Commercial airliner development programs are focusing on early-stage R&D for environmentally-friendly aircraft. Boeing's X-66 program is progressing alongside ongoing flight testing campaigns. Airbus is leading in hydrogen research through its ZEROe program, exploring hydrogen combustion and fuel cell engines for future aircraft. Airbus achieved milestones in the A321XLR and A330-900neo programs, enhancing operational capabilities. The RACER compound helicopter by Airbus showcased its high-speed capabilities and innovative design in successful flight tests, combining helicopter and fixed-wing aircraft characteristics for improved efficiency.