Mechanical Integration and Test Engineer

HyLight; Paris; On-site; EUR 52,000 - 68,000; Full time

Benefits offered by this job

Public transport reimbursement

Bike provided

Free lunch

Bi-annual offsite trips

International team

Offices on a former airbase

Job summary

HyLight seeks a Mechanical Integration and Test Engineer to own the drone’s mechanical lifecycle from design through flight. You will bridge engineering perfection with operational reality, ensuring robust assemblies and rapid iteration for mission-critical inspections.

Based in Paris, you will lead design for assembly, fatigue analysis, HALT/HASS tests, and root-cause investigations while collaborating with the Mech Team and on-site operations during tests and flights.

Qualifications

• Mechanical engineering degree or equivalent practical experience.
• Experience in designing rugged outdoor mechanical systems and test planning (DoE).
• Experience writing test reports and new test specifications.

Responsibilities

• Lead conceptual design of mechanical subsystems and airframe evolutions.
• Establish fatigue models and design accelerated life tests (HALT/HASS).
• Implement Root Cause Analysis and close loops between engineering and operations.

Skills

CAD

DFM

Reliability data

Python

3D printing

Welding

Machining

Sheet metal

5 Whys

Ishikawa

Education

Mechanical Engineering degree or equivalent practical experience

Tools

Test fixtures

Testing equipment

DoE

Job description

Power lines, gas pipelines and railways are still inspected the way they were 50 years ago: by helicopter. Expensive, noisy, and up to a tonne of CO₂ per flight hour.

We built the alternative. The HyLighter is a 12-metre autonomous airship running on hydrogen. It flies for up to 10 hours, almost silently, and spots a 1 mm defect from 25 metres up.

It’s not a prototype. HyLighters already fly missions for France’s largest energy and rail operators and have flown over the Palace of Versailles. Backed by Y Combinator, we just raised €13M to go from 4 airships to 15.

Working at HyLight

We design, build and fly every HyLighter ourselves, under one roof on a former airbase. Which means:

• You own it all the way. At a big company, you’d own a small piece of one subsystem. Here, you design it, test it, stand on the airfield when it flies, and see the client act on the data it brings back.
• Weeks, not years. Ideas go from whiteboard to flight test in weeks.
• Responsibility from day one.

Job Summary:

As a Mechanical Integration and Test Engineer, you will be the technical owner of the drone’s mechanical lifecycle. You will bridge the gap between "engineering perfection" and operational reality, ensuring our drones are robust, easy to assemble, and available for mission-critical inspections.

The Mission:

In collaboration with the Mech Team, your responsibilities will focus on Reliability, Industrialization, and Continuous Improvement:

• Creative Design: Lead the conceptual design of new mechanical subsystems and airframe evolutions. You will transform innovative ideas/prototypes into functional products through rapid iteration (CAD, 3D printing, machining), balancing sleek aesthetics, design for manufacturing with high-performance engineering.
• Reliability & Lifecycle Management: Establish fatigue models and design accelerated life tests (HALT/HASS) to predict component "End of Life" and maximize fleet availability. You will robustify the drone design to ensure reliable operation in challenging conditions.
• Root Cause Excellence: Implement a systematic Root Cause Analysis process for every field failure, ensuring rapid design updates and maintaining a strong feedback loop between engineering and operations.

Profile Sought:

• Background: Mechanical Engineering degree or equivalent practical experience.
• 3+ years experience in designing resistant outdoor/rugged mechanical systems (material fatigue, vibration). Experience in test planning (DoE), designing test equipment (fixtures, set-ups), actual testing, analyzing results, and writing reports as well as new test specifications.
• Mindset: You possess a "Shop Floor" mindset, you enjoy spending time in workshops and do not consider work finished until the physical product is validated, not just the CAD file sent.

Technical Skills:

• Core Mechanics: solid CAD & DFM expertise (Design for Assembly, reduced part count), Material Mechanics (S-N curves/Wöhler, UV aging, creep, stress cycles).
• Reliability Data: Comfortable with statistical methods for reliability and data-driven approaches (Python).
• Manufacturing: Comfortable with processes such as 3D printing, welding, machining, or sheet metal work.
• Analysis Methods: Mastery of problem-solving methods like 5 Whys, Ishikawa to trace field failures to root causes.

Soft Skills:

• Highly organized and detail-oriented in documentation and execution
• Entrepreneurship: Willingness to find shortcuts and ways to do things efficiently.
• You enjoy getting your hands dirty and respect the insights of the technical team.
• Willingness to be present on-site and support operational teams during test and flight activities
• Curious, analytical, eager to learn, and proactive in problem-solving
• Good communication skills and collaborative mindset

Languages:

• French AND English: Fluent (Required)

What We Offer:

• 100% reimbursement of public transport pass (Navigo) or €800/year for sustainable commuting
• Bike provided for commuting
• Free lunch
• Bi-annual offsite trips with the whole team
• Excellent work environment: international team, team events, beautiful offices on a former airbase

Why You Should Join:

• Founder Mentality: We value extreme ownership and want people who think like founders—fast decision makers, natural problem solvers, and executers.
• Ground Floor Opportunity: You’ll be helping to shape and grow a revolutionary company with the resources to back it.
• Impact & Speed: Work in a fast-paced environment where your contributions will have immediate, tangible effects on the company’s success.