HGFA Skysailor Magazine

28 SKY SAILOR March | April 2019 M ost paragliding textbooks are written for the new pilot who will most likely be flying an EN-A or mid EN-B, and those wings don’t come with trimmers. Therefore, the paragliding textbooks don’t need to cover them. But as a pilot progresses to PG4, s/he might be exposed to wings that DO have trimmers. Hence, there is a need to review trim speed systems – where they are used and the different types. What are trimmers? Trimmers are a type of trim speed system, but unlike a speedbar system which shortens the front risers, a trim system achieves a similar effect by lengthening the rear risers. Of course, in detail it’s a little more complicated than that, but you get the gist of it from the diagrams below. Where do you find trim speed systems? Speed wings , like the Gin Bobcat for example, are supplied with a riser system that includes trimmers – the integrated Gin Bobcat harness does not use a speedbar system, instead it utilises a trim system: Trim system (Diagram from Gin Bobcat manual) Paramotor wings often include a reflex airfoil profile to provide stability at speed, however, large amounts of reflex (controlled by the wing riser trim system) can require more thrust from the motor to maintain level flight – the trim system on a paramotor allows the pilot to adjust the amount of reflex in his/her wing configuration. The Dudek Universal is a good example of a paramotor riser system that incorporates both a trim system AND a speedbar system: Trimmers influence on the wing profile Trimmer settings influence on speed system action. Lengthening and shortening action are given in respect to neutral riser length of 460mm (Diagrams from Dudek Universal owners manual) Paragliders , originally those optimised for cross- country flight had trimmers incorporated into their riser system, so the pilot can select his/her trim speed, therefore reducing the ‘cockpit’ workload. More recently, the latest cross-country gliders from the major manufacturers are reducing the Look through the PG4 study guide and you’ll find there’s a question on trimmers. The strange thing is – there’s not much said about trimmers in the paragliding textbooks! Trimmers