Boom XB-1 First Supersonic Flight [video] • Hacker News Board

Re: Boom XB-1 First Supersonic Flight [video]

#321

Post by jimjimjim » Wed, Jan 29, 2025, 12:54 AM UTC

OnlineGladiator wrote: post #249

pembrook wrote: post #228

Earlier quoted context omitted.

Endless pessimism, even in the face of evidence to the contrary is a hallmark of HN. Thank you for continuing the tradition. May you never hold out hope for anything positive in the future.

Blind optimism is just as obnoxious as blind pessimism - both are based on ignorance. Boom still hasn't solved the 2 hardest problems after nearly a decade. Currently regulations prohibit supersonic flight over land. It's a total guess whether or not they'll be able to overcome this, but I remain skeptical both of their noise claims and their ability to overturn legislation. Also they don't have a real plan for an en…

"Over land" in this case is just the US. and that was driven more to hamstring the uk/euro Concord. Sell this to rich playboys in the mediterranean or middle east.

Re: Boom XB-1 First Supersonic Flight [video]

#322

Post by sfblah » Wed, Jan 29, 2025, 12:58 AM UTC

I didn't see any data on the loudness of the sonic boom. Isn't an important part of the idea here to diminish that significantly?

Re: Boom XB-1 First Supersonic Flight [video]

#323

Post by scythe » Wed, Jan 29, 2025, 1:00 AM UTC

cryptonector wrote: post #286

scythe wrote: post #275

Earlier quoted context omitted.

Noticeable is certainly a way of putting it. https://en.wikipedia.org/wiki/Oklahoma_City_sonic_boom_tests >However, in the first 14 weeks, 147 windows in the city's two tallest buildings, the First National Bank and Liberty National Bank, were broken. If a sonic boom is "noticeable", that's one thing. But the problem is that even from cruising altitude they're shockingly loud. If the sonic boom is merely bearable, th…

GP was asking about this flight's sonic boom. That's the whole point of Boom: to make supersonic airplanes with small sonic booms.

I don't see the problem? I was just saying that "not noticeable" is a really high bar to set for a supersonic flight.

Re: Boom XB-1 First Supersonic Flight [video]

#324

Post by nine_k » Wed, Jan 29, 2025, 1:07 AM UTC

__loam wrote: post #239

actionfromafar wrote: post #200

Earlier quoted context omitted.

If it's cheap to produce.

The F16 is already cheap, proven, integrated with everything, and available in great numbers. The Air Force also has a super sonic bomber in the B1 lancer, and a mass produced supersonic stealth fighter/bomber in the F35, which is actually pretty cost effective despite its public perception. Maybe there's a place for a large supersonic transport but the Air Force also has a lot of very heavy logistics aircraft alread…

F-16 is a beauty, but it can't do Mach 2 for a prolonged time; it actually can't even do Mach 1.1 for a prolonged time.

F-22 is a marvel, and can fly supersonic for much longer, but its cost is exorbitant, and it's not even produced any more.

F-35 is more economical but it literally can fly supersonic for a minute or two with the currently installed engines.

Re: Boom XB-1 First Supersonic Flight [video]

#325

Post by blktiger » Wed, Jan 29, 2025, 1:07 AM UTC

sfblah wrote: post #322

I didn't see any data on the loudness of the sonic boom. Isn't an important part of the idea here to diminish that significantly?

I think you are confusing Boom with NASA’s QUESST project. https://www.nasa.gov/mission/quesst/

Re: Boom XB-1 First Supersonic Flight [video]

#326

Post by ghaff » Wed, Jan 29, 2025, 1:11 AM UTC

wongarsu wrote: post #314

kridsdale1 wrote: post #271

Earlier quoted context omitted.

I guess the target market is those who feel about the opportunity cost of another $5,000 the way you and I do about another $5.00

For companies with executives that travel a lot (visiting different offices or store locations or lots of in-person client visits across the country) it might be literally saving them money. And even if it doesn't save them money, the prestige and the fact that the people who approve the purchase are the same people who get to use it help justify the cost

Lots of companies have execs who do those things that still don't fly private jets today and may not even have execs who always fly business class unless they have the status to routinely get upgraded. Certainly no company I've ever worked for and I've worked for some pretty large ones.

Re: Boom XB-1 First Supersonic Flight [video]

#327

Post by wongarsu » Wed, Jan 29, 2025, 1:11 AM UTC

reaperducer wrote: post #209

alex_duf wrote: post #120

Earlier quoted context omitted.

I assume the question was about the questionable economics of running a super-sonic airplane profitably. The Concorde was notorious for bleeding money. Maybe the premium aspect will be enough, given that we have a bigger and bigger chasm between rich and poor, or maybe the economics of running it won't compete against sub-sonic, lower fuel consumption planes.

The Concorde was notorious for bleeding money. I see this stated all the time on HN, yet there's a whole section at the top of this very comments thread where people are talking about how very profitable the Concorde was. One person quoted the line "There were times, in fact, when the seven aircraft in the fleet would contribute around 40 per cent of BA’s entire profits."

My understanding is that it was profitable if you got the aircraft for free and already had pilots capable of flying them.

If the Concorde had been an actual financial success they would have developed it further and made a successor. And if BA and Air France had thought that the Concorde would continue making them money they wouldn't have retired it after one tragic accident in 30 years of operation. The 737 Max is still being made after much worse.

Re: Boom XB-1 First Supersonic Flight [video]

#328

Post by kristofferR » Wed, Jan 29, 2025, 1:17 AM UTC

echoangle wrote: post #27

Why are some camera shots so dull? Is that a HDR problem?

Likely LOG settings in the cameras, a color profile aimed at color correction. If LOG footage is not color corrected it looks like that.

https://www.youtube.com/watch?v=3ap8k564N_w

https://en.wikipedia.org/wiki/Log_profile

Re: Boom XB-1 First Supersonic Flight [video]

#329

Post by skgough » Wed, Jan 29, 2025, 1:18 AM UTC

hugs wrote: post #237

I haven't seen anyone directly address it in the comments here (or in the video): was an audible sonic boom noticeable on the ground during today's test flight?

this plane doesn't look like it was made to produce a low boom. It has a very distinct von Karman ogive [1] fuselage and typical delta wings. I would guess that it's shape is primarily optimized for fuel efficiency at 1.5 mach or above.

If you take a look at NASA's low boom demonstrator [2], you can see that it's much skinnier and the nose is crazy elongated. This is intended to break up the bow shock into multiple parts, thereby decreasing the amount of energy each one has.

[1] https://en.wikipedia.org/wiki/Nose_cone_design#Von_K%C3%A1rm... [2] https://en.wikipedia.org/wiki/Lockheed_Martin_X-59_Quesst

Re: Boom XB-1 First Supersonic Flight [video]

#330

Post by two_handfuls » Wed, Jan 29, 2025, 1:25 AM UTC

echoangle wrote: post #259

two_handfuls wrote: post #250

Earlier quoted context omitted.

If Boom succeeds in making a supercruise engine that can stay supersonic without needing afterburners, then the military may be interested because that will be cheaper than their current engines that need afterburners and use more fuel.

How is that special? The military already has the F-22 which can supercruise just fine. Or the Eurofighter if your military isn’t the USAF. And also, fuel cost is probably the last concern of an Air Force. Maybe logistics of supplying fuel in an actual war is important, but I think the money for buying the fuel itself is basically zero compared to maintenance and getting the plane in the first place.

Thank you, I did not know that.