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A New Engine Could Bring Back Supersonic Air-Travel (economist.com)
An anonymous reader shares a report (may be paywalled): Every morning, time once was, a giant roar from Heathrow Airport would announce the departure of flight BA001 to New York. The roar was caused by the injection into the aircraft's four afterburners of the fuel which provided the extra thrust that it needed to take off. Soon afterwards, the pilot lit the afterburners again -- this time to accelerate his charge beyond the speed of sound for the three-and-a-half hour trip to JFK. The plane was Concorde.
Supersonic passenger travel came to an end in 2003. The crash three years earlier of a French Concorde had not helped, but the main reasons were wider. One was the aircraft's Rolls-Royce/Snecma Olympus engines, afterburners and all, which gobbled up too much fuel for its flights to be paying propositions. The second was the boom-causing shock wave it generated when travelling supersonically. That meant the overland sections of its route had to be flown below Mach 1. For the Olympus, an engine optimised for travel far beyond the sound barrier, this was commercial death.
That, however, was then. And this is now. Materials are lighter and stronger. Aerodynamics and the physics of sonic booms are better understood. There is also a more realistic appreciation of the market. As a result, several groups of aircraft engineers are dipping their toes back into the supersonic pool. Some see potential for planes with about half Concorde's 100-seat capacity. Others plan to start even smaller, with business jets that carry around a dozen passengers. The chances of such aircraft getting airborne have recently increased substantially.
Supersonic passenger travel came to an end in 2003. The crash three years earlier of a French Concorde had not helped, but the main reasons were wider. One was the aircraft's Rolls-Royce/Snecma Olympus engines, afterburners and all, which gobbled up too much fuel for its flights to be paying propositions. The second was the boom-causing shock wave it generated when travelling supersonically. That meant the overland sections of its route had to be flown below Mach 1. For the Olympus, an engine optimised for travel far beyond the sound barrier, this was commercial death.
That, however, was then. And this is now. Materials are lighter and stronger. Aerodynamics and the physics of sonic booms are better understood. There is also a more realistic appreciation of the market. As a result, several groups of aircraft engineers are dipping their toes back into the supersonic pool. Some see potential for planes with about half Concorde's 100-seat capacity. Others plan to start even smaller, with business jets that carry around a dozen passengers. The chances of such aircraft getting airborne have recently increased substantially.
F-22 has engines that provide so much efficient thrust, it can cruise at supersonic speeds without using the afterburner.
So you just need to scale up the F-22 to carry 100 people!
I love progress. A plane that can go past the speed of sound and only half the number of seats of Concord? Sounds like a great plan.
30 minutes to any city on earth sounds pretty good, and I am pretty sure SpaceX will be getting at least one such commercial flight out in the next five years or so... they also can carry 100 people at a time, and passengers get a free sub-space visual to boot.
Even supersonic would look pokey next to that.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
>> I am pretty sure [thing promised by company will happen] in the next five years
No wonder companies continue advertise here: Slashdot remains a target-rich environment filled with consumers who are easily persuaded by flimsy promises. Why don't we go ahead an speculate on which flying cars we'll have in five years while we're at it?
Others plan to start even smaller, with business jets that carry around a dozen passengers. The chances of such aircraft getting airborne have recently increased substantially.
Billionaires fly at super sonic. Trickle down to us peasants? Nah! We don't need to get anywhere fast because our time is worthless. It just takes time out of our TV, video games, sex, family, and other worthless activities.
I keep paring my life back more and more so that I don't go into deeper debt (student loans: that BS CS from state was more expensive in the end and the pay wasn't good enough to compensate. High paying jobs aren't recruited from state.). But I keep getting behind. Medical costs keep skyrocketing. I'm told I need to go back to school! WTF?! Rent keeps going up 3% or more every year but my pay stays the same.
Buy a house?! Ahahahahaha! UNAffordable.
My retirement savings is in the NEGATIVE - Thanks TRUMP!
Mu "stupid" high school classmate who went to trade school? He went for CNC machining. Apprenticed an after as many years as I have been in school and working, he's making $100K+ working LESS hours than I am.
