Getting to 7000 feet with a device that I can carry on my back may seem unlikely, but a paraglider is a real aircraft capable of going up.
I start of by laying my paraglider out into a horseshoe configuration with the openings of the leading edge exposed. I then pull the wing toward me, inflating it as it rises. My paraglider is referred to as a ram-air canopy, which means that air is forced inside through openings in the leading edge by the forward motion. A standard parachute is also a ram-air canopy.
With a little headwind I am off. As I fly the shape of the resulting pressure maintains the airfoil. The airfoil is very similar to those on airplanes. It lifts me because the top surface is curved and the bottom surface is straight. Because the upper surface is curved, air must move farther in order pass over the wing than the air under the wing needs to travel. As a result, the air pressure is greater under the wing than above it. This creates the lift I need to fly.
I am suspended by four rows of Kevlar lines. I have two handles, referred to as the brakes or toggles that pull the trailing edge down, slowing the wing. If I pull one brake, I will turn. I can also turn by shifting my weight sideways, which banks the wing. If I pull both brakes, I will slow down. If I pull the brakes too far, I will stall the wing. A stall occurs when the wing flies too slowly or the front of the wing is tilted too high. Air no longer flows smoothly over the wing, but becomes turbulent, and the pressure differential is lost. Altitude is quickly lost, and the pilot must allow the wing to speed up to recover.
Having a wing above me and forward motion is not enough to take me up. I need some help from nature, in the form of a thermal. Thermals are nature’s way of releasing heat from the earth. The sun does little to heat the atmosphere directly; most of the heat transferred to the air comes from the ground. Air is constantly moving up and down when the air heated by the ground is hotter than surrounding air. (Pagen, 1992)
But, this depends on the weather conditions. The air must also be cooler as altitude increases. The amount that the air cools is called the lapse rate. On an overcast day, when the ground is as cool as the air above, there is little thermal activity. In the high desert, where the ground in hot and the air above is cool, the resulting lapse rate results in powerful thermals.
Thermals don’t always rise in steady columns. They can also be intermittent in the form of bubbles or plumes. In humid air they are marked by cumuli, the puffy clouds that form when moist air is carried aloft and condenses. Thermals also rotate due to a force called Coriolis Effect, which is the deflection caused by the rotation of the Earth. Water circling a drain is an example of Coriolis Effect. Furthermore, the air in the center of the thermal rises faster than at the edge. At the very edge, rising air meets sinking air. When all these forces act together, it makes for a wild ride to the top of the thermal.
Negotiating thermals with a paraglider is a tricky business. A paraglider may collapse if air is not continuously forced into the openings. If not corrected, the paraglider may spin. A spin occurs when one wing stops flying and the other wing flies in a circle due to the drag of the stalled side. If a collapse occurs, first maintain a straight course using the brake on the opposite side, then pump the brake on the collapsed side, and voila, the collapse is cleared.
A paraglider appears to be a simple flying device, but much goes into the design and manufacture of one. It is tricky to fly, and understanding their physics is essential to being safe.
Thursday, December 4, 2008
In Praise of the Haka
One night, while watching the evening news, I witnessed a remarkable sight. In Euless, Texas, before a game, the Trinity High School Trojans football team was performing a haka, an ancient Maori ritual dance used to proclaim strength before battle. The dance was brought to Euless by Tongan immigrants who settled in the area. The team stomped their feet, slapped themselves on the sides thighs and chest, made fierce expressions and yelled boisterously, "Ka Mate! Ka Mate! Ka Ora!" (We're going to die! We're going to die! We're going to live!). An ancient Maori battle, when a chieftain was saved by a legendary hairy man, was briefly re-enacted. The crowd roared its approval, and the Trojans, having aroused their warrior spirits, were ready for battle.
This haka is called a ‘peruperu’, used to call the god of war and frighten the enemy. The Maori warriors would perform the dance naked, except for the flax belts they would wear. A haka had to be performed in unison, or the war god would be angry with the tribe. The tribe would then commence fighting, intending to kill all members of the enemy tribe, in order to prevent revenge.
The haka was adopted by several rugby clubs in New Zealand and is associated with New Zealand’s famous All Blacks rugby team, who have performed hakas before matches for over 100 years. Their chant is:
"We are the All Blacks, of the New Zealand people."
"We stand on this field arrayed for battle."
"At our backs we feel the might of tradition wrought by those who have gone before."
"Over our hearts we bear the Silver Fern, emblem of Mana to die for."
"This challenge is now thrown out to you. Take it if you dare for we will not withhold ourselves this day and the faint of heart will surely be lost."
