Introduction
This chapter discusses various aspects of in-flight maneuvers. It covers the standard burn, level flight, ascents and descents,
maneuvering and lateral control, and contour flying. This chapter also includes information on chase crew management,
landowner relations, and tethering.
The Standard Burn
To fly with precision, the balloon pilot needs to know how much heat is going into the envelope at any given time and how
that heat affects the balloon’s performance. Balloon pilots have few outside sources, instruments, or gauges to help them
fly. When a balloon pilot uses the burner, there is no direct way of knowing exactly how much lift is increased. Because
there are few mechanical aids to help balloon pilots fly, some methodology must be devised to standardize a pilot’s input
action, so the outcomes of those actions are predictable and the balloon is controllable. The standard burn is one way to
gauge in advance the balloon’s reaction to the use of the burner. [Figure 7-1]
Burner Ratings
During any discussions of burner output, talk usually turns to the issue of “burner ratings”; that is, the
amount of heat actually produced by a specific burner. Invariably, the talk turns into a “my burner is better
than yours” type of exchange. In reality, there is virtually no difference between the burners produced by
the major manufacturers and their respective output.
A pilot needs to understand the concept of British Thermal Units, or BTU, as a measurement of output. A
BTU is defined as the quantity of heat required to raise the temperature of one pound of water by one
degree Fahrenheit. While not particularly relevant to heating air, this has come to be a generally accepted
form of measure for burner output. Of the four major manufacturers, three rate their burners at 18 to 19
million BTU output; the fourth at 43.9 million (with the caveat that that is produced at a supply line pres-
sure of 200 PSI, well above the pressures that most balloonists use). A pilot needs to be aware that BTU
output in a balloon burner equates to the amount of propane that is burned in an hour; BTU output is
usually computed on this basis. Referring to the Propane Primer in Chapter 2, propane has a nominal
value of 91,600 BTU per gallon under ideal circumstances. A simple mathematical calculation indicates
that the average burner (an 18.5 million BTU rating) consumes approximately 202 gallons of fuel per
hour. (18.5 million BTU divided by 91,600 BTU per gallon of propane = 201.96 gallons of fuel)
However, balloon burners are not used for an hour at a time; instead, they are used for very short periods
of time, as discussed in Chapter 7. If the numbers above are recalculated, it can be said that the standard
burn of four seconds, as described in this section, puts approximately 5,139 BTU of heat into the
balloon’s envelope. Remember, this is a theoretical statement of heat available, as no burner is 100
percent efficient.
There are numerous factors involved in burner design, such as volume backpressures, restrictions in the
internal plumbing design, and more, all of which contribute to the final output rating. It is helpful to remem-
ber that the mathematics of burner design reveals the fact that output is a linear equation, when com-
pared to pressure input; there is a direct correlation between the fuel line pressure and the burner’s
output. This is not the case with the noise output of the burner, as the noise output increases exponential-
ly as the pressure is increased. Reduction of burner noise represents the next hurdle in burner design;
perhaps someday it will be possible to enjoy an almost silent balloon flight.
—Mark West and Martin Harns, Aerostar International, Inc.
Figure 7-1. Burner ratings and calculations
The standard burn is an attempt to calibrate the amount of heat being used, and is defined as a burn of four seconds. If each
burn can be made identical, the balloon pilot can think and plan, in terms of number of burns, rather than just using random,
variable amounts of heat with an unknown effect. The standard burn is based on using the blast valve or trigger valve found
Chapter 7: In-flight Maneuvers
on most balloon burners. Some brands use a valve that requires only a fraction of an inch of movement between closed and
open, and some require moving the blast valve handle 90°. While the amount of motion required to change the valve from
fully closed to fully open varies, the principle remains the same—make each burn identical to another.
The inexperienced pilot should begin with the premise that the average balloon requires one standard burn of four seconds
every 25 to 40 seconds in order to maintain level flight. Experience determines the exact length of time between burn
intervals, and how other variables such as weight and ambient air temperature affect those intervals. The primary goal is
to determine the rhythm of burns necessary to maintain level flight. All other maneuvers, then, become a departure from
this point. The burn begins with the brisk, complete opening of the blast valve and ends with the brisk, complete closing
of the valve at the end of the burn. During their training, some pilots count “one, one thousand; two, one thousand; three,
one thousand; four, one thousand” to develop the timing.
