Naves Aeroespaciales Reutilizables -Japón


 

En 2021. 29 de mayo. Una hoja de ruta presentada en un panel de expertos a principios del mes de mayo fue anunciada por el Ministerio de Ciencia del país donde se planea desarrollar naves espaciales intercontinentales de pasajeros para principios de la década de 2040, en un plan de 2 fases, donde con la ayuda de empresas privadas, se prevén dos tipos diferentes de naves espaciales:
-un avión espacial similar a un transbordador que pueda aterrizar en una pista como un avión normal, y
-un avión espacial que aterrice verticalmente como los cohetes reutilizables de SpaceX.
La hoja de ruta igualmente prevé tácticas como la reutilización de piezas de cohetes les permitirán reducir ese costo a la mitad para 2030, y bajarlo hasta el 10% a principios de la década de 2040.
La idea es utilizar un sistema similar a los misiles balísticos intercontinentales: usar un cohete para lanzar la carga útil, en este caso una nave espacial de pasajeros, hacia el espacio para que vuelva a entrar en la atmósfera al otro lado del planeta.
El cohete H3 de nueva generación del país, cuyo vuelo inaugural está previsto para el mismo año 2021, cuesta aproximadamente 5.000 millones de yenes (USD 46 millones).

 

 

*Hay que considerar muy importante que los humanos simplemente no están hechos para el tipo de aceleración y fuerza G que sufre un misil balístico intercontinental, y podrían morir fácilmente en el lanzamiento o la reentrada.
 
 
[Recuperados]
Naves Aeroespaciales Reutilizables

Una estela de luz dejada por un cohete H2B brilla sobre el monte Sakurajima en Kagoshima, al suroeste de Japón, en esta foto de larga exposición tomada por Kyodo el 21 de mayo de 2020. Crédito obligatorio Kyodo/vía REUTERS
El auge de la industria espacial facilita más que nunca la puesta en órbita, pero Japón apuesta por revolucionar también los viajes terrestres. El Ministerio de Ciencia del país anunció que planea desarrollar naves espaciales intercontinentales de pasajeros para principios de la década de 2040.
La idea de utilizar naves espaciales para viajar de un punto a otro de la superficie terrestre existe desde hace décadas, pero el costo y la complejidad de la idea vienen postergando el sueño de manera sistemática. Ahora Japón cree que puede lograrlo.
En la práctica, advierten los especialistas, la idea es utilizar un sistema similar a los misiles balísticos intercontinentales: usar un cohete para lanzar la carga útil, en este caso una nave espacial de pasajeros, hacia el espacio para que vuelva a entrar en la atmósfera al otro lado del planeta.
Según detalla la web especializada Singularityhub, este método podría permitir viajar entre continentes en menos de una hora, y ahora Japón ha esbozado su visión de cómo hacer realidad la idea. En una hoja de ruta presentada en un panel de expertos a principios de este mes, el Ministerio de Ciencia presentó un plan en dos fases que prevé que podría sustentar un mercado de 5 billones de yenes (46.000 millones de dólares) para las naves espaciales que salgan y lleguen a Japón.
La idea es que la Agencia de Exploración Aeroespacial de Japón (JAXA) logre reducir drásticamente el costo del lanzamiento de vehículos al espacio.
El cohete H3 de nueva generación del país, cuyo vuelo inaugural está previsto para este año, cuesta aproximadamente 5.000 millones de yenes (USD 46 millones), y la hoja de ruta prevé que tácticas como la reutilización de piezas de cohetes les permitirán reducir ese costo a la mitad para 2030, y bajarlo hasta el 10% a principios de la década de 2040.
El lanzamiento del satélite de Agencia de Exploración Aeroespacial de Japón (Jaxa)
Así, con la ayuda de empresas privadas, prevén dos tipos diferentes de naves espaciales: un avión espacial similar a un transbordador que pueda aterrizar en una pista como un avión normal, y otro que aterrice verticalmente como los cohetes reutilizables de SpaceX.
Los japoneses no son los únicos que se muestran cada vez más entusiasmados con la perspectiva de los vuelos espaciales intercontinentales.
Ya en 2017 Elon Musk sugirió que la Starship de SpaceX podría utilizarse para viajar a cualquier parte del planeta en menos de una hora, y en 2019 especuló que el vehículo podría transportar hasta 1.000 pasajeros por viaje.
La NASA también anunció recientemente una asociación con Virgin Galactic para desarrollar un nuevo vehículo para viajes aéreos civiles de alta velocidad, lo que probablemente se refiera al objetivo de la empresa, tantas veces declarado, de utilizar sus aviones espaciales suborbitales para transportar personas por todo el mundo.
¿Fantasía o realidad?
Singularityhub advierte que si estas ideas se ponen en marcha, es probable que sean increíblemente caras y poco lujosas: “Musk comparó el enfoque con un misil balístico intercontinental y dijo que los vuelos probablemente serán todos en clase turista, sin baños ni comida y con el tipo de restricciones que uno podría esperar en una montaña rusa”.
Otros, agregó el sitio especializado en ciencia y tecnología, creen que los problemas irán más allá de la falta de un trato VIP. “Los humanos simplemente no están hechos para el tipo de aceleración y fuerza G que sufre un misil balístico intercontinental”, dijo Brian Weeden, de la organización de defensa del espacio Secure World Foundation, a The Verge, “y podrían morir fácilmente en el lanzamiento o la reentrada

