Sailplane pilots often don't understand paragliders, why they do it, it's just a completely different world, and why you'd switch from a sailplane to paragliding with such incredibly poor performance, and it's actually dangerous, and it might work, and I don't know what, it was very difficult at the beginning because I really wasn't understood, but in the end you have to look at yourself and see what feels good, what's fun, what brings you happiness.
Podz-Glidz, the Lu-Glidz podcast. Stories from the cosmos of paragliding. Today with Werner Duidold. And I am Lucian Haas.
Some sailplane pilots just call us paragliders tea bags because we apparently hang motionless in the air for them. When you're zooming through the skies at over 100 km/h, completing cross-country flights of more than 1,000 km, gliding 70 km to the next bath without any issues, and just shrugging with a smile at a 30 km/h headwind, you can certainly feel quite superior. That's why the step the Austrian Werner Duidold took is all the more astonishing, at least from the perspective of hardcore sailplane pilots. At the peak of his sailplane career, back in 2008, when he won one of the most renowned competitions in the world at the time at the age of 39, he simply switched.
From the cockpit of a glider into a paragliding harness. Without ever returning to soaring again. What drove him to do this is what Werner Duidold tells us in this 90th episode of Podz-Glidz. Of course, it's mostly about the comparison and the advantages of soaring—and of paragliding. And what both disciplines could learn from each other. But Werner has even more interesting stories to offer. He is known in the scene as the publisher of valuable thermal and valley wind maps of the Alpine region. As a graphic designer, he designed the new design line of Nova gliders. Recently, he gained insights into the paragliding scene in Iran during a trip. Furthermore, he is considered the inventor of the large Stoderzinken triangle.
His soaring experience played an important role in this, by the way. If you enjoy Podz-Glidz, please consider supporting my work as a patron. You can find out how to do that easily and without any obligation on the support page of my blog website, Flugleits.
Werner, what exactly is the Baron Hilton Cup?
The Baron Hilton Cup is actually an old institution among glider pilots, founded 30 years ago by Baron Hilton—who is the grandfather of Berges Hilton—together with Helmut Reichmann, the well-known German glider pilot. Back then, it was a competition that always ran over two years and was held all over the world. The idea was that you fly a large FVI triangle, or triangle, in a specific glider class according to a certain set of rules. And whoever achieved the highest flight point during those two years was then invited by Baron Hilton to Nevada to the Baron Hilton Ranch to go gliding for a week.
And you won this Baron Hilton Cup once?
Exactly. So, I won it.
When was that?
That was in 2008. And the exciting thing was, it was actually the very last Baron Hilton Cup. Because Baron Hilton was already 83 years old at the time. And he said he wanted to end the Baron Hilton Cup as long as he was still fit and could decide for himself. So, it was actually very exciting for me, because it was the last one and already a special distinction. And within the soaring world, it was a very coveted prize that actually many pilots worldwide wanted to win.
That means you were one of the most successful glider pilots in the world at that time, or at least in Austria, is that how you'd put it?
Well. This prize wasn't won. In my class, it wasn't just open worldwide, but there were regions. Because you just can't compare the regions of, for example, you can't compare America in terms of performance with Europe, with the Alps, or with Australia. I won back then in a soaring class, the 15-meter Rheinklasse. It's like with paragliders, where there are the ENB, ENB, END classes; there are also different performance classes for soarers. And I won it with the class in the Rheinklasse and in Europe. That means the Europe league, so to speak. And then over there in America, there were pilots from Europe,
from America, Asia, and Australia, and I believe Africa. So, there were several regions where it was advertised.
Then you can say, okay, the most successful glider pilot in Austria of this period, roughly. Or one of the most successful. Yeah,
...or maybe even Europe's in that class, because I won the European ranking in the Rhine class. And that was relatively exciting because the big flights, the really big ones from the Bernd Hilton Cup, are flown as FI triangles. And Austria isn't really a place where you can fly really, really, really big FI triangles. I mean, you can, but very rarely. The big FI triangles are usually flown in Spain. I did it a bit differently. Instead of an FI triangle, you can fly a flat triangle, but you have a different factor and have to fly further accordingly than an FI triangle. So I actually flew a very large flat triangle, which is actually one of the largest flat, thermally flown triangles in Austria since 2008.
No one has flown further than that yet.
Was that only in Austria, or did you fly along the main Alpine ridge? Like, all the way into Switzerland and so on?
Yes, you have to fly relatively far for that. So, my route was registered as 1,083 kilometers.
Oh wow.
That means, so I live in the Enztal valley. That's near Schladming, in the middle of Austria. And that flat triangle... well, Austria actually becomes too small there. So I started from my place at 9:30 a.m. local time and flew east towards Vienna to Hohenwand. That's pretty much the last corner of the Eastern Alps. I then turned at Hohenwand and flew from there—it was 530 kilometers, I think—in a direction towards the west. So I passed the Heimendorf airfield towards Switzerland, over the Flüeler Pass, until just before Desentes. That's about 20 kilometers east of the Oberalpenpass at the level of Lake Lucerne in Switzerland.
And then back to my place in Eigen.
