However, differences in shippers’ willingness to pay for greener logistics mean that broader industry coordination, policy support and scaled-up SAF supply will be critical to ensure that cargo market resilience aligns with aviation’s climate objectives. During 2026, air cargo demand is expected to grow by around 2.6%, with volumes reaching 71.6 million tonnes and revenues of approximately $158 billion. Yields are forecast to remain broadly stable and still well above pre-pandemic levels, reflecting the sector’s continued role in moving high-value, time- sensitive goods. Factors affecting passenger and cargo outcomes Across both passenger and cargo markets, geopolitical tensions, trade policy fragmentation, economic volatility and capacity constraints, stemming from aircraft delivery delays, supply chain bottlenecks and shifts in airline capacity deployment are expected to remain defining features of the aviation operating environment. These factors continue to shape traffic outcomes unevenly across regions and market segments, influencing risk profiles, investment horizons and network strategies. While they introduce greater uncertainty into short- and medium-term planning, they do not undermine the long-term growth outlook. Instead, they reinforce the importance of resilience planning, flexible capacity strategies and diversified traffic portfolios as airports and airlines navigate growth alongside decarbonization objectives. Executives predicted that an emerging area for collaboration and discussion in 2026 will be the development of interconnected airport-port fuel infrastructure. Aircraft and engine manufacturing constraints continued to affect fleet renewal in 2025 and airlines’ ability to cope with increasing demand. While production performance at major original equipment manufacturers (OEMs) showed signs of stabilization, bottlenecks across engines, components and supplier capacity continued to slow down new aircraft deployment and slow progress towards decarbonization. In 2025, Airbus delivered just under 800 commercial aircraft, meeting its revised annual target, while Boeing recorded 600 deliveries,142 its highest level since 2018. In terms of gross orders, Boeing recorded 1,175, enough to surpass Airbus (1,000) for the year (see Figure 5). These improvements marked an important step forward, yet both manufacturers acknowledged that output remained constrained by supply-chain fragilities, quality controls and workforce challenges. COMAC, China’s state-owned aircraft manufacturer, has collected 1,000 orders to date,143 mostly from China Eastern, Air China and China Southern Airlines. During 2025, the company also faced supply-chain bottlenecks, exacerbated by reliance on foreign-sourced engines. Nevertheless, the manufacturer’s large order book and state support underscore its potential to gradually increase production and begin carving out a niche in regional markets. Engine availability emerged as the most important bottleneck, with sustainability implications extending well beyond production lines. Shortages of engines and spare parts led to delivery delays, aircraft groundings and operational disruptions,146 highlighting a severe imbalance between airframe production and engine readiness. Similar pressures were reported for some carriers that had to retire very young aircraft to use parts for other fleets.147 These disruptions have had direct consequences for emissions reduction efforts. Delays in introducing new-generation aircraft have forced airlines to keep older, less fuel-efficient planes in service for longer, increasing fuel use, maintenance costs and emissions. At the same time, industry analysts and aircraft lessors highlight growing inefficiencies in capital use, as airlines are paying for aircraft they cannot fully deploy. During 2025, supply chain challenges extended beyond engines to avionics, fuselage sections and interiors, further constraining production ramp-ups. The continued mismatch between aircraft demand and manufacturing throughput has reinforced near- term sustainability risks. At the same time, investment in future aerospace technologies accelerated. Japan’s one trillion-yen aerospace strategy fund aims to support next- generation propulsion, hydrogen technologies and advanced manufacturing,148 while experimental programmes (e.g. Boom Supersonic’s XB-1 demonstrator, which broke the sound barrier using SAF-compatible design principles)149 highlight longer-term innovation pathways. However, these initiatives are unlikely to ease manufacturing bottlenecks in the near term. At the same time, although supersonic flight is gaining interest among some US airlines150 (with Boom Supersonic holding up to 130 optional orders), many commentators have raised concerns about the potential fuel consumption. These concerns centre on the sustainability of supersonic operations and the risk that they could further strain already limited supplies of SAF.4.2 Aircraft and engine manufacturing bottlenecks Global Aviation Sustainability Outlook 2026 35