Job Description

Purpose of the Role

You own aircraft mass and centre of gravity as controlled programme quantities. Weight growth is the classic failure mode of an eVTOL programme: the aircraft closes on paper, then gains mass through detailed design until range, payload or hover margin is gone. This role exists so that mass has an owner whose only job is to protect it.

This is deliberately a cross-domain role reporting to aircraft-level authority rather than sitting inside a domain, because every domain has an incentive to spend mass and none has an incentive to defend the total.

Role Boundaries

You own the mass and centre of gravity budget, its allocation to domains, and the reporting and control process. You do not design anything, and you do not own the aircraft energy closure, which sits with Principal Aircraft Conceptual Design and MDAO, or the substantiated performance evidence, which sits with Principal Vehicle Performance. Where those roles need mass inputs they take them from you, and where a domain exceeds its allocation you report it rather than absorbing it.

Key Responsibilities

• Own the aircraft mass and centre of gravity budget: allocation to domains and configuration items, growth allowance, margin policy and the definition of what is included at each maturity level.
• Own mass properties reporting: a controlled, auditable mass statement at agreed intervals, with the basis of every entry stated as calculated, estimated or weighed.
• Own centre of gravity control across loading cases, including EMS mission variants, patient and equipment loading and battery installation.
• Own the mass growth control process: threshold and trend monitoring, exceedance escalation and the mass review forum.
• Provide mass inputs to the aircraft closure, to performance substantiation and to structural loads, with consistent assumptions across all three.
• Own weighing programme definition for prototype and production aircraft, and the correlation between predicted and weighed mass.
• Support trade studies with credible mass sensitivity, and challenge domain mass claims on the merits.
• Report mass status to the programme honestly, including when the trend is adverse and its consequence for range, payload or hover margin.

Required Experience: Must Have

• 10+ years in mass properties, structures or aircraft performance engineering, including at least four owning or maintaining an aircraft mass and centre of gravity budget.
• Personal ownership of a controlled mass statement on a development aircraft programme, through at least one major design maturity gate.
• Mass growth control in practice: allocation, monitoring, exceedance handling and the organisational discipline it requires.
• Centre of gravity control across loading and mission variants.
• Weighing programme experience and correlation of predicted against measured mass.
• Credible experience defending a budget against cross-domain pressure.

Required Experience: Preferred

• eVTOL or electric aircraft, where mass sensitivity is amplified by battery energy density.
• Mass properties within a digital mock-up or PLM environment with automated mass roll-up.
• Mission or role-equipment variant mass management.
• Structural weight estimation methods and their validation.