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TMAG: Bridging Experience, Innovation, and Dedication to Serve Warfighters and Communities.

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The Maritime Advisory Group

Who We Are

TMAG (The Maritime Advisory Group) was founded by Brendan McCullen, a Navy corpsman with extensive Marine Corps Special Operations experience. With 35 years of combined military and federal government expertise, TMAG bridges the gap between government procurement challenges and innovative solutions. We provide liaison, defense, and recovery services to deliver mission-critical tools and support where it’s needed most

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Our Mission and Core Values

To empower the United States government and its allies with innovative, reliable, and life-saving solutions by fostering connections, providing essential defense resources, and leading comprehensive recovery efforts after crises.

Integrity

Upholding the highest ethical standards in every partnership.

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Innovation

Delivering forward-thinking solutions to meet urgent, evolving needs.

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Commitment

Prioritizing the safety and success of warfighters and communities.

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Collaboration

Building trusted relationships to achieve exceptional results.

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Excellence

Ensuring every product and service meets exacting quality and compliance standards.

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Why Choose TMAG?

Credibility:

Founded by a Marine Corps veteran with firsthand warfighter experience.

Expertise:

Over three decades of military and federal government service.

Efficiency:

Streamlining procurement processes to deliver timely and compliant solutions.

Partnerships:

Trusted relationships with domestic manufacturers and vetted suppliers.

Mission-Driven:

Committed to enhancing warfighter survivability and rebuilding resilience in affected communities.

Meet Brendan McCullen

Meet
Brendan McCullen

Brenden McMullen is retired from both Active Duty and Government Service, with over 39 years of sworn service. Originally raised in the ground combat medical trades as a Navy Hospital Corpsman, he expanded his skill sets to include Reconnaissance, Diving, Parachute Operations and Instruction. He would later advocate for his entire community at senior levels for human talent recruitment and retention. After tours in the Infantry, Recon, EOD, Presidential Support, and Instructor Duty, he retired from an Acquisition support role, serving as a test parachutist and experimental diver.

Brenden was hired by NAVSEA for his advanced degree and experience in Emergency Management. He was instrumental in the implantation of the Navy Emergency Management Program, as well as the global implementation of Navy Dispatch and Emergency Operations Centers. After 15yrs of further duty, Brenden was inspired to form the Maritime Advisory Group to continue helping outside the constraints of the Military or Federal Service.
EDUCATION
Master of Science, Health Science: Emergency and Disaster Management.  Touro University International, Summa Cum Laude 

Bachelor of Science, Health Science.  Touro University International
Emergency Management – Graduate Degree and 15 years of senior-level experience as US Navy Civilian NAVSEA Employee. Capability Area Systems Engineer for EM in the NAVFAC Antiterrorism / Force Protection Ashore Program.

Project/Program Management – Expert in cradle-to-grave management from requirements development, through all funding phases into Sustainmen

Headquarters Level – Assistant Program Manager for policy and business decisions.

Master Training Specialist/Instructor – Qualified at the highest level of excellence as a Navy Instructor, with decades of experience.

Combat Arms – 22yrs experience in the projection of American Diplomacy through USMC Infantry and Reconnaissance

Medical – Battlefield treatment, education, owning/operating my own clinic.

Superb Communicator and Facilitator – Confident and persuasive; routinely briefs at executive/general officer levels as a subject matter expert. Identifies and resolves crises quickly and effectively.