 

[01] https://www.infobae.com/america/ciencia-america/2021/05/30/japon-quiere-construir-naves-espaciales-intercontinentales-para-principios-de-2040/

La Jaxa trabaja con el avion supersonico que desarrolla Europa (la EADS), el «Transporte hipersónico de cero emisiones ZEHST, presentado el 18 de junio de 2011, por la EADS en el en el Salón Aeronáutico de Le Bourget . con un trijet ( tres tipos diferentes de motores, incluidos turbofan , cohete y scramjets para alcanzar una velocidad máxima de Mach 4,5), En 2015, EADS, ahora Airbus Group estaba trabajando en dos proyectos hipersónicos separados, uno junto con socios japoneses y el otro con participación rusa y australiana.

S-Engine: Motor para volar a Mach 5


LA Agencia de Exploración Aeroespacial de Japón (JAXA) está desarrollando un motor para volar a Mach 5, velocidad hipersonica. El motor se llama S-Engine, es un turbo-reactor, tiene una entrada de aire rectangular, y tras la compresión que sufriría el aire en este difusor convergente, éste estaría excesivamente caliente, por ello pasará a través de un cambiador de calor donde será refrigerado con hidrógeno líquido (el hidrógeno se encuentra a -250ºC). El propio hidrógeno que ha servido de refrigerante es el combustible que se combinará con el oxígeno del aire en la cámara de combustión. El aire, tras pasar el intercambiador de calor, una vez enfriado, será comprimido aún algo más en el compresor (seis veces más), y de ahí a la cámara de combustión. Finalmente, y antes de llegar a la tobera de salida, el aire será acelerado aún más en el postcombustor. La turbina gira arrastrada por los gases de escape a 80000rpm.

S-Engine
Todos los elementos hipersónicos han sido probados en CFC y tunel de viento.

Y hasta aquí sabemos del motor… por una noticia publicada en el 2006, ahora pasamos a una noticia actual… donde leemos que se espera que para agosto de este año se produza su primer vuelo. Instalado en un vehículo experimental, parecido a un misil, que se soltará desde una altitud de 40000 metros desde un globo, y se estima que alcance en vuelo una velocidad de Mach 2.

El S-Engine será el motor del transporte hypersónico cuyo prototipo espera que vuele en 2020 y el modelo definitivo en 2025.

 
 

Japan successfully tests rocket engine propelled by new technology

Jul 27, 2021

Japan on Tuesday successfully tested a rocket engine that was propelled by new technology using shock waves produced by burning a mixture of methane and oxygen gases, with the aim of applying the propulsion method to deep space exploration in the future, the country’s space agency said.

 

The No. 31 vehicle of the Japan Aerospace Exploration Agency's S-520 sounding rocket series lifts off from the Uchinoura Space Center in Kagoshima Prefecture on Tuesday. | JAXA / VIA KYODO
The No. 31 vehicle of the Japan Aerospace Exploration Agency’s S-520 sounding rocket series lifts off from the Uchinoura Space Center in Kagoshima Prefecture on Tuesday. | JAXA / VIA KYODO

The No. 31 vehicle of the S-520 sounding rocket series, measuring 8 meters in length and 52 centimeters in diameter and carrying the engine, lifted off from the Uchinoura Space Center in Kagoshima Prefecture at around 5:30 a.m., according to the Japan Aerospace Exploration Agency.

