Vai al contenuto

Jet executive supersonici


Ospite intruder

Messaggi raccomandati

  • 3 settimane dopo...
  • 1 mese dopo...

Nuovi studi di Boeing ...

Quote

Boeing Studies Morphing Low-Boom SST ...
Graham Warwick - AW&ST - 14 Jan. 2019

Progress has been made in designing supersonic aircraft to minimize sonic boom, and Lockheed Martin is building a flight demonstrator for NASA, the X-59A QueSST, that aims to achieve a muted boom of around 75 PNLdB, compared with 110 PNLdB for the Concorde. 
The reduced noise level is achieved by shaping the airframe to modify the sonic-boom signature. 
This prevents shockwaves from the aircraft coalescing as they propagate through the atmosphere into strong bow and aft shocks that form an N-wave signature and produce the classic “double-bang” boom. 
Shaped signatures are sinusoidal and create a sonic “thump” rather than a boom. 
But the airframe shape is optimized for the design cruise condition, and off-design, when operating at a different Mach number of angle of attack (AOA), the boom signature will change. 
In a low-boom design, there are airframe-shaping features that would look abnormal on a subsonic aircraft but are critical to controlling the shockwaves and preventing them coalescing. 
In designs such as the X-59, these bumps are fixed.

TECHWEEK03_3_Boeing.jpg
Analysis indicates that a shape-memory morphing surface under the nose could make the forward part of a low sonic boom more robust. 
Credit: Boeing

Boeing is investigating whether shape-memory alloys (SMA) could be used to change the outer mold line (OML) of the aircraft, actively altering local surface geometry to make a low-boom design more robust over a wider range of operating conditions. 
“OML shapes matter and flight conditions matter, and low-boom aircraft are optimized for a specific cruise condition,” Boeing engineer David Lazzara said at the SciTech conference. 
“We are looking at SMA actuation to morph the surface and move away from a constant, single OML.” 
Using NASA’s 25D low-boom configuration, Boeing led work to investigate off-design performance and identify where morphing surfaces could be located to make the design more robust. 
The team assessed the boom at different perturbations of Mach number and AOA away from the design point. 
“Off-design, most of the time the boom will degrade,” says Lazzara. 
“And small changes can have a pronounced impact on the boom at ground level. Analysis showed that Mach perturbations have the most effect on the forward half of the boom signature and AOA changes on the aft half.” 
“This helped us choose which part of the vehicle to look at,” he says. 
The areas on the signature that had the highest sensitivity turned out to be under the nose and a broad area under the rear of the wing and around the overwing engine inlet. 
Further optimization work is planned. 
The project is being conducted under NASA’s University Leadership Initiative program. 
Boeing’s partners include Texas A & M University, Utah State University, Florida International University, University of Houston, University of North Texas, Princeton University, ATA Engineering and Fort Wayne Metals.

 

Link al commento
Condividi su altri siti

Interessante che finalmente si parli dell'applicazione di materiali capaci di modificare la loro forma. Se vogliamo, tutti gli attuali sistemi atti a modificare la geometria di un velivolo, (applicati magari alla sola ala) sono delle approssimazioni discrete e grossolane delle forme ideali che dovrebbe avere una superficie al variare delle condizioni al contorno.

Link al commento
Condividi su altri siti

  • 3 settimane dopo...

E meno male che Aerion prima aveva come partner Lockheed Martin e prima ancora Airbus...

https://www.flightglobal.com/news/articles/lockheed-and-aerion-to-develop-supersonic-business-j-444243/

Aerion se li sta ripassando tutti... Ora è approdata a Boeing, che in teoria, come visto sopra, col suo trasporto ipersonico stava pensando (si spera ancora lo stia facendo...) a qualcosa di un tantino più spinto di questo brutto anatroccolo timotore...

A giugno scrivevo questo...

