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Sydney Paragliding
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Articles
- The Mitsos reverse launch
- Learn the clouds
- Fun
- Wing tip vortices
- The importance of the diet
- Paramotor fire safety
The Mitsos Reverse Launch
By Bruce Goldsmith (Article reproduced
with his permission)
This spring I went to Australia for the first PWC of 1998, and in Sydney I was met
by my old friend Mark Mitsos, who like me is a hang glider turned paraglider pilot.
We went flying together at Stanwell Park, and I was very impressed by his effortless
reverse launching, and superb control of the paraglider not only in a strong wind,
but also in a small space between several hang gliders lying flat on the ground.
Mark spent a good half-hour explaining his technique to me, and when trying it out
I felt like a student learning to fly again. But, as it was for me, I am sure that
for most pilots it will be worth spending the time to get accustomed to this new
technique: I call it the Mitsos reverse launch.
Mark developed the idea by studying all the existing variations of the reverse launch.
There are 3, which I know of; these are the British Standard Reverse Launch (which
I use), Cross Brake Reverse Launch and lastly the Front and Rear risers with no
brakes.
Mark developed the idea 5 years ago and has been successfully teaching it in his
school, the Sydney Paragliding Centre ever since.
Also the HGFA (Australian HG Federation) have now decided to standardise this as
the best way of reverse launching and to be the only technique taught in schools
in Australia.
The main advantages of the technique are:
Better overall control of the glider.
You can steer the glider as it comes up.
You can stop it overshooting in strong winds.
No need to release the brakes at all.
To start it is important to get in the correct position:
1) Face forward, away from the wing, with the brakes attached to the risers.
2) Turn around to the left, and allow the right riser to pass over your head.
3) Now you should be facing the glider with the right risers on top of the
left risers, with the risers crossed.
4) Pass your right hand over the risers and grab hold of the right brake
from the outside (attached to the riser which is on top).
5) Pass your left hand under the risers and take hold of the left brake handle
(again from the outside).
6) Then grab the shackles at the top of the C risers. (It is safer to take
the C risers first before the A risers, as this gives more control in windy conditions)
7) With your right hand grab hold of the shackles at the top of both A risers.
8) Check that you are holding the C risers, which should be between the two
D risers.
Note: If a glider has only 3 risers, just use the rear "C" risers.
Now you are ready to go. (If you prefer this can also be done the other way around,
by turning to the right.)
The Method:
1) Build a good wall first by pulling on the A risers and the C risers alternately.
2) Lean back on the risers so that they are all tight, then pull gently on
the A risers to guide the glider up into the air.
3) As the glider comes up you should walk sideways towards the centre of
the glider if it does not come up exactly straight.
4) You can also use the C risers to correct the glider if it starts to go
off to the side. Don't pull down on the C risers, but move them from side to side
to steer the glider. Move the C risers from side to side to control the lateral
movement of the glider. Move the risers towards the lower wing. For example if the
left wing is lower then move the C risers to the left to correct it.
5) If it is windy the glider may want to shoot up violently. To stop this
just pull on the C risers to control the speed that the glider comes up.
6) Now the glider is up, it is easy to control the glider overhead using
the C risers or even collapse the glider again to the ground.
7) Alternatively you can turn and launch. As you turn make sure that in light
winds you turn and step forward at the same time otherwise the glider may tend to
overtake you.
Ground handle in a flat field in a smooth wind for an hour before trying it for
real. In fact several ground handling sessions will probably be needed to really
get used to the new technique. For me it felt very strange at first, moving the
C riser hand towards the lower wing felt like the opposite direction to my instincts,
so be careful not to do the wrong thing and smash the glider's nose into the ground.
One common error is to try steering the glider with the A risers. This does not
help at all. Always steer the glider by just using the C risers and walking sideways.
The key to the technique is to take the time to build a good wall. A good trick
to prepare the glider for launch is to move your C's hand left and right as far
as possible each way. This will pull the tips of the glider under and help to keep
them from rising too quickly during the inflation.
It is only possible to use the C's to correct small turns, therefore if the glider
goes a long way out of line the only way to sort it out is to collapse the glider
back on the ground.
It helps to be able to identify the risers easily, particularly the A and C risers.