It reached an altitude of 235 kilometers four minutes and four seconds after the launch and landed in the sea southeast of Uchinoura about eight minutes later, with JAXA retrieving a capsule containing test data in nearby waters.

JAXA is currently developing technology that will allow it to utilize a rocket engine just one-10th of the current size that can also stay in space for extended periods.

Jiro Kasahara, a Nagoya University professor, jointly developing the technology with JAXA, said the test demonstrated that the engine maintained a propelling force in space as expected.

“We will aim to put the technology into practical use in about five years,” he said.

“I’m glad the rocket was launched safely,” said Shinsuke Takeuchi, an associate professor at JAXA, who was leading the test launch. He added the test results are expected to be reflected in future academic achievements.

 

JAXA Tests Pulse Detonation Engine in Suborbital Flight

 

S-520-31 lifts off with pulse detonation engine aboard. (Credit: JAXA)

JAXA said that on Tuesday it tested a pulse detonation engine that uses shock waves powered by methane and other gases to create thrust. The Japanese space agency believes the project could produce smaller but powerful engines for use on deep-space exploration missions.

The engine was launched aboard on the S-520-31 sounding rocket from the Uchinoura Space Center. The Japan Times reported JAXA recovered a capsule with test data from the ocean.

Rocket Model/No. Launch Time
(JST)
Launch Vertical Angle Maximum Altitude Reached Landing Time
S-520-31 05:30 80.0 degrees 235 km/146 miles
(244 seconds after launch)
476 seconds after launch
Source: JAXA

“This experiment is the world’s first flight demonstration of rocket engine technology that safely and efficiently converts shock waves (explosive waves) generated when a mixed gas of fuel and oxygen reacts explosively into thrust,” JAXA said in a press release. “Technology of the detonation engine system (DES) combines a pulse detonation engine (PDE) that intermittently generates shock waves and a rotary detonation engine (RDE) that continuously rotates shock waves in a donut-shaped space.”

The Japan Times reported that JAXA is working the Nagoya University professor Jiro Kasahara to develop an engine that would be about one-tenth the size of ones currently used on deep space spacecraft. The engine, which could be ready for use in about five years, would be able to operate for extended periods of time.

Japan Tests Rotating Detonation Engine in Space for the First Time

Deep space exploration seems to be one step closer.

In a world-first, Japan Aerospace Exploration Agency (JAXA) announced on August 19 that it has successfully demonstrated the operation of a «rotating detonation engine» in space, with the goal of extending the propulsion method to deep space travel in the future.

The «impossible» engine uses spinning explosions inside a ring channel. This method generates a large amount of super-efficient thrust coming from a considerably smaller engine that uses less fuel, and it has the potential to be a game-changer.

Rotating detonation engine tested in space

By Derya Ozdemir Aug 20, 2021
Japan Tests Rotating Detonation Engine in Space for the First Time

 

The Rotating Detonation Engine in space. Nagoya University/JAXA

The revolutionary system was mounted on the S-520-31, a single-stage rocket capable of lofting a 220-lbs (100-kg) payload well above 186 mi (300 km), and launched from the Uchinoura Space Center on July 27. The demonstration was a sounding success.

The rocket began the tests after the first stage separated, firing the rotating detonation engine for six seconds. When the rocket was recovered from the ocean after the demonstration, it was discovered that the rotating detonation engine produced around 500 Newtons of thrust.

 

To put that into context, SpaceX’s large cargo-lifting rocket Falcon Heavy, for example, has three Falcon 9 nine-engine cores whose 27-Merlin engines together generate more than 5 million pounds of thrust at liftoff. This is equivalent to approximately eighteen 747 aircraft. So, while it’s fair to say that the rotating detonation engine is at its nascent stages, JAXA engineers believe that the successful in-space test proves that such engines can allow us to achieve superior interplanetary navigation using less fuel and weight, which will be critical as humanity considers new homes around the cosmos.

Japan hopes to put the technology into practical use within five years, according to a statement last month by Jiro Kasahara, a Nagoya University professor who is collaborating with JAXA on the technology, per the Japan Times.