The standard burn does not mean a burn that is standard between pilots, but rather, it is an attempt for the individual pilot
to make all burns exactly the same length. The goal is not only to make each burn exactly the same length, but also to make
each burn exactly the same. The pilot must open and close the valve exactly the same way each time. Most balloon burners
were designed to operate with the blast valve fully open for short periods of time. When the blast valve is only partially
opened, two things happen:
1. The burner does not operate at full efficiency.
2. The pilot is not sure how much heat is being generated.
A partially opened valve is producing a fraction of the heat available, but there is no way of knowing what the fraction is.
[Figure 7-2]
Figure 7-2. Activated burner.
Another advantage of briskly opening and closing the valve is to minimize the presence of a yellow, soft flame. During
inflation, for instance, a strong, narrow, pointed flame that goes into the mouth opening without overheating the mouth
fabric or crew is desirable. A partial-throttle flame is wide and short and subject to distortion by wind or the inflation fan. If
less than a full burn is desired, shorten the time the valve is open and not the amount the valve is open. Due to burner design
(and the inefficiency of a partially opened valve), four 1-second burns do not produce as much heat as one 4-second burn.
If the mechanical aspects of flying can be learned, the systematic cadence can be converted into a rhythm that is smooth
and polished. With practice, the rhythm becomes second nature and pilots fly with precision, without thinking about it.
Using the standard burn, pilots can better predict the effect of each burn, minimize the potential danger of a burn to the
envelope, and have a better flame pattern. The standard burn is referred to when discussing specific maneuvers.
Straight & Level Flight
Level flight, or equilibrium, is probably the most important of all flight maneuvers, as it serves as a baseline from which
all other maneuvers are derived. A good pilot maintains level flight with a series of standard burns.
Level flight is achieved when lift exactly matches weight and the balloon neither ascends nor descends, but remains at one
altitude. For every altitude, there is an equilibrium temperature. If a pilot is flying at 500 feet mean sea level (MSL) and
wants to climb to 1,000 feet MSL, the balloon temperature must be increased. This is not only to attain equilibrium at the
new (higher) altitude, but some excess temperature must also be created to overcome inertia and get the balloon moving.
Theoretically, if a pilot were to hold a hot air balloon at a constant temperature, the balloon would float at a constant
altitude. However, there is no practical way to hold the envelope air temperature constant. Each time the pilot burns, the
balloon tends to climb. The air in the envelope is always cooling and the balloon tends to descend. If the subsequent burns
are perfectly timed, the balloon flies in a series of very shallow sine waves. [ Figure 7-3, Line A] Of course, any variable
changes the balloon flight. A heavier basket load, higher ambient temperature, or sunny day all require more fuel (by
shortening the interval between burns) to maintain level flight.
Figure 7-3. Example of normal flight (Line A), flying light (Line B), and flying heavy (Line C).
In discussions of level flight, the terms “flying light” and “flying heavy” are sometimes used and bear explanation. A
balloon is said to be “flying light” when the sine wave being described in the air is predominately on the high side of the
desired altitude [Figure 7-3, Line B]. Many new or inexperienced pilots tend to fly light, and use the vent line in order to
return to the desired altitude; this may create a situation where the pilot gets into a constant overcontrolling exercise and
is best avoided. “Flying heavy” can be described as a scenario where the sine wave is predominately on the low side of
the desired altitude [Figure 7-3, Line C]; if the balloon is left alone, it tends to fall. Flying heavy can be hazardous when
contour flying. A balloon pilot must use all visual cues available and exercise a “finesse” type of control when contour
flying (described later in this chapter).
Through experimentation, standards can be established that may be used as a basis for all flights. With practice and using
the second hand of a wristwatch, a new pilot can fly almost level. The exercise of learning the pattern of burns (each day
and hour is different) is an interesting training exercise, but not a practical real-life technique. The ability to hold a hot air
balloon at a given altitude for any length of time is a skill that comes only with serious practice. Unfortunately, most pilots
do not spend enough time practicing level flight. During the practical test, given a choice of altitudes, it is easier to fly
level at a lower altitude, due to the ease of acquiring visual references. However, the pilot must exercise care not to violate
minimum safe altitude requirements (explained later in this chapter), and must be constantly alert for obstacles such as
power lines in the flightpath.
Ascents & Descents
The temperature of the air inside the envelope controls balloon altitude. A balloon that is neither ascending nor descending
is in equilibrium. To cause the balloon to ascend, increase the temperature of the air inside the envelope. If the temperature
is increased just a little, the balloon seeks an altitude only a little higher and/or climb at a very slow rate. If the temperature
is increased significantly, the balloon seeks a much higher altitude and/or climbs faster. If the balloon is allowed to cool or
hot air is vented, the balloon descends.
Even without the input action by the pilot, it must be remembered that the air inside the envelope is dynamic. The air mass
is constantly moving within the confines of the envelope, attempting to seek a level of equalization. While it varies with
each envelope, input action by the balloon pilot can take from 6 to 15 seconds to be realized as a reaction by the balloon.
