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Boom (YC W16) – Supersonic Passenger Airplanes

boom.aero

381–390 of 488 posts

Re: Boom (YC W16) – Supersonic Passenger Airplanes

#381

Earlier quoted context omitted.

specially if the F-18 pilot is making sure that every bug smasher from Mount Whitney to the Mojave knows what true speed is. I've read and re-read that story so many times, each reading results in a fresh batch of goosebumps. I'd love to read the book (Sled Driver, I think?), but it is over $500 on Amazon. I wish they either ordered another print OR published as an ebook.

Yikes! I have two copies, having thought that I'd lost mine years ago -- bought a new one -- then found the original again.

Are you interested in selling one of them? If so I promise to give it a very good home, I still have books from my childhood in great condition.

Someone emailed me a pdf (thank you!) but I'd love to be able to have a physical copy too.

Re: Boom (YC W16) – Supersonic Passenger Airplanes

#382
post #246

Earlier quoted context omitted.

How are you reducing the boom? Are you widening part of the forebody to increase the local air temp & mach no to weaken the shock? What about redirecting the shock?

Sonic boom physics are subtle and counter-intuitive. High level, you: (1) keep the airplane as small and light as possible (reduces total shock energy) (2) carefully shape the fuselage and wings, so the shocks don't combine as strongly

NASA and Boeing have a design that has the engines on the upper part of the wings saying it reflects most of the boom upward. (see ninth paragraph) https://www.nasa.gov/aero/centers_tackle_sonic_boom.html

Re: Boom (YC W16) – Supersonic Passenger Airplanes

#383

Earlier quoted context omitted.

Actually, Concorde was too big : 100 seats. It worked NY/London but at ~$20k/seat they couldn't fill enough seats several times daily on other routes. Which means you can't have many airplanes, which means no economies of scale. With 40 seats and business class prices, the Boom airplane works on many more routes, which means we can make a lot of airplanes and enjoy economies of scale. Looking into the future, as fuel…

> It worked NY/London but at ~$20k/seat they couldn't fill enough seats several times daily on other routes. Your price is way off. http://www.airliners.net/aviation-forums/general_aviation/re...

From the link: "In the late 1990s I paid $11,000US each for several round trips."

That's about $16k when accounting for inflation, so $20k isn't too far off.

Re: Boom (YC W16) – Supersonic Passenger Airplanes

#384

Earlier quoted context omitted.

We have the same gas mileage (fuel per seat mile) as a lay-flat bed in business class. Since the aircraft can do nearly 3X as many trips in the same time, on net it's better. That's just the start of course—with more innovation on fuel efficiency the price and emissions both come down. $5,000 is what a business class ticket NY/London costs today, and many business travelers are able to do that routinely. This compare…

"Since the aircraft can do nearly 3X as many trips in the same time" Isn't that a bit optimistic? I would think it's closer to 2X. 2.6 times the airspeed, but why would turnaround time at the airport be any lower than for a comparably modern 'slow' airplane? For example, 6 hour flight plus 1 hour turnaround time versus 2.3 hours plus 1 hour turnaround time is more or less a factor of 2. For longer flights, the ratio…

Boarding should be faster, since it's only 40 seats and, ostensibly, roomier.

Re: Boom (YC W16) – Supersonic Passenger Airplanes

#385

Earlier quoted context omitted.

Great idea. The airline industry needs innovation around product and service to get out of it's current race to mediocrity. 2 questions: 1) Why 2.2 times the speed of sound? (Why not aim higher?) 2) Where will you get the capital? Seems like a very big ask compared to the typical company coming out of YC. Again - good luck! I would love to clip 4 hours from the SF to NYC flight.

Speed: Mach 2.2 is the fastest speed possible with known technology already accepted by the FAA. At that speed, you can have good takeoff performance (and comply with airport noise restrictions) and good cruise performance. We'd to build a faster V2 or V3, in due time. Capital: I can't comment quite yet. (Sorry)

Peter Theil regularly uses lack of aerospace innovation as a yardstick for slowing progress in Technology all the time[0].

He'd pretty much have to at least take the meeting.

[0] One example is the end of the future oped he wrote. http://www.nationalreview.com/article/278758/end-future-pete...

Re: Boom (YC W16) – Supersonic Passenger Airplanes

#386

Earlier quoted context omitted.

Great idea. The airline industry needs innovation around product and service to get out of it's current race to mediocrity. 2 questions: 1) Why 2.2 times the speed of sound? (Why not aim higher?) 2) Where will you get the capital? Seems like a very big ask compared to the typical company coming out of YC. Again - good luck! I would love to clip 4 hours from the SF to NYC flight.

Speed: Mach 2.2 is the fastest speed possible with known technology already accepted by the FAA. At that speed, you can have good takeoff performance (and comply with airport noise restrictions) and good cruise performance. We'd to build a faster V2 or V3, in due time. Capital: I can't comment quite yet. (Sorry)

Peter Theil regularly uses lack of aerospace innovation as a yardstick for slowing progress in Technology all the time[0].

He'd pretty much have to at least take the meeting.

[0] One example is the end of the future oped he wrote. http://www.nationalreview.com/article/278758/end-future-pete...

Re: Boom (YC W16) – Supersonic Passenger Airplanes

#387
post #240

Hi - I'm Blake, Founder/CEO at Boom. After watching no tangible progress in supersonics since Concorde was shut down, I started Boom because I want supersonic flight in our lifetime. Not just as a private jet, but something most anyone can afford to fly. Will try to answer as many questions here as I can.

Elon Musk says that eventually we will move to VTOL supersonic electric jets, but he is too busy with other projects to implement it. Have you thought about this idea, and in what time frame do you think someone might try to implement it? Elon's basic idea is that air-breathing jets are limited to altitudes at which oxygen tops out, and then are mostly fighting drag from nitrogen. Electric ones can go to higher altit…

Yeah but you are getting 50:1 difference in energy density between hydrocarbon fuel and battery. Also, vertical takeoff is extremely inefficient because a wing can generate a lot of lift compared to drag. this in addition to the fact that a vertical lift system is only used during take off and landing while being dead weight the rest of the trip.

even elon can't override physics

Re: Boom (YC W16) – Supersonic Passenger Airplanes

#388

Hi - I'm Blake, Founder/CEO at Boom. After watching no tangible progress in supersonics since Concorde was shut down, I started Boom because I want supersonic flight in our lifetime. Not just as a private jet, but something most anyone can afford to fly. Will try to answer as many questions here as I can.

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Re: Boom (YC W16) – Supersonic Passenger Airplanes

#389

Hi - I'm Blake, Founder/CEO at Boom. After watching no tangible progress in supersonics since Concorde was shut down, I started Boom because I want supersonic flight in our lifetime. Not just as a private jet, but something most anyone can afford to fly. Will try to answer as many questions here as I can.

Im thrilled to see something like this taking flight, congrats! I have two questions: 1) Can you tell us about your start-up process? Aside from your all-star team, I can't even imagine how you could have brought this to reality. I can't even imagine how much capital and space a prototype would have taken. At what point did you decide that it was time to apply to YC? Were there other investors? How much design work d…

[deleted]

Re: Boom (YC W16) – Supersonic Passenger Airplanes

#390
I think what you guys are doing is amazing and the world is due for airlines like Boom. I'm also happy to see that this venture is backed by YC. This is a huge step forward. Your prices bite a little and will likely be out of range for typical travelers but I'm sure this can be worked on. Is the airplane designed completely from scratch or will you be basing your engineering work on the designs of Concorde planes in some way, shape or form?
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