Podcast: What Is The Future of Supersonic Travel?

After 18 years, Aerion, developer of the AS2 supersonic business jet, halted operations following loss of funding. On June 3, Boom announced an order from United Airlines for its Overture supersonic commercial airliner. With these mixed signals, where is the supersonic market heading? Join Aviation Week’s Business and Commercial Aviation editors Guy Norris, Bill Carey and Molly McMillin as they discuss its future.

Don't miss a single episode. Subscribe to Aviation Week's podcasts in iTunes, StitcherSpotify and Google Play. Please leave us a review.

Here is a rush transcript of the June 4, 2021, BCA podcast.

Molly McMillin:            Good day and welcome to our podcast by Aviation Week's Business & Commercial Aviation. I'm Molly McMillin, managing editor of business aviation. Joining me today are senior editors Guy Norris and Bill Carey. Thank you for joining us today. We're going to discuss supersonic flight. One of the most recent developments was Aerion's decision to cease operations, and most recently, United Airlines says it's placed an order with Boom for 15 supersonic airliners plus options for many more. Let's first talk about Aerion. They've ceased business after spending 18 years in development on the program. Guy, what happened?

Guy Norris:                 Well, yeah, thanks Molly. It's a good question. I mean the bottom line is they ran out of money and after such a long time, it seems like a tragedy, but as far as the industry is concerned, everybody thought Aerion and the AS2 Supersonic business jet would probably be the front runner as far as reentering the world of commercial civil supersonics. So, yeah, it was a big shocker. And I really think that if it hadn't been for this Boom announcement that you just mentioned, that people would still be questioning whether the whole supersonic thing had been derailed by this. But yeah, basically the bottom line is they were trying to extend with a new round of funding and the existing shareholders, which were going to be part of this, were reluctant to continue to invest. And that was part of the sort of the discussions, the negotiations that were involved in extending this new round of financing. So, without the buy-in of the existing investors, there was just nowhere for them to go. So, sadly it was wrapped up rather in a hurry.

Molly McMillin:            Thank you, Guy. Their decision has certainly spread through the supply chain and in Melbourne, Florida, where they were going to set up assembly. Bill, can you talk about how Aerion’s decision has reverberated into the industry?

Bill Carey:                   Yeah, sure. Their decision affected more than just Aerion itself. They had come to a number of different supplier agreements with some major aerospace, second tier and companies. Spirit AeroSystems was going to provide a few slash components. Spirit would be a first or second tier company, I would think, and was also an investor as was Boeing. Honeywell had come to an agreement with them for a Flight-Deck Avionics and a connectivity suite BAE Systems was going to design the fly by wire flight control system. Universal Avionics was going to provide it's Skyline's head wearable display, which was, I thought was an interesting development. And Collins Aerospace also was signed on as were other major suppliers. I don't know to what extent or how much in progress those supplier agreements were. I think perhaps furthest along was GE with the Affinity engine.

                                   They confirmed that they had stopped work on that program, and I think it affected on the order of 170 employees who they reassigned to other projects. So, it was more than just Aerion that was affected by this. And I think what was really kind of reflective of the late stage in development, the company had reached was the fact that it was going to build 110 acre campus, a headquarters and a production facility in Melbourne, Florida at Melbourne Orlando Airport. The airport, subsequent to this announcement, which was on May 21, issued what I thought was a rather candid statement saying they're surprised and disappointed by that decision, which caught them as well as many people in the industry by surprise. They at the airport had made available a shovel ready plot for the Aerion Park development.

                                    And according to that statement, Aerion was responsible for the vertical development construction on their parcel and Aerion Park itself was projected to employ 675 people by 2026. It had been announced with some fanfare by Gov. DeSantis back in April 2020. So, I would assume if it gets to that level, that they had reached agreement on any sort of tax incentives that were being made available to the company to build in Melbourne. So, it affected a broad swath of the industry.

Molly McMillin:            Right. And is the market still there for a business supersonic business jet?  I know United’s order was for commercial airliner, but Gulfstream has been looking at that these for a while. I think Dassault may have been ,too. But what do you think?

Guy Norris:                 Well, from my perspective, Molly, I think it's important to really say, "Okay, what was different about the Aerion design versus other potential supersonic business jets that are out there. And the key thing that really was the whole mark of that design was - it was not a low boom design. So, in other words, it would be clear to fly supersonically over the oceans, but over land, it would have to adhere to this sort of transonic phase of flight near sonic sort of thing, near supersonic. And because of that, the more Aerion looked into the design, the more it realized that roughly 75% of this business traffic requires over land flight and especially here in the US. So, they had to do something to really raise the speed of this capability over land and the design changes that they made and the complicated system that they had to invoke because of it, namely a transition away from the supersonic laminar flow control wing that they were looking at, which had been the hallmark of that design from the very start to a more of a classic delta, ogee delta.