Was that your biggest or longest glider flight you've ever done?
It was my longest, yes. The difficulty with a flight like that is, of course, the scale and the weather. You very rarely get weather conditions where you can take off so early, where the weather is homogeneous from east to west, where you really have consistently good conditions. So the weather has to be right. And back then, it was actually a weather situation that I'd say still only happens every five to ten years. It was an Omega situation. It was a weather situation where we flew 1,000 kilometers for five days in a row in a glider. That happens very rarely. And it was a special weather situation. I was stoked.
Everything worked out exactly as I had imagined. And then I just went ahead and did it.
And it worked.
When you say that was the pinnacle, did you not experiment with the glider as much after that? Or did you not do as many long distances with it anymore?
No, it was like a peak for me. I've always oriented my entire soaring career towards long-distance flying. And the Bernd-Hilton-Cup was actually a goal of mine. You don't just win the Bernd-Hilton-Cup out of nowhere. It has a performance progression in itself. You have to do that for it. You can't just say, I'm flying 1,000, 1,000 kilometers now. Instead, you need the right aircraft. You have to be capable of flying it. You have to have flown several long distances beforehand. It takes years to actually develop to that point. And then I won it.
And I actually experienced something like, I've reached the goal. And somehow, I then lost my goal. Like, my... what do I do now? And I also overdid it a bit. I actually mostly just went flying for the performance. And for the record. And I lost one of them. I lost my passion for flying. The joy of flying. It was actually so performance-oriented and focused on this Bernd-Hilton Cup.
And then the whole thing just kind of fell away from me. And I had a really strange experience. I was over at the Bernd-Hilton. The following year, I was invited. And you have to imagine the Bernd-Hilton Range; it's in Nevada. And it's a paradise for cross-country flying. So, the base altitude is 6,500 meters. And there, you can fly 1,000 kilometers in a glider in 6 hours. So, incredibly fast average speeds.
And I flew there. And I was up at 6,000 meters in a plane. With oxygen. And I flew around. And I sat inside the plane. And I had this feeling. Okay. And that was it. I didn't enjoy flying anymore. It was really weird. And I had a real crisis of meaning, like what's going on now. Now I've reached the big goal. And actually, I'm not happy about it at all. And that was a really difficult phase for me back then.
There's probably a term for that. Maybe you can understand it better if you look into those kinds of things. But for me, it was really at the peak. I actually decided for myself that I'm going to do less soaring, or maybe not do it at all anymore.
Was the reason, or was it the trigger, that you sort of switched over to paragliding?
No. I've always been interested in paragliding. I got my paragliding license relatively early. That means I got my license in 2004, I think. But I haven't done much of it. Because I didn't do soaring either. Because I prioritized it lower.
But you did soaring before paragliding? Exactly. Okay. I
I started gliding in 1989.
That's relatively young. You were around 19 or 20 then, something like that.
I was 20, yeah. At 20 years old. Yeah, I got my paragliding license in 2004. That was a phase back then. We sailplane pilots basically said, well, if you can sailplane, then you can do paragliding too. We all tried it out. And that's when I got my license. But I never actually flew. And then, after I was over at Bernhilden's in Nevada, I went back to my flight school to renew my license. The paragliding license. I kept renewing it. Then I went to the practice field and did some flights. And back then I got a new one, so an A-glider, a training glider. And I noticed that the glider, that it had changed incredibly much compared to 2004. Suddenly I had a glider that was totally easy to fly.
The one with very few lines. The one that didn't have any. The one that started super well. The one that had more performance than before. I had the feeling, ah, this is fun. And then I immediately unpacked a glider at the flight school. And I drove to Loser with us. And went flying. And then I had an evening flight where, very late with the last evening sun, I was soaring over a small hill at the middle board. And then a bird came towards me. Very close to me. And then I soared with this bird, which was hanging very flat in the sun. And then I suddenly, I felt it again. That.
What?
The feeling. The beauty. This passion, actually. This, why I actually fly. And that was such a micro-experience. But it was so profound for me because it went so deep. And it was so simple. It was so simple to fly with the glider. Someone was flying almost alone. I was maneuvering with the bird. And it electrified me. I almost teared up. It was really emotionally overwhelming. After this whole story. That's a story that has developed over years. Since then, it's actually not letting me go. It
it was almost like a rebirth, something like that.
Exactly, yes. That also led me back to where I actually come from. Because I don't actually come from soaring. I come from model aviation. So I actually started as a child. And I had this playful approach with model aviation. So I had free flight models. I had remote-controlled models. That was a playful approach. And that was very simple flying. And paragliding. This one flight suddenly brought me back there again. To this childhood memory. To this beautiful, simple thing. That's why I enjoy paragliding so much now. Because the playfulness is simply what makes me happy. It's incredibly fascinating for me. I enjoy it.
Every single day, non-stop. It's just great.
Do you still go hang gliding sometimes today? No. Not at all anymore? No.
It's totally interesting. That
is it like a closed chapter for you?
