By Robbin Laird
At the heart of Marine aviation’s drive for combat excellence lies a semi-annual event that most outsiders have never heard of, yet which one senior MAWTS-1 Commanding Officer described in unambiguous terms: WTI is where the United States Marine Corps comes together every year to train for war. That statement, offered by Colonel Wellons during a 2016 visit, captures with precision what the Weapons and Tactics Instructor (WTI) Course represents — not merely a training exercise, but the central mechanism through which Marine aviation continuously transforms itself, refines its tactics, integrates new platforms, and tests new concepts of operation under realistic combat conditions.
Marine Aviation Weapons and Tactics Squadron One (MAWTS-1), based at Marine Corps Air Station Yuma, Arizona, runs two of these WTI courses each year. Each course lasts approximately seven weeks. Together they constitute the most significant recurring training and innovation event in Marine Corps aviation, drawing hundreds of students, thousands of maintenance personnel, and scores of aircraft from across the Marine Corps and beyond. Understanding what actually happens during a WTI — the events that compose it, the scale it achieves, the problems it solves, and the innovations it generates — is essential to understanding how MAWTS-1 functions as what Laird and Timperlake have called an incubator for military transformation.
The Scale and Structure of a WTI
MAWTS-1 in its steady-state configuration is a squadron of approximately 200 total personnel, roughly half of them officers. That number is deliberately modest — it is a cadre force, a training institution, not a line squadron. But during a WTI course, the installation at Yuma is transformed. For the first WTI course of one representative year described in the book, 236 students were involved. With them came an additional 92 aircraft, more than 4,000 maintenance personnel, and the generation of approximately 2,350 sorties over the course of the event.
The sheer concentration of aviation power at Yuma during a WTI is itself a significant feature of the event. As Captain Fields, one of the Ground Combat Element leaders at MAWTS, put it: We get a MEBs worth of aircraft for a WTI course, which is something our ground combat forces will not normally see. That concentration — a Marine Expeditionary Brigade’s worth of aviation assembled in one place for a sustained period — is not accidental. It is the enabling condition for the kind of large-scale, integrated, multi-platform tactical training that cannot be replicated in the normal operational tempo of fleet Marine forces. Students from across the Corps arrive, many of them fresh from operational deployments, bringing with them the most current lessons from real-world combat environments.
The formal curriculum of the WTI course covers the full spectrum of Marine aviation mission sets. These include offensive air support, control of aircraft and missiles, assault support, aerial reconnaissance, anti-air warfare, electronic warfare, and aviation ground support. Critically, ground combat element personnel participate alongside aviators. For the first two weeks of the seven-week course, infantry and fire support Marines study the same curriculum and are held to the same academic standards as the aviation students. The goal, as articulated by Major Green of MAWTS’s Ground Combat team, is straightforward: We will return them to their units in seven weeks and we are going to return a subject matter expert on integration between air and ground assets.
Training the Trainer: The WTI Philosophy
The foundational philosophy of the WTI course is encapsulated in a phrase that appears repeatedly in discussions at MAWTS-1: training the trainer. The WTI course does not produce line pilots or infantrymen. It produces the instructors, tacticians, and subject matter experts who return to their units throughout the Marine Corps and the broader joint force and disseminate what they have learned. A Marine who earns the WTI designation does not simply receive knowledge — he or she becomes a carrier of it, a node in a distributed knowledge network designed to raise the tactical competence of the entire aviation enterprise.
This philosophy has direct implications for how the WTI events are designed. The scenarios, exercises, and tactical events that fill the seven weeks of a WTI are not designed merely to test students — they are designed to teach them something they could not have learned in their home squadrons. The deliberate construction of complex, multi-platform, multi-domain tactical problems forces students to encounter situations that stretch their existing competence and require them to develop new mental models for how to integrate diverse aviation and ground assets. When they return to their units, those mental models travel with them.
The complementary mechanism for keeping the course current is the continuous flow of combat experience into MAWTS-1 itself. As Major Seich explained during an early visit to the squadron: The students coming through the course have just come from recent combat experience. And we send MAWTS instructors to combat theaters for about a month at various points and they bring back lessons learned. This bidirectional flow — real-world experience coming in from the fleet and from deployed instructors, refined knowledge going back out through WTI graduates — is what keeps the course from becoming an academic exercise disconnected from the operational realities of the force.
