The Undersea Systems Division at Leidos currently has an opening for a Senior Mechanical Engineer/Technical Writer for an existing and growing program. Candidate will join a fast-paced engineering group rapid-prototyping unresolved and emergent requirements for a critical Department of Defense project managed by the Naval Information Warfare Center (NIWC) Pacific. It provides deployable radiation sensors and monitoring systems to counter Weapons of Mass Destruction (WMD) across land, maritime, and aerial environments.

Primary Responsibilities:

• Translate complex engineering specifications, sensor capabilities, and system behaviors into user‑friendly language while preserving technical precision.
• Develop and maintain technical documentation for radiation detection and monitoring systems with little support from the sensor designer
• Document system architectures, interfaces, workflows, and data pathways for radiation sensing
• Support updates to documentation as system hardware, firmware, and software evolve across RADIAC product lines.
• Ensure all documents comply with DoD, Navy, and NIWC Pacific standards, including required formatting, terminology, and security markings
• Produce briefs, fact sheets, and stakeholder‑facing communications that describe mission context, operational capabilities, and deployment scenarios.
• Manage version control for technical documents and ensure proper storage within approved configuration management systems
• Review and edit existing documentation for clarity, consistency, and compliance with RADIAC program requirements

Basic Qualifications

• U.S. Citizen with ability to obtain SECRET security clearance.
• Knowledge of Systems engineering principles, including system architectures, interface control, requirements traceability, and configuration management.
• Ability to read, understand, and interpret complex technical documents.
• Ability to communicate complex ideas in writing, orally and visually.

Preferred Qualifications

• Basic familiarity with radiation detection technologies, fielded sensing systems, and environmental monitoring principles
• Knowledge of test and evaluation processes for complex DoD systems, including developmental testing, operational testing, and verification/validation methodologies.
• Knowledge of test facility design, operations, and maintenance (O&M), especially for radiation sensing, environmental simulation, or specialized instrumentation labs
• Knowledge of DoD‑specific documentation standards, technical writing practices, security classification guidance, and formatting requirements.
• Ability to translate engineering notes, phone calls, schematics into technical documentation for high level management.

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Original Posting:

July 21, 2026

Pay Range:

Pay Range -

The Leidos pay range for this job level is a general guideline only and not a guarantee of compensation or salary. Additional factors considered in extending an offer include (but are not limited to) responsibilities of the job, education, experience, knowledge, skills, and abilities, as well as internal equity, alignment with market data, applicable bargaining agreement (if any), or other law.