Absolutely, yes. For my sailplane colleagues, it was totally difficult. Because they couldn't understand at all what was going on with me. When you basically suddenly stop sailplane flying and start paragliding. It's all paragliding, sailplane flying. Paragliding is very contrary. And sailplane pilots often don't understand why paragliders do it. It's just a completely different world. And why you'd step down from a sailplane to paragliding, to such an incredibly poor performance. And actually, it's dangerous and it could work and I don't know what. It was already very difficult at the beginning because I really wasn't understood. But in the end, you have to look at yourself. And see what does you good. What is fun then? What makes you happy? What moves you forward?
For me, that chapter was simply closed.
With your knowledge of basically both worlds, you could be a great ambassador. What would you explain to each of them? Where do the respective advantages of both types of aviation basically lie? Let's start with soaring. I'm a paraglider pilot now. Explain to me why I absolutely have to try soaring sometime.
Well, as a paraglider, I'd say you have to experience these incredible glide ratios and the incredible performance of a sailplane in real life. Because a sailplane is a highly refined machine. You can cover incredibly long distances with them efficiently. And that's fantastic for a paraglider. I remember I once had a sailplane flight where I flew 300 kilometers in one direction. That was me. To Adelberg, that's far. With two lifts. That means circling twice. So, all with line flying, catching lifts, with a straight flight path, with efficient flight technique. But overall, two lifts. That's of course an extreme case.
That's a factor of 1 to 10. So we as paraglider pilots can, if everything goes well, sometimes cover maybe 30 kilometers with two lifts. With a bit of wind maybe still in the background. Yeah. But then it's like, you can do ten times that with a glider. You can
you can do. Yes, that works, yes. Or when you think about paragliding, with sailplanes you think in much larger dimensions. That means if I have a lift with a sailplane, I think, what am I doing in 50 kilometers? Or what am I doing in 70 kilometers? Those are dimensions that you as a paraglider have to grasp. It's incredible. And the glide ratio view, for me the biggest problem was with the paraglider. I had a calibrated glide ratio view from the sailplane. And it's of course incredibly flat. And at the beginning, I had disappointments with the paraglider that were unbelievable to me. I couldn't get from one mountain to another. I almost couldn't believe it. And when the valley wind came, that was incredible for me. And then experiencing paragliding too, that the wind, for example the headwind, if you have 20 km of headwind,
is actually irrelevant for the sailplane, it doesn't matter. I barely dealt with valley winds as a sailplane pilot either. It was hardly an issue for me.
Also because you usually fly over it?
Because you're flying over it, you're rarely that far down. Or rather, if you have a headwind, a valley wind, it's relatively uncomplicated for a glider because the polar curves of the glider are very flat. And if you have the best glide at 90 and you have a 20 km headwind and you're flying at 110 or 120 for me, then the performance is still incredibly good. That means you only notice it in very extreme cases where it comes down to the last meter. But in reality, the valley wind is negligible.
And that's something you have to experience as a paraglider. I think it's a fascinating experience. I would recommend it.
And if I'm a glider pilot now, what fascinating experience in paragliding would you have to tell me about—or would you recommend to me?
In soaring, you're inside your cockpit. That means you're actually somewhat insulated from the outside world in a way. You don't really notice what's happening outside immediately. But with a paraglider, you hear much more. The sound of the air against the helmet, what you pick up there, and the smells. And the intensity of the lift in a paraglider is incredibly denser than in a glider.
And I think a glider pilot should experience once how alive the air actually is and how much is going on in the air. You also see constant sinking while paragliding. You see so many things flying around. And with this small-scale flying, where you can stay on the tiniest little slopes and turn away. You have a thousand times more lift for a paraglider than for a glider. Because many of the lifts that a paraglider picks up, a glider can't turn into. He can only use them to stretch out his glide angle, but he can't turn into them. That means this incredible variety of lift in the air, a glider pilot should experience that once.
If we're talking about two different worlds here, where you'd really say, okay, the experience is different, but also what you can do with the given conditions is so different—would you still say that a paraglider can learn something from a glider? Or are they really such separate worlds that you could say, no, it's just something else, and you can't really transfer that much directly?
Well, you can definitely transfer things. For example, I try to transfer the flight style of sailplanes to paragliding. When I was sailplane flying, I was always mindful of flying lines and having as little circling as possible. That means it's not characterized by an ultra-fast forward flight that goes point-to-point, but rather it's really terrain-oriented, wind-oriented, and tries to maximize the glide distance and then circle the strongest values. And I do the same thing with paragliding. That means I try to maximize the glide distance and then circle the strongest values. That means I try to maximize the paragliding then and circle the strongest values. And then select the strongest values and simply fly the most efficient, best line. And that's also with me, my flight style is also like that, I have a paraglider, I hardly fly, so I hardly need full throttle from the glider.
I fly most of my routes at half throttle. And even though I fly B-gliders, where you could really give it some gas, even if it's a bit harder to fly, I don't need it because my flying style is so efficient for me that I still fly fast sections without always going full throttle.
Because you don't bank so much in between. You just fly the lines in a way that you lose very little altitude, and then you can fly them accordingly fast.