Overall, rotating detonation engines have the potential to reduce the weight of rocket payloads, lower the costs of launch, and propel us toward the stars, which is why Japan isn’t the only country attempting to engineer them. Back in 2020, a team of researchers announced they’ve built and successfully tested an experimental model of a rotating detonation engine in collaboration with the U.S. Air Force.

The engine design was reported to be being evaluated as a possible replacement for Aerojet Rocketdyne’s RL-10 rocket, and researchers stated the U.S. Air Force is targeting a rocket launch flight test by 2025.

.https://interestingengineering.com/japan-tests-rotating-detonation-engine-in-space-for-the-first-time

 

Sharing Advanced Technologies with the Private Sector

FJR710 Fan Jet Engine
FJR710 Fan Jet Engine

 

Asuka - experimental quiet STOL aircraft
Asuka – experimental quiet STOL aircraft

Q. What is the mandate of the Aviation Program Group?

We research and develop key advanced technologies to help Japan’s aviation industry in the production of domestic passenger aircraft. These include environmentally compatible engines, next-generation supersonic aircraft, safe flight control, and unmanned aircraft for meteorological or disaster monitoring. In other words, our mission is to conduct basic research on promising new technologies, and to pass the results on to Japan’s private sector.
We also maintain Japan’s only large-scale test facilities, which we share with the private sector, since the resources required for such facilities make it almost impossible for a single company to operate them on its own. Additionally, we have expertise in design and analysis technology such as computational fluid dynamics. We work closely with the private sector throughout to design software for use in that sector.
Our achievements in such public-private partnerships, where we have developed a core technology and passed it on to the private sector, include the FJR710 Fan Jet Engine and the introduction of carbon fiber composite into aircraft manufacturing. Development of the FJR710 started in 1971 at the National Aerospace Laboratory of Japan (now part of JAXA), and the technology was recognized worldwide as cutting-edge. Subsequently, the FJR710 technology was adapted for the V2500 engine, co-developed by the United States, Britain, Germany, Italy and Japan. The V2500 has been installed on many fuselages, including Airbus and Boeing aircraft, and more than 70 airlines are using the engine today. Japan’s aviation industry was once left behind by the rest of the world, being completely banned from developing and manufacturing any aircraft in the postwar era. Considering that fact, you could say that the V2500 engine is a first in Japan’s modern aviation industry.
The Japan Society of Mechanical Engineers established the Mechanical Engineering Heritage certification in honor of its 110th anniversary, and awarded the certification to the FJR710, the precursor of the V2500.
Today we are also on the leading edge of carbon fiber technology. Carbon fiber is a material that’s both light and strong, and is used in a variety of products, such as sporting goods. The aircraft Asuka, with a tail unit made of carbon fiber composite, successfully completed its first flight in 1985, but unfortunately, Asuka was not a commercial success. Since then, however, the technology for incorporating carbon fiber composite into airframe has vastly improved, and today the material is being used in a brand-new aircraft, the Boeing 787, scheduled for its first flight in 2008. The primary component of the fuselage and all wings is carbon fiber composite (carbon fiber reinforced plastic) rather than the conventional aluminum alloy. The main wings are manufactured by a Japanese company, Mitsubishi Heavy Industries. It is the first time that Boeing has entrusted the production of the main wings to an external enterprise. Thanks to this, sales in Japan’s aviation industry are rapidly increasing. This is a good example of the kind of success in basic research that we strive for.

Q. What is the significance of JAXA developing aviation technology?

The purpose is to help strengthen the Japanese aviation industry by developing advanced technologies under national leadership. When a new technology is proven successful, new areas of opportunity open up. And once its potential is recognized outside Japan, we can take a leadership role in collaborating with other nations in developing practical applications. In the aircraft field, though, it is not enough to just develop and test new technology. This is a pointless exercise unless it is commercialized and the general public benefits from it. And since the size of the Japanese market is limited, the technology must be applied to a product that’s strongly competitive in the global market. So our ultimate goal is to develop technologies that will be used for passenger aircraft around the world.

Clean Engine Technology

Clean engine (conceptual rendering)
Clean engine (conceptual rendering)

Q. What is a clean engine?

A clean engine is an environmentally friendly engine, which is key to the reduction of harmful gas emissions, noise and fuel consumption. In other words, the engine is quiet, and emits much less carbon dioxide and toxic nitrogen oxide (NOx). And it can also fly aircraft for longer periods and greater distances with less fuel.