NO STUDENT DEBT!!
Yeah, he's bored shitless ('monkey presses the button' as he says. Engineers do the programming.) but he's doing better and actually has room for advancement. He's starting to do the programming for the engineers - they don't want to do it.
Me? I'm stuck in a dead end support job - "have you tried turning it off and on again" - job. No one EVER gets promoted to development jobs from here because they get those people from MIT and Ivy League schools directly.
tower this is ghostrider requesting a flyby
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Slashdot remains a target-rich environment filled with consumers who are easily persuaded by flimsy promises
What is flimsy about such a prediction? The BFR is flying just next year. It's not hard to see them putting up at least one commercial flight within the next five as a test of viability, after all it has a huge attraction for flights like NYC to Australia which otherwise take a very long time. Tickets would sell like hotcakes.
Why don't we go ahead an speculate on which flying cars we'll have in five years while we're at it?
That's actually about five to ten years out, made possible by self driving car tech. it was never going to happen when humans were the ones flying the car, which is why we've never really see that come about even tough every now and then you read about flying car designs. Just like self driving cars, the first applications will be taxis more than personal transport, though that too will come.
What never ceases to amaze me about Slashdot is that people used to technology, can be such negative luddites despite years and years of being shown technology can make amazing advances quickly when conditions are right.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Supersonic air travel has historically used a lot more fuel than subsonic travel. Even if the new crop of supersonic planes is more efficient than the Concorde, it still will use much more fuel than conventional jets. So in trying to reduce CO2 emissions, that will be the major reason supersonic commercial air travel doesn't "take off".
So you just need to scale up the F-22 to carry 100 people!
Big hook in the back of the F-22 and a 100-person capacity glider towed behind. Just get it above supersonic, then release as at that point it's going too fast to slow down before the glider reaches its destination.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
OP did not specify the starting point.
if we can afford to waste it like that.
Being jet-lagged a couple of hours earlier and longer was so much fun.
Drag is really bad from just about Mach 0.8 to about 1.8 or so. That doesn't have anything to do with the engines or anything else you can control. It's a constant known as cD that isn't largely independent of aircraft design.
Meaning you need to cruise at about Mach 2 to have reasonable efficiency in terms of drag.
Supersonic flight isn't just "subsonic flight, but faster". The design of a high speed aircraft is all about how the air flows around the aircraft and through the engines. At Mach 1, which is kinda like "the maximum speed of air", that totally changes. Things work completely differently.
So you have to design your engine for Mach 2, your airframe, etc. All of these will be designed very differently than they would be for subsonic flight. Especially if you intend to fly over land, you're going to need to fly subsonic a significant portion of the time (plus you need to take off and land, and you're not landing at supersonic speeds).
So you have a problem. You need a plane designed to work very well at Mach 2, and it has to be designed to work well subsonic. These are two very different designs. It's hard to have the same plane do well with both. It's kinda like designing an ocean-going ship that's also a bicycle.
Just because there are no people to complain about the sonic boom over the ocean, doesn't mean it's OK. That noise can't be good for whales. I bet the ecological damage would be swept under the rug and the real damage wouldn't be apparent for decades. Hopefully suborbital transportation will make this moot.
TFS does list a handful of the issues with commercial supersonic flight, and I do think that there may be room for those smaller planes. However, supersonic flights have increased competition...
1.) "The cost of three hours". NY to Heathrow is a 7-8 hour flight using standard jets. NY to Heathrow at mach 1.4 is 3-4 hours. If the cost of a ticket is triple, then those three hours have to be worth thousands of dollars *and* there has to be a reason why "fly the day before and book a hotel" isn't practical.
2.) First Class. For the cost of a supersonic flight where every seat is basically a coach seat, passengers can get posh seats that go completely horizontal and get good food and entertainment. A better flight experience can make the 3 hour difference far more tolerable. Concorde didn't have that, and the cost of a first class seat on a supersonic flight would be so exorbitant that it could only be afforded by people who probably have their own private jet anyway.