Planning the maneuver, anticipating the reaction time, inputting the proper burn, and observing the reaction must result in
smooth and natural movement by the pilot.
Ascents
Using evenly spaced, identical standard burns to fly level, a pilot needs to make only two consecutive burns to have added
excess heat to make the balloon climb. For example, if the pilot can maintain level flight with a standard burn every 35
seconds, and then makes two burns in succession instead of one, the balloon has an extra burn and climbs. How fast the
balloon climbs depends on how much extra heat has been added. Under nominal conditions, if the standard burn has been
made to hold the balloon at level flight and a second burn is within a few seconds (not waiting the 35 seconds), the average
balloon starts a slow climb. Three consecutive burns results in a faster climb.
Once the desired climb rate is established, return to the level flight routine to hold the balloon at that rate. The higher the
altitude, or the faster the rate of climb, the shorter the interval between burns. In an average size balloon (usually a 77, 000
or 90,000 cubic foot envelope) at 5,000 feet, the pilot may be required to make a standard burn every 15 to 20 seconds to
keep the balloon climbing at 500 feet per minute (fpm). At sea level, the same rate may require burning only every 30 to 40
seconds. Burn rates cannot be predicted in advance, but practice provides a basis to begin with and experimentation finds
the correct burn rate for a particular day’s ambient temperature, altitude, envelope size, and balloon weight.
Another skill to develop in ascents is knowing when to stop burning so the balloon will slow and level at the chosen
altitude. The transition from a climbing mode to level flight involves estimating the momentum and coasting up to the
desired or assigned altitude. One methodology is illustrated in Figure 7-4. During this flight, the pilot has decided to leave
his current altitude (A) and climb to another (C). While climbing, the pilot adjusts burn times to be at a 100 fpm rate
of climb by the time they are at a point 100 feet below the desired altitude (B). Under most circumstances, the balloon
“coasts” the additional 100 feet and rounds out, or resumes level flight, at the desired altitude. It may be necessary to use
the vent for a short time to stop the ascent with caution not to vent excessively, thereby causing the balloon to go into a
descent. The balloon pilot must remember that each manufacturer has a specific interval that the vent can be opened while
in flight. Should that interval be exceeded, it can have a disastrous result. With practice and application, the pilot can learn
this skill without the use of the vent, not only conserving fuel, but also flying a much more controlled flight.
Figure 7-4. Ascent schematic
Generally, to achieve a smooth transition to the new altitude, the rate of ascent should not exceed the distance to the new
altitude. For example, if the balloon pilot is 500 feet below the desired new altitude, the rate of climb should not exceed 500
fpm. When the pilot is 300 feet below the desired altitude, the rate of climb should not exceed 300 fpm. An ascent of 200
to 300 fpm is slow enough to detect wind changes at different altitudes, which is helpful in maneuvering. Above 500 fpm,
it is possible to fly through small, narrow wind bands or wind with very small direction changes without noticing. It is a
good idea to launch and climb at a slow speed (100 to 200 fpm) to make an early decision regarding which direction to fly.
Descents
The only direct control of the balloon the pilot has is vertical motion; the pilot can make the balloon go up by adding heat.
Therefore, the pilot can make it come down by venting or not adding heat. For horizontal or lateral motion, a balloon pilot
must rely on wind, which may or may not be going in the desired direction. A good pilot learns to control vertical motion
precisely and variably for maximum lateral choice.
To start a descent from level flight, skip one burn, and then return to the level flight regimen to hold the descent at a
constant rate. Alternatively, hot air balloons are equipped with a vent. When opened, the vent releases hot air from the
envelope and draws cooler air in at the mouth, thus reducing the overall temperature and allowing the balloon to descend.
A pilot should learn to calibrate the use of the vent, as well as the burners, and know how much air is being released in
order to know what effect to expect. For predictability, time the vent openings and open the vent precisely. Parachute vent
balloons usually have a manufacturer’s limitation on how long the vent may be open. Use the vent sparingly; it should not
be used instead of patience, unless a rapid change in altitude is needed.
A new pilot can learn the classic balloon flare by matching the vertical speed indicator (VSI) to the altimeter, i.e., descend
500 fpm from 500 feet above ground level (AGL), 400 fpm from 400 feet AGL. Below 200 feet, a pilot should not use
instruments, but look below for obstacles, especially power lines. This maneuver is illustrated in Figure 7-5. Departing
from the altitude indicated at “A,” the pilot allows the balloon to start a descent. During the descent, the pilot maintains
a reasonable rate of descent, slowing to a rate of 200 fpm at B. By the time the balloon reaches C, the pilot should have a
rate of descent of 100 fpm, and by using one or two standard burns, should be able to level off (“round out”) at the desired
new altitude.
