7 ms·

How much fuel does it use, I wonder? Supersonic has been DoA for a while because post-deregulation airlines are only interested in ever more fuel efficient air

How much fuel does it use, I wonder? Supersonic has been DoA for a while because post-deregulation airlines are only interested in ever more fuel efficient aircraft. (It’s also why major states like Japan, China and Russia have for the most part failed to build a competitive airliner against the duopoly.)

lynx23 2y ago
Supersonic is only dead in civil aviation. The military doesn't care about regulations :-)
shiroiushi 2y ago
>It’s also why major states like Japan, China and Russia have for the most part failed to build a competitive airliner against the duopoly. I don't think that has anything to do with it at all. Building a competitive large airliner requires a huge industrial base. And since it's so safety-critical, it takes a lot of time and expertise to build the reputation needed to unseat the incumbents. China has an aircraft manufacturer, but time will tell if it goes anywhere, since they don't exactly have a reputation for high quality. Russia has built many large aircraft in their Soviet days, but their industrial base has eroded so they probably just don't have the capacity to build competitively-priced aircraft in volume now, plus they're not well-liked by most countries that would want airliners anyway. Japan might be able to do it, but just isn't geared up for building lots of large aircraft so it would be a huge investment to build such an industry almost from scratch. Fuel efficiency isn't a factor because building an airliner doesn't involve building engines for that airliner, and engines determine an aircraft's fuel economy for the most part. Boeing and Airbus don't make jet engines: those are all made by Rolls-Royce, Pratt & Whitney, and GE.
- sofixa 2y ago
  > Russia has built many large aircraft in their Soviet days, but their industrial base has eroded so they probably just don't have the capacity to build competitively-priced aircraft in volume now, plus they're not well-liked by most countries that would want airliners anyway Russia did design and build a few designs recently - SSJ-100, MS-21, Tu-204/214. Almost all of them used Western parts (such as engines/avionics) to speed the process up because Russian manufacturers are a few decades behind in some critical parts (like engine efficiency). That being said, they're currently trying to ramp up production on a domestic only Tu-204/214 version, but it's slow, probably quite expensive, and super inefficient. > Japan might be able to do it, but just isn't geared up for building lots of large aircraft so it would be a huge investment to build such an industry almost from scratch. Mitsubishi had a regional jet design in progress, the SpaceJet, which got cancelled after a few billion in R&D and years in delays. Ukraine also had decent manufacturing facilities and capabilities with Antonov and Motor Sich, including decent recent designs and subcontracting work for other companies.. but with the war a lot of things were destroyed (like Antonov and Motor Sich factories and facilities), and their focus is mostly on drones and missiles now. > Fuel efficiency isn't a factor because building an airliner doesn't involve building engines for that airliner, and engines determine an aircraft's fuel economy for the most part. Boeing and Airbus don't make jet engines: those are all made by Rolls-Royce, Pratt & Whitney, and GE. Fuel efficiency is a major factor. Outside of countries big enough to prop up a domestic airliner industry with enough spare cash to compensate for inefficiency (which is a list of 1 country, China), nobody will buy a jet which is less efficient than an alternative. Airline margins are razor thin. And not everyone can buy an engine from Rolls-Royce, GE/CFM(their joint venture with Safran that designs manufactures short-haul engines and the future open fan design) and Pratt and Whitney. The Russian UAC cannot. The Chinese COMAC got sold a decade+ old variant for their latest jet out of fear of industrial espionage (the Chinese engine manufacturers have failed at producing reliable and efficient jet engines for any application, usually relying on Russian designs). TL;DR is that modern airliners are extremely complicated, expensive, and have very long lead times. A new design won't be making any money within the first 10-15 years of its life, which means that only countries with very developed and advanced industrial bases, lots of money, and the desire for strategic airliner autonomy will invest in them.