Exactly. And I've taken that from soaring—this choice of lines, finding the lines, and reading the terrain to see what possibilities are there. I can apply that very well to paragliding. Or, for example, flying under a cloud. So, soaring consists of "dolphin flight," where you fly very straight under a cloud and simply take your lift from the strongest part of the cloud. In paragliding, I do it exactly the same way. That means I don't just fly into any random cloud or cloud street; I'm really very selective and try to find and hit the best line under the cloud with the paraglider.
Are there things where you would say, you came from soaring, then switched to paragliding and did it more and more, but even with paragliding, your approach to flying changed a bit more over the years? And if so, in which areas?
For me, the wind has always become more important in paragliding. In soaring, I didn't pay as much attention to it during normal cross-country flight, but in paragliding, the wind is simply an essential topic. I've become much more attentive to what the wind is doing, which direction it's coming from, how to approach a slope so that you can get away safely, how you're always very low in terms of being towed with the paraglider or often inside the relief, how intelligently you build a flight path so that you find the right trigger point at the right place at the right moment. And I've become much, much more attentive to that. That wasn't necessary in this level of density in paragliding, but not in soaring. And that also distinguishes paragliding from soaring very strongly for me, because I'd say, the intensity of a three-hour paragliding cross-country flight,
...corresponds to the intensity of a ten-hour sailplane flight for me. That means paragliding is incredibly dense for me. It really challenges me.
So that means, even after three hours of paragliding, would you be as exhausted today as you were after ten hours of soaring?
So, physically and mentally? Yes, you could say that. So, a ten-hour paragliding flight is very fulfilling for me, but I'm empty at the end. And that also has to do with how I engage with flying. I go very deep into it and experience a flight like that very intensely. Gliding is relatively forgiving in a way. If there's a thermal cutoff or if the wind is a bit stronger, if there's no sun, you just fly 20 kilometers further to the next board. It's a bit fault-tolerant, I'll put it that way. But with the paraglider, we know that if the sun is gone or you make a mistake, or you're once in the rotor wind, you simply have a thousand possibilities of where you can end up on the ground. And that challenges my knowledge and my skills very strongly,
that you really have to push yourself. It challenges me, it fulfills me, it's just
intensive and dense. If you look at it that way, you could almost say that the really good paragliders might actually be better pilots than the sailplane pilots in the end? Given the performance standards they set for themselves? I mean, the
The performance requirements are... Well, a good paraglider could certainly be a good sailplane, that's for sure. But I've also seen some who were very good paragliders, started sailplane flying, and then couldn't really translate their paragliding skills over to sailplanes at all. So the expectations were very high, and in the end, relatively little came of it.
Because they couldn't really apply all the knowledge of micrometeorology and local winds and all that in soaring. Under some circumstances,
Yeah. Gliding is more of a heavy tactical game where you're constantly making tactical decisions on a large scale and, how's the best way to describe it, it's like playing chess and it depends much more on your overall tactics and your understanding of them.
And paragliding is like a mill, where you get caught in a dilemma and then find it really hard to get out of it at all, or what?
Sometimes, yeah. You sometimes have to really struggle. Of course, you also have the option of coming down very low with the paraglider very often, and then you don't have that off-field landing issue, which can sometimes be a bit complicated with a glider. Overall, paragliding, long-distance flying, is a very, very high art. So I admire everyone who does that and flies very far. It's nothing that's easy.
In an email regarding the preparation for this podcast, you wrote that you find debriefing after every flight very important. What do you mean by that? And how do you go about it yourself?
I've actually done that from the very beginning. I mean, I wanted to progress as a pilot, like when I started flying routes. And for me, it was essentially important to go through the entire flight again after every single one. I even wrote some of it down at times. In my early days, I wrote books where I analyzed the flight and wrote down what I did well, what I didn't do so well, and what could be done better. These are just learnings that you can write down. And then, when you repeat that, you integrate it and you can just do better next time. And that simply helps you move forward. And you have to address the bad sides. That means if you've had difficult or bad experiences, you have to look at them. Why did that happen?
And if you've had good experiences or successes, you have to look at those the same way. Or you can look at them and say, okay, I did that well. Maybe I can do it even better. Or I'm already very good in that area and I want to work on it further. It's really just about debriefing, self-reflection, looking back at what happened. And that's how you can develop. You can work on your personal performance and constantly get better if you want to. You
You just said that in the beginning, you mostly recorded a lot of things in writing. You really kept a book or a notebook or something. Do you still do that today? Or what does debriefing look like for you nowadays?
Yes, it has changed for me in the sense that my performance standards aren't as pronounced as they once were. But it's still the case that after every flight, the flight stays with me. That is, if I've done a big flight, I'm usually still occupied with it for two or three days. It's in my head. It's in my field. I still have to process it. I have to think. I'm happy about what happened. I think about what a beautiful situation it was. So, for me, it's not really about putting anything down in writing anymore, but it's a constant going over of the—for me, I tend to focus on the beautiful experiences—it just goes through my mind. And that's simply part of my post-flight processing, if you want to put it that way. It's just part of it for me.
I don't write it down anymore, but I'm still busy with it. I talk about it for a long time afterwards. And I almost always write something about it for my flights.