Quote

Vediamo quindi se il futuro ci riserverà un supersonico "tranquillo e smart" (magari un po' più smart dell'Aerion...) e/o se Boeing porterà in porto questo concetto ardito (siamo ben lontani da un progetto), superando le naturali ritrosie di un mondo dell’aviazione tremendamente ancorato al passato, mentre i suoi utenti vengono rimbambiti da sempre nuovi smartphone con cui però possono prenotare voli che durano un’eternità, mentre sono comodamente sbragati sul divano di casa e dopo aver scritto qualche inutile boiata su facebook o su whatsapp.

Ecco...appunto...

Link al commento
Condividi su altri siti

5 ore fa, TT-1 Pinto ha scritto:

Non so il perché ma il tweet di Aerion è scomparso ...

Provo a riproporlo ... è una semplice curiosità per vedere cosa succede ... spero che Flaggy non mi fustighi ... :sm:

 

 

 

Link al commento
Condividi su altri siti

  • 3 settimane dopo...

Un articolo interessante che spiega la filosofia alla base del trimotore AS2 di Aerion +Boeing.

https://aviationweek.com/business-aviation/supersonic-aircraft-developers-tackle-environmental-challenges

Il velivolo non punta a un bang sonico attutito grazie a una apposita configurazione aerodinamica come quella in studio presso la NASA (giudicata non matura e comunque pesante in rapporto ai volumi di cabina garantiti). Più che altro il bang sarebbe limitato dalla velocità contenuta a mach 1.4 e dalle minori dimensioni rispetto al Concorde.

Non si punta nemmeno a far rimuovere il bando al volo supersonico su terra, almeno non certo con un progetto dichiaratamente non particolarmente spinto come l’AS2.

Su terra si punta proprio da eliminare il bang sonico volando in subsonico o sfruttando un trucco volando ad alta quota a velocità blandamente supersoniche (mach 1.2) che al suolo, dove l’aria è più densa e calda e la velocità del suono è maggiore, corrispondono a velocità subsoniche (la velocità del suono e massima al suolo e cala in quota).

In tal modo le onde d’urto prodotte ad alta quota non riescono a propagarsi alle quote più basse, ma vengono ridirette verso l’alto, di fatto eliminando il bang sonico e lasciando che solo un “normale” rumore giunga al suolo.

SUPERSONICNEXT_diagram.jpg

Link al commento
Condividi su altri siti

  • 2 settimane dopo...
  • 3 mesi dopo...

Da Parigi ... il dimostratore XB-1 di Boom Technology effettuerà il suo primo volo con alcuni mesi di ritardo ... 

Quote

Boom Technology has pushed the first flight of its XB-1 demonstrator back to 2020, as it works with Japan Airlines on its planned Overture airliner.
Boom chief executive Brett Scholl says the XB-1 – which is one-third the size of the Overture – will be rolled out in December 2019, about six months later than previously planned. 
He attributed the decision to a safety enhancement.
"Whenever it comes to safety and schedule, safety comes first," he says. 
"Earlier this year, we found there was an opportunity to enhance the safety profile of the [XB-1] aircraft by including a stability augmentation system, to give us additional margin at high speed and at take-off and landing."

... flightglobal.com ... PARIS: Boom XB-1 schedule slips, while JAL eyes Overture ...

Link al commento
Condividi su altri siti

"Si torni ad attraversare l'Atlantico in tre ore!"
E' un'esortazione che viene dagli ambienti presidenziali USA ...

Michael Kratsios is deputy assistant to the president for technology policy at the White House and President Trump’s nominee for chief technology officer of the United States.

Quote

Fifty years ago, the first Concorde prototype roared over the 28th International Paris Air Show, initiating a supersonic era that enabled flight from New York to London in just over three hours. 
Four years later, in 1973 — only 70 years after the Wright brothers first took to the skies — the Concorde made its debut transatlantic journey.
This exciting era of civil supersonic flight, however, would last only 30 years. 
Supersonic flight has largely remained dormant since the Concorde’s final flight in 2003. 
Today, that same New York-to-London flight takes about seven hours. 
While technology flourished since 1973, we’re still traveling by air at about the same speeds that we were before landing men on the moon.
Fortunately, we are now seeing a change in course.

