GNC – Junior GNC Engineer

At Orbital Paradigm, we design, develop, manufacture, and operate reusable orbital logistics systems. Our spacecraft perform multiple orbital mission profiles and return safely to Earth through hypersonic atmospheric reentry and landing with pinpoint accuracy for rapid refurbishment and reuse. Role Description We are looking for a Junior GNC Engineer to support the development, verification, and implementation of guidance, navigation, and control capabilities for reusable orbital logistics vehicles. The role covers mission analysis, trajectory design, guidance algorithms, navigation and estimation, control laws, flight dynamics, sensors and actuators modelling, simulation, and support to software implementation and testing. The engineer will work closely with systems, software, avionics, propulsion, aerodynamics, mechanical, and AIT teams to develop reliable GNC solutions across orbital operations, reentry, and landing. This role is suited for an early-career engineer with strong fundamentals in dynamics, control, simulation, and numerical methods, and clear motivation to work on spacecraft GNC. Key Responsibilities Support the development, validation, and improvement of GNC algorithms and simulation models. Assist with mission analysis, trajectory design, flight dynamics analysis, and performance assessments. Develop and maintain the GNC simulation infrastructure. Develop and maintain simulation models for GNC design, verification, and validation. Model spacecraft dynamics, sensors, actuators, environmental disturbances, uncertainties, and failure cases under the guidance of senior engineers. Support Monte Carlo simulation campaigns, robustness analyses, sensitivity studies, and performance verification. Assist with the development and validation of navigation and estimation algorithms, including Kalman filtering or equivalent methods. Assist with the development and validation of control laws for spacecraft mission phases. Support implementation of GNC algorithms into flight software and embedded systems. Support SIL, HIL, EGSE, and closed-loop test activities for GNC verification. Assist with the definition and documentation of GNC requirements, interfaces, validation logic, and verification evidence. Support sensor and actuator modelling, characterization, calibration, and performance assessment. Analyze simulation, test, and flight data to validate models and improve GNC performance. Prepare technical documentation, simulation reports, verification reports, and review material. Collaborate with systems, software, avionics, propulsion, aerodynamics, mechanical, and AIT teams. Required Qualifications 0–1 years of professional experience in GNC, flight dynamics, control systems, robotics, aerospace systems, or related technical fields. Degree in Aerospace Engineering, Control Engineering, Mechanical Engineering, Electrical/Electronic Engineering, Applied Mathematics, or a related technical field. Hands-on technical experience through a rocketry team, CubeSat project, robotics team, Formula Student team, equivalent engineering club, academic project, thesis, or applicable internship at a relevant aerospace company or startup. Strong fundamentals in dynamics, flight mechanics, control theory, estimation, numerical methods, and simulation. Good proficiency with MATLAB/Simulink for modelling, simulation, analysis, or algorithm development. Basic understanding of at least one of the following: Kalman filtering, nonlinear control, or spacecraft guidance. Exposure to Monte Carlo simulation, robustness analysis, uncertainty modelling, or performance verification. Basic familiarity with sensors, actuators, environmental disturbances, dynamics modelling, and system uncertainties. Basic familiarity with SIL, HIL, or closed-loop testing concepts. Ability to write clear technical documentation, analysis notes, test procedures, and verification reports. Strong problem-solving skills and willingness to work hands-on with simulation, testing, and integration activities. Ability to work effectively across multidisciplinary engineering teams. Full proficiency in English, written and spoken. Preferred Qualifications Internship experience in aerospace, robotics, automotive, control systems, simulation, or another high-performance engineering environment. Experience in a startup, student team, laboratory, or small engineering team with fast design-build-test iterations. Basic proficiency with additional programming languages such as Python, C/C++, Rust. Familiarity with aerospace industry standards such as ECSS, NASA, or MIL. Exposure to spacecraft, launch vehicles, reentry systems, orbital maneuvering, aircraft, drones, robotics, or autonomous systems. Good knowledge of orbital mechanics, atmospheric flight, reentry dynamics, precision landing, or mission analysis. Knowledge of the characteristics and working principles of GNSS, IMUs, star trackers, sun sensors, radar altimeters, reaction wheels, thrusters, or aerodynamic control surfaces. Exposure to model-based design, automatic code generation, real-time simulation, SIL, HIL, or EGSE environments. Basic knowledge of tools such as GMAT, STK, Basilisk, Modelica, or equivalent mission analysis and simulation tools. Knowledge of software development principles and tooling Good proficiency in Spanish. What We Value Excellence in technical work, execution, and professional conduct Strong ownership mindset, with the ability to drive activities to clear outcomes through accountability, proactivity, and resourcefulness Clear, efficient, direct, and constructive communication Team-first attitude with low ego and strong cross-functional collaboration What We Offer Location: Madrid, Spain (office-first) Flexible hybrid work (2 days/week from home + 2 fully remote weeks/year) 30 vacation days (23 flexible, +7 during holidays). Salary depending on experience and profile Relocation package depending on seniority and profile Flexible compensation (meal vouchers, health insurance, public transport) Company shares plan