Podcast: 10 Minutes About the United-Boom SST agreement

June 8, 2021, © Leeham News: United Airlines and the start-up company, Boom, last week announced an agreement by which UAL will acquire up to 50 Boom Overture SSTs.

There are some conditions Boom must meet before United will accept any airplanes. Furthermore, Boom must raise a lot of money to complete development.

In today’s episode of 10 Minutes About, LNA discusses the commercial agreement and just a few of the issues facing development of the Overture.

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59 Comments on “Podcast: 10 Minutes About the United-Boom SST agreement

  1. There alway some billionaire visionairs who want to boost their ego having such a program behind their name. But now millions need to turn into billions and authorities take a closer look most of the fun is gone.

    Flying eastbound a bed for half the price is maybe better than arriving when everybody is asleep.

    • I thought Bjorn was too kind on impossible reality to say it will work at all on the tech end.

      In my world we called it when Pigs fly. Just not happening.

  2. USAF has rediected funding to Exosonic, Boom Supersonic and Hermeus for “advanced high speed transport scale aircraft”.

  3. The podcast is generous in its assessment. This entire endeavor is laughable. In July 2020 Boom announced “an engagement agreement to explore the pairing of a Rolls-Royce propulsion system with Boom’s flagship supersonic passenger aircraft, Overture”. Meanwhile rollout of the Overture is scheduled for 2025, with the engine bays no doubt filled with Rolls-Royce Powerpoint slides. RR, which has spent 10 years and a billion dollars trying to fix the Trent 1000’s many ills, has neither the time nor the money to pull this off. No engine, no airplane. But I’m guessing no airplane, regardless. Oh, and we decided to cut the cruise speed from M2.2 to 1.7. Just a minor detail…

    The only questions are 1) when will Boom go the way of Aerion, and 2) what the hell is United Airlines up to?

      • Agreed that is a pretty weird conflict of being Green.

        Fast and high fuel use is green how?

        Not the first time a Corporation has done the spin obvious but usually it has something to do with paying execs huge sums for huge losses.

        Definitely a Hunh?

      • Cheap publicity is my guess. You can always make conditional contract that will have United spend exactly nothing unless a miracle happens and Boom delivers a working plane.

        • NEW: “Diminish your own Corporation’s credibility- for FREE!”

  4. Appears the environmental challenges could be the biggest hurdle. Maybe this type of herculaian effort should be directed at the hydrogen / electric / sustainable programs than at getting the hotshots across The Pond three hours quicker. Long term though it could be interesting. It reminds a little about the 747 vs. the Concord discussion. Essentially, 30 years from now, air travel could be quite different.

  5. The podcast points out various flaws in the Boom program. Through his series on SST, Bjorn has laid out a compelling case for the need to have an engine that can satisfy the noise regulations during TO. Without reducing the Specific Thrust during TO to around 300 m/s, it is impossible to get the plane certificated. It requires a variable cycle engine that does not yet exist in the civilian domain, although GE has successfully tested such an engine for military applications:


    Even if GE were to develop such an engine for Boom, question remains about the economic viability. How much is one willing to pay to say, shave off a few hours from a transatlantic flight? Concorde flying at Mach 2 , which means its cruise speed was 2.3 times that of a Mach 0.85 airliner, could cut down the transit time in half. That did not make the business case. Granted the fuel consumption could be brought down by a newer design, there is not that much improvement that can be made in both aerodynamics and engines. The airframe and Olympus engines of Concorde were really very good, even by today’s standards. Now cut the cruise Mach number down substantially from Concorde’s Mach 2 (Aerion was 1.4, Boom is now 1.7) to make the aircraft certificatable, the saving in transit time also comes down substantially. But that does not mean the travel time comes down proportionately, given the need to get to the airports and wait for checkin, baggages etc. So the saving in travel time may not come down much.

    So the question is:
    Forget environmental and certification issues for the moment. Can a business case be made for shaving off a small amount of travel time at the expense of a substantially higher ticket price?

    Recall COVID19 demonstrated that routine business, including international, can be done via Zoom. Not optimal, but feasible. Given that, why would business travelers flock to Boom?

    • Kant:

      Great summery. Can’t even pass your first hurdle let alone the next ones.

      Only adder is P&W got back into the game of the Adaptive engine as well.