... washingtonpost.com ... We used to fly from New York to Paris in 3 hours. Let’s do that again ...

Link al commento
Condividi su altri siti

E c'è anche LM ...

Quote

Lockheed Martin is considering how to build a commercial supersonic aircraft that would draw on the noise-reduction technology it is testing with NASA, making it the latest company aiming to create a market for travel faster-than-sound travel.
The quiet supersonic technology airliner (QSTA) concept Lockheed Martin announced on 19 June at the American Institute of Aeronautics and Astronautics Aviation Forum is still at the beginning of the design process.
The Skunk Works division of Lockheed Martin in Palmdale, California is building the X-59 test aircraft for NASA in a separate project. 
The QTSA would be larger than the X-plane with capacity for 40 people, measuring 69m (225ft) long with a 22m wingspan.

... flightglobal.com ... Lockheed Martin adds momentum for supersonic travel ...

Link al commento
Condividi su altri siti

  • 5 mesi dopo...

Giusto due anni fa si disquisiva del passaggio dalla configurazione con due vetusti JT8D a tre derivati del CFM56. Ora questo motore con un nuovo modulo a bassa pressione sappiamo che si chiama Affinity.

https://www.geaviation.com/bga/engines/ge-affinity

https://en.wikipedia.org/wiki/General_Electric_Affinity

affinity-3.4-2018.jpg

Il CFM56 è stato ed è un motore indiscutibilmente di successo. Molto usato su A320 e B737 è a sua volta un derivato ad alto rapporto di diluizione (6:1) dell’F101 montato sul bombardiere B-1 (BPR poco inferiore a 2), che ha avuto anche un derivato piuttosto noto a basso BPR nell’F110 montato in varie versioni sull’F-16 e su altri caccia (con un BPR intorno a 0.7-0.8).

Gira e rigira quindi il core ad alta pressone è lo stesso.  Non si può non notare che il CFM56 in ambito civile trova oggi il suo sostituto nel LEAP che ha un core ad altra pressone riprogettato e un rapporto di diluizione più alto per consumare meno in subsonico, mentre nell’Affinity il core è sempre quello del CFM56 e il rapporto di diluizione scende a 3, non molto più alto di quello dell’originario F101 e il tutto si paga con un consumo specifico che sale del 50%.

Insomma, su un aereo che trasporta una dozzina di persone a mach 1.4 ci sono 3 motori con un consumo specifico il 50% in più alto dei due con cui i liner civili portano a spasso 200 persone. Se non altro quei 3 motori consumano di più ma per meno tempo visto che il volo dura meno...

Diciamocelo chiaramente però: non è certo l’aereo con cui il signor Rossi andrà in vacanza o al lavoro…e quindi siamo ancora ben lontani da un deciso passo avanti nel trasporto di massa.

 

 

 

Modificato da Flaggy
Link al commento
Condividi su altri siti

  • 3 mesi dopo...
  • 3 settimane dopo...

Anche Aerion Supersonic fa le sue mosse ...

Quote

With an eye on bringing a civil supersonic business jet to market around the 2026 timeframe, Aerion Supersonic is laying the groundwork to shift from a design firm to a manufacturer with the selection of Melbourne, Florida, as the site of its new factory and the firming up of a final design of the aircraft. 
Aerion in late April announced it would break ground later this year on a $300 million facility at Florida’s Melbourne International Airport (MLB) to serve as the home for production of its Mach 1.4, 12-place AS2 trijet.
This announcement came as Aerion firmed up what the company believes is the final design configuration for the airplane, adopting a new look that sports a delta-shaped wing, revamped empennage, and new elongated nacelle shape that Aerion said incorporates new materials and technologies, yet provides a design that could ensure the business jet meets timeline and production requirements.

