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Boom XB-1 First Supersonic Flight [video]

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

#51

Post by NegativeLatency »

dylan604 wrote: post #36
bangaroo wrote: post #12

Earlier quoted context omitted.

i don't disagree with any of that, i'm extremely skeptical that they will ever scale this up however: there is, now. this is a civil aircraft flying supersonic, which is still some sort of interesting fact.

Do none of the private jets like G6s or whatever fly supersonic?

No, you can kinda tell by the planes shape how fast it can go. https://en.wikipedia.org/wiki/Area_rule

Certainly they're fast, wikipedia says the the G650 can get to mach 0.9, but it's called the sound barrier for a reason. https://en.wikipedia.org/wiki/Sound_barrier

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

#53

Post by rbanffy »

bangaroo wrote: post #49
talldayo wrote: post #41

Earlier quoted context omitted.

"in a long time" kinda doesn't matter to me. America hasn't built a supersonic bomber "in a long time", you'll have to excuse me for not caring. The value of such a weapon is dubious and only made sense in a hype-laden Cold War environment. Similarly I don't think we've learned the lessons of the Concorde yet. Not only do people not need hypersonic flight, it's going to create a premium class of hydrocarbon emissions…

as a person who likes airplanes (and airliners in particular,) i think it's cool that a commercially-focused aircraft manufacturer has managed to return to a type of flight that has primarily been relegated to military operations for a very long time today i am not thinking any further ahead than "wow, they did a really cool thing and made a supersonic test platform for a commercial airliner." there will be lots of f…

I can't wait to see NASA's one. What I really hope is Mach 2 at altitudes higher than the Concorde, in order to minimize sonic booms on land. Even if we never get to fly supersonic over land again, a Mach 2 plane that can cross the Pacific would be incredible.

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

#54

Post by bangaroo »

dmitrygr wrote: post #16
bangaroo wrote: post #12

Earlier quoted context omitted.

i don't disagree with any of that, i'm extremely skeptical that they will ever scale this up however: there is, now. this is a civil aircraft flying supersonic, which is still some sort of interesting fact.

[flagged]

i don't. i'm explicitly choosing not to be pedantic and instead hoping you'll take what i say as what it obviously is intended to mean and not as a very specific and accurate phrasing to be disassembled and torn apart without acknowledging the overall intent of the message.

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

#55

Post by mppm »

Ajedi32 wrote: post #38
hnuser123456 wrote: post #31

Earlier quoted context omitted.

Huh. The longest flights are around 10,000 miles. They usually cost over $1000. Fuel apparently accounts for about 25% of ticket price on long haul, so $250 in fuel normally. To do that in 4 hours is to travel 2,500 mph. Naively, traveling twice the speed requires 8x the power, so going over 4x the usual 550mph should mean over 64x more fuel burn, or $16,000 in fuel alone. Maybe a bit less since drag doesn't grow qui…

Once you get out of the atmosphere, drag (and fuel consumption) is ~0. So theoretically possible, but I'm not sure if that's what he was talking about. Certainly Overture won't be capable of that.

Once you get out of the atmosphere, lift is ~0 too.

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

#56

Post by ctippett »

EA-3167 wrote: post #32
dylan604 wrote: post #6

I know nothing about Boom. Why is this impressive? We've achieved supersonic for passengers before. Are we meant to be interested just because someone is taking up the mantle again, or is there some new design that makes it impressive?

There are some interesting technological developments around fuel efficiency and minimizing the "sonic boom" that's felt on the ground. Neither of those killed Concorde though, because the entire idea of Concorde turned out to be incredibly faulty. MOST people weren't in such a hurry to get from point A to point B that they'd pay 5x-10x a normal business/first class ticket to cut a trip down by 50% or so. The intende…

On the live cast the presenter mentioned Boom have already secured ~130 pre-orders, including United Airlines. Not bad considering the Concorde anticipated 100+ orders but only manufactured a fraction of that.

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

#57

Post by foobarqux »

doctoring wrote: post #15
dralley wrote: post #5

Is the goal to be able to supercruise, or are they just going to be to waste tons of fuel on afterburning like the Concorde?

I had the same question. From their FAQ ( https://boomsupersonic.com/faq ): > Will Overture use afterburners like Concorde? > No. Overture will fly without the use of afterburners, meeting the same strict regulatory noise levels as the latest subsonic airplanes. The airliner will be powered by the Symphony propulsion system. Symphony will be a medium-bypass turbofan engine designed and optimized for environmentally a…

> ... meeting the same strict regulatory noise levels as the latest subsonic airplanes

Extremely dishonest: as far as I can tell (CFR title 14, B36.5) there are no specific noise level regulations for subsonic cruise flight (i.e. not take-off and landing) because you can't hear subsonic aircraft at cruise altitude. On the other hand, however, you will be able to hear sonic booms.

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

#58

Post by dylan604 »

NegativeLatency wrote: post #51
dylan604 wrote: post #36

Earlier quoted context omitted.

Do none of the private jets like G6s or whatever fly supersonic?

No, you can kinda tell by the planes shape how fast it can go. https://en.wikipedia.org/wiki/Area_rule Certainly they're fast, wikipedia says the the G650 can get to mach 0.9, but it's called the sound barrier for a reason. https://en.wikipedia.org/wiki/Sound_barrier

That makes sense. I've known that private jets fly faster than typical commercial jets as well as flying at higher altitude.

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

#59

Post by giarc »

anothertroll456 wrote: post #39
hangonhn wrote: post #22

Earlier quoted context omitted.

No. I don't think that's correct. The Concorde used its afterburners during take off and to get through the transonic region, where the drag is very heavy. Once you've gone past that the drag drops. At that point the Concorde can turn off the after burners. Source: https://www.heritageconcorde.com/concorde-engine-re-heats

[flagged]

Not really, that's like saying "they relied on closing the doors to the aircraft to achieve supersonic flight". Both happened, but aren't related if I'm reading the comments correctly.
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