Most manufacturers mark the A risers, but to identify the C risers I put some red
tape on the shackles of my glider.
In Conclusion:
I have seen many pilots crash as a result of ground handling and launching in strong
winds. Some pilots seem to accept bad and dangerous take-offs and don't regard it
as part of the flight.
Well I have seen as many injuries from launch problems as accidents during flight,
yet the crazy thing is that practicing launch technique is easy as well as enjoyable,
so why don’t people do it.
I strongly recommend that all pilots not familiar with this technique make the effort
to go to a flat field or training slope with their glider and learn it. One day
it could save you from serious injury.
Here is a reference for all pilots of what to expect from the weather
by looking at the clouds. These pictures have been referenced to southern hemisphere
weather conditions.
Contents:
Low Level Clouds
Middle Level Clouds
High Level Clouds
Cloud Base Calculator
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LOW LEVEL CLOUDS
CUMULUS humilis
Fair weather clouds if they show no vertical development. Vertical development
is a good indication for lift. |
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CUMULUS congestus
Can produce showers, usually lead to cumulus nimbus (rain). This is known
as OD (over development). If clouds form in the NW to SW there is a likelihood of
gusty winds and showers in 5 to 10 hr. |
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CUMULUS calvus
Will produce showers in cold southerly bursts. This is the lead up to
thunderstorms. Can become dangerous to pilots due to 'cloud suck'. |
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STRATOCUMULUS opacus
Good indication for worsening conditions and drizzle rain. If found ahead
of a cold front, expect strong gusty winds and showers within 5 to 10 hr. |
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CUMULUS mammatus
This pattern looks like inverted mini cumulus clouds, which are caused
by turbulent up and down drafts. Definately not ideal flying conditions! Expect
heavy showers accompanied by lightning, thunder, strong squalls and if green around
leading edges you can expect hail. |
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Squall Line
If you see this coming towards you, I'd recommend you to find a place
to land. These clouds are indicators for serve winds, heavy rain showers and even
a chance of hail. |
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MIDDLE LEVEL CLOUDS
ALTOSTRATUS translucidus
The sun appears as if viewed through frosted glass. A good indicator
for deteriorating conditions with rain likely in 10 to 15 hr , providing there is
a steady wind from the NW top S. |
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ALTOCUMULUS floccus
Rain likely in 15 to 20 hr if wind is steady from NW, W to S. |
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ALTOCUMULUS castellanus
Great indicator for the possible thunderstorm development. If you see
this in the morning, prepare to be rained apon in the evening. |
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HIGH LEVEL CLOUDS
CIRRUS fibratus
These clouds are formed from ice crystals. They indicate generally fine
weather, but rain can be expected within 20 to 30 hr if the wind is from the NW,
W to S. |
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CIRRUS dense
These clouds are formed from ice crystals. They usually indicate fine
weather, but rain is likely within 20 to 30 hr if the wind is from the NW, W to
S. |
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CIRRUS uncinus
These clouds are formed from ice crystals. They predominately indicate
fine weather, but rain is likely within 20 to 30 hr if the wind is from the NW,
W to S. |
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CIRROCUMULUS small elements
These clouds are formed from ice crystals. Rain is likely within 15 to
20 hr if the wind is from the NW, W to S. Generally fine weather can be expected.
If these clouds appear on a summer morning, there is also a chance of thunderstorms
in the afternoon. |
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The phenomena of wing
tip vortices is caused by the pressure difference between the upper and the lower
wing surfaces. Air, being a fluid, flows from an area of high pressure to an area
of lower pressure. This means that the air on the lower wing surface flows from
the fuselage or centre of the wing to the tips, were it flows around the wing tip
towards the upper wing surface. With the forward motion of the aircraft, it causes
a ' horizontal tornado' emanating from the trailing edge of the wing tip.
At one stage or another we all curse 'the @@##$% who gave a bloody wake'. Well,
here is a series of photo's taken at Kai Tak Airport, Honk Kong. This is about the
most graphical example of wing tip vortices that I've come across. Although it is
unlikely that you will ever fly behind a Boeing 747, I'm sure that you will keep
a good save distance to your fellow pilots after seeing these photo's.