WTI Events as Tactical Laboratories: The AAW and Other Major Exercises
Within the broader WTI course structure, a series of specific tactical events serve as the primary vehicles for learning and innovation. These events vary in their focus — some emphasize air-to-air warfare, others ground support, others assault support or electronic warfare — but all share the characteristic of assembling large, realistic combined arms forces against credible adversary representations.
One of the most revealing descriptions of these events in the book comes from Major Roger “HASMAT” Greenwood, a key architect of the F-35B’s integration into MAWTS, describing the introduction of the new aircraft into WTI exercises. The first significant WTI event flown by the F-35B at MAWTS was called AAW2 — a large defensive counter-air event. As Greenwood described it: AAW2 is an air-to-air event defending high value ground based MAGTF assets from a threat strike. The F-35s integrated with F-18s and a notional Patriot battery against adversaries, which included F-18s, F-5s, AV-8s, EA-6Bs, and B-1Bs.
What happened in that event was, by Greenwood’s account, eye-opening. Even operating in a Block 2A configuration — an early and limited software iteration — the F-35B’s sensor suite demonstrated capabilities the Hornets around it simply did not possess. The fidelity of the radar is amazing, Greenwood noted. We can see things that the Hornets were not able to see. The ability to pass that information via voice to the accompanying F-18s, and the anticipation of doing so via datalink as software matured, illustrated a new model of how fourth and fifth generation aircraft could work together: the F-35 as a sensor node and battle manager, the F-18 as an additional shooter empowered by the F-35’s awareness.
This dynamic — the WTI event as a venue for discovering and then codifying new multi-platform integration concepts — illustrates something important about what the exercises are designed to achieve. They are not simply tests of existing doctrine. They are opportunities to develop doctrine that does not yet exist, to encounter problems that have not been anticipated in any classroom, and to begin working out solutions under conditions of realistic pressure. The debriefs that follow each WTI mission exercise are where that learning is formally captured. As Colonel Wellons noted: When we come back from a typical WTI mission exercise and we debrief it with the helo and fixed wing guys and the C2 guys and the ground combat guys, more often than not it is the F-35 which is identified as the critical enabler to mission success.
Integrating New Platforms and Concepts: The WTI as an Innovation Engine
The WTI course is not simply a venue for exercising established capabilities. It is, with striking consistency across the decades covered by Laird and Timperlake’s book, the primary venue in which new platforms are integrated into the MAGTF at the tactical level. The pattern is repeated with the Osprey, the F-35B, the G/ATOR radar, the CAC2S command and control system, and a succession of unmanned systems and electronic warfare capabilities. When a new system arrives at Yuma, it does not simply become an additional element in an existing exercise. It generates new tactical problems that force the entire exercise architecture to evolve.
An instructive example from the 2018 WTI course involves Distributed STOVL Operations (DSO) — the concept of using the F-35B’s vertical landing capability to operate from expeditionary forward arming and refueling points (FARPs) far from established bases. During one WTI event, a KC-130J took off carrying Marines, ordnance, fuel, and a security team. They landed at a remote facility, established two forward arming and refueling points and a defensive perimeter. Shortly thereafter, two F-35Bs landed, received hot fuel and hot-loaded ordnance, then took off and executed their assigned missions. The conceptual and procedural framework for this kind of distributed basing was being worked out in real time, under the pressure of the exercise, by the pilots, maintainers, and logistics Marines who would have to execute it.
The WTI course was also the venue for a procedural innovation that would have significant operational implications: the development of hot-loading procedures for the F-35B. As Wellons recounted: One example has been something we did in the last WTI class, namely hot loading of the F-35 as we have done with the F-18 and the Harriers in the past. We worked with NAVAIR and with China Lake and Pax River and came up with a set of procedures to do the hot load of an F-35. We did it successfully at this last WTI class, and it significantly shortens the turn time between sorties. The innovation was not born in a laboratory or a requirements office. It was born in a WTI exercise, tested under realistic conditions, and validated through the iterative process of doing and debriefing that defines the WTI approach.
By 2017, a key WTI focus had shifted toward what the book describes as integrated fire control — specifically the integration of the G/ATOR ground-based radar with the F-35’s airborne sensor suite and the CAC2S command and control architecture. As MAWTS officers described it, the goal was to maximize three core systems — G/ATOR, the Composite Tracking Network (CTN), and CAC2S — as they were fielded to the force for the first time as a systemic whole. The WTI provided the venue for testing how these systems could be used in combination to provide targeting information to multiple shooters simultaneously, whether airborne, shipborne, or ground-based. A key challenge identified during those exercises was changing the mindset of Marines conditioned by legacy systems to understand and adopt new tactics, techniques, and procedures for platforms whose full potential had not yet been conceptually grasped.
