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yeah that was considered

as disclosed F-22 has a thrust to weight(engine) of 8 @ Mach 2.25; g force @ +9

The thrust to weight ratio of engine and g force achievable by plane are different things.
Most of the modern engines have a thrust to weight ratio of about 8:

Pratt & Whitney F119:
Thrust-to-weight ratio: 7.95
Snecma M88:
Thrust-to-weight ratio: 5.7:1 (dry), 8.5:1 (wet/afterburning)
Saturn AL-31:
Thrust-to-weight ratio: 4.77:1 (dry), 7.87:1 (afterburning)
Klimov RD-33
Thrust-to-weight ratio: 4.82:1 (dry), 7.9:1 (afterburning)

But this is just thrust to weight ratio of the engines. All the planes having this engines have thrust to weight ratio of close to 1:
F22, Rafale, Mki, Mig or JF17.

All modern planes have an upper cutoff for g force is 9 g, cause this is considered to be the limit for the pilot. The engine thrust has not so much to do with this g force. It is achieved by fast turns. It is like being on roller coaster. Sudden turns create g force.

To put all this into perspective: Even if a certain engine has thrust to weight ratio of 15, the plane might still have a thrust to weight ratio of 1. For example, suppose a 1 ton engine has thrust of 15 tons. This translates into thrust to weight ratio of 15. Now fit that engine in a 14 ton plane. You now have a 15 ton plane with 15 ton of thrust.

This means you now have a thrust to weight ratio of 1. But this plane can still achieve a 9 g force. How? Take it to high speed, and than make it to turn steeply.

As you asked in your previous comment,

where to find super-pilots who can withstand +15g @ 4~5 mach speed?
or the engines are designed for UAVs.

Source: http://www.defence.pk/forums/china-...ority-projects-next-decade.html#ixzz2Wv7pJhXd

Even if engine has thrust to weight ratio of 15, the plane would not go above the safe limit of 9 g force.
 
The thrust to weight ratio of engine and g force achievable by plane are different things.
Most of the modern engines have a thrust to weight ratio of about 8:

Pratt & Whitney F119:
Thrust-to-weight ratio: 7.95
Snecma M88:
Thrust-to-weight ratio: 5.7:1 (dry), 8.5:1 (wet/afterburning)
Saturn AL-31:
Thrust-to-weight ratio: 4.77:1 (dry), 7.87:1 (afterburning)
Klimov RD-33
Thrust-to-weight ratio: 4.82:1 (dry), 7.9:1 (afterburning)

But this is just thrust to weight ratio of the engines. All the planes having this engines have thrust to weight ratio of close to 1:
F22, Rafale, Mki, Mig or JF17.

All modern planes have an upper cutoff for g force is 9 g, cause this is considered to be the limit for the pilot. The engine thrust has not so much to do with this g force. It is achieved by fast turns. It is like being on roller coaster. Sudden turns create g force.

To put all this into perspective: Even if a certain engine has thrust to weight ratio of 15, the plane might still have a thrust to weight ratio of 1. For example, suppose a 1 ton engine has thrust of 15 tons. This translates into thrust to weight ratio of 15. Now fit that engine in a 14 ton plane. You now have a 15 ton plane with 15 ton of thrust.

This means you now have a thrust to weight ratio of 1. But this plane can still achieve a 9 g force. How? Take it to high speed, and than make it to turn steeply.

As you asked in your previous comment,

Even if engine has thrust to weight ratio of 15, the plane would not go above the safe limit of 9 g force.

All modern planes have an upper cutoff for g force is 9 g, cause this is considered to be the limit for the pilot.
why you have to give additional info which only adds to confirm my point!
 
All modern planes have an upper cutoff for g force is 9 g, cause this is considered to be the limit for the pilot.


why you have to give additional info which only adds to confirm my point!

I am saying that even if they use an engine with thrust to weight ratio of 15, the plane would not go to 15g. You are mixing two different concepts.
 
I am saying that even if they use an engine with thrust to weight ratio of 15, the plane would not go to 15g. You are mixing two different concepts.

it cannot go to 15g because of the human limitation! If it is an uav the 15g is already there at that thrust and speed ( and of course with a sound airplane structure)
 
it cannot go to 15g because of the human limitation! If it is an uav the 15g is already there at that thrust and speed ( and of course with a sound airplane structure)

I rest my case...
 
The SR-71 Blackbird had a top speed of M3.5 and a F-15 with an experimental ammonia oxide engine was even faster, that was back in the late 60s. One relied on after burner and the other was essentially a rocket, of course.

So one may say that with some break through in G Suit design and variable cockpit pressurizing system, a well train pilot of today may endure speeds over M4.0 or acceleration of over 10g.

But then a high thrust to weight ratio can also means increase payload, longer range etc, not just blinding speed.
One most important concern is fuel efficiency though: it takes jet fuel to carry jet fuel.
 
where to find super-pilots who can withstand +15g @ 4~5 mach speed?
or the engines are designed for UAVs.

