Wednesday, June 30, 2010
Monday, June 28, 2010
Sunday, June 27, 2010
Saturday, June 26, 2010
Friday, June 25, 2010
Thursday, June 24, 2010
Wednesday, June 23, 2010
Tuesday, June 22, 2010
Monday, June 21, 2010
Sunday, June 20, 2010
Lighter than air
Saturday, June 19, 2010
Friday, June 18, 2010
Thursday, June 17, 2010
Wednesday, June 16, 2010
moundial 2010; Opening weekend - 2010 World Cup
Tuesday, June 15, 2010
Alf Poier - Eurovision 2003 - Austria
Monday, June 14, 2010
Preparing for the World Cup
Sunday, June 13, 2010
Saturday, June 12, 2010
Friday, June 11, 2010
Thursday, June 10, 2010
First of the last Space Shuttle launches
Wednesday, June 9, 2010
Tuesday, June 8, 2010
Animals in the news
Monday, June 7, 2010
A2 hypersonic airplane
Development
The vehicle is intended to have about 20,000 kilometres (12,000 mi) range and good subsonic and supersonic fuel efficiency, thus avoiding the problems inherent in earlier supersonic aircraft. The top speed is projected to be Mach 5+. It calls for the use of liquid hydrogen as a fuel, which has twice thespecific energy of kerosene, and can be used to cool the vehicle and the air entering the engines via a precooler.
The developers say it would be able to fly from Brussels to Sydney in about 4.6 hours; compared to around a complete day of travel with normal aircraft. The cost of a ticket is intended to be roughly business class level.[1]
“ | Our work shows that it is possible technically; now it's up to the world to decide if it wants it. | ” |
— Alan Bond, managing director of Reaction Engines Limited |
Design
Capabilities
Alan Bond told The Guardian newspaper:[2]
“ | The A2 is designed to leave Brussels International Airport, fly quietly and subsonically out into the north Atlantic at Mach 0.9 before reaching Mach 5 across the North Pole and heading over the Pacific to Australia. | ” |
Another advantage of the design is that, while the 143 metre-long A2 is much bigger than conventional jets, it would be lighter than a Boeing 747 and could take off and land on current airport runways.
However, the A2 design does not have windows. The heat generated by traveling so quickly makes it difficult to install windows that are not too heavy. One solution Reaction Engines has proposed is to install flat panel displays, showing images of the scene outside.
Engines
The Scimitar engines use related technology to the company's earlier SABRE an engine which is intended for space launch, but here adapted for very long distance, very high speed travel.
Normally, as air enters a jet engine, it is compressed by the inlet, and thus heats up. This means that high speed engines need to be made of technologies and materials that can survive extremely hightemperatures. In practice, this inevitably makes the engines heavier and also reduces the amount of fuel that can be burnt to avoid melting the gas turbine section of the engine, which in turn reduces thrust at high speed.
The key design feature for the Scimitar engines is the precooler, which is a heat exchanger that transfers the heat from the incoming air into the hydrogen fuel. This greatly cools the air, which allows the engines to burn more fuel even at very high speed, and allows the engines to be made of lighter, but more heat susceptible, materials such as light alloys.
The rest of the engine is described as having high-bypass (4:1[3]) turbofan engine features to give it good efficiency and subsonic (quiet) exhaust velocity at low speeds. Unlike SABRE the A2's engine would not have rocket engine features.
Specifications
- Range: 20,000 kilometres (12,000 mi)
- Length: 143 metres (469 ft)
- Fuel: Liquid hydrogen
- Passengers: 300 (Single Class)
- Cruising speed: Mach 5
- Specific fuel consumption: 0.86 lbf/lb·h at Mach 5 (40,900 m/s[4] - 4,170 seconds), 0.375 lbf/lb·h at Mach 0.9 (96,000 m/s[4] - 9,600 seconds)
- Lift to drag ratio: 11.0 at 5.9 km, Mach 0.9, 5.9 at 25 km Mach 5[5]
- Noise: 101 dBa at 450m lateral[5]
Sunday, June 6, 2010
Afghanistan... great pictures from the unterminated war
Saturday, June 5, 2010
Friday, June 4, 2010
Thursday, June 3, 2010
Hydrogen bomb RDS-220
The nuclear test was held on 30 October 1961 saw the explosion is seen from 1,000 kilometers away, even if the shock did not stop three laps of the earth.
The original force had doubled this further, it is expected to spread into Soviet territory with plenty of fallout, probably suppressed the output of this half.
Such mega-development, low during the bombing accuracy was considered necessary.
To uproot it extinguish the point deflected even dropped object.
However, the accuracy is improved surveillance technology and missile soon, ICBM big reason for the existence of these nuclei can not become a dead letter once onboard.
Once a symbol of prestige huge bomb the giant hangars and antiques, has entered into a missile race period.
Current Strategic Arms Reduction Treaty (START) that were mostly destroyed by demolition.
Nuclear Explosion
RDS-220 is also known as Tsar Bomba (emperor of bombs) they are called, were so named according to the theory that it is Western.
Korokoru Tsar Bell is the world's largest exhibition in the Kremlin, it is the world's largest artillery from the Tsar Cannon.
But once it was used as both too large, the name of Tsar Bomba therefore "can not exercise too big," the ridicule that has been planned, he said.