Boom (YC W16) – Supersonic Passenger Airplanes • Hacker News Board

Re: Boom (YC W16) – Supersonic Passenger Airplanes

#291

Post by azernik » Mon, Mar 21, 2016, 9:12 PM UTC

jandrese wrote: post #252

spaceflunky wrote: post #80

Earlier quoted context omitted.

> We're building our prototype now—and will fly late next year. Will fly late next year? Where have I heard that one before...

A brand new advanced composite supersonic jet flying in a year's time? Color me skeptical. There are literally millions of things that need to be designed for this, and many of them will be bleeding edge. And this is from some tiny startup? A line like that sets off some big flashing red lights for me. Either they're incompetent and have grossly underestimated the amount of work needed to complete this, or it's a sca…

Not quite. According to [1], what they'll be flying is actually a one-third-scale prototype, which I'd imagine is a lot easier to build. And they've already been going for two years.

The real issue that I'm not seeing addressed is capital. No investors listed anywhere.

[1] http://www.bloomberg.com/news/articles/2016-03-21/this-aeros...

EDIT: Forgot to actually include the link.

Re: Boom (YC W16) – Supersonic Passenger Airplanes

#292

Post by neurotech1 » Mon, Mar 21, 2016, 9:13 PM UTC

jandrese wrote: post #252

spaceflunky wrote: post #80

Earlier quoted context omitted.

> We're building our prototype now—and will fly late next year. Will fly late next year? Where have I heard that one before...

A brand new advanced composite supersonic jet flying in a year's time? Color me skeptical. There are literally millions of things that need to be designed for this, and many of them will be bleeding edge. And this is from some tiny startup? A line like that sets off some big flashing red lights for me. Either they're incompetent and have grossly underestimated the amount of work needed to complete this, or it's a sca…

Lockheed Skunkworks have actually built prototype jets in under 2 years from go ahead to first flight. The A-12 (predecessor to the SR-71) went from contract to first flight in just over 2 years.

Didn't Burt Rutan make a composite aircraft from design to first flight in a year back in the 80s?

Getting the aircraft certified and into production is where most of the actual expense is.

Re: Boom (YC W16) – Supersonic Passenger Airplanes

#293

Post by bscholl » Mon, Mar 21, 2016, 9:16 PM UTC

neurotech1 wrote: post #242

bscholl wrote: post #192

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.

What type of intake design are you using? Comparable to the F-22A fixed square intakes? Are you using current turbofan engines (GE F110?) or something exotic?

Really good questions. We aren't sharing the details of the technical design quite yet (but will have more to say as we approach first flight).

Regarding engines: our first prototype (1/3 scale) flies with an off-the-shelf GE engine. For the product airplane, we're taking an existing subsonic engine and adapting it for supersonic flight. (Sorry, I know that's vague—much more to say about this in due time.)

Re: Boom (YC W16) – Supersonic Passenger Airplanes

#294

Post by bscholl » Mon, Mar 21, 2016, 9:16 PM UTC

melvinmt wrote: post #262

bscholl wrote: post #192

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.

How instrumental was YC in the development of Boom (money/advice wise)?

YC has been awesome and supportive in so many ways, far beyond money. 5 stars, would do again!! :-)

Re: Boom (YC W16) – Supersonic Passenger Airplanes

#295

Post by robotresearcher » Mon, Mar 21, 2016, 9:32 PM UTC

Retric wrote: post #232

robotresearcher wrote: post #168

Earlier quoted context omitted.

Data from an actual Concorde flight shows slowdown-to-land of around 45 mins, so around the same as a regular flight. http://www.blodtandsmidigt.com/concordeprofiles.html

Yes, but if the Concorde slows from Mach 2 to 0 over 45 mins then it's average may be ~mach 1. Which is faster than the average velocity of a normal 747. Granted, if the Concorde shows up and needs to circle the airport for 20 minutes then that's the same delay.

Those data show slowdown to subsonic over the first 10-15 mins of that period.

Re: Boom (YC W16) – Supersonic Passenger Airplanes

#296

Post by david-given » Mon, Mar 21, 2016, 9:33 PM UTC

aidenn0 wrote: post #243

david-given wrote: post #207

Earlier quoted context omitted.