  - lstodd 2y ago
    well, ssj and ms10/21 were attempts at partially outsourcing, yes. 204/214 are no longer built I think. but the PS90 turbofan is still the mainstay along with D30 derivatives. avionics is a separate question ofc
    - sofixa 2y ago
      > 204/214 are no longer built I think. They are now being built again, because it's the only design that wasn't built with the assumption that Western providers (of avionics, specialised parts, engines) will be available and therefore it's the easiest one to manufacture with an entirely Russian supply chain. Still painful because most of that supply chain is decades old and very rusty, but theoretically possible.
  - shiroiushi 2y ago
    >Fuel efficiency is a major factor. Outside of countries big enough to prop up a domestic airliner industry with enough spare cash to compensate for inefficiency (which is a list of 1 country, China), nobody will buy a jet which is less efficient than an alternative. No, it's not really a factor, because, as I wrote before: airliner manufacturers don't make jet engines. They can only get engine manufacturers to build them engines, and integrate those into their airframe designs. Of course, actually having access to modern, efficient engines is necessary to be competitive, which as you point out is problematic for Russia and China, but if, for instance, a major Japanese company decided to suddenly get into the jumbo-jet business, this shouldn't be an issue for them, provided the existing engine manufacturers have enough manufacturing capacity to provide them engines in addition to those they provide to Airbus/Boeing. So yes, being fuel-efficient is important to the end customers (passenger airline companies), but for the airframe makers, that's really determined by the engines they have access to, not really by any technical capabilities of the aircraft makers. The problem with lack of supply in large passenger jets isn't the engines (AFAIK), it's really just the Boeing/Airbus duopoly and how quickly they can build new aircraft, which use the engines from those suppliers.
    - anovikov 2y ago
whalesalad 2y ago
This is hypersonic. Way faster, way more heat just from moving through air. We will not see passenger aircraft going hypersonic for a long time. It will be hard enough to make a hypersonic aircraft that doesn’t melt itself during flight. The main reason supersonic flight is dead is the sonic boom. Until that issue is resolved they are banned over land, unfortunately.
- af78 2y ago
  | The main reason supersonic flight is dead is the sonic boom Is it? The Concorde would fly at subsonic speeds over land and move to supersonic over the Atlantic. Given the reduced flight time at supersonic speeds I thought economic considerations prevailed.
  - rsynnott 2y ago
    The sonic boom made Concorde's economics harder, but they'd have been hard anyway. It confined it to largely only being useful for that transatlantic route, and that was borderline economically viable for airlines. However, as there was really only one route where it was useful, there were not many Concordes flying and the fixed costs were considerable. Eventually Airbus pulled the plug, and ended maintenance, and that was the end of that. It was probably spurred on by a high-profile disaster, but even without that, the writing was on the wall; if you were an airline Concorde looked economically viable, but without subsidy by the state or by Airbus or both, it never had been. In a world where there had been many viable Concorde routes, this could all have worked out a lot differently, Concorde B might have happened (which would have allowed a Pacific crossing), and maybe we'd still see supersonic airliners.
    - lstodd 2y ago
      This I agree with. There were not enough viable routes. Same thing happened with TU-144 - no destinations.
      - twelve40 2y ago
15155 2y ago
Cruise missiles have different efficiency goals than commercial airliners.
Beretta_Vexee 2y ago
