Divide ‘EN’, Conquer.

Limitations

One of the lessons I learned while on my paragliding pilgrimage last summer was that the statement, “I fly an EN-B wing because it is safe.” frequently heralds the presence of a pilot who is courting a tree landing. This is in part because the pilot places too much emphasis on the rating of the wing, not realizing the limitations of the current rating system.

The rating system evaluates the characteristics of wings, with the majority of attention given to departure from normal flight. Collapses, spins, stalls are all evaluated by a test pilot and the results recorded. The most benign of behaviours are awarded an ‘A’, while increasingly energetic ones can see awards of up to ‘D’ or ‘F’ (failure). The key points to take away from these tests are:

  1. To minimize atmospheric variations across different tests, the tests are done in calm air over a lake. This in no way reflects the conditions in which we may find ourselves (thermic, gusting, lee, etc).
  2. Collapses are human initiated by pulling on lines. Collapses in real life are initiated by the air at the wing.
  3. The tests are human performed and the results are human judged. While the testers try to remain as objective as possible, subtle variations in pilot behaviour and observation can unknowingly influence the results. The test pilots do their best, but they are human.
  4. The most important (in my mind and the reason for this blog post), these tests try to measure the outcome of a departure from normal flight. There is no real comprehensive measurement of behaviour prior to departure.

Simply put, there are limitations to what the current wing rating system can accomplish. Once we have an understanding of these limitations, we can determine how best to use the system as is and improve upon it for our own needs.

The dividing line

The wing rating system looks almost exclusively at the behaviour of the wing as it departs normal flight. What is normal flight? Normal flight is a loaded, inflated wing directly overhead and under the control of the pilot. Anything that violates these criteria can be considered a departure.

A collapse is one example.

A stall is another.

A spiral may or may not be – the wing is inflated, loaded, and overhead – but is it under the control of the pilot? What may be a welcome experience for the acro pilot may be completely overwhelming for the inexperienced. So, it depends.

So while the rating system deals reasonably well with what happens during and after the dividing line, before it is a different story. The characteristics of the wing before it departs normal flight plays a significant role in how often it will. If the wing is too demanding for the pilot given the conditions, departures could be frequent and overwhelming, even if recovery is quick and without incident.  The rating system may include pilot notes pertaining to the wing, but given that the test is performed in calm air over a lake, it is unlikely to include much commentary on the handing of the wing in thermic conditions. It is this behaviour that needs a standardized, simple to understand method of reporting, much akin to the wing rating system already in place.

Suitability

To cut to the chase, I would suggest splitting Suitability from Passive Safety.

Suitability would be derived from manufacturer data, but we cannot use the data outright.

Why?

The current situation of manufacturer ratings is hit and miss, some indicate the type of pilot, some indicate if the wing is not suitable for students, others indicate the number of air hours.

If we could standardize the manufacturer suitability data, we can make something approaching an apples to apples comparison.  What we need is the target pilot and the air hours per season to remain current on the wing.

So, a wing could come with a pair of standardized ratings -> One from the testing facility for passive safety (the wing rating as it currently stands) and a second from the manufacturer, clearly indicating the target pilot and air hours recommended per year to fly the wing.

Perhaps: (target pilot)-(hours/year) + (passive safety). For example:

School-10 EN A, Leisure-30 LTF B, Advanced-80 EN B, Advanced-100 EN C, etc, etc.

The School-10 EN A would be suitable for a pilot under instruction, a solo pilot pilot flying over 10 hours per year, and has a passive safety rating of EN A.

The Leisure-30 EN B would be suited for a solo pilot flying over 30 hours per year and does not want the workload of the traditional sport wings. A possible second wing candidate.

The Advanced-80 EN B is meant for an experienced XC pilot who flies often and can manage a demanding wing but may not want the post departure behaviour of EN C.

The Advanced-100 EN C. If you are considering this, I can only hope you know what you are doing by this point.

The point of all of this?

Ultimately, the point of this proposed combined rating system is to divorce us from the idea that passive safety and suitability are one in the same. When we realize that a wing rating does not always reflect the workload we may face in the air under that wing, we begin to see the limitations of the current system. From there we can research further, hopefully finding the right wing to then combine with right conditions and pilot.

Happy Hunting.

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