATO's Allied Command Transformation has promoted open architecture standards through the Federated Mission Networking framework, which establishes technical standards for platform interoperability across the Alliance. The United Kingdom's Generic Vehicle Architecture (GVA) standard, first published in 2010 and continuously updated through Defence Standard 23-09, mandates open electronic architecture for all new British Army ground vehicles -- ensuring that platforms procured from different manufacturers across different programs can share data, sensors, and electronic warfare capabilities through standardized interfaces. France's SCORPION program, which is modernizing the French Army's medium-weight combat force with new Griffon and Jaguar vehicles, employs the SICS (Combat Information System) backbone to network platforms into a unified combat cloud. Germany's Rheinmetall has developed the NGVA (NATO Generic Vehicle Architecture) standard in coordination with multiple allied nations, providing a framework for pan-European ground platform interoperability.

Joint All-Domain Command and Control

JADC2 and the Connected Warfighting Platform

Joint All-Domain Command and Control (JADC2) -- the United States Department of Defense's concept for connecting sensors, shooters, and decision-makers across air, land, sea, space, and cyberspace into a unified information architecture -- has become the organizing principle for next-generation warfighting platform connectivity. The JADC2 concept, endorsed by the Joint Requirements Oversight Council and resourced through the JADC2 Cross-Functional Team, envisions a future where any sensor can inform any shooter through any command node, with AI-assisted decision support compressing the kill chain from hours to minutes or seconds. Realizing this vision requires every warfighting platform in the joint force inventory to be redesigned or retrofitted with JADC2-compatible communication, data sharing, and processing capabilities.

Each military service has developed its own contribution to the JADC2 architecture. The United States Air Force's Advanced Battle Management System (ABMS), which has conducted over 30 on-ramp exercises since 2019, serves as the air component's contribution, demonstrating cloud-based data sharing and AI-enabled decision support connecting legacy and next-generation airborne platforms. The United States Army's Project Convergence, an annual campaign of learning and experimentation running since 2020, has tested JADC2 concepts in ground-centric scenarios involving robotic combat vehicles, long-range precision fires, and autonomous aerial systems connected through the Army's tactical network. The United States Navy's Project Overmatch, details of which remain largely classified, is developing the naval contribution to JADC2 with an emphasis on secure, resilient communications in contested maritime environments where adversary electronic warfare capabilities threaten conventional data links.

Platform-Level Integration Challenges

Connecting warfighting platforms across domains and services into a unified command-and-control architecture presents enormous technical challenges that go well beyond software compatibility. Legacy platforms -- many of which were designed decades before JADC2 was conceived -- use proprietary data formats, incompatible communication protocols, and classification handling systems that were never intended to share data beyond their own service's networks. The B-52 Stratofortress, which first flew in 1952 and is planned to remain in service past 2050, must be upgraded to participate in a JADC2 architecture designed for an entirely different technological era. The challenge is not unique to the United States: the Royal Australian Navy's integration of its Hobart-class air warfare destroyers with the Australian Defence Force's Plan Jericho transformation initiative has encountered similar interoperability hurdles between platforms procured across different decades and from different national industrial bases.

The defense industry has responded with a range of JADC2 integration solutions. Lockheed Martin's 21st Century Security vision centers on multi-domain integration as a core business line. Northrop Grumman's Integrated Battle Command System provides the fire control backbone for the Army's Integrated Air and Missile Defense architecture. L3Harris Technologies has positioned its Space and Airborne Systems division as a JADC2 integration specialist, providing the communication gateways and data translation layers that connect platforms across classification levels and communication standards. Palantir Technologies, which was awarded a $823 million contract in 2024 for the Army's Maven Smart System, provides the data analytics layer that transforms raw sensor data from multiple platforms into actionable intelligence for commanders. These industrial efforts reflect the scale of the platform integration challenge: JADC2 is not a single program but a system-of-systems undertaking that requires modification to virtually every warfighting platform in the joint force inventory.