It's a hypersonic thruster, i.e. 5 or more times the speed of sound. Far too fast for civil aviation. It's probably even too fast for "safe" manned flight. This is the speed at which the air ionizes around the vehicle. It's like flying inside a fireball. The first use that comes to mind is a hypersonic cruise missile or unmanned bomber. Intercontinental missiles are also hypersonic, but their re-entry vehicles are gliders with limited maneuvering capabilities. The Russians have developed and used hypersonic air-to-ground missiles in Ukraine, the Kinzhal. It is very difficult to intercept a missile at these speeds, and almost impossible if the missile is maneuverable. This has re-launched research into this type of missile and propulsion system. Russia is ahead in this field. The USA, China and France have carried out various experiments (mach 5 to 25), but do not really have combat-ready hypersonic weapons. One of the great difficulties of hypersonic flight is that you generally need one engine and one stage per flight regime. The majority of demonstrators operate according to the following scheme: - a rocket or aircraft propels the vehicle to supersonic speed, so that it can start its engine. - The vehicle accelerates to Mach 5. The vehicle starts its hypersonic engine and detaches from the supersonic stage. - Climb to the edge of space. - Descent and acceleration. - Detachment from the hypersonic engine and final gliding approach. The fireball moving off at mach 20 kind of approch. The engine shown here would enable to have just one engine for supersonic and hypersonic flight, greatly simplifying the vehicle. The fact that it's an engine and not a rocket is important, as it means that the thrust is much longer and can potentially last for the whole flight. At these speeds, it's largely the engine's thrust that makes maneuvering possible, and this is what distinguishes these vehicles from the hypersonic glider/reentry vehicle found on intercontinental missiles.
- dralley 2y ago
  If you define "hypersonic weapon" as merely traveling at or beyond Mach 5, then practically every medium range ballistic missile since the V-2 qualifies. There is nothing special about a missile that can hit hypersonic speeds. The real difference is maneuvering, but most of Russia's "hypersonic weapons" cannot actually do this. Hence why Ukraine has shot down nearly every Khinzal that has been fired at Kyiv and about half of the Zircon missiles too, using technology that has existed for decades. IIRC one of the Khinzal missiles was even knocked out by a PAC-2 missile, which wasn't designed for that purpose. Maybe AvanGuard is more competent and less overrated/overhyped than their other efforts, but there's no particularly good reason to believe that. Meanwhile the last time the US successfully tested a hypersonic weapon it was immediately greenlit for serial production, and I don't think that's because they are freaking out so much as that the US sandbags our capabilities while some of our competitors inflate theirs. You claim the Russians are ahead, but they keep putting their hypersonic engine researchers in jail. I don't buy it.
dghughes 2y ago
Half for a cheeky answer. The air is part of the fuel and onboard fuel hydrogen or some other thing to burn is the other half. Really at >Mach 5 you'll be there fast. At Mach 5 NY to London in 54 min. Mach 10 it's 12 minutes.
GartzenDeHaes 2y ago
> which could enable high-speed flight and longer range across numerous multi-mission aircraft This is DoD language, so more secret drones I would think.
thrillgore 2y ago
People are forgetting why they are really building this hypersonic rocket: Nuclear stockpile.
- 15155 2y ago
  Why would you not just use a ballistic missile for nuclear delivery? What advantage does an air-breathing engine have in this capacity over MIRVs and decoys?
  - thrillgore 2y ago
    Hypersonic missiles can defeat current defense systems (based on available intelligence)
dotnet00 2y ago
Supersonic has also been dead because passenger supersonic flight is banned over the continental US (and probably similar restrictions exist in Europe). In the US the regulations will be getting reviewed depending on the results of studies on building supersonic jets that make less noise (after which it'd be down to if they can be made efficient enough to be profitable).
kevin_thibedeau 2y ago
You don't need to make an airliner. There are enough billionaires in the world to support a small industry of supersonic private jets. All of the marketing hype about supersonic for the masses is a figleaf to avoid being pilloried over tech that only serves the ultra wealthy.

