Facilities Mechanical Engineer

Leidos•Chantilly, VA

About The Position

Facilities Mechanical Engineer – Mission-Critical Facilities Design Leidos is seeking a driven and detail-oriented Junior level Mechanical Engineer to support the planning, design, and analysis of mechanical systems—primarily Heating, Ventilation, and Air Conditioning (HVAC)—for secure, mission-critical operations across government, commercial, and institutional facilities. This is a growth-focused role where you’ll work alongside senior engineers to develop high-performance, energy-efficient, and code-compliant systems that support 24/7 operations. We are able to sponsor the clearance process for qualified candidates; however, our preference is to onboard individuals who already hold an active clearance at any level. This role supports a TS/SCI with Polygraph, and Leidos can maintain that clearance for the position. This role may be eligible for a sign-on incentive, which could include additional PTO or a monetary bonus. What You’ll Do Help figure out the design and layout of HVAC systems, including ductwork, piping, ventilation, and equipment selection for high-availability environments. Prepare and maintain construction drawings and specifications using AutoCAD, Revit MEP, or similar tools. Support system load calculations, energy modeling, and equipment sizing using tools like Trace 700, HAP, or eQUEST. Participate in field surveys, site investigations, and facility condition assessments. Able to perform commissioning, testing, and balancing to ensure optimal system performance. Review submittals, respond to RFIs, and support construction administration activities. Ensure all designs meet applicable codes and standards (ASHRAE, NFPA, IBC, IMC, LEED). Maintain organized documentation including technical memos, reports, and as-built drawings. Gain hands-on experience with Building Management Systems (BMS) for centralized control of HVAC, lighting, and life safety systems. Collaborate with electrical, architectural, and structural teams to deliver integrated solutions. At Leidos, we don’t want someone who "fits the mold"—we want someone who melts it down and builds something better. This is a role for the restless, the over-caffeinated, the ones who ask, “what’s next?” before the dust settles on “what’s now.” If you’re already scheming step 20 while everyone else is still debating step 2… good. You’ll fit right in.

Requirements

Ability to obtain a Top Secret/SCI with Polygraph clearance
Bachelor’s degree in Mechanical Engineering or related field
4+ years of relevant experience with a Bachelor’s, or <2 years with a Master’s
Working knowledge of static and dynamic analysis techniques
Proficiency in CAD software (e.g., SolidWorks, AutoCAD)
Understanding of design specifications, dimensioning, and documentation standards
Experience supporting prototype fabrication, testing, and feasibility studies
Strong communication skills and ability to work across multidisciplinary teams
Solid foundation in thermal analysis, hardware design, and product development
Excellent organizational skills and attention to detail

Nice To Haves

Any level of active clearance.
Active Top Secret/SCI with Polygraph.
Master’s degree in Mechanical Engineering or related discipline
Experience with SolidWorks Simulation, ANSYS, or other FEA/thermal tools
Hands-on experience in prototyping and iterative product development
Ability to contribute independently to moderately complex engineering projects
Familiarity with project management tools and principles
Knowledge of manufacturing processes and DFM best practices
Exposure to hardware design in regulated environments (e.g., aerospace, defense, medical)
Ability to apply engineering standards and best practices in documentation and design

Responsibilities

Help figure out the design and layout of HVAC systems, including ductwork, piping, ventilation, and equipment selection for high-availability environments.
Prepare and maintain construction drawings and specifications using AutoCAD, Revit MEP, or similar tools.
Support system load calculations, energy modeling, and equipment sizing using tools like Trace 700, HAP, or eQUEST.
Participate in field surveys, site investigations, and facility condition assessments.
Able to perform commissioning, testing, and balancing to ensure optimal system performance.
Review submittals, respond to RFIs, and support construction administration activities.
Ensure all designs meet applicable codes and standards (ASHRAE, NFPA, IBC, IMC, LEED).
Maintain organized documentation including technical memos, reports, and as-built drawings.
Gain hands-on experience with Building Management Systems (BMS) for centralized control of HVAC, lighting, and life safety systems.
Collaborate with electrical, architectural, and structural teams to deliver integrated solutions.