SAFA Skysailor Magazine

14 SKY SAILOR November | December 2023 To date, most of the new High C class gliders are de-tuned versions of an EN-D two-liner. The promotional material usually says some- thing like: ‘this is based on our successful EN-D xyz glider’ or ‘…has technology from our EN-D X-Alps glider’, etc. Some don’t even mention the fact. Real two-liners take a long time to R&D, so it’s easier to modify an existing design. Some minor changes in aspect ratio, profile and top speed, et voilà, it passes as an EN-C! This is exactly what happened when High B first arrived. It wasn’t until two seasons later that the designs matured and the inherent style of the glider became a true High B. They were still not gliders you would jump onto from your trusty EN-A, but at least they were dedicated designs in the spirit of the EN-B class. The High Cs to date essentially display EN-D flight and handling characteristics, with recoveries mellower in order to pass the EN-C tests. Usually, and most easily, this is done by re- ducing the top speed, as the max speed at full load asymmetric test is where gliders tend to show their colours and get bumped up a level due to one or two higher (worse) results. Speed and loading To give you an idea of how much speed (and loading) matters, we could (and have) taken a modern EN-A, fitted an unlimited speed system, loaded it to the maximum certified weight and tested it using an open harness. By adding 5-7km/h, the tame EN-A comes out of the collapse test with an EN-B result. At around 10-12km/h more speed, it rotates like an EN-C before autonomously recovering. It still flies like an EN-A, but the test manoeuvre results are vastly different due to the higher energy state. 2 line or not 2 line, that is the question! Sigma 11 Standard C Photos Courtesy: Advance