      Either one though is a military engine that is big bucks and complexity which for the military can be (ahem) justified but for a Civie job?

      It seems that aviation always has to have that Unicorn out there. Intelligent people (more or less) getting caught up in it though is baffling.

      the only one I ever though might get someplace is a business jet type but even then the costs alone you list to start with let alone the other hurdles says no.

      • Indeed. The advanatge of the large cabin specially designed business jets like the Gulfstreams, Global express etc is that they are faster than the equivalent airliner based business jet .
        The advantage for the very rich and coprorate types in their own jet is they can work on board and often bring staff members with them. Its all done in privacy with the boarding and arrival times to match their itinerary and any delays, and then can leave for any other destination they chose. A supersonic plane is still a commercially scheduled plane through ordinary airport terminals ( and all that entails) just that its faster.

        • Duke:

          The speed advantage of the Bis Jets (or the big 3) is a marketing hype the same as Chip speed was a while back. I believe there are range impacts as well as engine wear out.

          What is relevant is what you listed after as well as in some cases closer to their final destination or a more accessible than the large airports.

          Somewhere in there for the simply rich is the cachet of it all.

          • For long range it is an advantage , although you can chose fuel efficency or time cruise speeds.
            Airbus new Two-twenty BJ based on the A220 will be larger but similar price to the top end Gulfstreams and Dassaults etc but for 12 hr plus flights the time differences will show.
            The advantages of the 747 higher speed over the newer twins also showed in flight times, but 747 is almost gone now

          • Duke:

            Yes it shows but how much? 5 minutes, 10, 30?

            But how much do you spend getting baggage off, customs (if any) to transportation and you don’t (usually) land in front of your destination door.

            So you still have travel. Save 30 minutes and get into a traffic jam!

            Like Chip speed was, they have finally back off and worked to overall processing speed with parallel processes (been a while but last I saw were 4 getting common). The point is the speed hit a bottle neck was was meaningless.

            And while not remotely an expert I seem to recall a lot of those 12 hour flights with a full load could not go max speed due to the tradeoff in not enough fuel.

        • the advantage of bizjets is more in the fact that you drive right up to the plane at a nearby small airport 5 minutes before takeoff, skip all the security theater, fly to a small airport close to your destination, walk 50 feet to the limo and drive away, cutting 2-3 hours of in airport lost time (assuming you would have checked bags) and a significant fraction of your ground transport time off the trip, as well as not having to associate with plebes or wait for the stewardess to finish fighting with the anti-masker in the back to get your 18 yr old single malt.

          actual airspeed of the bizjet is just a talking point on a slide deck to brag about.

  6. If you have a skilled specialist surgeon or a technical expert that can solve a problem to get a plant running again, or get an MRI going again, you’ll want to put him or her on an SST. This will be very useful & popular. We are now in a global market place. The advantages to business class travelers, their companies and customers are just huge.

    • William:

      I think you are a prime candidate for Boom marketing.

      Having worked in a critical plant op, you get on the horn and you call. And its not like someone walks in, says, ahhah, you need to turn it on and its resolved in seconds.

      Having spent vast amounts of time tracking those problems down, its day, weeks and sometimes months (patches get put in to get through).

      Skilled specialist surgeons spend weeks working up to a surgery, its not a time critical function, other surgeries do the stabilization. And yes I personally know of two just like that.

      In short, the time to travel from point A to point B is one tree in the forest, there are all those other trees involved in the traverse to the other side.

      • Surgeons almost never travel like you say to do highly skilled one offs that arent planned well in advance. More local flights that are say 1-2 hrs yes. Often the hardest part of any critical surgery is whether to operate at all. The major cities that these planes would fly to would often have the best around anyway. Flying to junkets on the Drug companies dime, that market is huge !

      • Yes, I’m a prime candidate for Boom Marketing and I’m proud of that.

        I frequently catch a QANTAS A330 business class Sydney to Manilla. The capsule type seats must occupy the space and weight of 4.5 Economy seats and must produce a fuel burn per passenger at that ratio as well, that’s what’s needed to get a passenger to their destination fresh. It’s just over 8 hours flight, the flight attendants are great and full of fun bon mots, quips and repartee, the food is good, the wine out of this world but I’d trade it for a more modest business class seat in Overture (about twice an economy class seat) any day to save that time and get that fresher arrival and more less time away from family and friends. Eighteen hour flights to Saudi Arabia were a killer in the context of a 12 hour x 30 day work schedule and again an SST could have cut that back.