Q. What was the motivation behind the development of clean engine technology?

The world is threatened by global warming, which is caused by human activity. So our motivation is to address this serious environmental problem. Our role is to build the fundamental technology, so that the private sector can use it to design and manufacture new, cleaner engines. Until now, the focus of aviation technology had always been on fulfilling our desire to travel faster and farther, without much thought given to the environmental effects. But today we can no longer ignore the air pollution problem caused by emissions from aircraft engines. The quality of our lives is at risk if we do not take immediate action to stop global warming. So developing technology to mitigate environmental damage is obviously very important for the survival of our species.
The International Civil Aviation Organization (ICAO) sets standards on noise pollution and harmful emissions for the international civil-aviation industry. Its requirements are becoming tighter each year, so we must anticipate future regulations and develop engines with lower emissions than the current standards require.
In response to such global demand, the New Energy and Industrial Technology Development Organization (NEDO) launched the Research and Development of Environmentally Compatible Engines for Small Aircraft project (the Eco Engine Project) in 2003. The goal of the project, which is subsidized by the Ministry of Economy, Trade and Industry, is to produce environmentally friendly, low-cost Japanese engines for next-generation passenger aircraft. JAXA is a partner on the technical side.

Q. What is the roadmap for the practical application of clean engines?

Clean-engine development started in 2003, and the core technology was developed from 2004 to 2006. The core technology is a cooling mechanism for the turbines and combustor, which plays a key role in reducing emissions of harmful substances. Over the next few years, we are scheduled to conduct extensive trials of the technology using test engines. And by 2011, we expect to build a clean engine with new technologies developed by JAXA, and to test its performance. This roadmap has been designed to align with each development phase of NEDO’s Eco Engine Project.

Silent Supersonic Technology

Next generation supersonic passenger aircraft (artist's rendering)
Next generation supersonic passenger aircraft (artist’s rendering)

Q. What is the supersonic aircraft JAXA is developing?

It is small aircraft for 30 to 50 passengers. The strength of sonic booms and noise pollution from take-offs and landings will be half that of the Concorde, which was the first and only private supersonic passenger aircraft to date. A sonic boom is an explosive noise caused when the aircraft reaches the speed of sound. Since shock waves from a sonic boom are powerful enough to shatter nearby windows, Concorde aircraft were banned from supersonic flight over lands, and given restricted flight routes. What’s more, the airfare was very expensive due to poor fuel efficiency and small capacity of only 100 passengers. Nonetheless, Concorde remained a very attractive transportation method for international business travelers, since it linked Paris and London with New York and Washington, D.C. in only three and a half hours. Concorde’s demise was the result of a crash in Paris in 2000, but reportedly its commercial failure was mainly due to the problems of the sonic boom and high fuel consumption.
At JAXA, our goal is to develop environmentally friendly supersonic aircraft with reduced sonic booms and noise pollution. We are also working on improving the fuel efficiency of supersonic aircraft by reducing the aircraft’s weight and aerodynamic drag force, which will bring both environmental and economic benefits.

Silent Supersonic Technology Demonstrator (conceptual rendering)
Silent Supersonic Technology Demonstrator (conceptual rendering)

Q. What is the R&D schedule for supersonic aircraft?

Since we started R&D on supersonic aircraft technology in 1997, we have been conducting concept research on an aircraft fuselage system, and research on elemental technologies including aerodynamics and configuration. Thanks to recent advanced numerical analysis technology, we can now model aircraft design to mitigate aerodynamic drag force and noise. However, as numeric calculation is not enough to prove the credibility of new technologies, naturally, we also test them with a wind tunnel and test flights using a prototype. In 2005, with a scaled supersonic experimental airplane, we successfully validated the airframe design for reducing aerodynamic resistance, and acquired a lot of useful data.
We are also planning to build a silent supersonic technology demonstrator to verify our noise reduction technology. For sonic-boom suppression, while the U.S. has achieved it for only the front part of the airplane, we target the entire body. By the mid 2010s, we hope to accomplish a technology that will drastically reduce of sonic booms, and we hope to build viable supersonic aircraft by the 2020s.