The Contested Environment: Preparing for High-End Threats
The evolution of the WTI course from its origins in the post-Vietnam era to its contemporary form tracks the evolution of the threat environment that Marine aviation must prepare to operate in. The earlier WTIs of the 1980s and 1990s were shaped by Cold War scenarios and the requirement to operate against Soviet-supplied integrated air defense systems. The WTIs of the 2000s and early 2010s were heavily influenced by the demands of counter-insurgency operations in Iraq and Afghanistan, where the threat was asymmetric and the premium was on close air support and persistent surveillance rather than high-end air-to-air combat or penetration of sophisticated air defense networks.
The shift back toward contested, high-end threat environments is visible throughout the WTI courses described in the book’s later chapters. By the time Colonel Wellons was completing his tenure as MAWTS-1 commanding officer, the WTI course had been deliberately redesigned to confront students with the most sophisticated and capable adversary representations available. As Wellons described it: We have challenged our students, especially this year, to operate in environments where communications and navigation systems are challenged, facing the most sophisticated and capable adversaries we can find. We focused on the idea that in the future fight, our primary means of navigation and communication will probably be denied, and certainly degraded, and our operators may have to use old-fashioned techniques to get bombs on target.
This emphasis on operating in degraded and disrupted environments became a defining characteristic of the WTI course as the Marine Corps shifted its strategic focus toward the Pacific and the challenge of peer competition. The electronic warfare dimension of WTI events expanded significantly, with multiple joint community participants bringing advanced EW capabilities to play. MAWTS officers described the goal as getting Marines to proactively think about how an adversary will conduct battle so that strengths can be countered and weaknesses exploited — a fundamentally different cognitive demand from the permissive environments of the land wars.
Joint and Allied Integration: The WTI Beyond the Marine Corps
The WTI course has never been an exclusively Marine Corps affair, and the book makes clear that joint and allied participation is a feature rather than an afterthought. The joint training money that flows through the Joint Training Capability Fund (JTCF) is integral to the WTI’s ability to assemble the adversary forces necessary for realistic exercise scenarios. As Major Seich explained in an early interview: The Marine Corps does not have enough fourth-generation aircraft adversaries for our exercises. We bring down USN and USAF platforms to play that role. Those platforms have included F-22s from Nellis, which have on multiple occasions participated as augmented blue force assets — a fact that speaks to the unusual complexity of the scenarios that the WTI course constructs.
Allied participation has extended the WTI’s reach beyond the joint community. The United Kingdom, Australia, Canada, and Israel have all sent participants to WTI events. That international participation reflects both the quality of the course and the relationships it builds — allies who have trained alongside MAWTS-1 graduates understand the concepts and the language of Marine aviation integration in ways that make future combined operations more effective. The integration with the USAF weapons school at Nellis has become particularly close over time, with the F-35 serving as an accelerant. By the time of Colonel Wellons’ final year in command, MAWTS-1 had a former USMC F/A-18 instructor pilot flying F-35As on exchange with the USAF Weapons School, and the first USAF F-35 exchange pilot was inbound to Yuma.
Naval integration has been a persistent and growing emphasis. The relationship with Naval Strike and Air Warfare Center at Fallon evolved over the period covered by the book, with the Navy on a somewhat later timeline than the Marine Corps in terms of F-35 integration but clearly converging. The development of joint communications standards — what the book describes as ASLA joint communications standards — involved cooperation among all the service weapons schools, MAWTS-1 among them. The aspiration, articulated repeatedly by MAWTS officers, was a distributed maritime and air force that could operate seamlessly across service lines, with the F-35’s sensor fusion and data distribution capability serving as the connective tissue.
The Maintenance Dimension: AAMOC and the WTI’s Expanding Scope
An important evolution in the WTI course that the book documents in some detail is the expansion of its scope beyond the pilot and operator community to encompass the maintenance and sustainment enterprise. This expansion reflects a fundamental insight: in modern aviation, the readiness of aircraft is as operationally decisive as the skill of the pilots who fly them, and the WTI course was not fully realizing its potential as a transformation vehicle if it was not also transforming how Marines think about and practice maintenance.