... ainonline.com ... Aerion Paving Path To Bring AS2 to Market ...

??

Link al commento
Condividi su altri siti

GE Aviation comunica ...

Quote

GE Aviation has now officially shipped its first engine for NASA’s X-59 QueSST (short for Quiet SuperSonic Technology), an experimental piloted aircraft designed to fly faster than sound, cruise at 55,000 feet yet generate significantly less noise than previous supersonic aircraft such as the SST or Concorde.

... blog.geaviation.com ... QueSST for Success: Fly in Half the Time ...

??

Link al commento
Condividi su altri siti

  • 3 settimane dopo...

Intanto ... vi sono quesiti per i quali si attende una risposta ... ma non prima del prossimo anno ...

Quote

Despite the use of advanced design tools, the team developing NASA’s X-59 Quiet Supersonic Technology (QueSST) demonstrator cannot be sure it will meet their “low-boom” goals until the jet actually breaks the sound barrier in flight. 
Although design features that reduce sonic booms are understood, the team faces the challenge of ensuring that the X-59 QueSST retains its unique boom-softening shape while in flight. 
It is also unclear how sound from the jet will move through the atmosphere.
Those questions will be answered through flight testing, which the team expects will begin in autumn 2021.
“When you get a real aircraft in a real atmosphere, there’s a lot of variables that are difficult to model,” says Craig Nickol, manager of NASA’s Low-Boom Flight Demonstrator project, the effort behind X-59. 
“How that signature propagates through the atmosphere becomes difficult to predict.” 
But Nickol and partners at Lockheed Martin think the X-59 will prove that supersonic aircraft can have acceptably soft booms, possibly leading to a supersonic air travel renaissance.

... flightglobal.com ... NASA and Lockheed to begin X-59 supersonic jet tests in 2021 ...

??

Link al commento
Condividi su altri siti

  • 2 settimane dopo...

Motore Affinity ... GE Aviation rivela qualche dettaglio ...

Quote

GE Aviation this week provided a glimpse into design challenges that the company is working through as it progresses on the twin-shaft, medium-bypass Affinity engine selected to power the  Aerion AS2 supersonic business jet. 
Aerion Supersonic and GE announced plans in October 2018 to move forward with the Affinity for the AS2, saying it would be designed using a “proven engine core adapted from GE’s commercial airline portfolio” with the latest technology full authority digital engine control, an advanced twin-fan, durable combustor, and advanced acoustic technology that would meet or exceed regulatory requirements.
While GE has not specified beyond saying the engine pulls from its commercial engine core expertise, it is believed to borrow from the CFM56. 
But GE does say the Affinity adopts features from its new Passport business jet engine such as the front fan blisks and slimline composite core ducting.
Anticipated to be part of a family in the 16,000- to 20,000-pound-thrust range, the Affinity will be certified to operate at altitudes up to 60,000 feet and capable of providing efficient super and subsonic transport.

... ainonline.com ... GE Tackling Environmental Challenges with Affinity Engine ...

... geaviation.com ... The Affinity Supersonic turbofan ...

??

Link al commento
Condividi su altri siti

Arrivano i Russi ...

Russian researchers start drawing up new supersonic jet concept ...

By David Kaminski-Morrow (22 June 2020)

Russian researchers have embarked on preliminary investigations into development of a civil supersonic aircraft, nearly four decades after the Tupolev Tu-144 programme ended.
The work is being undertaken by the Zhukovsky Institute, a federal collective national research organisation which includes several centres – among them the Central Aerohydrodynamic Institute, the Central Institute of Aviation Motors, and the Siberian Aeronautical Research Institute.
This organisation has been established to co-ordinate research into new developments and technologies in the aviation sector.

