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Boom supersonic jet readies for rollout

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Re: Boom supersonic jet readies for rollout

#241

Post by new_realist »

jjeaff wrote: post #81
new_realist wrote: post #76

The biggest time sink when traveling between continents is the jet lag. A faster jet doesn’t fix that, it only costs more and pollutes more.

The new 787 has made her lag a lot better with better air quality, timed, dimming cabin lights and a few other comfort trucks, it definitely takes the edge off.

Jet lag, for me, is more about circadian rhythm disruption than air quality. That’s where sleeping on a longer flight is much more preferable to taking a shorter, faster flight and then suffering until one can get into a blacked out hotel room. But in either case the downtime would be similar, I think.

Re: Boom supersonic jet readies for rollout

#243

Post by notahacker »

Already__Taken wrote: post #234
notahacker wrote: post #194

Earlier quoted context omitted.

Sure, but I don't see a startup called Boom changing the political landscape around sonic boom concerns, particularly not in an era where there's also a lot of environmental lobbying.

if they revive the noise implications they might well manage to change it. IMO those restrictions are also because it wasn't an American jet so it kept the competition out.

Agreed on both points, but they're fighting against the physics of sonic booms, not just Concorde's noisy turbojet [a solved problem] so I wouldn't bank on it, and lobbying against Boeing as well as an environmental lobby that's far more influential now than in the seventies.

Several European states without commercial airframers introduced supersonic overflight bans too and the Anti Concorde Project started in the UK so I don't think the argument it was all protectionism stands up anyway.

Re: Boom supersonic jet readies for rollout

#245

Post by jacquesm »

adev_ wrote: post #163
alfalfasprout wrote: post #118

Earlier quoted context omitted.

The reason for that is that the concorde used afterburners (basically, pump fuel into the high speed exhaust for extra thrust) which are incredibly inefficient. Great for a fighter jet where you need a sudden burst of extreme thrust, but not something you want a long-haul airliner to use. Boom uses turbofan engines to reach supersonic speeds which are much, much more efficient. In fact, many airliners could theoretic…

> The reason for that is that the concorde used afterburners (basically, pump fuel into the high speed exhaust for extra thrust) which are incredibly inefficient. To put things in perspective, Concorde was using two Olympus engines designed originally in the 50s. It was already a marvel that they can run for such a range at Mach 2.0 when designed 70 years ago. A lot of things improved since. Most fighter jets can sup…

Concorde used four engines. Two engine ETOPS over water wasn't a thing back then, first real relaxation of that rule was in '76.

see: https://en.wikipedia.org/wiki/ETOPS

Re: Boom supersonic jet readies for rollout

#246

Post by ekingr »

TylerE wrote: post #106
axaxs wrote: post #105

Earlier quoted context omitted.

I'm still hoping for rail. It's much more carbon friendly, and has the opportunity to be way less stressful. I'd do 18 hours on a NY to LA if I could walk around, eat, talk, sleep, etc over a 5 hour misery ride in an airplane any day.

A single NY-LA route alone would cost over $500 billion. High speed rail is well $100m/mile, just for the track.

That seems too high. I'd rather say in the order of c.$100bn.

In France the average cost is €15m/km, and that's for extremely high standards / constraints (350km/h or 220mph nominal speed, incl. barriers & bridges for wildlife)

Re: Boom supersonic jet readies for rollout

#247

Post by jacquesm »

jlg23 wrote: post #186
kolinko wrote: post #183

Earlier quoted context omitted.

12 hours is a lot, but for shorter distances most people would prefer a good train to a plane. Living in Europe, I will take 4-5 hour train ride compared to a 1h flight, most of my friends as well. Many people will also prefer 5-8 hour 100mph train ride to 1h plane ride due to comfort, price and carbon footprint.

Well... price-wise, in lots of Europe, taking a plane is cheaper.. What really made the difference for me is that the 4-5 hour train ride is done after 4 to 5 hours. My 1 hour flight starts 3 to 3.5h before the flight to get to the airport and through security and at the destination, after de-boarding, I'll spend another hour for security and to get from the airport to my actual destination.

Plane only seems cheaper in many cases. Shuttle to and from the airport can be as expensive or even more expensive than that flight. Frequent delays / cancelled flights, check in misery, security theater and so on. If possible and available I'm more than happy to take the Thalys, ICE or TGV.

