Abstract: A rescue balloon for rescuing individuals from high places such as towers and building includes an enclosed envelope for holding heated air under substantially greater than atmospheric pressure with a burner contained within the enclosed envelope for burning a combustible gas to generate sufficient heated air under pressure in the envelope to provide lift to the balloon. A rescue compartment is carried by the envelope for accommodating rescued individuals and a tether is provided for guiding the balloon as necessary to effect rescues. The balloon includes a porous blast shield positioned within the envelope to prevent direct contact between the envelope and the flame of the burner. The blast shield comprises an upright cylinder supported and secured in fixed relation within the envelope by a plurality of catenaries attached to the blast shield and to the inner walls of the envelope around its perimeter. The burn super-pressurizes the heated air within the envelope.

Abstract: A fuel tank for a propane fuel tank includes an electrically insulative covering positioned in place over substantially the entire exposed surface of the tank to prevent transmission of electric current through the tank by contact of the tank with a source of current. The insulation on the tank also prevents penetration of the tank by arcing of electric current from a spaced apart current source and the tank. The fuel tank is cylindrical and the covering comprises an eight mil thick seamless tube of polyethylene secured by heat shrinking to the outer surfaces of the cylindrical tank. The method according to the invention comprises providing an electrically insulative material, placing the insulative material over the outer surfaces of the tank and bonding the insulative material to the outer surface of the tank.

Abstract: A rescue balloon for rescuing individuals from high places such as towers and buildings includes an enclosed envelope for holding heated air under substantially greater than atmospheric pressure with a burner contained within the enclosed envelope for burning a combustible gas to generate sufficient heated air under pressure in the envelope to provide lift to the balloon. A rescue compartment is carried by the envelope for accommodating rescued individuals and a tether is provided for guiding the balloon as necessary to effect rescues. The balloon includes a porous blast shield positioned within the envelope to prevent direct contact between the envelope and the flame of the burner. The blast shield comprises an upright cylinder supported and secured in fixed relation within the envelope by a plurality of catenaries attached to the blast shield and to the inner walls of the envelope around its perimeter. The burn super-pressurizes the heated air within the envelope.

Abstract: A suspension cable for connecting together the carriage support ropes and the envelope load cords of a hot air balloon in the area of the burner assembly. The suspension cable comprises a non-electrically conductive material having a destruct point sufficiently high to avoid damage from the accidental exposure to the flame of the burner and a tensil strength sufficient to support the balloon carriage. The suspension cable is braided and the non-conductive material comprises an aramid fiber core. The suspension cable includes a non-electrically conductive sheath surrounding the core which will destruct if accidentally exposed to the flame of the burner in order to give an indication that the suspension cable should be inspected.

Abstract: A hot air balloon envelope (11) of the type having a downwardly-directed bottom opening (12) and characterized by being formed of a multiplicity of elongate gores (26) joined along adjacent sides, each of the gores being formed of a multiplicity of joined-together individual fabric panels (30). The improvement comprises at least one observation window (40) positioned in the upper hemisphere of the envelope in substitution for an envelope panel and having a size and transparency sufficient to permit an occupant of a balloon carriage (20) suspended from the envelope to look upwardly through the bottom opening and the observation window to view large objects, such as other balloons in the vicinity above the balloon envelope and not otherwise visible from the balloon carriage.

Abstract: An audible low-fuel alarm (50) for a pressurized propane fuel tank is disclosed. A Hall-effect sensor (57) is mounted in relation to a magnet (35) which is rotated in response to the level of fuel within the propane tank. When magnet (35) is rotated to a position to indicate a low fuel condition, the Hall-effect sensor (57) activates a buzzer 53. A mercury switch (55) prevents false low fuel alarms and conserves battery power during inflation of the balloon envelope.

Abstract: A one-piece load line pocket (30) is disclosed for a hot air balloon (10). The load line pocket comprises an elongate fabric tape having a pair of opposing, longitudinally extending shoulders (31, 32). One of the pair of shoulders is adapted to be placed in overlapping relation, respectively, with an adjacent balloon envelope gore (24) and stitched thereto. The gores (24) are secured together in closely adjacent relation to each other but free of any direct interconnection therebetween. The tape also has a longitudinally extending, tubular pocket (34) intermediate to and integrally formed with the pair of shoulders (31, 32) for freely enclosing a load line (18) which extends from the top to the bottom of the balloon envelope (11) for supporting a balloon carriage (16).