Routine lifestyle choices can reduce
performance and increase susceptibility to diseases. Diet affects mental alertness,
mood and duty performance. Proper nutrition goes hand-in-hand with regular exerciser.
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By: Dr. STANLEY R. MOHLER
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TOO MUCH of one kind of food consumed
during a single day can adversely affect a flight crew or cabin crew member's duty
performance, especially if fatigue or sleepiness is induced.
Too little food or an irregular schedule of food intake can also increase irritability
and decrease endurance. In addition, dietary habits are linked to heart disease,
stroke, high blood pressure, cancer and dental diseases. Moreover, poor choices
can result in health problems that may end crew members' careers, their good health
and even their lives.
Individuals vary in their digesting and processing of food. Some people, for example,
through rapid metabolism, tolerate very high intakes of carbohydrates. Others process
fat efficiently. Still others gain weight after eating too many carbo- hydrates
or fats.
Food is often a source of considerable pleasure and is a reflection of our social
fabric and cultural heritage. Yet what we eat also affects our short- and long-term
wellbeing. Many cultural influences determine what foods are available and are chosen
for consumption.
Home and work environments may include extremes of cold, hot, humid or dry conditions.
Climate often plays a major role in determining what kinds of foods are available.
The senses of taste, smell, sight and touch play a significant role in the daily
dietary cycle. The influence of the senses on the enjoyment of eating is directly
related to an individual's expectations based on childhood experiences, cultural
influences and personal physical characteristics. Taste expectations for food are
essentially the result of a learned process. Everyone has had the experience of
eating an unfamiliar food and initially finding it unpleasant. The same experience
is true of the sense of smell. At first, the smells of some cheeses are unappealing
to many people.
In addition, there are expectations about a food's shape and colour, and any variation
can produce a negative or cautious 34 World Aimews, July 1997. response. Food texture
is also very important. An apple should have a certain resistance that makes biting
into it very different from biting into a banana. Healthy eating habits are described
at length in a report by the US SurgeonGeneral.
The report recommends that people:
- Eat a variety of
foods;
- Maintain a desirable
weight;
- Avoid too much fat,
saturated fat (more solid fat such as that in butter, bacon, beef and pork) and
cholesterol;
- Eat foods with adequate
starch and fibre;
- Avoid eating too
much sugar;
- Avoid eating too
much sodium (includ- ing salt); and,
- Drink alcohol in
moderation, if at all.
Among the most important considerations
in choosing an optimum diet are the following:
Cholesterol is a fatty substance that is linked to the clogging of arteries, especially
the arteries of the heart.
The name cholesterol is derived from the substance's lugh concentration in bile
("chol"), its tendency to separate from other blood components ("ster" - solid)
and its chemical make-up of an alcohol nature ("ol"). Alcohol) is a family of organic
compounds that contain the atomic group OH (oxygen hydrogen) in conjunction with
a chain of carbon atoms. Cholesterol in the diet is metabolized by the liver. For
people who inherit a relatively low number of cholesterol receptors in the liver,
a diet high in cholesterol will result in longer circulation times of inesterol
will be extracted from the blood on each pass through the liver. This will, over
the long term, harm arterial health, as cholesterol deposits accumulate on arterial
walls and begin to block blood flow.
The report explains:
"Intervention to lower elevated blood cholesterol levels has been shown in both
human and animal studies to reduce coronary heart disease risk .... The first line
of intervention is diet therapy. To help reduce cholesterol levels, people should
eat foods, such as vegetables, fruits, whole-grain foods, fish, poultry, lean meats
and low-fat dairy products, that are relatively low in fatty substances.
"A simple rule of thumb is that cholesterol is found only in animal
products (including dairy products) - not fruits and vegetables".
The report says that "high intake of
total dietary fat is associated with increased risk for obesity, some types of cancer
and possibly gallbladder disease.
"Dietary fat contributes more than twice as many calories as equal quantities (by
weight) of either protein or carbohydrates." Types of fats include free fatty acids,
glycerols (a form of alcohol that the body produces from the dietary fats), cholesterol
and the large fat molecules in butter and margarine. Fats are stored in body tissues
if the daily caloric intake, especially fat intake, exceeds daily caloric output.
