A piece of unknown history of paragliding: the very first time a data acquisition device was used to show and characterize an unsafe dive spiral configuration. The instrument (no longer available but a lot of similar instruments are avaible today) was a full 3 axis acceleration data recorder synchronized with inboard or outboard cameras - Note that the red chart is the vectorial sum of the three components of the acceleration. The test pilot demonstrates remarkably - firstly: the pilot simulates faint (because of too hight level of G force) and keeps the command slack as with a pilot unconsciousness (note: at 5 G or more an average pilot is not able to recover from such a faint before... crash) - secondly: the continuum of acceleration increasing to about 5 G's (without any apparent damping of the movement) until the test pilot stops the dive experiment to preserve his own safety! - firdly: two ways to go out (1-opposite command or/and wieghtshift, 2- Tempo action (deep and rapid symetric actions on both command) and going out piloted We could notice that there is several stages and level of severity in instability. - first stage is a continual acceleration on a wide trajectory: - second stage is the entering in spinal phasis: the instantaneous center of rotation moves to a excentrate position between the canopy and the pilot, with the consequence of a violent increase of spinning speed and disorientation of the pilot by a surge of lateral G forces. So what is it materring about? The problem is that six years ahead these edifying experiments - and all the similar following tests communicated at the main world manufacturers - the homogation protocols do not consider the G level produced during the tests as a critical value to record, cote and level (for example to validate the accessibility and compliance of a wing with the skills of leasure pilots it is targetting with an A or B label). Would you consider waiting for a decade more for such important and available safety informations - or not? Ask for them to the manufacturers, ask for them to test laboratories, ask for them to PMA... Now... And have a training, test and debriefing session in a G-force trainer: a few devices are available in Europe In France, see les Passagers du Vent paragliding school at Annecy (Seiko and Pierre NAVILLE)