Friday 10/24/25 CIVL transmitted a survey to pilots regarding SPORT Class competition. The form stated CIVL Sport Class working group came with a definition of a Sport Class Glider as following :
1. EN-C Certification
2. Flat Aspect Ratio below 6,7
3. Speed limiter
Here are some designer's point of view on the topic. It's a long discussion, feel free to jump to each designer's conclusion written in bold.
Tim Rochas (Niviuk)
Hi
The Sport class definition must be taken with a grain of salt and should be discussed with peoples that are experts in this, here i'm talking about designers, brand test pilots and laboratory test pilots. It's not easy to be precise in the definition and the limitation without thinking to all possible consequences and potential "solutions to cheat"
i will just make some comments below but i think the key is to make something that prevent using a "false EN-C" (basically an EN-D certified in EN-C) to be accepted in this categorie
- IMO aspect ratio limitation is a good point and i think 6.7 is a quite good number, but this must be detailled and properly measured like it's done for the CCC
- Why sport class must be EN-C ? it could be possible to compete even with EN-B IMO. I would be more open saying "maximum EN-C"
- Limitator. Yes every glider in this class must be equiped with a physical / fixed limitator to make sure that you can't go further than what has been tested in certification, but no defined value because some design will need 14cm to acheive good max speed with stability and some 18cm ..
- The way how to measure this limitator must be precisly defined such as what is done for CCC
- --> i don't know what has been precisly proposed for this by CIVL but this is a quite important point
Now if we think deepper in it, today we see that we are facing a problem that a particular test called pitch stability test who will most likely define the maximum speed acheivable by a glider in certification can be an issue in the reality. We can see today with the rise of this EN-C categorie and all the races/ comps around this that some brands will play with the limits and are not always respecting this test or not doing it properly, having as consequency playing with the max speed achievable
--> One option to counter this problem could be the same as i already suggested for the CCC, to limit the maximum speed using IAS measurements controled during certification process coupled with a more restrictive tolerances on line measurements during competition
In all the material related topic, we should think and speak about the future. The effective date of a new regulation must be set at least two years after its publication to give the possibility to all manufacturers to arrive with a new and competitive product according to this new rule.
in Formula one, every big regulation changement are announced years in advance to give time to work properly and not just act in reaction.
My resume is that we need to take time to write properly all the angles of what is the Sport class definition. The direction choosen can be or really good or really bad as it will define how we design such a glider.
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Luc Armant :
Agree. There are quite a few mistakes possible when writing CSC. Flat aspect ratio restriction alone will create an optimum design very flat which is not good for a pleasant and safe wing.
Also a fixed limiter length like CCC could create the same downside
Best is to take the necessary time to work properly on the calss' rules
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Hugo Chaboud (Airdesign) :
Reflection on the Definition of the New “Sport Class”
Hello everyone, it’s Hugo from Air design (Glider R&D team)
I’ve taken note of what has been proposed for the new Sport Class, namely:
* limitation of aspect ratio,
* EN-C certification,
* and the use of a limiter.
I’d like to share a manufacturer’s point of view here and explain while keeping things as simple as possible why we should not rush into decisions that could have major long-term consequences.
The technical terms I’ll refer to are not new, and they are also very well explained (in a different way) in Luc’s document on the proposed evolution of the CCC class.
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1. The limiter and the accelerator travel
The idea of a limiter in this new Sport Class needs to be clearly defined.
Limiting the accelerator travel with a fixed value for the whole class, as in CCC, is totally different from approving each wing individually and assigning a limiter specific to its certification (for example, Model A = 16 cm, Model B = 18 cm, etc.).
This distinction is essential. As I understand the current proposal, “Sport Class” means a fixed accelerator value for all.
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Understanding the basics
When we design a paraglider profile, we usually use numerical analysis to study its aerodynamic characteristics.
Among these is a value that quantifies the stability of the profile its natural aerodynamic behaviour.
A stable profile has a natural tendency to pitch up, moving away from collapse.
This aerodynamic parameter is one of the most important for making a wing stable, especially when accelerated.
Before going further, the following image is not scientifically perfect, but it works pedagogically to explain the core idea behind aerodynamic stability and the role of the center of moment.
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The weather-vane example (a simplified analogy)
Imagine a weather vane or an anemometer.
Its axis is usually placed toward the front so that it remains stable facing the wind.
If you move that axis toward the rear, the behaviour becomes much more erratic—the vane swings in all directions.
That’s roughly the same problem we face in paragliding.
