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Boom XB-1 First Supersonic Flight [video]

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

#251

Post by nashashmi »

cromulent wrote: post #121

“Currently, all civil aircraft flights are prohibited from operating above Mach one speeds over land in the United States.” [1] Mike Bannister’s excellent book Concorde talks at length about how “handsomely profitable” the BA service was (as opposed to the Air France one) from 1984 until the 2000 crash and subsequent grounding put them in to a spiral where keeping enough people certified was too expensive. One part o…

If Airforce One presidential plane is assigned to a sound-breaker, people will love the sound that comes from it. “Look the president is flying above us” people will say in excitement.

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

#252

Post by echoangle »

jjk166 wrote: post #213
mppm wrote: post #55

Earlier quoted context omitted.

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

There actually is still significant lift. We define the edge of the atmosphere to be where the lift to drag ratio of a plane would be less than 1 below orbital velocity (ie if you were going fast enough to lift your weight with conventional wings you'd be in orbit), so you can't fly conventionally in space but lift might still be generating a force which is significant compared to your craft's weight.

Well the assumption was that there is no drag because the air density is so low. You can’t just say there’s no drag but still assume that you get lift. Your lift/drag ratio won’t go up infinitely just because you’re flying higher.

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

#253

Post by two_handfuls »

joemi wrote: post #173

I wonder if they have cameras to show the pilot everything they can't see when taking off/landing, since it looks like it has the same forward-visibility issues as the Concorde (without the Concorde's moveable nose -- I think?). Pretty cool though! It was disappointing that the Concorde (along with commercial supersonic flight in general) was retired around the time I was becoming an adult and could begin to contempl…

They do, yes. Visible in Scott Manley's video.

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

#254

Post by benced »

actionfromafar wrote: post #117
thepaulmcbride wrote: post #112

The angle of attack at both takeoff and touch down is pretty wild!

I can't let go of the suspicion that this could become some kind of military (drone or not) airframe.

I can't think of a single aerospace company that is not dual-use. I doubt Boom is building with that in mind but if they're around in 50 years, I'd be shocked if they did not have a thriving defense business.

(which I think is good but ymmv)

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

#255

Post by echoangle »

JumpCrisscross wrote: post #90
EA-3167 wrote: post #32

Earlier quoted context omitted.

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…

> Who are these people who wouldn't rather take a sleeping pill or futz around on their laptop instead? Me. Time is time. A lay-flat seat intercontinental is already $10+ k within weeks of departure, point to point. Not having to plan around sleeping on the plane or whatnot makes international trips feel domestic.

So how much would you be willing to pay additionally to get from a 10 hour flight to a 5 hour flight? More than 5k?

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

#256

Post by chgs »

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…

Last time I flew from Heathrow it was 45 minutes from car to take off, and that was with a 20 minute door close.

It doesn’t take 2 hours to go through security , certainly not in the first class section in any case.

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

#257

Post by dghlsakjg »

sedatk wrote: post #159
cromulent wrote: post #121

“Currently, all civil aircraft flights are prohibited from operating above Mach one speeds over land in the United States.” [1] Mike Bannister’s excellent book Concorde talks at length about how “handsomely profitable” the BA service was (as opposed to the Air France one) from 1984 until the 2000 crash and subsequent grounding put them in to a spiral where keeping enough people certified was too expensive. One part o…

Concorde experiences one fatal crash in 27 years: entire product line gets cancelled. Meanwhile, Boeing 737 MAX... ¯\_(ツ)_/¯

The Concorde manufacturing was cancelled in the 1970s. The crash was in 2000. The last flight was in 2003.

They didn't stop flying due to a crash. It was the money.

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

#258

Post by chgs »

senordevnyc wrote: post #229
JumpCrisscross wrote: post #90

Earlier quoted context omitted.

> Who are these people who wouldn't rather take a sleeping pill or futz around on their laptop instead? Me. Time is time. A lay-flat seat intercontinental is already $10+ k within weeks of departure, point to point. Not having to plan around sleeping on the plane or whatnot makes international trips feel domestic.

I keep seeing you using this $10k figure, where is that coming from? I’m fortunate to fly intl biz class a lot, and I rarely see prices that high. In September I flew SG from NYC to Singapore in biz class for $4k RT.

I spend more than that in premium economy with no Saturday stay and last minute like many business travellers.

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

#259

Post by echoangle »

two_handfuls wrote: post #250
__loam wrote: post #118

Earlier quoted context omitted.

The military has had supersonic aircraft since the 1950s, why would they care about this?

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.

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

#260

Post by chainingsolid »

bookofjoe wrote: post #204

This thread: https://www.pprune.org/tech-log/423988-concorde-question.htm... which covers over a decade, contains many hundreds of entries from Concorde pilots, crew, flight engineers, cabin crew, maintenance personnel, and air traffic control recounting anecdotes and amazing things about the plane and events surrounding it. I started reading it and spent about three absorbing hours fascinated and amazed, unable to s…

Someone linked this a few days ago on another post and I've been reading it scene. It's been a very interesting read. I do recommend.
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