3.) Telecommuting. Some things still need to be done in person, but Zoom and WebEx have made it possible to have multi-continent, real-time teleconferences. A meeting that would cost a company tens of thousands of dollars to arrange to get everyone in the same room in such a tight timetable that a three hour difference is worth the cost *might* happen once or twice a year, but dozens of teleconferences in between make those cases exceptional at best.
4.) Fuel costs. It takes a LOT more fuel to run a plane at supersonic speeds. Even a small change in fuel costs will drastically impact per-passenger profitability for a flight that's as fuel hungry as supersonic. Yes, planes are lighter now, and yes, this is less of a deal on the smaller planes, but it's still a big deal to airlines, and the tightrope walk between "keeping it profitable" and "keeping the costs low enough to justify using this service over the other options" may very well mean that even a modest bump in fuel costs turns a 1% profit into a 1% deficit.
Commercial supersonic flight is very, very difficult to do profitably.
How many people old enough to afford it can stand the 9Gs necessary
3Gs, not 9.
With good chairs that doesn't seem like much of a stretch.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Travel of any kind follows the same rules of economics as everything else, in that the least expensive thing that meets the wants and needs of the buyer generally wins out. Travel has the added component of wanting to reduce duration as much as practical, but even then, cost wins.
Cost often wins when you consider only convenience - most people are going to be willing to spend nine hours in coach instead of paying $4-5k more for business class.
However note those business class sections are almost always full. Musk has already said suborbital flight costs would be comparable to first-class tickets - For all those flying, do you really not think most of them would spend at least 2x the cost of a first class ticket to get somewhere across the earth in an hour vs. 12 hours (there I am including total travel time including waiting for your craft to depart).
Factor in you would not have to go through the airports we have today, just a small spaceport.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
30 years ago, the main appeal of Concorde (other than the snob value) was the fact that a senior business person was only out of contact with the office for a few hours. Fast forward to nearly-2019 and by the time a new supersonic passenger jet is in the air that advantage will mostly have gone away - With broadband connectivity over the Atlantic, a businessperson will no longer be out of touch from HQ. They can sit in their first class seat, work, make and take calls, send and receive emails, have a couple of glasses of wine and sleep in a lie-flat bed for the same price (or less) than a sardine-seat in a supersonic airliner. I suspect more and more that's where the market will go.
You'd be surprised how often it occurs. I was just finishing up guidance on a project in London a couple of decades ago, and my office called to alert me to an immediate need for me to get to Washington, D.C. I was a Heathrow an hour later to get on the Concorde to JFK (New York), then a charter to D.C. and I made it in about 6 total hours (plus a couple of hours to get to Heathrow).
My client was happy, and we solved the problem in time for the crisis to pass...wouldn't've been even possible without supersonic flight.
(I'll post this as AC, to keep from tooting my own horn.)
Of the super rich. Russians, Arabs, and the CEO's of America. All just have to have a biz jet that can carry the few, the special, the anointed. Remind me again about global warming. Exactly what is the carbon footprint of such a jet. I know a fully loaded 7X7 is a fraction better than a minivan. I'm guessing a 12 passenger supersonic jet, not so great.
Supersonic over the Pacific would still be a game changer. My last 17 hour flight to Singapore was way, way too long. Even in business it's just not fun.
It depends on the price. If it's 1.5 or 2x the cost of a standard economy class ticket, yes it will do very well. If the price is 10 or 20X the cost of a first class seat on a standard airline, no,
Shortest flight from NYC to Sydney I could find was 20 hours. 20 hours vs 30 minutes... You care to revise that prediction at all?
"There is more worth loving than we have strength to love." - Brian Jay Stanley
London-NY subsonic: 7.5 hours
London-NY supersonic: 3.5 hours
Waiting at the check-in desk, checking in, waiting in line at the airport for the security theater, walking the airport's corridors, waiting at the gate, boarding, taxiing, landing, disembarking, walking some more, waiting at the baggage claim, etc: 3 hours if you're lucky. That's assuming flying supersonic isn't reserved for rich fucks who get to fast-track the whole process of course...
