The 2023 Paris Airshow was notable not only for large airframe orders but for a clear industry pivot toward hydrogen as a plausible pathway for deep decarbonisation of short and medium haul flight. Between demonstrator milestones, retrofit commitments and promotional flights, manufacturers and startups collectively signalled that hydrogen is now entering the feasibility study phase across propulsion, storage and airport operations. The next task is to convert engineering demonstrations into harmonised, regulatorily supported pilot programmes that test safety, operations and commercial viability at scale.

On the technology front, near term progress is demonstrable. The HyPERION consortium of Airbus, Safran and ArianeGroup closed a pilot project which included a proof of concept hydrogen conditioning system for an aeronautical gas turbine. That work shows the industry can adapt space and cryogenic knowhow to aircraft fuel conditioning and distribution chains - a meaningful technical step toward handling liquid hydrogen on aircraft platforms.

Meanwhile Airbus UpNext launched a HyPower demonstrator to replace an A330 APU with a hydrogen fuel cell system. That programme targets in-flight non propulsive power generated by hydrogen and is explicitly framed as a controlled way to mature integration, restartability and operability of fuel cell systems in real flight conditions. Demonstrators like HyPower are the right tactical approach; they narrow risk by isolating a subset of aircraft systems for early certification pathways while building institutional experience.

Startups and integrators are pursuing complementary routes. Universal Hydrogen completed a flight test of a hydrogen fuel cell powered regional aircraft and continues to advocate a logistics model based on modular hydrogen capsules as a way to address the chicken and egg problem between aircraft and airport fuelling. ZeroAvia used the Paris event to cement commercial relationships for its ZA600 hydrogen-electric engine and to convert MoUs into firm leasing commitments. These commercial steps - retrofit conversion studies and early anchoring of launch customers - materially raise confidence that hydrogen solutions will be trialled in real airline operations rather than remain laboratory curiosities.

Not all activity is fuel cell based. Work presented at the show included hydrogen-adapted internal combustion demonstrators for light aviation. That diversity of technical approaches - fuel cells, hydrogen combustion and hybrid architectures - is important because it widens the solution set and shortens the path to niche use cases where each approach has advantages. Being technology agnostic at the study stage reduces systemic risk.

Where feasibility studies must now focus is on the operational envelope and regulatory framework. Technically mature demonstrators do not automatically translate into safe or economical airline service. Regulatory authorities need evidence-based, harmonised certification criteria for hydrogen storage, piping and dispensers both on the ground and on aircraft. They also need standardised emergency response procedures, ground handling protocols and maintenance requirements specific to cryogenic liquid hydrogen as well as compressed gaseous hydrogen. Paris-era announcements show industry willingness to co-invest in demonstration programmes, but governments and regulators must convert demonstrator data into common certification templates and operational standards.

Airport infrastructure and supply chain are the overriding systemic constraints. A single converted aircraft or a small demonstrator fleet will not justify bespoke hydrogen production and distribution unless airports are prepared to host modular or centralized fuelling solutions that meet safety and turnaround time requirements. Feasibility studies should therefore combine aircraft integration tests with runway-to-tank gate-to-tank logistic proofs. This includes cold chain management for liquid hydrogen, safe fueling interfaces that fit existing turnaround flows, and clear assignment of liabilities among airports, handlers and fuel suppliers.

Economics will determine how fast scaled adoption happens. Several industry briefings at Paris stressed projected reductions in operating costs over time as green hydrogen production and logistics scale. Those models are sensitive to hydrogen feedstock price, capture of value from co-located industrial hydrogen demand and the amortisation period of retrofit kits or new hydrogen-capable airframes. Regulators and public funders should prioritise studies that transparently model total cost of ownership for operators under different hydrogen supply scenarios and that identify where public intervention will be necessary to bridge early market gaps.

Policy recommendations arising from the Paris follow-up are practical and immediate:

  • Sponsor airport cluster pilots that pair one or two regional operators with a hydrogen fuel supplier and a host airport. Those pilots must include safety cases, training for ground handlers, maintenance workshops and demonstrable passenger operations timelines.

  • Create a common, phased certification framework for hydrogen systems on aircraft that starts with non-propulsive demonstrations and retrofit powertrain trials, then expands to full propulsion as data supports it. Phased certification reduces risk and creates intermediate operational targets.

  • Fund interoperable fuelling interfaces and standards so that retrofit kits and new hydrogen aircraft can use the same airport infrastructure. Modular capsule concepts and standardised pump and coupling systems should be evaluated in the pilots.

  • Require public disclosure of the assumptions in hydrogen OPEX models used in preorders and MoUs so that public aid or incentives can be targeted efficiently and transparently.

  • Coordinate international bodies, led by aviation safety authorities and supported by ICAO and regional agencies, to harmonise emergency response and maintenance training requirements across key markets. Harmonisation avoids a patchwork of rules that would impede cross border operations.

Paris was not the finish line; it was the point where proof of concept became proof of potential. The demonstrators and early commercial steps presented at the show are real and informative. Feasibility work must now move from isolated technical demonstrations to integrated, regulated operational trials that prove safety, repeatability and economics. If policymakers and regulators act quickly to harmonise standards, fund airport pilots and require transparent economic modelling, hydrogen has a credible path to contribute to aviation decarbonisation on regional and eventually medium haul routes. Without that policy push, the momentum of the Paris announcements risks stalling at the infrastructure and certification bottlenecks that feasibility studies are meant to resolve.