lynx23 2y ago

Supersonic is only dead in civil aviation. The military doesn't care about regulations :-)

shiroiushi 2y ago

>It’s also why major states like Japan, China and Russia have for the most part failed to build a competitive airliner against the duopoly. I don't think that has anything to do with it at all. Building a competitive large airliner requires a huge industrial base. And since it's so safety-critical, it takes a lot of time and expertise to build the reputation needed to unseat the incumbents. China has an aircraft manufacturer, but time will tell if it goes anywhere, since they don't exactly have a reputation for high quality. Russia has built many large aircraft in their Soviet days, but their industrial base has eroded so they probably just don't have the capacity to build competitively-priced aircraft in volume now, plus they're not well-liked by most countries that would want airliners anyway. Japan might be able to do it, but just isn't geared up for building lots of large aircraft so it would be a huge investment to build such an industry almost from scratch. Fuel efficiency isn't a factor because building an airliner doesn't involve building engines for that airliner, and engines determine an aircraft's fuel economy for the most part. Boeing and Airbus don't make jet engines: those are all made by Rolls-Royce, Pratt & Whitney, and GE.

sofixa 2y ago
> Russia has built many large aircraft in their Soviet days, but their industrial base has eroded so they probably just don't have the capacity to build competitively-priced aircraft in volume now, plus they're not well-liked by most countries that would want airliners anyway Russia did design and build a few designs recently - SSJ-100, MS-21, Tu-204/214. Almost all of them used Western parts (such as engines/avionics) to speed the process up because Russian manufacturers are a few decades behind in some critical parts (like engine efficiency). That being said, they're currently trying to ramp up production on a domestic only Tu-204/214 version, but it's slow, probably quite expensive, and super inefficient. > Japan might be able to do it, but just isn't geared up for building lots of large aircraft so it would be a huge investment to build such an industry almost from scratch. Mitsubishi had a regional jet design in progress, the SpaceJet, which got cancelled after a few billion in R&D and years in delays. Ukraine also had decent manufacturing facilities and capabilities with Antonov and Motor Sich, including decent recent designs and subcontracting work for other companies.. but with the war a lot of things were destroyed (like Antonov and Motor Sich factories and facilities), and their focus is mostly on drones and missiles now. > Fuel efficiency isn't a factor because building an airliner doesn't involve building engines for that airliner, and engines determine an aircraft's fuel economy for the most part. Boeing and Airbus don't make jet engines: those are all made by Rolls-Royce, Pratt & Whitney, and GE. Fuel efficiency is a major factor. Outside of countries big enough to prop up a domestic airliner industry with enough spare cash to compensate for inefficiency (which is a list of 1 country, China), nobody will buy a jet which is less efficient than an alternative. Airline margins are razor thin. And not everyone can buy an engine from Rolls-Royce, GE/CFM(their joint venture with Safran that designs manufactures short-haul engines and the future open fan design) and Pratt and Whitney. The Russian UAC cannot. The Chinese COMAC got sold a decade+ old variant for their latest jet out of fear of industrial espionage (the Chinese engine manufacturers have failed at producing reliable and efficient jet engines for any application, usually relying on Russian designs). TL;DR is that modern airliners are extremely complicated, expensive, and have very long lead times. A new design won't be making any money within the first 10-15 years of its life, which means that only countries with very developed and advanced industrial bases, lots of money, and the desire for strategic airliner autonomy will invest in them.
- lstodd 2y ago
  well, ssj and ms10/21 were attempts at partially outsourcing, yes. 204/214 are no longer built I think. but the PS90 turbofan is still the mainstay along with D30 derivatives. avionics is a separate question ofc
  - sofixa 2y ago
    > 204/214 are no longer built I think. They are now being built again, because it's the only design that wasn't built with the assumption that Western providers (of avionics, specialised parts, engines) will be available and therefore it's the easiest one to manufacture with an entirely Russian supply chain. Still painful because most of that supply chain is decades old and very rusty, but theoretically possible.
- shiroiushi 2y ago
  >Fuel efficiency is a major factor. Outside of countries big enough to prop up a domestic airliner industry with enough spare cash to compensate for inefficiency (which is a list of 1 country, China), nobody will buy a jet which is less efficient than an alternative. No, it's not really a factor, because, as I wrote before: airliner manufacturers don't make jet engines. They can only get engine manufacturers to build them engines, and integrate those into their airframe designs. Of course, actually having access to modern, efficient engines is necessary to be competitive, which as you point out is problematic for Russia and China, but if, for instance, a major Japanese company decided to suddenly get into the jumbo-jet business, this shouldn't be an issue for them, provided the existing engine manufacturers have enough manufacturing capacity to provide them engines in addition to those they provide to Airbus/Boeing. So yes, being fuel-efficient is important to the end customers (passenger airline companies), but for the airframe makers, that's really determined by the engines they have access to, not really by any technical capabilities of the aircraft makers. The problem with lack of supply in large passenger jets isn't the engines (AFAIK), it's really just the Boeing/Airbus duopoly and how quickly they can build new aircraft, which use the engines from those suppliers.
  - anovikov 2y ago

whalesalad 2y ago

This is hypersonic. Way faster, way more heat just from moving through air. We will not see passenger aircraft going hypersonic for a long time. It will be hard enough to make a hypersonic aircraft that doesn’t melt itself during flight. The main reason supersonic flight is dead is the sonic boom. Until that issue is resolved they are banned over land, unfortunately.

af78 2y ago
| The main reason supersonic flight is dead is the sonic boom Is it? The Concorde would fly at subsonic speeds over land and move to supersonic over the Atlantic. Given the reduced flight time at supersonic speeds I thought economic considerations prevailed.
- rsynnott 2y ago
  The sonic boom made Concorde's economics harder, but they'd have been hard anyway. It confined it to largely only being useful for that transatlantic route, and that was borderline economically viable for airlines. However, as there was really only one route where it was useful, there were not many Concordes flying and the fixed costs were considerable. Eventually Airbus pulled the plug, and ended maintenance, and that was the end of that. It was probably spurred on by a high-profile disaster, but even without that, the writing was on the wall; if you were an airline Concorde looked economically viable, but without subsidy by the state or by Airbus or both, it never had been. In a world where there had been many viable Concorde routes, this could all have worked out a lot differently, Concorde B might have happened (which would have allowed a Pacific crossing), and maybe we'd still see supersonic airliners.
  - lstodd 2y ago
    This I agree with. There were not enough viable routes. Same thing happened with TU-144 - no destinations.
    - twelve40 2y ago

15155 2y ago

Cruise missiles have different efficiency goals than commercial airliners.