                                   In addition to, I'm sorry, not an ogee delta. I think it was just a cranked arrow delta wing, and also the use of this boom, this cruise system, which kind of really is the thing that Bill was sort of referring to there. The work they were going to do with Honeywell and Collins on display and systems that would detect when they could do this clever trick with the atmosphere to basically fly as close as you can to the speed of sound without causing a boom on the ground, make it just a rumble. Those are very complicated things to do. So, this niche that Aerion had gotten into was getting smaller and smaller and smaller. And while there would have been the first to be the first supersonic business jet, the operational requirements and the narrowness within which they operated was beginning to be a factor.

                                   Now, if you look at, going beyond this, the generation beyond what will be really later this decade is all being proven out potentially by Lockheed Martin's, X-59 low boom demonstrator. Now as you know, the shaping of that will deliberately reduce the overpressure, which would be the cause of any sort of the sonic boom that you hear on the ground. And that design really fundamentally will not only help legislators change the narrative. And in fact, allow certain decibels of sonic boom over the land, but there will also be the pathfinders really for follow on business jet designs that people like Northrop Grumman, or certainly Gulfstream anyway, in the States. And maybe Dassault in Europe would be pursuing in future. I don't know, Bill. That's kind of my take on it.

Bill Carey:                   Yeah. And I think the Boom's operational model differs and perhaps contributed to their ongoing survival actually. And they, I think based on your reporting, Guy, the major routes they're considering are from New York, New Jersey to London and also on the West Coast from San Francisco to Asia. So, we're talking about primarily oceanic flight where they could fly at that supersonic speed. I think what they're proposing for the Overture, is it a Mach 1.7? Does that sound right?

Guy Norris:                 Yeah. And you're right, Bill. I mean, originally they, and this is the Mach 2.2 capability, but I think they've been discussing with Rolls Royce, their engine, sort of a study partner. And I think the reality is that to meet any chance of meeting Stage Five noise compliance and inefficiency targets, they have to pair that top speed back down to 1.7. So, at 1.7, you can still make this calculus work, but I think much lower than that and you kind of starting to get into the well, is it really worth it territory.

Bill Carey:                   Right.

Guy Norris:                 But certainly, from the market perspective, Boom's business case is a lot different to what Aerion is looking at. Aerion was very specifically targeting that niche market. Boom will take up to 88 passengers in a, you could be talking about a very large BBJ type cabin for business applications, but so far, it's very much commercial as United ordered 15 aircraft plus 35 options. And I think it could really take off if they can meet what are obviously some pretty severe, still technical challenges. But both of these designs were conventional Delta shaped Delta wing and are Delta wing shaped supersonic aircraft. And I think what comes beyond this maybe in the 2030s will be these new low-boom shapes, which should not be compromised by whether they over land or over sea.

Bill Carey:                   Right.

Molly McMillin:            Does Aerion’s development take the pressure off of Gulfstream and Dassault, and Bombardiar in their ultra-long range business jet? As Gulfstream said that they already have an aircraft that flies nine-tenths the speed of sound. So, that was kind of the only pressure from the top was a supersonic business jet coming to market

Bill Carey:                   The Aerion was supposed to accommodate eight to 12 passengers. So, I think that takes away the competition at that end of the market, the large cabin long range business jets.

Molly McMillin:            Right. Okay.

Guy Norris:                 And of course, we shouldn't forget, Molly, that companies like Exosonic, I think there are some other new companies out there that are looking at this space. But predominantly, most of them are again, looking at trying to make use of the more flexible low boom designs, which allow them to operate with impunity on any route that a current large cabin business jet flies.

Molly McMillin:            I think Spike is another one, right?

Guy Norris:                 Yeah, that's right. Spike. And the other thing we should probably mention is that in the States, anyway, the Air Force is sitting up and paying attention to these in a very serious way. Aerion included, had contracts from the Air Force to study executive transports and future Air Force One type applications. So, I think the fact that DOD is beginning to look at this from a, yeah, this is real perspective is another indicator that just Aerion's failure I think was tragic, I think myself, because I'd love to have seen that fly and I'm sure a lot of people would. But nonetheless, the overall trajectory is going in the right direction for the industry, I think.

Molly McMillin:            Not to put you on the spot or Bill, but do you think there could be last minute investors come on line and kind of bail them out, so to speak?