Fats yield nine calories per gram when metabolized.
A ^calorie is 1 000 calories. A ^calorie is the amount of heat energy necessary
to raise the temperature of one gram of water by one degree Celsius (1,8°F), starting
from 14,5°C (58°F), with pressure constant. The amount of exercise determines whether
excess fat is stored or burned during exertion.
Fats tend to remain in the stomach longer, resulting in a longer period of satisfaction
after a meal; hence, the pleasure some people experience after consuming large amounts
of fatty meat, butter and other foods high in fat content. Using food preparation
methods that add little or no fat is another way to control consumption of fats.
If a person has dif- ficulty metabolizing cholesterol, dietary cholesterol should
be restricted. Medical supervision is often advisable in managing dietary restrictions.
Long-term intake of specific foods
will influence short-term digestive capabilities. An abrupt change in diet might
result in temporary discomfort immediately following eating.
To reduce the likelihood of digestive upset, a crew member should be prepared for
the dietary differences that might be encountered in different national regions
and in other countries. Dry-packaged foods can be carried on flights that do not
require long crew layovers, and fellow crew members may know where familiar food
can be found.
In addition, crew members can experience a variety of foods before the trip - usually
in local restaurants - and focus on foods that may be expected during fu- ture layovers.
Carbohydrates are the quick-energy
substances of the diet. When metabolized, they yield four ^calories (4 000 calories)
per gram. A large, physically active young man may requires 4 000 ^calories of energy
per day. Proteins give structure to the body.
When metabolized, proteins yield four ^calories per gram. Proteins also stimulate
"specific dynamic action," a process in which measurable heat is produced when protein
is metabolized. The preference of those in very cold climates for diets high in
protein and of those in- hot climates for diets high in carbohydrates, is attributed
partly to the different processing mechanisms for these substances and their differing
effects on the body.
Difficulty in processing some nutrients
can cause serious health problems. Diabetes, for example, affects appoximately five
to eight percent of the population. People who require insulin injections to properly
metabolize glucose - the form of sugar that the body uses for its metabolism-are
defined as having insulin-depend- ent diabetes mellitus (Type I diabetes). Those
who have difficulty processing glucose, but can control their diabetes with dietary
restrictions, are defined as having noninsulin dependent diabetes mellitus (Type
II diabetes).
If an individual processes glucose slowly (noninsulin-dependent diabetes mellitus),
sugar intake should be restricted. Controlling obesity by reducing dietary fat intake
can also help control Type II diabetes.
This guideline is consistent with dietary recommendations for the prevention of
coronary heart disease, hypertension (high blood pressure) and some types of cancer.
Through screening programmes, crews should learn about their metabolic characteristics,
such as blood glucose, blood lipids (including the high- and low-density forms of
cholesterol) and other blood elements. Body fat content should also be estimated.
A target body weight can guide food intake and exercise practices. Although a general
knowledge of good nutrition principles is useful, it does not fully enable a crew
member to decide on a specific diet or rate the nutritional quality of particular
food items.
A crew member should be prepared for the dietary differences that might be encountered
in different national regions and in other countries. For day-to-day guidance, various
books provide guidance for optimising consumption of proteins, carbohydrates, fibre,
vitamins and minerals. For example: One book describes a system that scores foods
for their nutritive value, and lists the number of points for particular foods within
the categories of vegetable, fruit, grain, legume, milk/dairy and meat/poultry/fish.
It even gives separate scores for different brands of the same type of food in some
cases. The system also considers food from the view-point of caloric intake and
suggests that an average of about 100 points a day will provide enough calories
to be satisfying, while avoiding extremes of caloric ingestion that could cause
weight gain or loss.
Optimum health is achieved with good
nutrition and exercise. The 206 bones of the human body are actuated by more than
600 muscles. The bones provide support against gravity, and the muscles derive their
energy from ingested food.
For these and other reasons, a lifestyle that includes regular exercise is necessary
for robust health, thereby enhancing individual performance. Each crew member should
determine a long-term diet and exercise programme that is best for him or her and
stick to it. Then use discipline - and no excuses - to follow the programme. Calcium
retention is another benefit provided by exercise. When a muscle contracts against
a bone, the bone retains calcium. With insufficient forces on them (lack of exercise),
bones release calcium *into the blood, after which it is excreted in the urine.
