Richard Meredith-Hardy, CIMA President
Specifications and rules for inflatable pylons
This text in ms Word format
S10 5.7 INFLATABLE PYLONS
5.7.1 The purpose of an inflatable pylon is to clearly define a point. The point originates at the centre of the base of the pylon and extends vertically to an infinite height.
5.7.2 A pylon may be used to define a point to be turned, or if arranged in a pair, to define the extents of a gate.
5.7.3 If it is intended for a pylon to be turned at low level (any part of the aircraft below pylon height) then the pylon shall be minimum 8m tall.
5.7.4 Pylons shall be constructed and erected in a manner such that:
- They will not deform or fall over in any wind in which it is reasonable to expect the task could be safely flown.
- They will deform in the event of contact with an aircraft.
- There are no supporting lines, or if there are, they do not constitute a hazard.
- Stakes, inflation devices and other hard obstacles associated with a pylon are either buried, protected with padding or positioned to minimize accidental contact by a pilot or aircraft.
5.7.5 The local regulations or task description shall clearly explain what constitutes a valid rounding of a pylon (eg pilot body or whole aircraft) and any limitations (eg not below pylon height).
5.7.6 Unless described otherwise in the task description, a pylon shall be deemed rounded when the pilot crosses in the correct direction the line on the ground with its apex at the pylon and orientated symmetrically to and remote from the two legs of the course at the pylon. (ref. GS A13.1 but without the 90 deg quadrant)
Inflatable pylons have now become an established fact at competitions.
There is some evidence to suggest pylons less than 8m can be dangerous in slalom tasks because there is an enhanced possibility the canopy lines can be hooked over the top in a steep turn, hence 8m is defined as the minimum height for this type of task. It is also worth pointing out simple safety aspects about supporting lines and other obstacles associated with a pylon.
5.7.6 is not designed to supersede anything that might be said in a task description, for example the Clover leaf and other slaloms specifically define which direction a pylon is to be turned. Rather, this provision becomes a default solution for use in those cases when a task description does not adequately specify what constitutes the rounding of a pylon (notably the Chinese Slalom).
Since 5.7.6 defines a way of constructing a specific line which defines when a pylon is rounded, this can also be implemented in any slalom task when split times are being used as something to make a slalom task more interesting and exciting for an audience.
So long as suitable analysis software was available, it may in a future provision be interesting to apply this same technique of defining a line (or gate) at a single point to standard nav task turnpoints. This would then provide a standard means of obtaining a precise time of passing one, which currently does not exist...