Figure 7-5. Descent schematic.
Rapid/Steep Descents
A rapid, or steep, descent in a balloon is a relative term. A 700 fpm descent started at 3,000 feet AGL is not necessarily
rapid; however, if started at 300 feet AGL, it is rapid and may be critical. Rapid descents should be made with adequate
ground clearance and distance from obstacles.
To execute a steep descent, the balloon pilot must be well aware of the balloon’s response times and have sufficient altitude
for the maneuver. In Figure 7-6, the pilot has initiated a steep descent at Point A. For this discussion, assume that altitude is
1,500' AGL. The descent may be initiated either through the use of the vent or by holding two or three burns. By the time
the balloon reaches the point indicated at B, it may be descending in excess of 500 fpm; the pilot should make a standard
burn at this point, as the air passing over the envelope fabric accelerates cooling. A standard burn ensures that the balloon
maintains a temperature sufficient to keep it under control throughout the maneuver. This burn should not slow the descent.
Figure 7-6. Steep descent schematic (not to scale).
At a point halfway between the ground and the previous burn [ Figure 7-6, Point C], the pilot should make a long (twice
standard length) burn; if there is no reaction from the balloon, then the pilot should do another burn. Immediately upon
sensing a reaction from the balloon, the pilot should stop the burn and allow the balloon to descend to a proper pullout
altitude. [Figure 7-6, Point D] If done properly, the deceleration burns stops the balloon’s descent just above the desired
altitude or the ground. This maneuver requires experience and practice; timing is critical.
During the initial stages of learning this maneuver, the pilot should set a “floor” (altitude lower limit) to practice with.
As the pilot gains more skill, as well as confidence, that “floor” may be lowered until the pilot is able to execute the
maneuver to ground level.
Maneuvering
The art of controlling the horizontal (lateral) direction of a free balloon is the highest demonstration of ballooning skill. The
balloon is officially a nonsteerable aircraft. Despite the fact that balloons are nonsteerable, some pilots seem to be able to
steer their balloons better than others. Being knowledgeable of the wind at various altitudes, both before launch and during
flight, is the key factor for maneuvering.
Maneuvering, or steering, comes indirectly from varying one’s time at different altitudes and different wind directions. The
pilot must have knowledge of the winds at different levels, as previously discussed in Chapter 3, Preflight Planning, as well
as being able to determine the balloon’s direction in flight.
Winds Below
When in flight, winds below can be observed in many ways. Observe smoke, trees, dust, flags, and especially ponds and
lakes to see what the wind is doing on the ground. To determine what is happening between the balloon and the ground,
watch other balloons, if any.
Another means of checking winds below is to drop a very light object and watch it descend to the ground. However,
exercise caution with this method. Title 14 of the Code of Federal Regulations (14 CFR) part 91 allows objects to be
dropped from the air that will not harm anything below. 14 CFR section 91.15, Dropping Objects, states “No pilot in
command of a civil aircraft may allow any object to be dropped from that aircraft in flight that creates a hazard to persons
or property. However, this section does not prohibit the dropping of any object if reasonable precautions are taken to avoid
injury or damage to persons or property.”
Some items that may dropped without creating a hazard are small, air-filled toy balloons, small balls made of a single
piece of tissue, or a small glob of shaving cream from an aerosol can. A facial tissue, about 8" x 8", rolled into a sphere
about the size of a ping-pong ball works well. These balls fall at about 350 fpm, can be seen for several hundred feet,
and are convenient to carry. Counting as the tissue ball descends, a pilot can estimate the heights of wind changes by
comparing times to the ground with the altimeter reading. Experiment by dropping some of these objects, practice reading
the indications, and plan accordingly.
Direction
There are several methods of accurately determining the balloon’s direction at any given moment, particularly with the
advent of low-cost hand-held global positioning system (GPS) units. However, the pilot should be familiar with “old-
school” methods, as GPS units break or fall overboard, and batteries fail.
The pilot should first be positioned in the front of the basket, relative to the direction of flight. Then, the pilot should create
a “sight picture,” using part of the basket’s superstructure, making an allowance for any possible spin of the basket, and
then select a landmark along the route of flight. This process takes a few seconds if the landmark does not change position
in relation to the “sight picture.” Then, the line that may be drawn between the balloon’s current position and the selected
landmark is the ground track of the balloon. It is important that the pilot maintain a constant altitude while performing