Abstract: A windage brake for a fan descender comprises a rotatable spool connected by drive belts to a fan comprising a radial flow air impeller. A line is wound helically upon the spool. A user of the fan descender puts on a harness (not shown) at the free end of the line and jumps from an elevated position. The line is thereby drawn off the spool and rotates it. The rotating spool drives the fan and also winds a power spring formed by a resilient strip. The windage of the fan regulates the descent of the jumper, the fan being accelerated to a speed at which the braking force is such that the jumper descends at a rate safe for landing on the ground. When the jumper is on the ground, he removes the harness and releases the free end of the line. The line is then automatically retrieved by the power spring and rewound on the spool.

Abstract: Regulating apparatus for a descender comprises a spool 40, a line 48 wound upon the spool 40 to be drawn off during a descent and a fan 44 or similar brake operative upon the spool to limit its speed of forward rotation and hence the rate of descent. The inertial retarding effect of the moment of inertia of the spool 40 is overcome by an electric motor 42 arranged to accelerate the spool 40 during an initial part of the descent. A free-wheeling tether 50 for the line 48 prevents overrun of the spool 40 from picking up the line 48 at the end of a descent. The motor 42 may be run in reverse to rewind the line 48 after a descent.

Abstract: A windage brake for a fan descender comprises a rotatable spool connected by drive belts to a fan comprising a radial flow air impeller. A line is wound helically upon the spool. A user of the fan descender puts on a harness (not shown) at the free end of the line and jumps from an elevated position. The line is thereby drawn off the spool and rotates it. The rotating spool drives the fan and also winds a power spring formed by a resilient strip. The windage of the fan regulates the descent of the jumper, the fan being accelerated to a speed at which the braking force is such that the jumper descends at a rate safe for landing on the ground. When the jumper is on the ground, he removes the harness and releases the free end of the line. The line is then automatically retrieved by the power spring and rewound on the spool.