FULLY UPDATED – Boom Supersonic has radically redesigned the Overture passenger aircraft. From the Concorde look-a-like that was unveiled in late 2016/early 2017, Overture has now changed the overall aerodynamic concept. The new design has been unveiled at a press conference at the Farnborough Airshow on Tuesday.
The original 65-88 seater Overture had a delta wing very similar to that of Concorde, with a needle-shaped nose and no tailplane. Two engines were positioned under each wing, with a third one in the tailplane.
Boom has thrown that concept out of the window on the new Overture. In fact, the new version in a way resembles the Boeing XB-47 Stratojet that was designed in 1947 and later evolved into the Boeing Dash 8. For example, the new Overture no longer has a full delta wing, but a swept and contoured, high-aspect ratio, gull-wing with ‘blunt’ wing tips. The wing is twenty percent more efficient than the previous design.
The new version of the Overture, with four engines under gull wings, and a separate horizontal tailplane. (Boom Supersonic)
The wing morphs gently into the fuselage, which has smaller and squarer windows. There is a horizontal tailplane at the back, not dissimilar to that on a Phantom fighter aircraft. The vertical fin is much smaller. The cockpit is positioned in a slightly higher position compared to the cabin. There is no longer an engine at the back of the fuselage. The new version is designed using the aerodynamic principles of area ruling, in which the cross-section varies along the length of the aircraft. “This means we have made the fuselage a bit bigger at the front and a little bit skinnier at the back. This will not only lead to more aerodynamic efficiency but also to a better passenger experience”, said Blake Scholl.
This is the original version of the Overture with United livery. (Boom Supersonic)
The original Overture was 62 meters/205 feet long, this has been slightly reduced to 201 feet. The wingspan was 18 meters/60 feet but is now 32.3 meters/106 feet. The range of 7.870 kilometers/4.250-4.888 nautical miles is still 4.250nm. Maximum altitude and speed are unchanged at 60.000 feet and Mach 1.7. No new Maximum Take-Off Weight has been given, but it was 77.111 kilograms/170.000 pounds.
Why a redesign?
On the reasons for the redesign, Blake Scholl says: “The design that you have seen and love is actually over five years old. Since then, we have done more than 26 million core hours of simulation, iterated to over fifty design cycles, and confirmed our design with five wind tunnel tests. (…) There wasn’t something wrong with the original Overture, but we learned so much over the years that we wanted to improve the configuration on speed, safety, and sustainability.”
Scholl said that Boom will make an announcement on the propulsion later, having a partnership with Rolls-Royce for some years. “We have made a lot more progress on propulsion than we are sharing today. The engine design has come along quite well, we are looking at multiple options that are relatively straightforward to adapt for supersonic flight.” Whatever the engine will be, it will have a higher by-pass ratio for more efficient and quieter operations at high and low altitudes. As before, the Overture will have no afterburners to push it over Mach 1, unless Concorde. “To fly supersonically, we don’t need afterburners. We don’t like the afterburners.” From day 1, the aircraft/engines will be certified for 100 percent sustainable aviation fuels (SAF).
Top view of the Overture, which shows the contoured fuselage that is wider at the front and thinner at the back. (Boom Supersonic)
The improved aerodynamics and higher by-pass ratio engines are two improvements for quiet operations. The third is a software one: “Overture is the first aircraft with a software-optimized take-off, with flaps and slat settings, engine settings, climb, all optimized to minimize noise on the ground.” To improve safety, the engines have been moved back further after to have the passenger cabin out of the so-called rotor burst zone, in which an uncontained engine failure could result in engine parts puncturing the fuselage.
Boom sticks to 2026 first flight
Despite running behind schedule with test-flying the XB-1 demonstrator and doing the radical redesign, Scholl and Boom sticks to an optimistic schedule. That includes the groundbreaking of the factory in Greensboro (North Carolina) this year, production start of the Overture in 2024, roll-out in 2025, first flight in 2026, and entry into service in 2029.
That gets the skeptics to continue to question whether the Overture will get ever off the drawing board, but Scholl countered that by announcing a few new partnerships for the program. It has got Collins Aerospace on board for advanced systems like nacelles, the ice protection system, and overall aircraft performance. Eaton will develop the fuel distribution, measurement, and inerting systems. Finally, Scholl announced Safran Landing Systems as the partner to design the landing gear, but the partnership with the French company could expand to further systems. More announcements on the flight control systems and propulsion will follow in the coming months.
Boom and Northrop Grumman will explore a special mission version of Overture. (Northrop Grumman)
Boom Supersonic also announced a strategic partnering agreement with Northrop Grumman to develop special mission versions of the Overture for defense and government purposes, like the transportation of troops and cargo, rapid response, or surveillance. Boom will tap into the experience of Northrop Grumman and explore options, but these versions will not become available until after five years after the introduction of the civil version of Overture. The initiative is unrelated to the Strategic Funding Increase (STRATFI) funding by the US Air Force that was announced in January and which could lead to the US Air Force acquiring the Overture, potentially for an Air Force 1 kind of role.
One reporter asked Scholl to respond to a Tweet, in which Boom is accused of being the “Theranos of aviation”, the US healthcare company that was touted as a breakthrough company but never got beyond the planning stage. After a five-second pause for thought, Scholl replied: “I can’t wait to see everybody on board. The proof is in the pudding, but I am incredibly proud of my team and my suppliers. There will always be doubters.”
Active as a journalist since 1987, with a background in newspapers, magazines, and a regional news station, Richard has been covering commercial aviation on a freelance basis since late 2016.
In 2022, he has gone full-time freelance. Richard has been contributing to AirInsight since December 2018. He is also writing for Airliner World and Aviation News. From January 2023, he will add a part-time role with Dutch website and magazine Luchtvaartnieuws. Twitter: @rschuur_aero.