Performance urge (22): C + D Hybrid Dreileiner

December 4, 2018

So-called three-liners offer the advantage of having fewer lines and therefore less line resistance. Phi presents a true three-liner, which still has a D-plane. The coming Phi Maestro apparently in backlight his inner life. For clarification, the zigzag course of the combined C + D plane is drawn in red here. // Source: Phi, edited Genuine Dreileiners usually have not only the strap, but also the cap only an A-, a B- and a C-plane, on which the lines attack. By dispensing with the D-linkage - even if it's just a short D-gallery forked off the C-line - you can save quite a few line meters. Because each leash creates resistance, three-liners have a small performance advantage per se. But this comes at a disadvantage: in reactions to big accelerated rattles, Dreileiners can be a little more venomous and unpredictable because they lack the support of the rear wing on the D-plane. Structurally, this can be compensated somewhat by the use of C-Wires or Gibus bows. But it is striking: Many manufacturers, who have already constructed true Dreileiner in the meantime, have returned to a D-level - because of the handling. The 3.5-line with a short D-fork is standard today. Perhaps this will change in the future if a new constructive solution, which Hannes Papesh devised for his still young private label Phi, prevails. In the Maestro (High-B, should come on the market in the spring of 2019) can be found in the screen both a C and a D-level. Nevertheless, it is a pure three-liner. The trick here: The articulation points of C + D never sit directly behind each other on a rib. Instead, they are spread across the span in a kind of zigzag line on different ribs (see picture). The diagonals, regardless of whether they originate from the Leinenansatzpunkten on the C and D plane, however, are aligned so that they support the upper sail at the same height. With this C + D hybrid construction, the Maestro Leinenmeter saves like a three-line, which benefits the performance. Mechanically behaves like a 3.5-line. Tip: Learn more about what ideas designers are trying to do to further enhance the performance of paragliders in subsequent episodes of the Power Urgency series.

This article has been translated for your convenience and was originally written in German.