Contracting Officer’s Representative – Manage >$5M in SEAPORT-E contracts

CHRONOLOGICAL PROFESSIONAL EXPERIENCE

2008-2024 – Federal Employee, NSWC Dahlgren, NSWC Indian Head
  • Section Head, Integrated Base Defense and AT/FP Z22
  • Lead Systems Engineer for EM/MED/CBRN – Lead, manage, forecast a global enterprise.
  • Capability Area Coordinator for DON CBRN Response and Recovery
  • Emergency Management SME
  • Project Officer for integration and fielding of CONUS and OCONUS Dispatch
  • Reviews and approves all new-equipment training curricula and materials.
  • Competed for and was awarded over $5M in RDTE funding for personally managed projects.
  • Review and approve (govt acceptance) for contract deliverables.
  • COR duties – Contract Officer’s Representative. Management and oversight of work won by partners in industry.
  • Provide oversight for 67 funded and unfunded projects in the EM Investment Plan
  • Publish training/education documents in support of new capabilities. Reviews and approves at policy levels.
  • Provide expert input on documents, briefs and policies regarding EM and Medical Response.
  • Prepare and present briefings at executive level management and project reviews.
  • Interface with industry leaders to examine and recommend new technology acquisition in all areas of EM and Medical Response.

The Crucible is the premier site for dynamic, realistic and high-risk training for US State Dept Security contractors and International Law Officers.

  • Provide expert instruction to US State Dept security contractors and International Law Officers deploying to various theatre sites. Instructional competencies include:
      Combat Trauma
      Marksmanship
      Tactical maneuver
      Close Quarters Battle
      M16/M4/M9/Glock19/AK47
      Ropes and suspension
      Theatre Orientation
      Medical Intelligence
  • Developed curriculum for other courses, including Emergency Actions in Embassies, Personal Protection, Surveillance Avoidance.
  • Range Safety Officer
2002-2006 Enlisted Technical Leader (ETL), Reconnaissance Corpsmen

Unique position of extreme accountability.  Sole POC for special operations medicine in USMC Reconnaissance.  Harness talent through aggressive recruiting strategies to maintain a highly and uniquely skilled job force.  Focus on recruitment, training, retention and deployment.

  • ETL position is a three year appointment by the Surgeon General to:
  • Compile and analyze data to forecast trends in casualties, healthcare delivery and combat medical readiness.
  • Develop and promulgate doctrine and policy concerning employment, growth, development, impact and needs of the community.
  • Advise Bureau of Medicine, Bureau of Personnel and Headquarters Marine Corps at senior executive/Flag levels.
  • Project long-term requirements for personnel and training. Coordinate a Tri-Service career-training pipeline over 14 months in duration.

MARCORSYSCOM is the lead agent for RDT&E, acquisition and life cycle management of new equipment designed to enhance the warfighting capability of the Operating Forces.

  • Test parachutist and experimental diver. Support program development and devise test plans with engineering staff. Substantial contributions in the following funded programs:
      Diver Propulsion Device – Test Director and diver
      Combat Display Dive Mask – Test Director and diver
      DARPA PowerSwim – Test Facilitator and diver
      Hydrographic Mapping Device – diver
      Multi-Mission Parachute System – Test jumper
      Special Application Parachute – Test jumper, P2 glider qualified
      HR 400 Reserve Parachute – Test jumper
      CYPRES Automatic Opening Device – Test jumper
      UH1Y Helicopter – SPECWAR tester
      MK48 Full Face Dive Mask – Test Facilitator and diver
      Combatant Diving Supervisor Crs – Course co-author
      Diver Propulsion Device Pilot Crs – Course co-author
      MCO 3500.20B – Co-author
  • Supervise and execute high-risk operations involving aircraft, boats, diving; testing equipment under extremely hazardous conditions.
  • Develop procedures and policy related to the use and deployment of life-support equipment.
  • Recon Independent Duty Corpsman. Introduce safety measures, routine and acute healthcare during daily operations.

NDSTC is the worldwide center for diving excellence, and trains hundreds of professional divers from U.S. and Allied Forces.

