Showing posts with label aviation. Show all posts
Showing posts with label aviation. Show all posts

Friday, December 30, 2011

The End of the Concorde

true masked wabbit


I watched a very interesting documentary last night about the famous France and British Concorde on the Discovery Channel (ca.). The End of the Concorde. While watching the beauty, the thrill, the breaking of the sound barrier I knew I wanted to share this with you. Watching what caused the end of this majestic aviation wonder, the tragedy, I knew I had to share it with you.

At the first opportunity this morning I sat down with a pot of coffee and went to search and research what I could find about the famed Concorde.


The invention of Concorde ranks right up there alongside the Wright Flyer and Apollo 11. It was a huge step forward in aviation. At Mach2 it was quite literally ‘faster than a speeding bullet’. It could carry 100 passengers in style. Transatlantic passengers have routinely flown supersonically when they climbed on board one of British Airways or Air France’s Concorde’s. Its passengers were 80 percent business passengers and included film stars, royalty, rock icons and sports legends. Flying at more than twice the speed of sound they could travel form London or Paris to New York in little more than 3 hours.

Every pilot who has flown it thinks it was great - from the cockpit 11 miles above the ground, that’s 55-60,000 feet high, they could see the curvature of the Earth’s surface. Apart from spy planes no one flew higher.

By sheer luck I found two important video clips on YouTube, I had been searching for, one of where after having been denied passage over U.S.A. air/land travel, because of the sonic boom, after lengthy conferences and a captain’s ingenuity of how to take off and lift this gigantic bird without causing any interferences in the sound detectors measuring the Concorde’s safety sound, the USA granted air space to the Concorde. The video will show how the captain leaned the plane at take off in such a manner to not only avoid the sonic boom but make the lift into the skies even quieter than the USA’s new Boeing 747. I found myself smiling and my adrenalin climbing with the Concorde.


I also found the video in its entirety of the final seconds from take off to crash of what caused the end of the Concorde. Ironically not from Discovery Channel but from National Geographic. With detailed explanations of what caused the crash and why the captain could not abort take off.





Excerpt from Discovery Cannel; “It took only 91 seconds to ground nearly three decades of leading-edge aviation engineering. On July 25, 2000, as an Air France Concorde carrying 109 passengers and crew begins its runway take off at Paris' Charles de Gaulle airport, something goes terribly wrong. Unaware of the flames engulfing the delta wing until alerted by the control tower, the pilot faces a no-win situation: Taxiing at 320kph and without the three-kilometre stretch of runway needed to stop safely, Flight 4590 is going too fast to abort take off. He has no choice but to try and get airborne.” End of excerpt.




Monday, May 9, 2011

Red Sprites, Blue Jets and Lightning


Upper-atmospheric lightning or upper-atmospheric discharge are terms sometimes used by researchers to refer to a family of electrical-breakdown phenomena that occur well above the altitudes of normal lightning. The preferred current usage is transient luminous events (TLEs) to refer to the various types of electrical-discharge phenomena in the upper atmosphere, because they lack several characteristics of the more familiar tropospheric lightning. TLEs include red sprites, sprite halos, blue jets, gigantic jets, and elves.

Sprites are large-scale electrical discharges which occur high above a thunderstorm cloud, or cumulonimbus, giving rise to a quite varied range of visual shapes. They are triggered by the discharges of positive lightning between the thundercloud and the ground.The phenomena were named after the mischievous sprite (air spirit) Puck in William Shakespeare's A Midsummer Night's Dream. They normally are colored reddish-orange or greenish-blue, with hanging tendrils below and arcing branches above. They can also be preceded by a reddish halo.They often occur in clusters, lying 50 miles (80 km) to 90 miles (145 km) above the Earth's surface. Sprites were first photographed on July 6, 1989 by scientists from the University of Minnesota and have since been witnessed tens of thousands of times. Sprites have been held responsible for otherwise unexplained accidents involving high altitude vehicular operations above thunderstorms.

Blue jets differ from sprites in that they project from the top of the cumulonimbus above a thunderstorm, typically in a narrow cone, to the lowest levels of the ionosphere 40 to 50 km (25 to 30 miles) above the earth. In addition, whereas red sprites tend to be associated with significant lightning strikes, blue jets do not appear to be directly triggered by lightning (they do, however, appear to relate to strong hail activity in thunderstorms). They are also brighter than sprites and, as implied by their name, are blue in color. The color is believed to be due to a set of blue and near-ultraviolet emission lines from neutral and ionized molecular nitrogen. They were first recorded on October 21, 1989, on a monochrome video of a thunderstorm on the horizon taken from the Space Shuttle as it passed over Australia. Blue jets occur much less frequently than sprites. By 2007, fewer than a hundred images had been obtained. The majority of these images, which include the first colour imagery, are associated with a single thunderstorm studied by researchers from the University of Alaska. These were taken in a series of 1994 aircraft flights to study sprites.

St. Elmo's fire (also St. Elmo's light) is an electrical weather phenomenon in which luminous plasma is created by a coronal discharge originating from a grounded object in an atmospheric electric field (such as those generated by thunderstorms created by a volcanic explosion).

St. Elmo's fire is named after St. Erasmus of Formiae (also called St. Elmo, the Italian name for St. Erasmus), the patron saint of sailors. The phenomenon sometimes appeared on ships at sea during thunderstorms and was regarded by sailors with religious awe for its glowing ball of light, accounting for the name.
Physically, St. Elmo's fire is a bright blue or violet glow, appearing like fire in some circumstances, from tall, sharply pointed structures such as lightning rods, masts, spires and chimneys, and on aircraft wings. St. Elmo's fire can also appear on leaves, grass, and even at the tips of cattle horns. Often accompanying the glow is a distinct hissing or buzzing sound.
St. Elmo's fire is, in fact, a mixture of gas and plasma (as are flames in general, and also stars). The electric field around the object in question causes ionization of the air molecules, producing a faint glow easily visible in low-light conditions. Approximately 1000 volts a centimeter induces St. Elmo's fire; however, this number is greatly dependent on the geometry of the object in question. Sharp points tend to require lower voltage levels to produce the same result because electric fields are more concentrated in areas of high curvature, thus discharges are more intense at the end of pointed objects.

Conditions that can generate St.Elmo's fire are present during thunderstorms, when high voltage is present between clouds and the ground underneath, electrically charged. Air molecules glow due to the effects of such voltage, producing St. Elmo's fire.

The nitrogen and oxygen in the Earth's atmosphere causes St. Elmo's fire to fluoresce with blue or violet light; this is similar to the mechanism that causes neon lights to glow.
Wikipedia.