        • William:

          Nothing wrong with being enthusiast about something and I apologize for being snarky, I should have put it better.

          But coming up with a stretch on facts shoots down the contention and in reality is a one off (no disagreement, enough one offs and you may have a business)

          Question is, could you pay for a SST BJ seat (or your company).

          • There is no problem between us. I wouldn’t pay for a business class or SST seat myself unless there was a dire situation (family sick). If flying economy I prefer to leave mid morning on a flight so as not to sleep on the aircraft, then break my journey by over night sleep in a hotel in say Singapore, Dubai or Johannesburg in a proper bed in an air side hotel before continuing the next leg of my journey. In the context of work, with no time for over coming jet lag and the health effects of poor circulation and lack of sleep in an economy class seat followed by heavy work 12 hour x 28 day work schedule I found economy class murder to my health and productivity, never seeming to get over jet lag for a week whereas more senior colleagues who had business class arrived fresh and ready for work. It was a marked difference and I wanted to give it away hence my employer now sends me business on longer trips. I’m in Australia so a 22 hour flight to get to Europe or the Americas or somewhere near Sth Africa is not unusual.

            As far as Boom Overture goes their argument that a sort of super premium economy class seat on Overture provides the same level of comfort (in consideration of shorter journey times) as a lie flat business seat seems sound as does their argument that this provides about the same per seat fuel burn.

            In terms of environment the situation is totally hopeless unless irrespecrtive of whether boom exists or not unless there is a significant increase in PtL type SAF fuel produced. Why worry about Overture?

            My own opinion is that we need a massive investment in nuclear energy. Failing this one positive aspect of PtL type fuels is that they are readily exportable. Hence the Western Australian State Government is preparing along with investors and several neighbouring countries such as Japan plans for 200GW (about 200 large power stations) of electrical energy production from wind and solar of which 90% will be exported as hydrogen, ammonia or carbon neutral fuels. Other parts of the world will be similarly fortunate in wind and solar.

      • Maybe that one commenter changed its name and putative job. No, “Boom™ boom” is not gonna fly.


    • > The advantages to business class travelers, their companies and customers are just huge <

      Not seeing them, even if the thing and its needed other structures were somehow created.

      Will be observing the future course of United/"Boom™" with real interest..


  7. Here’s my conspiracy theorist’s take.

    Boom needs fund thus a credible customer is required to raise capital.
    Boom arranges a fake deal with friends at United.
    Boom raises fund and share the cash with friends at United.
    Boom closes in three years and investors lose their money.

  8. > Boom closes in three years and investors lose their money <

    it's keystroke-mcMunny anyway, and we (all of us) have bigger issues to deal with soon enough (like, now).

    if United n' '"Boom" want to talk distracting nonsense it's fine with me; i'll be looking for the part that's not being talked about, myself..

    • “Results from a modeling analysis suggest that these aircraft are unlikely to comply with existing standards for subsonic aircraft. The most likely configuration of a representative SST was estimated to exceed limits for nitrogen oxides and carbon dioxide (CO2) by 40% and 70%, respectively. A noise assessment concludes that emerging SSTs are likely to fail current (2018) and perhaps historical (2006) landing and takeoff noise standards.

      On average, the modeled SST was estimated to burn 5 to 7 times as much fuel per passenger as subsonic aircraft on representative routes. Results varied by seating class, configuration, and route. In the best-case scenario, the modeled SST burned 3 times as much fuel per business-class passenger relative to recently certificated subsonic aircraft; in the worst case, it burned 9 times as much fuel compared to an economy-class passenger on a subsonic flight.”