High – Risk Instructor
  • Responsible for the delivery of extremely rigorous academic and physical curricula involving the safe conduct of military open and closed-circuit diving. Courses taught: Marine Combatant Diver, Amphibious Recon Corpsman, Underwater Construction Team/Army 2/C, Army 1/C, Navy 2/C.
  • Chief Instructor for the diagnosis and treatment of diving disorders, to include hyperbaric therapy (HBO2) and neurological examination, basic and advanced diving skills with focus on man-carried diving apparatus (SCUBA/MK25)
  • Command Equal Opportunity Officer, responsible for education and execution of the DoD EO Policy; to protect the integrity of the organization through pro-active EO awareness.
  • Supervise 20 senior instructors
  • Develop, critique, implement, deliver and revise every aspect of any curricula.
  • Personally enhanced military diving by the grassroots implementation of a highly successful joint-service training program for Army Diving Supervisors, resulting in official course execution and personal decoration.
1997-2000 PRESIDENTIAL RETREAT, CAMP DAVID
Camp David provides the First Family and distinguished guests with a         secure five- star recreational facility and national command post.
  • Medical Officer / Department Head. Coordinated and delivered routine, acute and emergency medical care for crewmembers and dependents, Secret Service, Presidential staff and the First Family. Supervised 4 healthcare providers and managed a patient population of over 400 in a remote setting, without a Medical Officer.
  • Review/Supervise the Medical Training Plan for the entire staff.
  • Implemented 1st Responder Training for over 200 dedicated staff, ranging from ambulance operations to advanced medical techniques.
  • Contingency Planner. Completely renovated the medical capability of classified contingency facilities, a multi-million dollar project.
  • Director of Emergency Services. Coordinated and executed advance Presidential contingency plans for medical and emergency response. Managed a large classified budget and sensitive equipment.
  • Athletic Director. Promoted health and fitness by organizing spectacular athletic events, including a 50km race, a wilderness triathlon, and numerous team-based sports.
  • Top Secret Clearance (TS – Yankee White program)

Explosive Ordnance Disposal Mobile Unit THREE enables access by providing expeditionary EOD forces for the location, identification, rendering safe, recovery, and disposal of explosive ordnance, to include chemical, biological, radiological and nuclear.

  • Chief Trainer and Veterinary Technician. Responsible for the training, care and health of over 30 marine mammals valued at over $100M.
  • Diving Supervisor. On record as the busiest supervisor in the US Navy during CY 1995, supervising hundreds of incident-free, high-risk dives in support of Mine Countermeasure operations.
  • Medical Dept Representative and diving med tech. Conducted 14 recompression treatments of stricken divers, all with full recovery and return to diving duty.
  • Static line and Freefall Jumpmaster. Supervised all aspects of parachute operations, to include training and doctrine development.

Force Recon is the USMC’s special missions arm, conducting pre-assault and distant post-assault reconnaissance in support of Division and MEF operations.  We employ specialized equipment, advanced field and tradecraft skills and are referred to as the Silent Professionals.

  • Platoon Corpsman. Solely responsible for the health and welfare of 22 platoon members. Collect, analyze, and implement medical intelligence. Practice preventive medicine, acute care, and long-term health management.
  • Conduct combat medical training from basic lifesaving to advanced intervention.
  • Maintain advanced skills in job-specific trade and fieldcraft, to include: reconnaissance/surveillance, coordinating arms, weapons, direct action, communications and cryptology, navigation and maritime operations, patrolling and demolitions.
  • Conducted real-world/real-time pre-assault and distant post-assault reconnaissance in support of intelligence requirements for MEU/DIV/MEF level operations during Operations Desert Shield/Storm.
  • Static line and Freefall Jumpmaster. Supervised all aspects of parachute operations, from aircraft to drop zone.
  • Open Circuit Diving Supervisor
  • Decorated for Valor during combat operations in Desert Shield/Desert Storm.

Military credentials, training and decorations available on request

Employment experience prior to 1990 included 2 yrs in 3rd Reconnaissance Bn, , a 3yr tour in 1st Bn, 3rd Marines, and 2yrs at Naval Hospital, Beaufort SC.  There was no significant work experience prior to my military service.

Join Us in Making a Difference

Learn more about TMAG’s mission and how we serve warfighters, government agencies, and communities worldwide. Together, we can empower those who defend us and rebuild resilience where it’s needed most.

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