Q. Are supersonic aircraft being developed in other countries as well?

The U.S. and Europe are developing supersonic business jets for up to 20 passengers, but so far no one has managed to substantially reduce the sonic boom. If Japan becomes the first to test this technology successfully, we will be far ahead of everyone else.
No single nation can develop supersonic transport on its own, since this requires an enormous amount of capital and the integration of many advanced technologies. Japan is no exception. Thus, developing core technology for supersonic aircraft will be our ticket to participation in such an international project. For example, Japan was accepted as one of the five participating countries in the V2500 engine project, which sold thousands of units around the world, because our years of research gave us a strong knowledge of engine technology. Similarly, our 30 years of experience in composite material research convinced Boeing to manufacture the main wings of the Boeing 787 in Japan. These accomplishments teach us the importance of choosing the right technologies to focus on. If we don’t, Japan will likely not be invited to participate in international projects in the future, which would be a great shame for a nation with such strong support for science and technology.
Supersonic transport will come to fruition sooner or later, but since any substantial revenue is still so far off, it is difficult for private companies to conduct the R&D. Still, many people are interested in this enterprise, and that is why JAXA is exploring these technologies, and bringing in many engineers from the private sector to do the work. I believe that research on cutting-edge and core technologies is something that needs to be done at the national level.

Hypersonic aircraft (artist's rendering)
Hypersonic aircraft (artist’s rendering)

Q. Once supersonic aircraft are a reality, the next target will be even faster transportation, hypersonic aircraft. How is JAXA preparing for this?

We are currently developing the technology for hypersonic aircraft that will travel at Mach 5 (five times the speed of sound), aiming for completion by 2025. The most challenging part is the engine. In hypersonic flight, a regular engine cannot withstand the heat, which goes up to 1000ºC due to the increase in pressure. So JAXA is exploring pre-cooled turbo engines, which would be able to produce massive thrust by using liquid hydrogen to cool the air entering the engine. This would also make the engine environmentally friendly by greatly reducing carbon dioxide emissions. The static firing test in 2007 was successful, and we are planning a balloon flight test in 2008.

Technology for Sustainable Growth

Takashi Ishikawa Photo

Q. What inspired you to specialize in what you are doing now?

I got interested in airplanes when I was still in elementary school, after reading a book my brother had about the wonder of aviation. I always loved making airplane models as a child. In high school, I began to think about studying aviation at university, and I did. I also took to flying gliders in university, and it happened to be a time of transition for glider construction, changing from wood or steel to fiberglass composite. So I began studying composite materials. In fact, that was the time when people were first starting to hear about carbon fiber composite materials. I spent many years after graduation studying carbon fiber as a composite material in aviation, so I was filled with emotion when I found out about the introduction of carbon fiber composite in passenger aircraft structures, and even more so when I heard that the manufacturer of the material would be the Japanese company I had been working with for a long time.

Q. What is your goal now?

My primary goal is to see the successful development and construction of both clean engines and supersonic aircraft. Personally, I hope that the composite material that I have spent many years researching will flourish beyond its use in aircraft manufacturing, to help reduce CO2 emissions, for example, in other areas. Carbon fiber composite is in fact becoming a popular material in many different fields. I believe that it can contribute to sustainable growth in our society on a large scale, and I must say that its invention is a noteworthy achievement in human history. I sincerely hope that the aerospace technologies JAXA develops will succeed on various fronts, and continue to thrive in the future.

 

Dr. Takashi Ishikawa
Doctor of Engineering. Director, Aviation Program Group, JAXA
Dr. Ishikawa graduated from the Department of Aeronautics and Astronautics at the University of Tokyo in 1972. Upon receiving his Ph.D. in 1977, he joined the Institute of Space and Astronautical Science (now part of JAXA), and moved to the National Aerospace Laboratory of Japan (now also part of JAXA) the following year. Dr. Ishikawa studied at the University of Delaware in the United States from 1980 to 1982, where he was a visiting associate professor in 1985. From 1995 to 2005, he was a adjunct professor at the University of Tokyo, Nihon University, and Tokyo University of Science. In 2001, he was appointed Director of JAXA’s Advanced Composite Technology Center. He has been in his current position since 2005. He is also Vice President of the Japan Society for Aeronautical and Space Sciences.
 

 

 

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