  9. More Good News – a break from supersonic fantasies



    A very off topic locale for a long continuing on topic discussion of Asian aircraft plans in development

    Especially, ahem, in light of a crunch week of geopolitical maneuverings by the Chairmen

    « Russia’s Central Aerohydrodynamic Institute and UAC have recently reported successful completion of wind tunnel testing on scaled CR929 models, with their performance reportedly far exceeding aerodynamic design parameters. «

    « The CR929 is being closely watched in the West to see how the Beijing-Moscow tech and engineering alliance plays out in the skies. With a maximum take-off weight of 245 tons, the 63.3-meter long-haul plane will be able to fly 440 passengers in its maximum seating configuration and travel 12,000 kilometers non-stop at speeds of over 900 kilometers per hour.
    « Aviation data cruncher and consultancy Oliver Wyman noted in a recent report that Chinese carriers would have a combined fleet of 779 wide-body jets in 2029, around the time the CR929 is tipped to enter full-scale commercial service.

    Chen Yingchun, the CR929’s chief Chinese designer, has predicted 1,000 CR929 jetliners will be made and sold between the mid-2020s to 2045. He said the CR929 aims to wrest 10% of the global market for wide-body jets over the next 20 years, a space now dominated by Boeing and Airbus. »

    • I’m reminded of a line from the film “The Matrix”:
      “Do you hear that, Mr. Andersen? That’s the sound of inevitability…”.

      • @Bryce

        At least the discussions and plans for the CR929 are reality based for a definite industrial and commercial project

        Which call for or provoke reaction among EU US aviation industries

        The supersonic aircart fantasies are a diversion or a form of intra-billionaire gaming similar to let’s go Life on Mars wheeled out regularly by the usual suspects: Branson, Musk, Bezos

  10. Today Bloomberg reports:

    “To attract orders for the Max, Boeing has been offering some customers steep discounts, reduced upfront payments and other inducements …”

    • Bloomberg reported that United is going for the MAX-8…which means that the order can be (at least partially and potentially) taken from the low-to-zero-to-negative-margin “yard sale” parking lot of whitetails.
      “Come get your aircart at B-Mart”

      • I wonder if Boeing has some business insurance that covered the MAX accidents some, or also kicked in for The Covid-19 unforeseen pandemic…

  11. See my comments in your multi-news thread.

    I especially point to Boom’s early partnering with JAL, which is a source of advise on usability.

    (Which I take as both inside cabin and operational factors including reliability.)

    Boom is making good progress but needs to ensure it executes flawlessly. Its technology demonstrator should be a big help in learning.

    • Well I tend to take Bjorn on the tech end and his comment is a tech demonstrator does nothign for a full sized Boom.

      Concord in all its tech wonder (I am still amazed) demonstrated all you need.

      Commercially Boom is a Bust.

      Financially and technically Concord took the full backing of two countries to make it happen.

      Boomless has noting remotely close.

  12. Future certification hurdles for Boeing (and AB):
    “737 Max report calls for overhaul of Canada’s approval process for new planes”

    “Transport Canada was one of several international regulators that approved the new design, but with limited independent scrutiny. Under international agreements, Canadian regulators didn’t certify the new 737 Max themselves, but relied on data from the FAA, which Transport Canada verified.

    However, investigations in the United States found that Boeing withheld crucial information from the FAA about the plane’s design, including the faulty software, which meant other regulators were also misled. The FAA was also found to have outsourced much of its oversight of the 737 Max to Boeing’s engineers, allowing the company to approve its own design changes without disclosing risks associated with the new software.

    The 737 Max crashes have “stimulated reflection in Canada regarding the foreign aircraft validation process; specifically the level of involvement of [Transport Canada] in the process,” the committee says in the report’s conclusion.

    The report makes 14 recommendations to improve Canada’s oversight. Among them, the committee of Liberal, Conservative, New Democrat, and Bloc Québécois MPs said Transport Canada should be required to conduct a full recertification of any plane’s system that is connected to a modified design, such as new software. This would mean the regulator could no longer just verify the work of the FAA, but would have to scrutinize and certify any significant new design changes itself.

    The committee also recommended that airline pilots be more involved in the certification process, and that Transport Canada “review its policies to ensure that certification or validation of an aircraft does not occur until all significant issues or concerns are fully addressed.”

    In calling on Transport Canada to examine its relationship with the FAA, the report recommends that Canada “review its international agreements” that call for aircraft certification to be harmonized and streamlined. The report also recommends that Canada seek “additional technical assessment” during the validation of FAA certified planes.

    The report includes an additional recommendation from the NDP for a public inquiry into Canada’s approval of the plane, and why Ottawa didn’t ground it after the first crash in October, 2018, which killed 189 people off the coast of Indonesia. Grounding the plane after the first crash could have saved lives if regulators around the world followed suit.