But, the haka is not exclusively a war dance, and not all hakas are performed exclusively by men; they are also performed by women and children. Hakas are also performed to greet guests and celebrate great achievements or occasions. The haka was described by New Zealander Alan Armstrong as, “A composition played by many instruments. Hands, feet, legs, body, voice, tongue, and eyes all play their part in blending together to convey in their fullness the challenge, welcome, exultation, defiance or contempt of the words. It is disciplined, yet emotional. More than any other aspect of Maori culture, this complex dance is an expression of the passion, vigour and identity of the race. It is at its best, truly, a message of the soul expressed by words and posture".
The Trojans would emerge from battle, bloodied and battered, but happy and victorious. I cannot help but contrast the courage and fierce commitment of these young men with the banality of daily life, spent at a job or in front of a television, accumulating material wealth but living without passion or excitement. I am pleased to see the haka come to America. In these times, a little warrior spirit may be good.
This haka is called a ‘peruperu’, used to call the god of war and frighten the enemy. The Maori warriors would perform the dance naked, except for the flax belts they would wear. A haka had to be performed in unison, or the war god would be angry with the tribe. The tribe would then commence fighting, intending to kill all members of the enemy tribe, in order to prevent revenge.
The haka was adopted by several rugby clubs in New Zealand and is associated with New Zealand’s famous All Blacks rugby team, who have performed hakas before matches for over 100 years. Their chant is:
"We are the All Blacks, of the New Zealand people."
"We stand on this field arrayed for battle."
"At our backs we feel the might of tradition wrought by those who have gone before."
"Over our hearts we bear the Silver Fern, emblem of Mana to die for."
"This challenge is now thrown out to you. Take it if you dare for we will not withhold ourselves this day and the faint of heart will surely be lost."
But, the haka is not exclusively a war dance, and not all hakas are performed exclusively by men; they are also performed by women and children. Hakas are also performed to greet guests and celebrate great achievements or occasions. The haka was described by New Zealander Alan Armstrong as, “A composition played by many instruments. Hands, feet, legs, body, voice, tongue, and eyes all play their part in blending together to convey in their fullness the challenge, welcome, exultation, defiance or contempt of the words. It is disciplined, yet emotional. More than any other aspect of Maori culture, this complex dance is an expression of the passion, vigour and identity of the race. It is at its best, truly, a message of the soul expressed by words and posture".
The Trojans would emerge from battle, bloodied and battered, but happy and victorious. I cannot help but contrast the courage and fierce commitment of these young men with the banality of daily life, spent at a job or in front of a television, accumulating material wealth but living without passion or excitement. I am pleased to see the haka come to America. In these times, a little warrior spirit may be good.
Shut Up and Listen!
These are hard times for conversation. America has become a nation of bad listeners, so as a consequence, marriages break up, people get fired, friends become distant and people feel lonely and isolated. We are too preoccupied with our selves. Instead of hearing what is being said, many people often only wait to get their viewpoints across, but the other person isn’t listening either.
Listening is the glue of conversation. Listening and finding common ground opens doors of opportunity, creates friends and allies, heals wounds, gets us hired or promoted and creates trust. Noted Australian psychologist Louise Samways explains, “Many researchers believe that a values basis for acceptance or suspicion is genetically
programmed into human beings…We are bonded by what we can find in common, not by our differences.” (Samways, 2004)
There are three basic types of listening. In competitive listening, the listener is waiting to take the floor. He is disinterested in what others are saying and hears only the flaws in other peoples’ arguments, then launches into his own tirade. This person wants to win the conversation. Passive listening is more attentive and interested, but the listener gives no feedback and little eye contact is made. The listener seems aloof, and the speaker feels devalued and unsure if he is getting across. Active listening, giving the user feedback to verify that what is being said is understood, leads to goodwill between speaker and listener. The active listener seems more understanding and caring, and the speaker is more willing to listen to what the listener thinks.
We are in the fourth decade of what sociologist Tom Wolfe calls the “Lets-Talk-About-Me-Movement”, which began during the “Me Decade”, the 1970s. An unprecedented four-decade economic boom resulted in the quest self-actualization, as defined by psychologist Abraham Maslow, and the individual, already greatly valued in Western culture, became the center of the universe. The individual’s thoughts and feelings became supreme. It was no longer enough to feel your own ambition, wants or pain; everybody else had to feel it too. (In Tom Wolfe’s story “Me and My Hemorrhoids Star at the Ambassador”, a woman describes her painful hemorrhoids to her Erhard Seminar Training class then hears the entire ballroom screaming and moaning in sympathy. Wolfe, 1976) It was all about me, and listening habits deteriorated.
