Senior Mechanical Engineer - Stress Analysis

Zipline • South San Francisco, CA

12d • Onsite

About The Position

Zipline is the world’s largest and most experienced drone delivery service, aiming to serve all humans equally by providing access to essential goods. They design, build, and operate an autonomous logistics system, making deliveries globally. The company is seeking practical problem solvers who thrive on real-world challenges and rapid growth, motivated by building systems with a meaningful impact. This role involves owning aircraft structural analysis, system-level Global Finite Element Models (GFEMs), and assembly-level Detailed Finite Element Models (DFEMs). The engineer will apply first-principles analysis and design-test-analysis loops to ensure aircraft safety, lightness, and availability for continuous logistics operations. The work directly impacts aircraft airworthiness, fleet uptime, mission success, vehicle life, maintenance intervals, failure root-causing, and payload/range capabilities. The position reports to the Structural Analysis Lead and collaborates across design, test, reliability, systems, and field operations. The role is based in South San Francisco, with travel typically 5-10%. The ideal candidate is hands-on, uses analysis to drive design, excels in a fast-paced environment, and is excited to solve complex problems with simple, elegant solutions.

Requirements

• Minimum 5 years of experience in structural analysis for aircraft or complex aerospace vehicles working with metallic, composite, and polymer structures.
• Hands-on hardware experience.
• Demonstrated ownership of a top-level GFEM or equivalent system-level model integrating multiple subsystem inputs.
• Experience managing contributions from 3–5 engineers.
• Deep capability with industry-standard tools (e.g., NX, FEMAP/NX Nastran, ANSYS, Siemens Design Center).
• Proficiency scripting in Python or MATLAB to automate workflows and reports.
• Solid classical stress and dynamics background, including Roark/Bruhn-level hand-calculation fluency plus structural modes, random vibration, and forced-harmonic analysis experience.
• Proven track record of experimental correlation: defining instrumentation, producing pre-test predictions, and tuning models to match static/dynamic/flight tests within engineering tolerances.
• Clear owner mentality with rapid decision cadence.
• Tolerance for ambiguity and shifting configurations.
• Disciplined documentation habits.
• Ability to identify opportunities to maximize impacts to cost, scalability, and fleet health.
• Must be eligible to work in the US.

Nice To Haves

• You’ve built your own prototypes to get quick answers.
• Pencil and paper calculations are always your first step.
• You prefer simple and fast over detailed and large.
• You are on the floor during system testing.
• You have never presented a FEM plot without adjusting the legend scale.

Responsibilities

• Own and maintain the top-level Global Finite Element Model (GFEM), setting and enforcing standards for material properties, numbering, interfaces, model fidelity, and validation procedures.
• Produce rapid analysis studies and design guidance, performing hand calculations and creating lightweight beam/shell FEMs to drive design trades, delivering updated models and results within 24–48 hours.
• Perform structural sizing and certification support, including static, dynamic, stability, and damage-tolerance analyses for metallic and composite structures; evaluate and optimize systems for structural loads, vibration modes, and deflections; produce documented margin and load reports.
• Plan and correlate tests by defining pre-test predictions, instrumentation plans, and post-test correlation workflows; tune models to test data to drive model agreement within target tolerance.
• Lead root-cause investigations for test and field failures, generate corrective design changes, and work with relevant teams to close actions and update inspection criteria.
• Collaborate daily with design, systems, reliability, test, and flight operations; create and document standardized in-house FEM tools, verification checklists, and model-release processes; mentor 3–5 contributors to the GFEM.
• Support flight-test campaigns and field remediation events on-site, execute rapid test fixes, and prioritize fleet-impacting issues to minimize downtime and preserve flight schedules.
• Resolve test issues and provide corrective action direction for issues found in qualification testing.

What This Job Offers

• Job Type: Full-time
• Career Level: Senior
• Education Level: No Education Listed