Thriving under the radar, the supersonic jet industry expands

In a significant stride towards faster, more efficient travel, Spike Aerospace, based in Massachusetts/Boston, is developing the S-512 Diplomat, a low-boom business jet aimed at revolutionising the global business aviation market.

The S-512, with its focus on geometry and advanced design features, seeks to address community concerns over noise and environmental impact. The design includes a long nose, high sweep, custom tail volume, and multi-lobe lift distribution, all aimed at reducing shock coalescence and controlling a shockwave, a complex task similar to conducting music at high speeds.

Early customers are willing to accept higher operating costs for faster schedules and more privacy, as the S-512 promises to deliver a speed of around Mach 1.6, reducing noise to a soft thump. The design and placement of the engines, quiet turbofan engines shielded from other parts, further contribute to the reduction in noise.

Spike Aerospace is engaging with highly experienced professionals from top aerospace companies and academic partners as it refines the design and certification roadmap. The company is not discussing some topics, such as active cancellation systems, specific efficiency tradeoffs between low-boom shaping and cruise, and composite tailoring for thermal expansion, but is focusing on advanced computer modeling, precise shaping of noise, durable materials, and engines that don't use afterburners.

If the FAA and ICAO create overland noise rules, a quiet supersonic jet, especially a business jet, could be an important achievement for US aerospace leadership. The development process of the S-512 uses computer simulations to improve design and wind tunnel tests to tackle specific issues. If manufacturing focuses on digital processes and out-of-autoclave composite methods, ongoing costs can be managed even at lower production volumes for the S-512.

The FAA's authority to set and enforce noise standards is longstanding; supersonic-specific operational rules will determine how quiet-SSTs can fly profitable overland schedules. If the S-512 meets the low-boom rule and the Stage 5 airplane noise standards, it can fly nonstop on time-sensitive routes, including city pairs like New York to London in under 4 hours.

Airlines also need to balance potential profits with increasing fuel costs. The S-512's lower-mass, lower-seat platform lowers the money at risk during certification. However, fuel economy is still a tough challenge for the S-512, as supersonic flight has a lower lift-to-drag ratio than subsonic flight, meaning it uses more fuel for each passenger mile.

Spike's brand refresh highlights a cabin designed for privacy and productivity, targeting executives, heads of state, and urgent missions. Time reliability is important for this group, and the S-512's faster schedules and focus on reducing noise make it an attractive option.

The S-512 is uniquely positioned to meet the demand for faster, more efficient travel in the global business aviation market. If manufacturing focuses on digital processes and out-of-autoclave composite methods, ongoing costs can be managed even at lower production volumes for the S-512. A quiet thump over the Hudson River could mean more than just a plane flying by; it could signal that the US is regaining its speed advantage. Spike's spokesperson said, "An acceptable PLdB will need to be determined and certified."