So when I submit something for an XContest, I somehow write down what I did or what happened, because I just enjoy replaying it, knowing what it was like. And I also like to look back at what happened five or seven years ago. I like reading what happened then. I enjoy that.
That's the post-flight review. What do you do to prepare for a flight? Yes,
Preparation is just as important to me. I'm someone who visualizes very strongly. That means, for example, if I'm going to South Tyrol or Stoderzinken and want to fly a large triangle, I usually go through the entire two or three-day trip in my head. I mean, I actually play out the flight virtually in my head. From the takeoff—actually, from climbing the mountain, from the preparations, from the takeoff. I then imagine how I'll board the first glider. I imagine what the flight plan is like. Then I visualize in my head, for example, making the first turn point at Chiemsee. Then I fly down to the south and I know exactly where I'll approach the mountain. I can, for example, when I'm telling you this, close my eyes and see the landmarks from my perspective.
That's how I go through the entire flight from start to finish in my mind. And in the end, it's like the flight often becomes reality on the day it happens. It goes so far for me that for my big flights, I know one or two days beforehand that I'm going to do them. That means if I had a Hilton, I knew one or two days before that I would fly it. My orientation was so strong, it was so deeply integrated into my mind, so visualized and so powerful and so real, that I didn't even notice it. I just knew it beforehand. And when I did my first 1,000-kilometer flight in the glider, I said to my wife, I said, "Honey, I'm flying that today."
There was simply nothing to it. That means it had already played out in me beforehand, and I visualized it and then just did it.
Powerful.
Yes, absolutely powerful. Sounds great. I'm sure many people would be happy if it were the case for you too, that you could just imagine it and then you'd get there.
Yes, of course. It does take some effort, obviously. It is, of course, my personal image, my personal model. I think it's totally important that everyone finds their own way in. That's my model, my vision of flying.
That's just my perspective. And it works for me. Of course, it's not feasible for everyone, but for me, it simply works and I've experienced it for myself. It fascinates me quite a bit as well, of course.
Well, you just mentioned the examples of Stoderzinken and Grente, where you've probably already flown relatively often. Stoderzinken is your home region. You might not know every mountain there, but you've probably flown over most of them at some point with glider or paraglider.
And now you're saying that you close your eyes and can already see the valley jump in front of you. How is it for you when you fly in regions where you say, "I don't know this place"? How do you experience those flights? Or how do you prepare for them?
That's relatively easy for me. I just have to go into a bit of detail.
When I started gliding at my airfield, there was relatively little knowledge transfer. That means I had to develop all my knowledge of where I was flying and my routes myself. It means I had to learn how to read maps and, for my part, had to account for the time of day, the position of the sun,
...bank angle, terrain, relief, and wind, and then I planned the long cross-country flights for myself and flew them without ever having flown into those areas before. And now, if I go somewhere else, it's relatively easy for me. I look at the maps, I look at the relief map, I look at the position of the sun, and if I say I want to fly from A to B now, my flight planning works basically the same way as it did when I used to plan my routes. I look at the maps, I look at the sun, and then I fly accordingly. And in the end, a large triangle, like the Storzinken or anywhere you fly to, is actually based on connecting the position of the sun at the right time and then planning your route accordingly.
And if you do it intelligently, you can fly good stuff almost anywhere to a large extent.
You've just been saying that you look at maps. That's a good segue to switch topics a bit. You're well-known in the scene, also for your company or the brand, or whatever you want to call it, Viento. And through that, you offer printed thermals and valley wind maps, both for sailplanes and paragliding, for the entire Alpine region. How did you come up with the idea that you need, or that the scene needs, such maps?
Well, I come from a time when cross-country flying still worked without GPS. That means there was no knowledge transfer via some online XContest where you can look at tracks; instead, there used to be maps—these were like insider-tip maps with thermal hotspots, flight lines, and how to best navigate dealers. It was simply specialized knowledge that existed back then.
Was, was was passed around under the table, so to speak?
Exactly, it was like a secret map where the best spots were marked. And yeah, maybe someone got that for someone else and explained it to them. For me, it was always like, I was looking for this knowledge and found it relatively hard to come by. And Simon Lämmerer, he's my colleague, he once started marking ideal flight lines and hotspots on the map. And I then helped create this map, and we did it with the idea that we just want to pass on knowledge. This is specialized knowledge, insider knowledge, it should just be available to everyone. And we just marked it out there. I then told Simon, I've already done some paragliding, and I said, actually, I want to capture all the valley winds, because it's just very important for paragliding.
And there aren't any proper documents, there are small maps here and there, but there's just nothing that maps the whole thing out correctly. So I started by taking this base map we have and dividing it into registers, into a grid, and on the other hand, I drew in the valley winds as they seemed logical to me, but on the other hand, I had all the valley winds checked and expanded by local pilots. That means, because I'm a NOBA team pilot, I had quite a few team pilots living in various parts, and I sent them excerpts; they then looked at all these valley winds and expanded and built them out.