Conclusion: if you want people to travel faster, it would make more economic sense to reduce the time it takes *before* and *after* the flying proper.
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
So in trying to reduce CO2 emissions, that will be the major reason supersonic commercial air travel doesn't "take off".
If that were true they would not still be holding climate change conferences where 500 people fly in on 500 private jets.
Those are the same people that would be using the supersonic transport if it were available....
The only question you have to ask when considering if CO2 emissions will be a factor in something not being done is; would it inconvenience the ruling class?
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Call me when suborbital becomes a thing. NY to Australia in 60 minutes.
Seven puppies were harmed during the making of this post.
Supersonic over the Pacific would still be a game changer. My last 17 hour flight to Singapore was way, way too long. Even in business it's just not fun.
If you could have this (Concorde) for 8 hours supersonic -
https://media3.ausbt.com.au/15...
Or this (Singapore Airlines) for 17 hours subsonic (for the same price) -
https://samchui.com/wp-content...
Which would you choose?
Snob value ... like Apple crap ... is sufficient to justify anything. Keeps the riff-raff in place while it succors high-flying success for the ultra-able . I mean ... you can't ( and need not try ) explain servants to a prole.
They can sit in their first class seat, work, make and take calls...
You sure about that?
More seriously, the Concorde replacement or "banker's express" which flies between London City Airport and JFK has explicitly banned phone calls. For obvious reasons:) That flight is the best option currently available for the route and BA has even reused the Concorde flight numbers on it. It's an all Business Class A320 which stops in Ireland on its way Westward because it can't take off from London City Airport's short runway fully fueled and whilst the plane is being refueled the passengers clear US immigration there so that it can land as a domestic flight at JFK. On its return journey it's of course almost empty of fuel and can land on the short runway (being the largest aircraft to do so).
The whole problem with supersonic flight is that it's not efficient. The sonic boom and the aircraft heating up is a sign that you're pushing really hard against the fluid that is the atmosphere. If they can somehow magically eliminate the sonic boom and all the external heating from all that drag then you stand a chance to become more efficient. You need a whole lot more than epic engines to make this work. It's like slapping a truck engine into a small car and claiming that suddenly you can race in Formula 1.
SX, and other launch companies, need the ability to launch constantly. In fact, if SX can launch daily, their costs are around $3M, give or take. So, the BFR/BFS (or whatever the new name is), is being designed to orbital and then land way around the planet. According to numbers by SX, they believe that they can fill BFR with a load of 'first/business' class passengers, fly them from say LA to UK, or LA to Australia/Japan, or Australia to UK, all in under an hour per flight, AND BE PROFITABLE.
SX is making it such that will produce and sell rockets to various airlines and let them compete. Hopefully, Heavies will be used to fly full coach+ from coast to coast at a decent price. Yeah, it will take some 7 hours to go from DC to UK, but, still cheap.
I prefer the "u" in honour as it seems to be missing these days.
Nope. If I can find a flight on a standard airlline for $1k, I sure won't pay 10 or $20k.
The original message I responded to was saying 10-20x the cost of first class tickets.
People today are ALREADY paying almost $10k for business class . They are ALREADY paying up to $30k for really luxurious first class cabins. And those are making money hand over fist and getting plenty of bookings - today.
So now think of all those people who are buying luxury cabins. Are they really doing that because they want to be in an airplane for 20 hours in a small room?
I think the answer will not surprise you: It is an enormous Hell, followed by No.
They want to take 30 minutes to get there, and then be resting in a five star hotel room with full amenities - not a fancy cot on a plane.
I think if SpaceX delivers a flight NYC to almost anywhere on earth in under 30 minutes, a $30k ticket would be sold out for the first year in advance.
People on Slashdot seem to just have no understanding of how truly valuable time is.... they place entirely too much emphasis on the value of money.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Snob value ... like Apple crap ... is sufficient to justify anything.
Not really - If it was, the Concorde would still be flying.
There aren't enough snobs to make a service like Concorde profitable.
