FireFly Balloonstm are made at The Balloon Works in Statesville, North
Carolina. More of a craftsman's workshop than a factory, The Balloon Works is
where all aspects of a FireFly Balloon are designed and crafted. It's a place
with the earthy, friendly smells of wood shavings, leather and wicker.
Everything that bears the Balloon Works name is made there and the engineers
still design the products in-house to ensure they're built to the exacting
standards that have been progressively developing since 1972.
Concepts Behind The FireFly Balloon
The successful design of a modern Hot Air Balloon is an engineering problem that must combine three distinct components - an envelope, an engine and a carriage - into an integrated, functional whole that is both safe and practical in its assembly. The Balloon Works, with its trademark FlexNet Envelope, Mirage Burner and Triangular Carriage has created the intelligent solution to this problem - The FireFly Balloontm.
The Balloon Carriage is the most complex structure of the entire system and presents the most challenging design problems because of the variety of functions it must serve.
The equilateral triangle is the
most stable shape in nature and The Balloon Works has chosen it as the basis for
many aspects of their product. Most apparent is the Triangular Carriage which is
unique to The Balloon Works. For any given floor area, the triangle provides the
most stable base and longest sides. The three 60 degree angles provide maximum
floor space for pilot and passengers while storing the fuel cylinders, hoses and
instruments safely out of the way in the recessed corners. The ingenuity evident
in its construction is unsurpassed. The 9-ply birch hardwood floor is actually
cradled in a net of six aircraft ropes certified to lift 18,000 pounds. Securely
fastened to a central tie-plate by eye splices and protected from abrasion by
super tough plastic tubing, the suspension ropes run through hardwood skids, up
through the floor, up the carriage structure and out the burner supports to end
in an ultra-strong loop used to fasten the toggles at the end of the envelope
The result is the Mirage Burner. It has the highest heat output certified for balloon engines in the world - over 32 million BTU's at 240 psi tank pressure. Propane is forced through thirty-three feet of vaporizing coil, enters the flow guide to combine with air in a 60 to 1 ratio and is ignited upon exit by three pilot lights producing a long intense, nearly invisible blue flame. Pilot lights have their own pressure regulated fuel supply and the pilot flame burns deep inside pilot burner stacks making it next to impossible for air turbulence to extinguish them. Fire II was made more powerful and integrated as the auxiliary engine with its own separate plumbing, valves, withdrawal lines and burner outlets. Mounting on the uprights in a suspended tripod fashion places all the burner controls in the center of the carriage, equidistant from all sides or corners. Not surprisingly, the Mirage Burner and Fire II have become two of the reasons for the popularity of FireFly Balloons.
Many modern Hot Air Balloons
employ a system of horizontal and vertical load tapes into which the stresses of
flight are transferred. Since these structures are rigid, the fabric panels of
the envelope carry some of the load. This is known as a skin-stressed envelope.
While not necessarily bad, it demands that heavier fabrics be utilized to
maintain the integrity of the system for safe flight. Manufacturers of this
envelope type tend to use nylon for its availability in heavier weights and its
initial strength. They also favor using folded seems to join panels to each
other and to the load tapes.
With Hot Air Balloons, restricting the extent of damage is a matter of safety so the Balloon Works developed the FlexNet Envelope Systemtm. In the system, each fabric panel is surrounded by a strong tape and adjacent panels are sewn into one side of the tape and not to each other. The tape acts as an isolating member, as a mullion in effect, and if a tear occurs, it may travel only as far as the tape before it either stops or is deflected back into the panel. With damage thus minimized, the pilot may be afforded more time to make a safer emergency landing.
The FireFly Envelope Valve
As a means of balloon deflation, the FireFly Envelope Valve, or
parachute valve as it is often called, is by far the most ingenious approach to
date. Its normal resting position is closed and it only operates by deliberate
and continuous action. It is automatically re-sealable, irrespective of how many
times it has been used, and no action is required to accomplish its closing
other than letting it alone. It's capable of proportional valving, releasing
huge amounts of air for deflation or small amounts for adjustments to vertical
flight. Its position at the top of the envelope prevents its dislocation from
snagging. How does it work? First, they put a hole in the top of the balloon
with a stiffener around it to act as a seal. Next, they fill the hole with a
fabric disc that's slightly larger than the hole. Attached to the perimeter of
the disc is a set of lines that connect to each other at a focal point below,
inside the envelope. This point is then attached to a rope which extends down to
the carriage to act as the control for the valve. Another set of lines connected
to the disc, are in turn connected to the envelope at the gore seams to limit
the downward distance of the disc. To prevent the valve from popping out the top
of the balloon, the load cords in the envelope (the ones sliding inside those
pockets) extend past their attachment at the top girdle and connect to a central
steel ring. The valve is held against this rope net with the push of the heated
air inside the envelope. By using some simple laws of physics, the valve
provides a venting capability and versatility superior to anything used before
it in ballooning.
FireFly, Mirage and FlexNet
are registered tradenames of The Balloon Works.
Balloon Rides Over Syracuse