And in the end, a map has come out with valley winds from Wiedern-Neustadt to Mont Blanc and from the Vosges to Slovenia. And it's all referenced and actually drawn out by local pilots. And my goal was simply to offer paraglider pilots an understanding of how wind systems work. So that you learn and see from the map,
where what kind of lee slopes are produced or where problems occur, where it's more difficult, where narrow sections create more or less wind. It should really be a tool for paraglider pilots to better understand the whole thing.
Now you're offering this as a printed map. From your perspective—I mean, you're selling it, so of course you'll say yes—but are printed maps basically still relevant today when the whole world is constantly on their smartphones or online somehow, everyone planning flights online with various XC planners and whatnot? So everything is done on a screen somehow. And now you come along with maps that are printed, which I'd then have to lay out on the ground next to me if I wanted to look at them at the same time. Why a printed map? Why not an online offer?
We've discussed that for quite a while. And there are actually several reasons for that.
So one reason, though not the most important, but one reason is that Simon and I, we come from—we're both graphic designers, we come from the print field. We just like printed things that you can hold in your hand. We like books, we like printed stuff, we like paper. We just like it when you have it in your hand, when you can grab it, when you can draw something in it, when it's just...
...what a map experience is like. Of course, it's not the most important thing, but it's part of it. The next thing is that we've mapped out the glider cross-country flight routes on these maps. And a cross-country pilot thinks in different dimensions. That means when a glider cross-country pilot plans a long distance, they talk about flying 300 or 400 kilometers in one direction. That means you have a map in front of you that shows the ideal of a very large area on the map. And the printed map gives you the view over the entire Alpine arc. That means you're much less restricted in your planning and your view of the Alps than if you have a small screen display.
That means this overall view of the Alps with the possibilities—for example, I can say I can do an Alpine cross-country flight from north to south and fly far to the west, or I have many more options if I can see the whole map at a glance. That makes the whole thing much more exciting. And the maps are also intended for training. That means if you're in training now and going through it with a flight instructor, the experience with a printed map, where you're sitting at a table with three or four people and discussing it, is much more intense, better, and denser than if you're going through it somehow on a monitor. That means it has a denser value. And the same applies to the Dahlwinde.
So you can simply understand the big picture much better when you have the broad overview. The digital versions also usually have the disadvantage that you can't display everything at different zoom levels. That means you can represent a landing field very well with small arrows and lots of content when you zoom in. But if you want to look at the big picture, it's technically very difficult to implement the level of detail we have digitally with the various zoom levels. And we looked into that and came to the conclusion that nothing comes close to doing it in print. And that was a conscious decision on our part.
We do it in print and we've used it that way. Our soaring maps aren't just thermic maps, but also foehn maps for north, foehn, and south for the glider pilot. And they naturally cover huge areas. When flying in foehn conditions, you fly from Virneustadt all the way into Switzerland. And that is really much better to grasp and understand with the big picture on a printed map. And with the Dahlwind map, it's like this: we used the back side so that we were allowed to include the Dahlwind chapter from Burkhard Martens for his thermic book. And that means, in the end, you get a learning effect because you have all the
...Dahlwind issues theoretically understand. Burkhard explains it really well with visual material and lots of information. And on the other side, you can cross-reference that simultaneously with what the map offers. That means, for us, it's simply the better, bigger picture, which just provides more possibilities.
You're saying that now with your trained graphic designer's eye, which you also use when looking at these things. Speaking of graphics, you also work as a graphic designer for Nova. There, you're responsible for, among other things, the new color design—or what I mean by color, the graphic design of the current Nova gliders. I believe that's been on the market in this form for two years or about a year and a half now. Did it come from your pen, or did you help shape it, as they always say? From a graphic designer's point of view, is glider design actually an exciting task?
Yes, it's absolutely exciting. On one hand, it's very exciting because the expectations for me personally were very high. So, when you're connected to flying as passionately as I am, the demand to do something good in that sector is naturally very high. So the pressure on me personally was high. I knew it was a very difficult topic. Paraglider design and colors is a very far-reaching subject where it's very difficult to appeal to a large number of pilots. It's a huge spectrum. So, I knew I'd probably face some headwinds there, but I'd also get support. It's certainly going to be a very hot topic. And
that was already very exciting for me. And it's also very exciting from a technical point of view, because a manufacturer's requirement is also that they have certain ideas, certain parameters that they orient themselves by. So with the NOBA, it was like this: they wanted to have relatively few sail cuts. That was supposed to work relatively easily. Then the problem is that the design actually has to work from a glider all the way to a high-performance wing. Every glider class has different requirements. A training glider has to work differently in terms of visibility during training than a high-performance wing. A high-performance wing perhaps shouldn't be built so extremely complicated technically. There are many technical frameworks running in the background.
The color selection isn't always that simple either, because you don't have just any colors to choose from. You have a certain spectrum.
The fabrics are also limited. Especially the modern lightweight fabrics are sometimes only available in four standard colors. That's basically all you can work with. Or you have to cut in a completely different fabric quality again if you want to say, I still want to have some orange in there, but that's just not available in the 27 Porsche right now.