Beretta_Vexee 2y ago

It's a hypersonic thruster, i.e. 5 or more times the speed of sound. Far too fast for civil aviation. It's probably even too fast for "safe" manned flight. This is the speed at which the air ionizes around the vehicle. It's like flying inside a fireball. The first use that comes to mind is a hypersonic cruise missile or unmanned bomber. Intercontinental missiles are also hypersonic, but their re-entry vehicles are gliders with limited maneuvering capabilities. The Russians have developed and used hypersonic air-to-ground missiles in Ukraine, the Kinzhal. It is very difficult to intercept a missile at these speeds, and almost impossible if the missile is maneuverable. This has re-launched research into this type of missile and propulsion system. Russia is ahead in this field. The USA, China and France have carried out various experiments (mach 5 to 25), but do not really have combat-ready hypersonic weapons. One of the great difficulties of hypersonic flight is that you generally need one engine and one stage per flight regime. The majority of demonstrators operate according to the following scheme: - a rocket or aircraft propels the vehicle to supersonic speed, so that it can start its engine. - The vehicle accelerates to Mach 5. The vehicle starts its hypersonic engine and detaches from the supersonic stage. - Climb to the edge of space. - Descent and acceleration. - Detachment from the hypersonic engine and final gliding approach. The fireball moving off at mach 20 kind of approch. The engine shown here would enable to have just one engine for supersonic and hypersonic flight, greatly simplifying the vehicle. The fact that it's an engine and not a rocket is important, as it means that the thrust is much longer and can potentially last for the whole flight. At these speeds, it's largely the engine's thrust that makes maneuvering possible, and this is what distinguishes these vehicles from the hypersonic glider/reentry vehicle found on intercontinental missiles.

dralley 2y ago
If you define "hypersonic weapon" as merely traveling at or beyond Mach 5, then practically every medium range ballistic missile since the V-2 qualifies. There is nothing special about a missile that can hit hypersonic speeds. The real difference is maneuvering, but most of Russia's "hypersonic weapons" cannot actually do this. Hence why Ukraine has shot down nearly every Khinzal that has been fired at Kyiv and about half of the Zircon missiles too, using technology that has existed for decades. IIRC one of the Khinzal missiles was even knocked out by a PAC-2 missile, which wasn't designed for that purpose. Maybe AvanGuard is more competent and less overrated/overhyped than their other efforts, but there's no particularly good reason to believe that. Meanwhile the last time the US successfully tested a hypersonic weapon it was immediately greenlit for serial production, and I don't think that's because they are freaking out so much as that the US sandbags our capabilities while some of our competitors inflate theirs. You claim the Russians are ahead, but they keep putting their hypersonic engine researchers in jail. I don't buy it.

dghughes 2y ago

Half for a cheeky answer. The air is part of the fuel and onboard fuel hydrogen or some other thing to burn is the other half. Really at >Mach 5 you'll be there fast. At Mach 5 NY to London in 54 min. Mach 10 it's 12 minutes.

GartzenDeHaes 2y ago

> which could enable high-speed flight and longer range across numerous multi-mission aircraft This is DoD language, so more secret drones I would think.

thrillgore 2y ago

People are forgetting why they are really building this hypersonic rocket: Nuclear stockpile.

15155 2y ago
Why would you not just use a ballistic missile for nuclear delivery? What advantage does an air-breathing engine have in this capacity over MIRVs and decoys?
- thrillgore 2y ago
  Hypersonic missiles can defeat current defense systems (based on available intelligence)

dotnet00 2y ago

Supersonic has also been dead because passenger supersonic flight is banned over the continental US (and probably similar restrictions exist in Europe). In the US the regulations will be getting reviewed depending on the results of studies on building supersonic jets that make less noise (after which it'd be down to if they can be made efficient enough to be profitable).

kevin_thibedeau 2y ago

You don't need to make an airliner. There are enough billionaires in the world to support a small industry of supersonic private jets. All of the marketing hype about supersonic for the masses is a figleaf to avoid being pilloried over tech that only serves the ultra wealthy.