This can ultimately result in loss of bone density, condition known as osteoporosis.
Weight-bearing exercise increases both muscle endurance and size.
Sensible exercise also improves circulatory efficiency and cardiovascular conditioning.
A well-conditioned heart muscle can provide continuing support for the muscles of
the body and meet organ demands for circulating blood. Endurance during long duty
periods will be improved.
Some scientific evidence suggests that
obesity can be linked to genetic factors, but dietary patterns, caloric intake and
energy expenditure play key roles. Long-term efforts to reduce body weight can be
achieved best by proper diet and exercise.
The US report presented a quick method to determine if one is chronically over-nourished.
The method involves measuring the body mass index (BMI) to determine relative obesity.
To calculate BMI, divide body weight in kilograms (one kilogram
= 2,2 pounds) by height squared in metres (25,4 mil- limetres = one inch; 1 000
mm = one metre).
If a man's BMI is above 31, he is said to be severely obese; between 28 and 31,
moderately obese; between 24 and 27 is normal, and below 24 he is underweight. For
women the figures are: above 32, 27- 32, 23-26 and below 23 respectively. Monitoring
BMI gives a crew member quantitative information on the physical effects of lifestyle
and nutrition changes. Crew members should monitor their BMIs to guard against undesired
weight gain. Nevertheless, the body mass index only provides guidelines, which represent
average adult ranges.
Medical knowledge of the complex relationship between diet and health continues
to evolve. Crew members should keep themselves informed about developments relating
to health and performance.
By courtesy: Flight Safety Foundation: Human Factors & Aviation Medicine.
From the first day I
have been flying Paramotors, the issue of fire safety on powered paragliders has
crossed my mind.
Just recently I was sent a German news paper clipping of an accident. Have a look
at this.
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This picture was taken just after the pilot crashed from 10m
onto the ground. The tank ripped from the mounts, cracked open and fuel was spilled
across the hot engine. |
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Due to the fact that this was a farming show, rescuers are on
hand straight away with a fire extinguisher and first aid. |
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The pilot is not expected to live with 3rd degree burns to over
60% of his body. |
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Having a background in commercial aviation
engineering and maintenance, I would like to suggest the following:
- Always clean off
any spilled fuel before starting the motor.
- Carry only as much
fuel as is required for your flight,
- Wear fire retardant
clothing, such as cotton overalls or car racing suits.
- Fit a small car
fire extinguisher in an easily accessible place.
- Don't tilt the motor
too much when getting up, this can cause fuel to spill out of the vent line.
- Don't overfill your
tank. On hot days, fuel can be forced out of the vent line with insufficient expansion
space in the tank.
- Carry out regular
maintenance on your paramotor and inspect fuel lines for chaffing, cracks, discoloration
and kinks.
- Do not fly with
damage that is more than a 20% reduction of fuel line wall thickness!
When you are looking
at buying a new or second hand paramotor, have a look for the following design dangers:
- Hard to exit harness
arrangement.
- Exhaust to close
to petrol tank (air gap of at least 10cm and insulation),
- Petrol tank to close
to motor ( particularly with upside down motors)
- Petrol tank is mounted
below the engine with sufficient air gap to prevent heating of fuel.
- Fuel lines not passing
close to hot surfaces or possible chafing points.
- Strong and flexible
petrol tank mounting.
- Tank vent line placed
in such a position as to not be near a source of ignition (electrical/heat)
- Fire retardant materials
used in harness and construction materials (have not seen it yet on paramotors),
- Insulated tank,
ideally with second liner (have not seen one as yet on paramotors),
- Above all, make
sure it is an easy to maintain unit!
I don't think that there
is a model on the market at the moment which incorporates all possible precautions,
but a lot of good features can be found. Another thing to remember is the fact that
a paraglider is extremely flammable and will react like the 'Hindenberg' airship
to fire (but will only kill one person - you). Even if you manage not to get burned,
I think you would most likely suffer serious respiratory problems from the inhalation
of toxic smoke produced by the materials of your glider.
Always
minimize the risk of becoming a human torch
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