    The report also includes submissions from Gilles Primeau, an expert in flight control systems, who said the design characteristics of the flawed software met “only the barest safety standards.” Mr. Primeau urged regulators to examine how design changes on new aircraft affect other aspects of the plane’s operations, rather than scrutinizing items – such as the software – in isolation.”


    • @Bryce

      Great link – a relief to get back to the real world after all the spacecart fantasies

      Just think – if Canada can be this cautious, calm and methodical, other countries can do as well if not better

      Other countries are no longer from any lingering habit required to rubber stamp the multiple many flaws in the FAA, in oversight regulation and certification, for these errors or this corrupt system is a particular product of administrative breakdown in the US, as is the corresponding decline in industrial manufacture quality, standard, and method

        • If this is intended to be some sort of sneer at the “off-topic” nature of this comment thread, I’d remind you that — just a week ago, in the last Boom article dated June 4 — you posted an off-topic comment on the KC-390 and the KC-46: in case you’ve forgotten, the text of your comment is below.

          If reply to your query:
          – The MAX can’t even reliably fly at subsonic speeds, not to mind supersonic.
          – The CR929 is currently planned to be a subsonic program…but you never know, the “resourceful reds” just might surprise the world with some on-the-fly program modifications.


          June 5, 2021

          And a side interest. KC-390 gets the cold shoulder and Brazil needs more Gen 4 fighters? Says a lot about what its about.
          Pretty amazing. Brazil has been invaded so many time just in the last year.
          And a side note on the responsibly of the KC-46 boom (no vision) issue.

          • @Bryce

            A lot of people are happier talking about fantasy SS aircarts that’ll never happen

            It gives they think a licence to dream – the last frontier etc

            Just as Bezos and the rest provide them with spacecart fantasies and get paid to do so – keeps the masses under the illusion

          • @Bryce

            Remember the poster has an unshakable faith in one airframer, hardly supported by fact or numbers.

    • Thanks Bryce,

      it’s good if Transport Canada wants to improve.
      Boeing and FAA can’t be trusted.
      Good for every regulator who didn’t re-certify the MAX yet. They should check the cert documents the FAA never checked. They should find more mistakes.

    • Thanks for the link, though it was not needed to know that
      the United/”Boom” SST is delusionWare; risible at a glance.

      That some persons can straight-facedly claim it’s going to happen is .. remarkable.

  13. Shopping at B-Mart can be an unpredictable experience:
    – Bargain Basement whitetails out in the parking lot, BUT:
    – 1500% markup on a part for a JAF KC-46…”16 times more than the U.S. Air Force paid for its latest versions”


  14. On the subject of hype (Boom, EVToL, etc.), Airbus’s hydrogen project has been revealed to be somewhat “fluffier” than many may have thought:

    “Airbus tells EU hydrogen won’t be widely used in planes before 2050”

    “It has not publicly said whether the technology will be ready in time for the European industry’s next major milestone – a replacement for the medium-haul A320 in the 2030s – but February’s briefing to EU officials appeared to rule this out.

    “Zero-emission hydrogen aircraft will be primarily focused on regional and shorter-range aircraft from 2035. Which means that current and future iterations of highly efficient gas turbines will still be required as we move towards 2050, especially for long-haul operations,” the presentation said.


    And without having to negotiate a paywall:


    For aviation, it makes sense to use green energy to produce SAF rather than LH2 — far less hassle and modification of existing technology/infrastructure.
    For ground-based transport, hydrogen is a very viable solution.

  15. Back in the real world

    With permission – subsonic life on US aircarts is getting worser



    Diversification and segmentation in the population may be a root cause, according to the experts

    « The FAA announced a zero-tolerance policy for bad behavior on planes in the days after the Capitol riot on Jan 6. The flight attendants union said at the time that those who stormed the building should not be allowed to get on flights home.

    During a town hall meeting late last month, FAA chief Steve Dickson said he was “appalled” at the behavior the agency had seen on planes and warned of “hefty fines and possible jail time.” »

  16. Hi,
    The new episodes are not showing up on my pod cast player any more…

    ¿is there a new feed or do you need to fine tune something?

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