Exactly. That's a huge topic. For example, I get a list of possible fabrics for every glider. And sometimes it's really complicated to actually do something that works. Because in the end, you're faced with the task of producing, for instance, three series colors that are as different from each other as possible, while still appealing to the largest possible audience of interested people and buyers. And that's not always easy to do with just a few fabrics. It's always a challenge. And in this day and age, it's even harder because the entire supply situation is even more complex. We now have fabrics for gliders that have a lead time of several years.
and you don't even know if the fabrics will be delivered. So it's a relatively complex topic. You might have to change a color at short notice again. It has to fit into the overall concept. So there are relatively many decisions in the background that aren't always easy to manage in the end. And in the end, it's also not easy to get this color distribution right, because you naturally need colors for certain divisions. How many colors do you want? How often do you produce which color? And of course, you might make a color combination that's difficult, which sells less. So it's always relatively difficult, but I'm happy, I mean, so far it's working well, the feedback is good and
we've hit the mark pretty well on the distribution and what ends up selling in terms of percentages. Of course, I'm learning, Noba is learning—it's a process, you can't just...
Two and a half years ago, I didn't know how far that would go, but by now I'm at the point where I know every fabric from every manufacturer, which fabric you can combine it with, and how it looks in the end.
At the beginning, I sat there with fabric samples, and the problem with paraglider fabric is the translucency effect—the effect when you have it lying on a table is completely different, or very different.
Partially, I think, the colors also come from the individual manufacturers; it says "yellow" every time, but then there's such a subtle difference, sometimes depending on whether it's the 40-gram fabric or the 32-gram fabric, or especially if you're combining something like Doctor with Porsche and stuff like that. You just have to say, yellow isn't yellow; you can see immediately that one is sort of a greenish-yellow and the other is more of an orange-yellow or whatever, and then you can't just make a completely yellow glider or anything like that.
Exactly, that's how it is, and it's also sometimes exciting because it's not always possible to make production colors 100% identical for display purposes; sometimes production colors are determined and fabrics are ordered that are simply
in reality. And that's sometimes exciting when you see the production models and then look at it and go, okay, does this actually work? And that was very difficult for me, or difficult for me, in the beginning. By now, of course, I have a lot of experience and I can say that it works and it's going to turn out fine in the end.
Well, a glider design should be as clear as possible in terms of being a recognizable trademark for a brand. At the same time, the sail shape is similar for many manufacturers. Also the goals, maybe to say, the gliders should look as stretched as possible. So I put narrow color bands in there or something. Certain structures always end up being similar. Besides Nova, which other brand do you feel has a successful design from your perspective as a graphic designer? Besides Nova, which other brand do you find, looking at it through the eyes of a designer, has succeeded particularly well in its own way—meaning they've pulled it off well?
Yes, it's special. I think it depends a bit on what the brand wants to embody and how the brand has done it right for itself. So, if I take BGD as an example, I find the entire color scheme interesting, and the direction they've taken and are following very consistently is, in my opinion, very good for BGD. I also find, for example... it's just different directions. I think even if it's a completely different approach, it's still interesting. So for me, everything is interesting; it doesn't have to be one specific thing that's right, but there are approaches that work differently and are still interesting. I actually find what Ozon is doing now with the new Zeno quite interesting.
I've seen that flying in Italy several times now,
What potential does it have with so few color combinations on the fabrics? Under certain circumstances, you can achieve something relatively easily, and I think Ozon has taken a step there that is potentially exciting.
Ozon had a graphic language before that was similar across all gliders, and this is a real break from that. I mean, with Nova you also made a real break, and many people will probably say, that's not a
Ozon had a visual language before that was similar across all their tents, and now this is a real break. I mean, with Nova you've also made a real break, and many people will probably say, "Well, that's not a classic..." Yeah, I've been self-employed since 1996. That means I've been in the design industry for a very long time, and the thing is, some things you develop from scratch need time before they actually work out in the field. And I have a nice example of that—a mental model or a point of reference for me—because of how advanced the new tent design was when it was introduced. Back then, Kriel Maurer had his X-Alps tent made in the old design. That means he made the X-Alps with the old design, even though the new Advanced tents in the new design were already available. And we thought, okay, that means the new Advanced design, which is very good, wasn't established yet; it was totally new, reduced... classic, real Ozon anymore, or at the beginning, many people probably also said, "Well, that's not a classic Nova anymore" and so on. Yeah, yeah. How hard is it then, especially with Nova, when you've arrived with a new design or your new design, how hard is it to convince people of it?
Yes, I've been self-employed since 1996. That means I've been in the design industry for a very long time, and the thing is, some things you develop from scratch need time before they work out in the field. And I have a nice example of that, a mental model or a point of reference for me, because of how advanced the new glider design was. Back then, Kriegel Maurer had the X-Alps glider made using the old glider design. That means he made the X-Alps with the old glider design, even though the new Advanced gliders in the new design were already there. And we thought, okay, that means the new Advanced design, which is very good, wasn't established back then; it was totally new, reduced
and actually, for some reason, Kriegel Maurer couldn't settle for them back then. And now it's completely established and no one thinks it would have been better in the old design. And I believe it will be the same with this one, and basically with Nova too, it's now established, it's seen often, it works, and people understand it, but in the end, it sometimes takes time for it to trickle down and be understood. Yes, and that's how it is. There are some people who say, "that doesn't suit me" or "I don't like it" or "the shapes are bad," but you just have to live with it and deal with it, that's just how it is. You can't get 100% buy-in, that's always difficult, but we try our best.