If, in the future, airfravt engine parts and fuselages, etc, could be made up of graphene, how much lighter can aircraft get compared to now, with the materials we have now? And what impact would that have on fuel burn, and how much work the engines need to do to push the aircraft?
If you believe in privacy, and believe you have "nothing to hide" at the same time, you're a goddammed idiot
It doesn't really vary much at all with velocity per se (partly because the definition of Cd includes a division by V2 term).
Its pretty much constant from 1 kmh through the entire subsonic regime to over 1,000 kmh. Just below Mach 2 the Cd is right back to its subsonic value and remains constant at hypersonic velocities. It's onlyduring that transition from about Mach 1 to Mach 2 that the suddenly very different behavior of air flows makes it wonky for that particular range.
You are correct that V2 is a very important term, of course.
However, the V2 is divided by V to get the drag per distance, which is what matters for passenger flights. You're trying to get from point A to point B, not trying to fly for one hour. Therefore the V squared term ends up as just V.
This divisiin by V has some very interesting and counterintuitive implications for gliders.
Certainly not with a nose-up attitude :)
Zero pitch would probably be a good idea.
You can land in a nose-down attitude at supersonic speeds, but only once.
* For those unfamiliar, the "attitude" of a plane is which way it is pointing and leaning. (Pitch and roll, and sometimes yaw, depending on context).
Actually, I'd probably go for the supersonic for eight hours.
I understand the argument. You can be comfortable for 17 hours or uncomfortable for 8. In that situation, though, I'd probably take the uncomfortable for 8 over the comfortable for 17.
The main reason, obviously, is that I can sit for eight hours and then lie down in a real bed. Yes, First Class is nice, but it certainly doesn't beat the nice queen-sized hotel bed and I can definitely find restaurants with much better food than what the airline serves.
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I don't see why everybody else needs to give up their sleep just so the super rich can be somewhere a few hours early. For society as a whole, that is actually a really bad trade off.
ITAR is the reason why we never see the F-35 engines in a civilian variant, and the converse is true, you will never see a commercialized TU-160.
The top government officials, at least in Sweden, usually go with regular flights to conferences and meetings. Some travel in 1:st or business class.
There is a government jet also, operated by the Air Force (probably like the US Air force 1?) but it has a quite minor role. On the contrary, several ministers and European MEP:s actually take the train when possible, even internationally within Europe. For example, to the current climate summit in Katowice, Poland.
But yes. I know of several climate researchers that have stopped flying altogether - even when the purpose of the flight is worthwhile. Mostly because they realize how alarming the current situation is. Some system that forced everyone - and especially the richest - to cut down on their flying would be highly appreciated.
No, those are the specifications for Boom. Boom will not meet those specifications, it may meet those specifications.
Just this week there was an item on how Virgin Galactic reached space (or maybe not) with SpaceShipTwo. That program, and all the hype to go with it, has been ongoing for 15 years and they still haven't carried a single commercial passenger.
I wish Boom well, but to claim victory in advance of doing all the work is folly. No one knows if Boom will work out. Especially in the commercial supersonic space.
Remember Concordski (The TU-144)? Remember the L-2000? How about the Boeing 2707? Too long ago? How about the Aerion AS2? How about the Spike S-512?
There is more than a little history and baggage in this space.
How much will the tickets cost to recoup three million dollars every day off of one launch?
Wait until they have at least an inkling of an actual product before you claim how great they are...
You can't even predict the present of even the past accurately.
You lie constantly, why take your predictions about anything seriously?
And you also heard from several people that America's CO2 was going down.
Except it isn't.
Several people also told you China's electricity is 80% coal, and it isn't.
The statement 'people told me' doesn't make something true. The 'people' you speak to, are probably liars just like you...
These have been around for over 50 years too. Bet you've never ridden in one, for the same reason you don't normally eat dinner with a Swiss Army Knife.
https://en.m.wikipedia.org/wik...
This past spring as I flew out of Heathrow the plane taxied by a BA Concorde. I don't know if it is an actual one that flew or a replica but it was very nice to see one final bit of history as we went by.
Or just use common sense and know it isn't practical.