Re: Boom supersonic jet readies for rollout

#248

Post by jacquesm »

flyGuyOnTheSly wrote: post #115
na85 wrote: post #102

Earlier quoted context omitted.

I think the real problem is that the Concorde wasn't fast enough to justify the cost. Whether you can fly JFK-CDG in 8 hours or 4 hours, when you factor in how irritating airports are, parking, security line ups, waiting for baggage, etc, it still takes all day to make the trip. Might as well save several thousand dollars and take a longer flight. I believe they would have to cut the flight time down to about an hour…

The concorde didn't fail because it was expensive. It ran profitably for 27 years. [0] It failed because it crashed and killed 109 people 3 years before they threw in the towel. [1] [0] https://en.wikipedia.org/wiki/Concorde#Operating_economics [1] https://en.wikipedia.org/wiki/Air_France_Flight_4590

It crashed because of a fault on another airplane, a 5 Kg titanium strip from a DC10 entered the wing at very high speed. Not a lot of aircraft of the day would have survived such an impact.

Re: Boom supersonic jet readies for rollout

#249

Post by adventured »

TylerE wrote: post #101
JKCalhoun wrote: post #68

Earlier quoted context omitted.

Yeah, much more excited if there were talk of high-speed rail criss-crossing the U.S.

High-speed rail isn't high speed enough. Even with way faster than current tech and NO stops you'd still be looking at taking 12+ hours for what a plane can do in 5. That's ignoring the trillions it would cost. The US does not have the population density to make HSR viable.

> The US does not have the population density to make HSR viable.

The Democrats, after they take the Senate and Presidency, should launch a $1-$1.5 trillion regional HSR development project, partnering with Japan.

Here are the regional routes, generally speaking, that make tremendous sense and should be built this decade:

Oklahoma City, Dallas Ft Worth, San Antonio, Austin, Houston

San Diego, Los Angeles, Phoenix, Las Vegas, Bay Area, Sacramento

Milwaukee, Chicago, St Louis, Indianapolis, Detroit, Cleveland, Louisville, Cincinnati, Columbus, Pittsburgh, Philadelphia, Washington DC, Baltimore, New York City, Boston

Arguments can be made for linking up New Orleans initially; then later using that to link into Florida and Atlanta. Later on you'd link Atlanta to Nashville, and then Nashville to Louisville, completing the Texas to NYC connection. You'd later take Dallas or San Antonio out to El Paso, and then to Tucson & Phoenix, and then to Los Angeles, completing Texas to California. You could also debate Atlanta to Charlotte to Richmond to DC, completing Texas to DC & NYC by another path and creating an easy link from NYC to Miami. No idea what to do about Portland, Seattle, Denver and a few others.

If you build the three major regional HSR sections, you get a de facto national trivially with just a few more connections.

Ideally we would work with Canada and they'd simultaneously fund HSR using the same tech from Japan for max compatibility, and we'd link across the border to Toronto (and they'd link Toronto, Ottawa, Montreal, Quebec City.

This can be done. All it requires is the Democrats to have the gumption to steamroll the zoning / regulatory / environmental bullshit out of the way using executive orders and being abusive with federal power as necessary to the loads of idiots that will inevitably try to get in the way. Knock them down, push them out of the way, build the fucking rail. We might get one good shot at doing it before we drown in debt and it's too late (ie we might as well drop another trillion dollars plus in debt into the never-to-be-repaid ocean).

Re: Boom supersonic jet readies for rollout

#250

Post by _0ffh »

C1sc0cat wrote: post #219
agurk wrote: post #171

Earlier quoted context omitted.

Looking at the Concorde's fuel usage taxing is only part of the picture. All turbine engines are very inefficient at low power outputs due to the need to use energy to create sufficient compression for them to function. On top of this the Olympus engines generated a lot of thrust at idle, so much so that only two were used for taxing and it was still apparently tricky to control. While cruising at supersonic speeds t…

That's why you have tugs to move jets around - back in ww2 the Me226 was towed up to its start point on the runway by a Kitenkrad (and in some cases horses) to save fuel and engine life. I think the industry was thinking of having electric tugs or motors built into the plane to move passenger jets around on the ground to save the fuel used getting from the stand to the start of the runway.

You narrowly missed the opportunity to write "Kittenkrad", which sounds like the cutest form of transport yet conceived. Or, of course, "Kettenkrad", the german half-tracked motorcycle/tractor hybrid from WW2.
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