I think the next gen planes might be pilot-less, remote AC.
The performance limits would be defined by the materials, not human endurance.

Next Generation Air Dominance

The aircraft is to be operated with or without a pilot, depending on the role.
 
I think the next gen planes might be pilot-less, remote AC.
The performance limits would be defined by the materials, not human endurance.

Next Generation Air Dominance

The aircraft is to be operated with or without a pilot, depending on the role.

Yeah that is what I think too.

Also as mentioned in OP, the engine is multifunctional. it says

The CAS report said the engine would use a totally new boosting method. The engine would not only be installed on high-performance jet fighters but high-speed cruise missiles and near-space vehicles.

and as for hypersonic engines the US has this:

May 27, 2010 — An X-51A Waverider flight-test vehicle successfully made the longest supersonic combustion ramjet-powered hypersonic flight May 26 off the southern California Pacific coast.

The more than 200 second burn by the X-51's Pratt & Whitney Rocketdyne-built air breathing scramjet engine accelerated the vehicle to Mach 5. The previous longest scramjet burn in a flight test was 12 seconds in a NASA X-43.
Air Force officials called the test, the first of four planned, an unqualified success. The flight is considered the first use of a practical hydrocarbon fueled scramjet in flight.

X-51 Waverider makes historic ramjet-powered hypersonic flight

It looks like we are on the same path of developing something like that or better!
 
Report shows future trends

Updated: 2013-06-24 07:13

By Cheng Yingqi ( China Daily)

Chinese Academy of Sciences outlines sci-tech ambitions

Science has changed people's lives in the past decade in ways we never before imagined. But where will new technology take us in the future?

Will we find aliens? Invent a human-brain computer? Produce synthetic organisms?

All these are possible, according to a report from the Chinese Academy of Sciences.

On Thursday, the CAS released Vision 2020: The Emerging Trends in Science and Technology and Strategic Option of China, a report composed by 200-plus experts after more than a year of research into trends in the international scientific community and in China.

"Since the start of the global financial crisis, decision-makers have increasingly pinned their hopes for new economic driving forces on technology, so we should thoroughly understand the world's research trends to know where our opportunities lie," said Bai Chunli, president of the CAS.

"Knowing the possible fields and directions for science-technology breakthroughs, we can proactively deploy our own research resources and develop strategic emerging industries to gain the initiative in the next round of development."

The report predicts 22 major events that may substantially influence world science by 2020, including solving the puzzle of antimatter, revealing the mind's circuit diagram and finding evidence of extraterrestrial life.

It also points out sci-tech problems that require more investment in China, such as the cause of dusty haze, quantum information technology, stem cell biology and regenerative medicine.

The space revolution and the structure of matter are two promising research directions for physicists, said Yu Lu, a researcher at the CAS Institute of Theoretical Physics.

"In the 20th century, two major breakthroughs drove the industrial revolution - the theory of relativity and quantum theory," he said. "In this century, are there any scientific problems as important as those two and theories that we are already close to discovering?"

One such example came last year when physicists in an underground laboratory near the Daya Bay Reactor in Guangdong province found a new type of neutrino oscillation, which is crucial for explaining the origins of the universe.

The neutrino oscillation type was a mystery that had been left unsolved by two Nobel Prize winners, and the identification was listed among the Top 10 Scientific Breakthroughs of 2012 by Science magazine.

"That was a highly competitive research direction," Yu said. "As far as I know, three international teams were doing similar experiments, but we were the first that began to collect data, and the first to come to a conclusion.

"This competition will continue, and we're now planning a new experimental site, to keep our leading position," he said.

Energy, resources, materials and manufacturing, information technology, agriculture and population health are strategic research directions, also.

"The report not only represents the research deployment of the CAS, but also mirrors our overall research power in China," said Zhou Qi , deputy director of the CAS Institute of Zoology.

He said that in the past two years, Chinese research programs have received huge attention from abroad, especially in the field of public health.

"Genome technologies enable the application of personalized medicine," Zhou said. "Maybe in the future, we will be able to combine genome technology with industry and make it part of curing infectious disease, tumors and chronic disease."

He said he also sees opportunities in regenerative medicine, such as artificial organs and tissue.

"Within five to 10 years, scientists are likely to grasp the technology of creating synthetic life with stem cell technology, so we also include the direction in our research plan," he said. "However, advanced synthetic life technology raises ethical questions: If stem cells make us no longer need a man and woman to create babies, and if two men or two women are able to have babies, there would be an unprecedented challenge to our ethics.

"As a result, ethical thinking should start now, instead of waiting till we have the technology," Zhou said, adding that to meet the challenge of technology advancement the CAS has started projects for bioethics research.

chengyingqi@chinadaily.com.cn

Report shows future trends |Nation and Digest |chinadaily.com.cn
 

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