If we increase the thickness at the front of the airfoil, we stabilise the system but « lose reactivity » and the ability to accelerate easily.
A vane with its axis at the rear (an “unstable” profile) needs only a tiny push to rotate, while one with the axis far forward (a “stable” profile) requires much more effort just as a stable glider needs a longer accelerator travel to reach high speed.
In the end, it’s the vane with the axis placed forward that will be the most reliable and will keep its heading most faithfully.
That’s why modern instruments on boats are designed this way; the old “rooster-style” vanes are now mostly found on farm roofs from another century.
i hope you don’t want to go back to last century technology,..
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What this means
Allowing a greater accelerator travel gives stable profiles the opportunity to reach competitive speeds and therefore to participate on equal footing.
If instead we fix a single accelerator length for all, the most unstable profiles will always be the fastest and therefore the most dangerous.
At full speed, the wing is very close to its minimum angle of attack. A small variation is enough to trigger a collapse.
A stable profile resists this, as it naturally pitches up and maintains its position, while an unstable profile tends to pitch down and crosses that limit more easily.
In short: a fixed accelerator travel for the whole C class will not improve safety.
On the contrary, it will push designers toward more unstable profiles to remain competitive.
Those who build the safest wings simply won’t sell them to competition pilots.
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Moving the discussion forward
Several manufacturers are already thinking about how to avoid this trap.
The idea is that, without a limiter or with one set high enough we shouldn’t end up with dangerously unstable wings using excessively long accelerators.
Such wings would indeed fly faster, but at a significant cost to safety we don’t want to see.
We are therefore discussing on the possibility of defining a maximum true-air-speed limit, measurable during certification, rather than a mechanical limit on accelerator travel.
This concept has been discussed for CCC and could make even more sense for defining the Sport Class.
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2. EN-C certification and safety
We really need to stop assuming that “EN-C = safety,” especially if EN-C becomes a competition standard.
Today, all major competition titles are fought for in the CCC category, which is limited only by accelerator travel.
That rule is extremely easy to verify: it’s a single measurement, black or white, yes or no.
The advantage is its simplicity.
The drawback is that a small accelerator range prevents designers from using more stable, and therefore potentially safer, profiles.
That’s why there’s ongoing discussion about updating the CCC rules (which, to be clear, is not an official certification standard).
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How EN testing currently works
In EN-D or EN-C certification, where there is no accelerator limit, maximum speed is determined by a specific test manoeuvre.
The pilot accelerates fully, then brakes within a defined time until reaching 25 % of total brake travel.
In other words, it’s like moving the vane’s axis backward making the system unstable and seeing if the wing remains stable enough not to collapse.
But this manoeuvre depends on many subtle variables:
* whether the pilot is truly at full speed,
* whether the air is perfectly calm,
* the accuracy of the 25 % brake reference point,
* whether the certified prototype is identical to the production wing,
* or even small differences in rod tension or line trim.
For now, this isn’t a major issue (though it’s becoming one with SRS), because the CCC category still acts as a “referee,” avoiding endless debates over who pushed the limits of the standard the most to gain speed.
However, if EN-C certification opens the door to the biggest competition titles, most manufacturers will inevitably push every parameter to the limit to be the fastest.
The result will be wings with more unstable profiles, designed by teams that manage to “shoehorn” them through the standard by subtly influencing the conditions of the pitch test.
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3. Aspect-ratio limitation
On this point why not? It’s probably the best idea of the three.
But we must remember that aspect ratio is not an absolute value.
It depends on the design software and the specific method each manufacturer uses to calculate it.
Since there are many ways to determine aspect ratio, we need a universal measurement method, such as the one already defined and documented for the CCC, to make comparisons meaningful.
It’s likely the simplest measure to implement, but it still requires a clear and shared basis.
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Conclusion (by Hugo still)
All this shows that defining this new class cannot be done overnight.
It requires collaboration between knowledgeable people to build a well-balanced proposal, carefully assessing the advantages, drawbacks and possible side effects of each option.
In my view, it’s essential that manufacturers are directly involved, as we will be the ones designing the wings to meet these requirements.
I wish everyone a good evening, and I hope that within the paragliding community we’ll find the best method to define this new Sport Class using all the available data so that decision-makers can act with full understanding of the implications.
Otherwise, we risk ending up with a poor remake of what often happens in politics, where decisions are made without all the necessary inputs.
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Tom Lolies (Skywalk) :
Dear union members,
Here is my updated statement regarding new CIVL poll for the SRS standard update.