Conversation became a tool for obtaining self-actualization, and many books and articles were written on a set of techniques, called Neural-Linguistic Programming, explaining the importance of mirroring, expressions, gestures, different modalities of speech and body language. NLP became a cornerstone of modern sales. The problem is you are acting and can easily slip up. Can you remember to watch for eye movement, clues that indicate if a person is more visually, audibly or emotionally oriented, match the pace of others’ speech or maintain the correct body language and still be involved? Body language and tone must be congruent in order to be believable. If your words don’t match your gestures, you will lose trust and rapport and appear manipulative.
Instead, you can allow your posture, gestures and tone and pace of your voice to be set by your emotions and attitude. Dale Carnegie taught about empathy in his book “How to Win Friends and Influence People”, written more than three decades before the Me Decade. Carnegie was an old school people person, and never heard of NLP, but he understood what attracts people. His belief system had simple corollaries, such as:
"Speak ill of no man and speak all the good you know of everyone."
“Say ‘Thank You’.”
“Talk about what people want and help them get it.”
“Encourage them to talk about themselves and their interests.”
“Friendliness begets friendliness.”
“Smile!” (Carnegie, 1936)
Today, Mr. Carnegie might add, “Get over yourself”.
When we engage in conversation we decide if it is worth the time, depending on whether rapport is created or broken, either of which can occur instantly. Done effectively, conversation can leave a stranger thinking there is something about you that he really likes, but done ineffectively, you will have difficulty making friends. Ultimately, you are judged by the way you communicate with others. Take an interest in others during conversation, and you will find common ground and friendship.
And isn’t that what we want even with the “Lets-Talk-About-Me-Movement”?
Listening is the glue of conversation. Listening and finding common ground opens doors of opportunity, creates friends and allies, heals wounds, gets us hired or promoted and creates trust. Noted Australian psychologist Louise Samways explains, “Many researchers believe that a values basis for acceptance or suspicion is genetically
programmed into human beings…We are bonded by what we can find in common, not by our differences.” (Samways, 2004)
There are three basic types of listening. In competitive listening, the listener is waiting to take the floor. He is disinterested in what others are saying and hears only the flaws in other peoples’ arguments, then launches into his own tirade. This person wants to win the conversation. Passive listening is more attentive and interested, but the listener gives no feedback and little eye contact is made. The listener seems aloof, and the speaker feels devalued and unsure if he is getting across. Active listening, giving the user feedback to verify that what is being said is understood, leads to goodwill between speaker and listener. The active listener seems more understanding and caring, and the speaker is more willing to listen to what the listener thinks.
We are in the fourth decade of what sociologist Tom Wolfe calls the “Lets-Talk-About-Me-Movement”, which began during the “Me Decade”, the 1970s. An unprecedented four-decade economic boom resulted in the quest self-actualization, as defined by psychologist Abraham Maslow, and the individual, already greatly valued in Western culture, became the center of the universe. The individual’s thoughts and feelings became supreme. It was no longer enough to feel your own ambition, wants or pain; everybody else had to feel it too. (In Tom Wolfe’s story “Me and My Hemorrhoids Star at the Ambassador”, a woman describes her painful hemorrhoids to her Erhard Seminar Training class then hears the entire ballroom screaming and moaning in sympathy. Wolfe, 1976) It was all about me, and listening habits deteriorated.
Conversation became a tool for obtaining self-actualization, and many books and articles were written on a set of techniques, called Neural-Linguistic Programming, explaining the importance of mirroring, expressions, gestures, different modalities of speech and body language. NLP became a cornerstone of modern sales. The problem is you are acting and can easily slip up. Can you remember to watch for eye movement, clues that indicate if a person is more visually, audibly or emotionally oriented, match the pace of others’ speech or maintain the correct body language and still be involved? Body language and tone must be congruent in order to be believable. If your words don’t match your gestures, you will lose trust and rapport and appear manipulative.
Instead, you can allow your posture, gestures and tone and pace of your voice to be set by your emotions and attitude. Dale Carnegie taught about empathy in his book “How to Win Friends and Influence People”, written more than three decades before the Me Decade. Carnegie was an old school people person, and never heard of NLP, but he understood what attracts people. His belief system had simple corollaries, such as:
"Speak ill of no man and speak all the good you know of everyone."
“Say ‘Thank You’.”
“Talk about what people want and help them get it.”
“Encourage them to talk about themselves and their interests.”
“Friendliness begets friendliness.”
“Smile!” (Carnegie, 1936)
Today, Mr. Carnegie might add, “Get over yourself”.
When we engage in conversation we decide if it is worth the time, depending on whether rapport is created or broken, either of which can occur instantly. Done effectively, conversation can leave a stranger thinking there is something about you that he really likes, but done ineffectively, you will have difficulty making friends. Ultimately, you are judged by the way you communicate with others. Take an interest in others during conversation, and you will find common ground and friendship.
And isn’t that what we want even with the “Lets-Talk-About-Me-Movement”?
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