I used to live under the Concorde flight path near Heathrow. Twice a day there'd be this crackling rumble and all the windows would shake; and this was flying subsonic. Concorde was really, really loud --- a lot of that was due to being a really old plane with old engines (aircraft have gotten way quieter since the 1970s), but even back then it was considered loud: http://news.bbc.co.uk/2/hi/uk_news/3581192.stm It wa…

I lived under the Concorde flight path near Dulles. I couldn't hear it, but we'd go out side to watch it fly over every now and then.

Modern aircraft are so dull! Efficient, safe, cheap, reliable even, relatively comfortable, but so boring. Even the A380 is a boring, and that's an office block with wings. How can something so incredible be so deadly dull?

...yeah, yeah, I know, being dull is an accomplishment in itself, and the duller aircraft are the better they are, and the one thing that every passenger pilot in the world wants is a thoroughly uninteresting flight. But, dammit, they're still so dull.

I miss Concorde.

Re: Boom (YC W16) – Supersonic Passenger Airplanes

#297

Post by robotresearcher » Mon, Mar 21, 2016, 9:36 PM UTC

petercooper wrote: post #183

zokier wrote: post #176

Earlier quoted context omitted.

Isn't the deaths-per-km generally zero prior to the first accident of any airliner?

How may airliners are in service for 24 years before their first fatal accident? (The 717 is up to 17 years. The A340 is almost at 24.)

There were 14 in-service Concordes. There are hundreds of most airliners.

After the single accident, the Concorde's death per passenger km record doesn't look so hot.

Re: Boom (YC W16) – Supersonic Passenger Airplanes

#298

Post by jandrese » Mon, Mar 21, 2016, 9:38 PM UTC

azernik wrote: post #291

jandrese wrote: post #252

Earlier quoted context omitted.

A brand new advanced composite supersonic jet flying in a year's time? Color me skeptical. There are literally millions of things that need to be designed for this, and many of them will be bleeding edge. And this is from some tiny startup? A line like that sets off some big flashing red lights for me. Either they're incompetent and have grossly underestimated the amount of work needed to complete this, or it's a sca…

Not quite. According to [1], what they'll be flying is actually a one-third-scale prototype, which I'd imagine is a lot easier to build. And they've already been going for two years. The real issue that I'm not seeing addressed is capital. No investors listed anywhere. [1] http://www.bloomberg.com/news/articles/2016-03-21/this-aeros... EDIT: Forgot to actually include the link.

That link didn't make me feel much better. They're planning to "tweak an off the shelf engine for supersonic speed". When I hear off the shelf engines, I think turbofans, but no amount of tweaking is going to make a turbofan work at supersonic speeds. It's possible they can get some military grade afterburning turbojets from somewhere, but it's not something you can buy off of the shelf.

Their webpage has a bunch of guys standing around what looks like a Vietnam-era jet engine.

Also, if they're planning to have something flying in 20 months, they should be beyond the cardboard and plywood mockup phase of development.

The more I see about this company the more I think it's a scam.

For comparison, the Concorde took about 21 years to develop. Granted, it was a massive clusterfuck, but they also had to solve a lot of issues along the way.

Re: Boom (YC W16) – Supersonic Passenger Airplanes

#299

Post by pacificmint » Mon, Mar 21, 2016, 9:38 PM UTC

bscholl wrote: post #266

nharada wrote: post #226

Earlier quoted context omitted.

Why do you think that other established players haven't entered this space (i.e. Boeing, etc)?

There's a lot of scorched earth in supersonics, since Concorde wasn't an economic success and the Boeing SST project was cancelled. Since then, there has been research on 300 seat Mach 2.4-Mach 3 vehicles, but these are extremely challenging. To make this happen and happen soon, you have to start much smaller than the established players usually consider. We're at 40 seats—that's the minimum economic size. Supersonic…

I had always thought that the small size of the Concorde was what made the per seat cost so expensive and held the Concorde back economically. So my expectation was that to be economically successful, you'd have to build a supersonic plane that carried more people.

Clearly you know more about this than me, but can you elaborate on why my view isn't correct?

Re: Boom (YC W16) – Supersonic Passenger Airplanes

#300

Post by Animats » Mon, Mar 21, 2016, 9:39 PM UTC

bscholl wrote: post #192

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.

1. How much money do you need to get to first flight?

2. How much money do you have?