Note: after my initial statement I realized that I was lacking context on the actual scope of this poll. Thus under my own initiative I decided to adjust things a little. Indeed, there is working group in place already (which I recently joined) and the union working group is also being created which will collect a lot of inputs from different experts. Here are the ideas I will present to both groups, in line with my own opinion forged with years of R&D.
1/ EN-C category
I believe using the EN-C certification was a good starting point to prove the potential of SRS competitions. Nevertheless, I think it can only be kept as a short-term solution until a new standard can be found. Pilots rely on EN to forge their opinion about which glider they should fly. However, EN-C alone as a limitation would almost allow any racing machine into the C market. There is already a new trend, that I find concerning, with new EN-C’s pushing the limits of SRS racing. This shows that new rules must be determined to mitigate this. Instead of small additions to the EN-C standard I would advocate for a more radical solution which is to create a new standard, like the CCC, but with more stringent rules. This way we can make sure that there is no incentive for designers to push EN-C wings beyond reasonable limits to shine in SRS. Although I understand this is a lot more work, I think we have a solid WG to build something new. I also see a great opportunity to even step ahead of EN to create a standard that pushes for greater collapse resistance rather than good ‘collapse-ability’ (I will explain below). I am personally happy to participate in writing this new standard, in a transparent manner.
2/ AR limitation
I think AR limitation is a good starting point, but may push towards flatter arc, which goes against recent developments and is a difficult limitation to work with. I am working on a technique to measure projected AR, which would be a much better limitation. If I can find a suitable solution, I will present it to the WGs.
3/ Profile stability and limiter length
Over the last years I started realizing that airfoils with positive moment coefficient (a tendency to pitch up) led to much greater collapse resistance, especially in accelerated flight. However these airfoils have some drawbacks, especially :
- 1/ Greater accelerator travel to achieve a desired speed
- 2/ Collapses harder to perform at full speed
2/ This is why I think introducing folding lines back into EN-C was a great step forward – but I think we should go even further, by replacing full speed collapse tests with full speed collapse resistance tests in a new format for SRS.
1/ If there is an imposed limiter length (such as 14cm as it currently is in the CCC rule) then in order to obtain competitive top speed designers have to use less stable profile that can lead to dangerous collapses at high speed. The current SRS poll suggests that a limiter should be imposed but the length remains at the discretion of the manufacturer, which I think is ideal and should not be changed.
4/ Speed limitation
I think that the best way to avoid an arms race escalation for SRS comps would be a top speed limitation (IAS). This would give us (designers) free hands to increase collapse resistance without being concerned about competitiveness. This is quite feasible during the certification process, but much harder to perform during a comp if a pilot or a manufacturer is accused of cheating. So it does bring fairness questions. That being said, I think fairness should only be a secondary concern for sport’s class.
5/ Conclusions (Tom Lolies still)
The current suggested regulation update for SRS (6.7 AR flat, limiter, EN-C) is only acceptable as quick and simple short term solution. For the longer term, I would like to suggest that we start working on the following :
- Projected AR limitation (that would be more stringent than a 6.7 flat, but announced well in advance to let manufacturers adapt)
- Top speed limitation (performed during the certification process)
- New standard less stringent on full speed collapses but more stringent on full speed collapse resistance
Tom Lolies
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Bruce Goldsmith
The current load test requirements lead to an effective increase in the advantage of large gliders. This makes the competition less fair and also increases the pressure to carry ballast for competitors.
The current EN requirements are based on load testing the large size and then smaller sizes use the line dimensions of the large size. Additional loads tests can be done on smaller sizes is requested by the manufacturer at increased cost.
My initial idea was to reverse this rule. Load test the small size and then use the line strength calculation to increase the safety factor on line sizes on larger sizes. So if a glider top weight is 10% higher then lines sound be designed with an increased factor such as 15 or 20%. It a bit like the noodles idea but you get the added benefit of pilots flying with stronger lines.
However there is a drawback to this idea. This idea considers line strength but the rest of the structure is not tested at a high load.
My second suggestion is to load test the M size (real M size, not competition M size). Then for bigger gliders the extra safety factor can be added. For lower sizes the line design can be calculated in a proportional manner. IE 90% calculated line strength for 90% of the load testing load.
This idea has the added advantage for EN that the load tested glider is also the most sold glider. The alternative of testing only the XL or XS gliders means that the tested glider is at the extreme end of the spectrum and is not the model that is the most used.
I feel this simple change has few disadvantages, and yet moves in the right direction to make competition more fair.
Bruce Goldsmith