In 2017, a new course called the Advanced Aircraft Maintenance Officers Course (AAMOC) was added to the WTI. Running concurrently with the main WTI course for the same seven-week period, AAMOC represents a graduate-level program for professional aircraft maintenance officers — described by its developers as the first of its kind in the Marine Corps. The course includes approximately 62 hours of academic coursework, daily evaluations, capstone projects developed by students around problems of their own choosing, and a grade standard of 80 percent to graduate. Its graduates are designated Maintenance and Training Instructors (MTIs).
The WTI period is an ideal time to run AAMOC precisely because of the concentration of maintenance expertise that the course naturally assembles. As Captain Campbell, one of the course’s developers, explained: The maintainers come to Yuma as if on a deployment. They are in barracks together and they generally do not know one another. They cross-learn during their time at WTI. That cross-learning — gray beards with decades of experience on a single platform encountering new arrivals with fresh perspectives and new questions — creates the kind of generative friction that drives standardization of best practices while leaving room for the innovations that come from challenging established ways of doing things.
Innovation Driven from the WTI: Not Wargaming, but Warfighting
One of the most important characterizations in the book comes from a 2020 passage on the role of MAWTS-1 in the Marine Corps’ digital transformation: at MAWTS-1, innovation is driven by the work done in the WTIs, not in wargaming. That distinction matters enormously. Wargames produce intellectual constructs. WTI events produce validated concepts — ideas that have been tested against the friction of actual operations, against real aircraft that can and do fail, against students who carry the biases and habits of their home squadrons, and against the unexpected problems that emerge whenever complex systems and human beings interact under pressure.
The WTI course creates what might be described as a living laboratory for operational concept development. When NAVAIR engineers want to understand how the F-35’s maintenance system interacts with the broader Marine Corps IT architecture in a deployed environment, they come to WTI. When the ADT&E Department at MAWTS wants to develop TTPs for integrating Group 4 and Group 1 unmanned aerial systems into both offensive operations and layered defense against threat UASs, they develop and test those TTPs during WTI events. When the question of how to manage Integrated Fire Control between the G/ATOR radar and the F-35 needs to be answered in operational terms rather than theoretical ones, the WTI course is where the answer is found.
Major Shoop, the F-35B lead at MAWTS during the initial integration period, captured this dynamic well when he described what it meant to have a sensor-rich integrated platform entering the WTI course for the first time. The prior approach had treated electronic warfare as an external asset. Now EW was embedded in the cockpit of the tactical aircraft itself. That was a major conceptual shift — and it was the WTI course that created the conditions under which that shift could be absorbed, tested, and translated into teachable tactics.
Conclusion: The WTI as the Beating Heart of Marine Aviation
Reading through the decades of MAWTS-1 history captured in Laird and Timperlake’s book, one is struck by how consistently the WTI course functions as the beating heart of Marine aviation innovation. New platforms arrive. New threats emerge. The strategic environment shifts. Force design changes imposed from above — including the sweeping and contested changes of Force Design 2030 — alter the aviation structure with which the Marines must work. Through all of it, the semi-annual WTI course provides a persistent mechanism for absorbing those changes, testing new approaches, and generating the validated concepts that keep the Marine Corps ready for the next fight.
The WTI’s power derives not from any single event within it but from the cumulative effect of its design. The training of trainers who return to the fleet. The debriefs that follow each mission event and force honest assessment of what worked and what did not. The presence of students who bring the freshest combat experience available. The joint and allied participants who stress-test Marine concepts against a wider range of capabilities and perspectives. The co-location of aviation and ground combat students who must learn to think across the air-ground boundary. The maintenance professionals developing best practices under the pressure of a realistic deployment analog. All of these elements reinforce each other in a system that is more than the sum of its parts.
The first and eighth Commanding Officers of MAWTS-1, interviewed on the day of the 2024 change of command ceremony, described their approach to combat innovation in terms that sounded strikingly identical despite the decades separating their tenures: insert technology into concepts of operations rather than having technology exist outside the organizational changes needed to use it, and let warfighters drive innovation rather than contractors or acquisition officials. Two hours later, Colonels Purcell and Smith described the same mentality with different technologies and a different threat environment. That continuity — that institutional DNA maintained across nearly five decades — is what the WTI course embodies and perpetuates. It is why MAWTS-1 has been, and remains, an incubator for military transformation.
This article introduces a series on WTI-2-26 which is written derived from the photographic record released by the command.
For our book from which this analysis is derived, see the following: