EN classes explained
Posted on April 29, 2013
Advice to pilots about choosing wings within the EN classes
The EN 926 paraglider standards were formulated by a small working group of experts from several European countries – Working Group 6. This Working Group included Angus Pinkerton and Mark Dale from the BHPA.
The WG6 goal was to create a four-level glider certiﬁcation standard, with the least stable level (D) being ‘safer’ than the previous certiﬁcation schemes’ top levels, and with the most stable level (A) being ‘safer’ than any gliders then in production. To ensure that the WG kept on track (writing, testing and validating EN926 took the best part of ten years!) a simple description of these four classes was set down early on.
These descriptions were purposely kept simple for the beneﬁt of WG6 members whose ﬁrst language was not English. (WG6 was French sponsored, but as a Working Group of the German-sponsored TC135 Technical Committee. And conducted its business in English.) The BHPA FSC has recently recognised that the EN descriptors in the ﬁnal standard, whilst ﬁne for their original purpose as an aide-memoire to the working group, would beneﬁt from further explanation.
The EN paraglider certiﬁcation classiﬁes gliders as ‘A’, ‘B’, ‘C’ or ‘D’. These classes are further explained in terms of the glider’s ‘ﬂight characteristics’ and the ‘pilot skills’ required to ﬂy the machine safely. The idea is that pilots can read the ‘ﬂight characteristics’ and ‘pilot skills required’ descriptors, decide which of those four categories most closely matches their ﬂying situation and needs, and then chose a glider that has been certiﬁed at that level. That way there is aperfectmatch. So step one is deciding whether you are an ‘A’, ‘B’, ‘C’ or ‘D’ pilot. Step two is buying a wing in that class. But have you really understood the descriptors when working out whether you are an ‘A’, ‘B’, ‘C’ or ‘D’ pilot? Let’s take a look at them.
This innocent-sounding heading is used to describe the glider’s tendency to get out of control and fall out of the sky -and the likelihood of you ever getting it ﬂying again. So if you read the descriptor for ‘C’ class gliders, what this is telling you is that with one of these gliders you could reasonably expect ‘dynamic reactions to turbulence’. A dynamic reaction to turbulence would be, say, getting some choppy air on the edge of a thermal and suddenly ﬁnding you have an 80% collapse and the canopy trailing edge is below the horizon in front of you. If you are low on a windy UK hillside you may already be in a situation that cannot be recovered in the time and height available. The descriptor goes on to say ‘Recovery to normal ﬂight may require precise pilot input‘. What this means is that the strong likelihood is that anything other than exactly the correct actions at precisely the right time will almost certainly make the situation worse and result in a cascade of other problems.
Pilot skills required
So what sort of pilot is the glider described above for? ‘Designed for pilots familiar with recovery techniques, who ﬂy “actively” and regularly, and understand the implications of ﬂying a glider with reduced passive safety.’ What does any of this mean? ‘Familiar with recovery techniques’ certainly does not mean the pilot has read about them in a book. It means he or she has done them before, and gets them right. Flies ‘actively’ means the pilot is askilled proponentof ‘active ﬂying’who with constant accurate and precise control movements maintains the canopy pressurised and in position overhead. Flies ‘regularly’ does not mean the pilot ﬂies once a month, nor does it mean boating along some coastal site in smooth air every Sunday. It means ﬂies the best part of 100 hours a year in ‘normal’ thermic conditions and deals with it without drama. And ‘understands the implications of ﬂying a glider with reduced passive safety’ means that you are entirely comfortable with the fact that you are going to experience major collapses and similar events on this wing -especially if you take any liberties with it or don’t pay attention -and that recovery (if possible at all) will depend upon you keeping a cool head and making precisely the right moves at the right time.