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Contour Flying Techniques
Aside from the legal aspects, contour flying is probably
the most difficult flying to perform. Since most contour
flying is done in unpopulated areas, the balloon is rarely
higher than 500 feet AGL, and therefore the balloon's
flight instruments are seldom observed. Because
mechanical instruments have several seconds lag, and
electronic instruments are very sensitive, pilots must
rely on their observation and judgment. Regardless
of the type of instruments in the balloon basket, the
human eye is by far the best gauge when operating
close to the ground.
When flying at low altitude, the pilot must be vigilant
for obstacles, especially powerlines and traffic, and
not rely solely on instruments inside the basket. The
pilot should always face the direction of travel,
especially at low altitude. The pilot's feet, hips, and
shoulders should be facing forward. The pilot should
turn only his or her head from side to side (not the
entire body) to gauge altitude and to detect or confirm
climbs and descents. Facing forward cannot be
overemphasized. There are many National
Transportation Safety Board (NTSB) and FAA
accident reports describing balloon contacts with
ground obstacles because the pilot was looking in
another direction.
Contour flying may require shorter burns than the
standard burn. To fly at low altitudes requires half or
quarter burns. One disadvantage in using small pops
is you can lose track of the heat you are making and
become very noisy. Precise altitude control requires
special burner technique. Another hazard of a series
of too-small burns is that added heat becomes
cumulative and you add heat before you have
evaluated the effects of the last burn. The balloon
actually responds to a burn 10 to 20 seconds after
the burner is used. The choo-choo method of blast
valve use adds heat before you know the effect of
previous burns, is an annoying sound, and makes the
pilot appear undecided.
Contour flying is a complex operation. You must see
all obstacles on or near the balloon path, and remember
their location. You must estimate the terrain or obstacle
height, and always be prepared for an unexpected situation. You must establish a relationship between
the balloon attitude and the terrain or obstacle height.
An estimate must be made of the delay between the
time you command the balloon to perform and the
time you want the balloon to fly the selected flight
profile. Be prepared to adjust your estimates. All these
mental calculations must occur in a few seconds, over
and over again, as you fly a complicated flight profile.
One technique to determine if the balloon is ascending,
flying level, or descending is to compare two nottoo-
distant objects at the side of the balloon path. If
you look directly ahead, or forward and down, objects
on the ground are getting larger as you approach them
and you tend to think you are descending. Just the
opposite may occur if you look at the ground to the
rear of the balloon. As you see objects getting smaller
as they move away from you, you may think you are
climbing. While you want to maintain vigilance looking
ahead in the direction of flight, you must still scan as
much as 45'° to either side and avoid the possible
distortion of looking straight ahead.
What you look for is two objects some distance from
the balloon and some distance from each other in a
straight line. By comparing the relative movement, you
can tell if the balloon is ascending or descending. If
the nearer object seems to be getting taller in relation
to the far object, you are descending. Conversely, if
the farther object seems to be getting taller when
compared to the near object, you are ascending.
Some favorite sighting objects are a power pole as
the near object and the line of a road, field, or orchard
as the far object, because you can observe the line
moving up or down the pole. Water towers with
checkerboard or striped markings are also good
sighting objects. Remember that vigilance is required
to constantly scan the terrain along your path, and
you must be alert to avoid becoming fixated on your
sighting objects. Look where you are flying.
Some Disadvantages and Bad Practices
The line between contour flying and unsafe,
inconsiderate, and misunderstood practices can
sometimes be very fine.
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