Mechanical Engineer — Munition System

Mechanical Engineer — Munition System

Cephas Consultancy Services Private Limited San Francisco or Los Angeles Washington, California, United States

Job  :

CLI-45424-7

Job Type: Direct hire

Candidate must be comfortable completing an initial 1-month onsite training period in Kearneysville, WV, after which they will relocate back to work from either San Francisco, Los Angeles, or Washington DC.

We’re building a small, safety‑critical kinetic munition delivered by an FPV‑class airframe. The system carries an electro mechanical safe and arm device (EMSAD) governed by a seven‑state safety‑arm‑fire state machine, electromechanical safing features, and sensor suite. Everything has to survive flight loads, drops, vibration, and field handling — and fail safe at every step.

You will own the mechanical side end‑to‑end: from concept and CAD through prototypes, testing, and the transfer to production.

• Design the munition housing, internal structure, and arming mechanism (S&A train, transport pin, motor‑driven elements) in CAD.
• Define the mechanical safety architecture together with the HW and SW leads — interlocks, out‑of‑line geometry, transport‑pin retention, drop/impact behavior.
• Spec materials, finishes, tolerances, and fasteners for the operating environment (temperature, vibration, humidity, salt fog as relevant).
• Build prototypes in‑house (3D print, CNC) and run iteration loops; hand off drawings and DFM packages to external machinists / injection‑mold vendors.
• Plan and execute mechanical qualification: drop, shock, vibration, environmental, mass‑properties / CG checks, integration with the airframe.
• Own the BOM, weight budget, and CG budget. Track them like the safety‑critical numbers they are.
• Work directly alongside the HW and SW engineers — PCB outline, connector placement, harnessing, mechanism actuation requirements come out of these conversations.

• 5+ years designing mechanical assemblies that go into the field — UAV payloads, defense, automotive, aerospace, or similar regulated/rugged domains.
• Fluency in a parametric CAD tool (Solid Works, Fusion 360, Onshape, Creo, NX — pick your favorite).
• Comfort producing manufacturing‑ready drawings: GD&T, tolerance stacks, surface finishes, fits.
• Hands‑on with prototyping: FDM/SLA printers, mill, lathe, basic machining sense.
• Strong intuition for failure modes — you’ve broken things deliberately and know which question to ask next.
• Working English, written and verbal.

• Experience with safety & arming (S&A) mechanisms, fuzing, pyrotechnics, or anything else that has to be unambiguously safe before it’s allowed to be dangerous.
• Familiarity with MIL-STD-810 (environmental), MIL-STD-331 (fuze tests), or equivalent civilian standards.
• FEA / structural simulation (Ansys, Solid Works Simulation, Onshape FEA).
• Injection‑mold and metal‑casting DFM.
• FPV / small‑UAV background — payload integration, mass/CG sensitivity.

Small team, short cycles, weekly hardware iterations. You’ll have a desk next to the HW and SW engineers and a lab with prototyping kit. We expect you to be opinionated, to design for testability from day one, and to push back when the constraints do not make engineering sense.