70913_zhukovskysst_740685.jpg
Source: Zhukovsky Institute
While a formal design has yet to be revealed, this concept has been floated

Director general Andrei Dutov says the creation of a commercially-successful supersonic aircraft is a “big challenge” for the industry.
“It is necessary to find effective solutions to the problems of high levels of noise and sonic shock, increase the fuel efficiency of powerplants, and reduce harmful emissions,” he says.
“It’s too early to talk about the cost of the new aircraft. But it will, of course, be more expensive than its subsonic counterparts.”
Dutov says the intention is to draw up a concept and a comprehensive programme for creating the aircraft, including gathering scientific and technical resources, enabling manufacturers to start technical design work as early as 2022.
The preliminary research is part of a state contract reached with the Russian trade and industry ministry running to the end of 2021.
Few details of the proposed aircraft have emerged, but initial illustrations indicate twin-tailed configurations with centrally-mounted engines are being examined.
Dutov says the aircraft would need to cruise at some 1,100kt (2,000km/h), else it would have few advantages over subsonic designs.
As well as leading to the emergence of new technologies, the institute suggests a business version of the aircraft, with fewer passengers, would open new markets.
Crucial to the development of a supersonic aircraft would be efforts to mitigate noise while overflying populated areas – an issue which plagued the Aerospatiale-BAC Concorde programme – and this could require trade-off with the aerodynamic design.
New engine development, combining high thrust with economic efficiency, will be necessary.
US firm Aerion has been developing its own supersonic civil aircraft, the AS2, which it has been aiming to fly by 2024. 
The manufacturer claims it has developed a technology enabling a “boomless cruise”, enabling it to fly without creating a sonic boom.
Another US developer, Boom Supersonic, has also been progressing with its own supersonic airliner design, designated Overture, with a demonstrator programme known as the XB-1. 
The aircraft has a low-mounted delta-wing configuration, in contrast to the high-wing layout of the AS2.

Fonte: FlightGlobal ...

??

Link al commento
Condividi su altri siti

  • 1 mese dopo...

"Overture" ... potrebbe sembrare musica lirica ... ma non lo è ...

72046_cruise60k_12_581779.jpg

Quote

Boom Supersonic and Rolls-Royce have entered into a so-called engagement agreement to explore the pairing of a Rolls-Royce propulsion system with Boom's proposed supersonic passenger aircraft called Overture, the companies announced Thursday.
In a statement (*), Boom said the agreement calls for the companies to work together to identify the propulsion system that would complement Boom's Overture airframe. 
Apart from studies associated with matching the engine and airframe, the teams will also examine certain “key” aspects of the propulsion system, the statement said.

 ... ainonline.com ... Boom, Rolls-Royce Ink Overture Collaboration Pact ...

(*) ... Boom Supersonic and Rolls-Royce Agree on New Collaboration for Supersonic Overture Engine Program + Design ...

?? + ??

 

Link al commento
Condividi su altri siti

Il dimostratore sperimentale supersonico X-59 della NASA sarà sprovvisto di finestrino frontale ...

Quote

In addition to testing sound signatures of new supersonic airplanes, NASA’s X-59 Quiet Supersonic Technology (QueSST) experimental demonstrator is breaking ground in another area: flight without a forward-facing window.
The NASA/Lockheed Martin X-plane will come with an eXternal Vision System (XVS) in lieu of a forward-facing window. 
The technology already has been tested in NASA’s Beechcraft King Air UC-12B (*) in preparation for the X-59’s first flight in 2021.
XVS uses real-time imagery from two externally mounted cameras that are overlayed with terrain data on a 4K monitor in front of the pilot, NASA said.

... ainonline.com ... NASA X-Plane Provides New Vision ...

(*) ... nasa.gov ... Testing of X-59 Virtual Forward Window Successful ...

??

Link al commento
Condividi su altri siti

Crea un account o accedi per lasciare un commento

Devi essere un membro per lasciare un commento

Crea un account

Iscriviti per un nuovo account nella nostra community. È facile!

Registra un nuovo account

Accedi

Sei già registrato? Accedi qui.

Accedi Ora
×
×
  • Crea Nuovo...