Take a trip in a hot air ballon


Hot air baloons flight tecniques

Most hot air balloon launches are mademore exact points called "targets". Once
during the cooler hours of the day, ata pilot has directed the balloon as
dawn or two to three hours beforeclose as possible to a target, a
sunset. At these times of day, the windsweighted marker with an identifying
are typically light making for easiernumber written on it is dropped. The
launch and landing of the balloon.distance between a pilot's marker and
Flying at these times also avoidsthat target determines his or her score.
thermals, which are vertical airDuring some competitive flights, pilots
currents caused by ground heating,will be required to fly to 5 or more
making control of the balloon moretargets before landing. To assist with
difficult. In the extreme, thenavigation, topographic maps and GPS
downdrafts associated with strongunits are used. Another common form of
thermals can exceed the ability of acompetition is the "Hare and Hound"
balloon to climb and can thus force arace. The Hare balloon takes off a set
balloon into the ground.amount of time before the Hound balloons
Sequenceand typically flies with multiple
A hot air balloon flight starts withaltitude changes to make it more
unpacking the balloon from its carryingdifficult for the chasing balloons to
bag. A gasoline-powered fan is used tomatch its flight path. After a set
blow cold (outside) air into theamount of flight time, the Hare will
envelope. The cold air partiallyland and typically lay out a target
inflates the balloon to establish itscross for the Hounds to drop their
basic shape before the burner flame isweighted markers near. As above, the
aimed into the mouth heating the airdistance between a pilot's marker and
inside. A crew member stationed oppositethe target determines his or her score.
the mouth, holds a rope (crown line)Some experienced pilots are able to take
tied to the apex (crown) of thea flight in one direction then rise to a
envelope. The "crown-man" role is twodifferent altitude to catch wind in a
fold, one is to prevent the envelopereturning direction. With experience,
from excessive sway and two is toluck, and the right conditions, some
prevent the balloon rising until it ispilots are able to control a precision
sufficiently buoyant. Once the balloonlanding at the destination. On rare
is upright, pilot and passengers climboccasions, they may be able to return to
into the basket. When the pilot is readythe launch site at the end of the
for launch, more heat is directed intoflight. This is sometimes called a box
the envelope and the balloon lifts off.effect, usually when flying in valleys
During the flight, the pilot's onlywith drainage winds.
ability to steer the balloon is theHazards
ability to climb or descend into windThe dangers of the sport include
currents going different directions.excessive (vertical or horizontal) speed
Thus, it is important for the pilot toduring landing, mid-air collisions that
determine what direction the wind ismay collapse the balloon, and colliding
blowing at altitudes other than thewith high voltage power lines. It is the
balloon's altitude. To do this, thelast of these, contact with power lines,
pilot uses a variety of techniques. Forthat poses the greatest danger. For
example, to determine wind directionsinstance, roughly 90% of serious
beneath the balloon a pilot might simplyballooning accidents in the US involve
spit or release a squirt of shavingpower line strikes. One reason for the
cream and watch this indicator as ithigh frequency of such incidents is the
falls to determine where possible turnsfact that pilots often attempt to land
are (and their speed). Pilots are alsotheir balloons on or near roads in order
looking for other visual clues such asto reduce the amount of off-road driving
flags on flagpoles, smoke coming fromnecessary to recover the balloon.
chimneys, etc. To determine windHowever, in most rural areas where
directions above the balloon, the pilotballoons fly, roads usually have power
will obtain a weather forecast prior tolines running along them.
the flight which includes upper levelThe recent advent of vertically
wind forecasts. The pilot will also sendaerodynamic sport balloons which can
up a helium pilot balloon, known as aclimb and descend at twice the rate of a
met-balloon in the UK and pibal in theconventional balloon (1500 ft/min as
USA, prior to launch to get informationopposed to 700 ft/min) has significantly
about what the wind is actually doing.increased the danger posed by collision
Another way to determine actual windor accidental ground impact during
directions is to watch other hot aircompetition. Many pilots have also
balloons, which are the equivalent of areported strange aerodynamic performance
large met-balloon.during very aggressive climbs, such as
The crew then pack up inflationgreatly reduced air resistance at
equipment and follow the balloon withvertical speeds over +1500 ft/min,
the retrieve vehicle.resulting in a sudden, unexpected
Once the balloon has landed, theacceleration. At present there is little
envelope is deflated and detached fromresearch into high vertical-speed
the basket. The envelope is then packedballoon flight to understand this
into its carrying bag. The burner andphenomenon.
the basket are separated and allThe FAA requires balloons to fly under
components are packed into the retrievevisual flight rules. If equipped with
vehicle.lights that make it visible to other
Controlaircraft, balloons can fly in the dark.
The top of a hot air balloon generallyHowever, such flights are usually
has a flap of fabric (often referred tolimited to either "dawn patrol" flights
as a parachute) that can be pulledthat begin before sunrise with landings
partially open (via a long linemade after there is sufficient light to
connecting the parachute device to thesee any obstacles or to race/record
gondola or basket) to allow the balloonflights that typically go throughout the
pilot to release hot air in an emergencynight and the landing again made during
or for better control of descent. Thedaylight hours.
flap is pulled completely open toTethered balloons are sometimes inflated
collapse the balloon after landing.at night, an event called a "night glow"
In competition, the pilots need to befor the impressive visual effects. At
able to read different wind directionssuch events, pilots will usually operate
at different altitudes. Balloonthe liquid valve known as the whisper
competitions are often called "races"burner (or sometimes called the cow
but they're most often a test ofburner) on the burner creating a
accuracy, not speed. For mostspectacular bright orange flame instead
competitive balloon flights, the goal isof the main valve which creates the more
to fly as close as possible to one ortypical (and efficient) blue flame.



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