Guy Norris:                 Well, Bill, I don't know about you, but I mean, I've heard various discussions that there could be a, they were so far along that design is oven ready as it were, you just, it's ready to go. I mean, they did so much of that part of the hard work, but I think as obviously more time goes by that chance, that window narrow as it is it's getting narrower anyway. And the last I heard that they have something like 20 patents that are available now for sale and I'm sure once they start to go, then basically that's it. I don't know. Bill, what do you think?

Bill Carey:                   Well, it's curious, Aerion has gone quiet since that original and it wasn't really an announcement. It was more of an acknowledgement as far as I can tell at May 21st. I believe it was Florida Today, that was the first to report that. And then I think all of us in the media that followed up on that initial report asked Aerion if it was true and they acknowledged and issued a statement the same statement to everybody who asked and they've gone quiet since then. I haven't heard much. If you go to their website, it's still up and all the features are still available. I'd like to think that they can pull a rabbit out of their hat financially.

                                   I think Molly and Guy, both of you reported that it could have been one of their foundational investors, such as a Boeing that maybe was reluctant to put forward that last piece of capital to put them over the starting length, so to speak. And that's, we all know what Boeing's recent history has been with the 737 MAX. And then the COVID-19 pandemic has been a real, had a chilling effect on the industry.

                                   So, those are some extraordinary circumstances and I can't speak for Boeing, but I'd like to think that maybe somebody else could step forward and revive that. Their project was so far along, they were about to start cutting metals. So, I'd like to think that there's still hope out there, but I think that that hope resides on Wall Street somewhere.

Guy Norris:                 Yeah. And it's just sort of, it's ironic, isn't it. At a time when there seems to be an amazing amount of new capital coming into aerospace in non-traditional areas, such as the urban air mobility market, for example, and indeed supporting Boom, for example, where you, you're getting this a new round of input from nontraditional aerospace, sort of angel investors and these new funding mechanisms, which Wall Street seems to love right now. And yet you've got this sort of strategic, I'm using that word again, a situation for Aerion which had come so close after these so many years.

                                   And yet from what Molly and I were detecting, obviously Boeing, as you rightly say, Bill, had to step back significantly because of the pressures that it was under. It's really sort of went into semi survival mode last year through the pandemic and the MAX. And yet sort of the thing kind of tends to point back to Mr. Bass, who was the number fundamental startup for that entire vision. And I think even with his deep pockets these days, there's only so far, you're willing to go, I think at a certain point. So, very sad.

Bill Carey:                   I think the timing here is very ironic. I don't think there was any premeditation to it, but during the COVID-19 pandemic, the airlines, I think have ceded a real significant degree of their customer base of premium class travelers to private aviation charter and fractional operators. And the private aviation side of the business hopes to make that more of a permanent trend. And here we have out of the blue, Aerion folds on May 21st, and then less than two weeks later, you have United and Boom announcing an agreement for a supersonic airliner. So, and these of course would be business or premium class passengers that would fly in the Boom Overture. So, it's almost like the pendulum is gradually shifting back in favor of the airlines. It's a real strange timing that these two things happen when they did.

Molly McMillin:            Good points, Bill. And Guy, how well-funded is Boom?

Guy Norris:                 Yeah. They recently agreed to deal earlier this year with American Express and as a sort of a highlight really as a part of this general round. And they do soon, I think this is going to the, obviously the United order. It's not classified as firm per se by United, but it’s a regular deal with agreements in place and purchase provisions and that sort of thing that you would have with an Airbus or Boeing agreement. So, in other words, it's pretty solid. And as far as investors’ concerned, the next thing they'll be looking for is flight tests of the XB-1 demonstrator, which Boom has been building to really prove out the concept and show that they're a real company that can really build airplanes. So, those two signals, if they manage to keep it going, will continue to strengthen Boom's position, I think.

Molly McMillin:            Well, we're running out of time. That seems to be all we have time for today. I want to thank Bill and Guy for your time and Donna Thomas, our producer today. And most of all, I want to thank you all for listening. Thanks very much.

Bill Carey:                    Thanks Molly.

Guy Norris:                  Thank you.

Molly McMillin:            This podcast is now available for download on iTunes, Stitcher, Google Play, and Spotify.  Thank you.



Molly McMillin

Molly McMillin, a 25-year aviation journalist, is managing editor of business aviation for the Aviation Week Network and editor-in-chief of The Weekly of Business Aviation, an Aviation Week market intelligence report.

Guy Norris

Guy is a Senior Editor for Aviation Week, covering technology and propulsion. He is based in Colorado Springs.

Bill Carey

Based in Washington, D.C., Bill covers business aviation and advanced air mobility for Aviation Week Network. A former newspaper reporter, he has also covered the airline industry, military aviation, commercial space and unmanned aircraft systems. He is the author of 'Enter The Drones, The FAA and UAVs in America,' published in 2016.