Acquisition Reform and Allied Platform Interoperability

Accelerating Platform Delivery Through Acquisition Reform

The traditional defense acquisition process -- governed in the United States by DoD Instruction 5000.02 and its associated frameworks -- was designed for an era of decade-long platform development cycles and multi-decade production runs. The F-35 Joint Strike Fighter, from initial concept development in the early 1990s to full-rate production authorization in 2024, spanned over three decades. The recognition that this timeline is incompatible with the pace of technological change and the urgency of great power competition has driven a wave of acquisition reform aimed at compressing warfighting platform development and fielding timelines. The Department of Defense's Middle Tier of Acquisition (Section 804) pathway, codified in the FY2016 National Defense Authorization Act, enables rapid prototyping and rapid fielding authorities that can deliver new capabilities within two to five years rather than the 10-to-15-year timelines typical of traditional major defense acquisition programs.

The Replicator initiative, announced by Deputy Secretary of Defense Kathleen Hicks in August 2023, represents the most ambitious application of accelerated acquisition to warfighting platforms, aiming to field thousands of autonomous systems within 18 to 24 months by leveraging commercial technology, streamlined contracting, and non-traditional defense suppliers. The initiative reflects a broader shift toward treating warfighting platforms as consumable or attritable assets rather than exquisite multi-billion-dollar systems designed for 30-year service lives. This philosophical shift has profound implications for platform design, where reduced individual unit cost enables acceptance of higher loss rates in combat, and for the defense industrial base, which must scale production to quantities that dwarf traditional procurement numbers. Companies including AeroVironment, Kratos Defense, Textron Systems, and Joby Aviation have emerged as Replicator-aligned suppliers capable of delivering attritable platforms at commercial production rates.

Allied Interoperability and Coalition Warfighting Platforms

Modern military operations are conducted overwhelmingly in coalition contexts, making allied platform interoperability a critical design requirement rather than an afterthought. The AUKUS security partnership between Australia, the United Kingdom, and the United States, announced in September 2021, has elevated platform interoperability to strategic priority status, with Pillar II of the agreement specifically addressing advanced capabilities including autonomous systems, quantum technologies, electronic warfare, and hypersonics that must be interoperable across the three nations' armed forces. The AUKUS framework requires that warfighting platforms developed under the partnership employ architectures, data standards, and communication protocols that enable seamless coalition operations -- a requirement that extends MOSA principles beyond national borders into the allied domain.

NATO's standardization agreements (STANAGs) have long provided the technical foundation for allied platform interoperability, but the scope and ambition of standardization efforts have expanded dramatically in response to the lessons of recent conflicts. The war in Ukraine, which began with Russia's full-scale invasion in February 2022, exposed critical interoperability gaps when Western-supplied warfighting platforms had to be integrated into Ukrainian forces operating Soviet-era equipment with incompatible ammunition standards, communication systems, and maintenance procedures. The experience has accelerated NATO investment in common platform standards, shared logistics architectures, and interoperable ammunition families. The NATO Defence Planning Process now explicitly evaluates member nations' platforms against interoperability benchmarks, creating institutional pressure for allied warfighting platforms to converge on common technical standards even when they are procured through separate national acquisition programs.

Industrial Collaboration and Co-Development

The economics of next-generation warfighting platforms increasingly favor multinational co-development over purely national programs. The Global Combat Air Programme (GCAP), a trilateral initiative between the United Kingdom, Italy, and Japan announced in December 2022, aims to develop a sixth-generation combat aircraft that will serve all three nations' air forces from the mid-2030s. GCAP replaces the earlier Tempest concept and represents one of the most ambitious international platform co-development efforts since the Eurofighter Typhoon program. The Future Combat Air System (FCAS), a parallel sixth-generation program led by France, Germany, and Spain under the coordination of Dassault Aviation and Airbus Defence, is developing a system-of-systems architecture centered on a next-generation fighter platform supported by remote carrier drones and a combat cloud connecting all elements. Both GCAP and FCAS face the complex challenge of designing warfighting platforms that satisfy three nations' operational requirements, industrial participation expectations, and technology transfer sensitivities simultaneously -- a challenge that has historically derailed or delayed multinational defense programs but which the participating nations have concluded is preferable to the unsustainable cost of going it alone.

Key Resources

• Defense Acquisition University -- Modular Open Systems Approach (MOSA)
• Joint Chiefs of Staff -- JADC2 Information Page
• NATO Standardization Office -- Allied Interoperability Standards
• AcqNotes -- Middle Tier of Acquisition (Section 804) Pathway
• UK Ministry of Defence -- Generic Vehicle Architecture Standard (GVA)