Let's jump to a completely different topic. You were in Iran a few months ago with some people from Nova. How did that happen?
Yeah, that's a long story. So Thermik Broschardt was in Iran, I think six or seven years ago, and he made a video back then and told me how cool flying in Iran is. And I told him at the time, "You know, Mick, if you go to Iran again, I'm coming with you." And then this year, it just happened to work out that Thermik went down again and we had the opportunity for a small group to go down. It's not that easy. You can't just put out a big call. Only four people were possible, and in the end, it was a small group with Mick, with Dil Gottbrat from Nova, the Nova BR guy.
and Burkhard Martens was with us. So there were four of us who more or less set off on this expedition. But we had a contact down there—that was Hamed and Afshin. They are the Nova representatives down in Iran, and Fatemeh and Mohamed, who do Skywalk and Advance sales in Iran, they actually looked after us. Yeah, and in reality, having someone look after you down there is very important. I mean, you can't just fly down there and say, I'm flying down there now. It's not quite as simple as it is here.
What kind of impression did you get of the paragliding scene in Iran?
Yes, that was extremely surprising for me because
I think the West, or many people, have a bad or distorted image of Iran. And the truth is, the Iranians themselves are actually, first of all, incredibly nice, helpful, and insanely loving people—truly, insanely loving people. Not fake, but they are genuinely exceptionally nice. And the paragliding scene down there is very active. That means they have an incredibly large number of paragliders who fly a lot in very many flight areas and have really good gear. So it's not like you imagine, where they fly with some old rags and don't have good equipment; they have top-tier gear. They have all of that and they fly very well, too.
So, regarding the training standards, how it works down there exactly—we saw schools that were quite consistent with their training, but I don't know which specific training scheme they use. But from what I saw, they fly very well, they have very good pilots, they have very good performance pilots, and top-tier gear. So it's fascinating.
How many of you came there to fly, or was it more of a "business trip" and networking trip, where it was more about the human element or the business side and not so much about actually getting into the air?
So we flew quite a bit, not huge flights, even though the terrain allows for it, but we visited several different flight sites and that was the goal. We wanted to see multiple sites, and of course, we wanted to see something culturally as well. Flying was important, but Iran itself has so much to offer culturally. You honestly can't stop being amazed. It's really like One Thousand and One Nights. It's an incredibly beautiful country, apart from the flying. Yes, we flew to different flight sites. Of course, down in those desert areas, as I said, the conditions are already very exciting. That means you have base altitudes there...
four, four and a half thousand, you get up relatively quickly. There are days where it reaches six thousand meters. They fly four hundred kilometers down. It's strong thermals, dry thermals, sometimes harsh thermals, so in the desert areas, there's nothing where you as a beginner should go. But then there are northern areas, which are rather green, like back home. That's by the Caspian Sea, that's more like when you fly in the Alps. It's calmer there and there are super beautiful areas where a lot of people fly. There's Ramian, that's a flight area, it's like the Alps. It's like green carpets laid out. There's a shuttle transfer up there. There are 50 people standing up at the start, from the beginning to the aerobatic pilot, to the cross-country pilot.
They're out there all day. It's unbelievable. You wouldn't believe that there's such a vibrant scene in Iran.
Are it mainly men flying there, or are there women too? Or is it, because it's Iran—where people say it's a very male-dominated sport—perhaps even way more than here, where the female quota is very low?
So, I was fascinated. For my purposes, there are actually very many women down there who fly. Of course, there is more or less a headscarf requirement for women. So not the burka, but a headscarf. And the headscarf for the typical paraglider lady down there is just some kind of paraglider manufacturer's buff they have on their head. And then the helmet goes on, and in reality, well, they are very relaxed about it. And there are many women who fly and are recognized and from the heart, and I never had the feeling that the men somehow dominated or treated the women worse or anything like that. Rather, they were full members. Flight is flight—the community accepts them and they fly very well, and they were incredibly lovely experiences.
And they are so warm, they talk a lot, and they speak relatively good English. It's just really a great community. But you have to say one thing: paragliding in Iran is actually a sport for the rather wealthy. That is, the paragliding equipment costs just as much as it does here. There's nothing out there that's much cheaper. But the wage level of a classic employed secretary is, of course, already very, very low today. So, for a normal family, normal working people, whether they can afford paragliding, I would say rather no. There are very many dentists, dentists, doctors,
who do it, or rich kids. So, it's a bit of a shame, of course, but that's just how it is.
Is it seen as an elite sport there in the country as well?
That's hard for me to say. You could imagine it, under certain circumstances. But there are regions that don't know paragliding at all. They told us that if we fly cross-country and land somewhere further away, we might land in areas where they've never even seen a paraglider. So, it's not like,
as public as it is here, that everyone knows about it. I mean, Iran is huge. You have to imagine it like this: there are regions that are very rural. And if you come down there with the glider, they just, yeah, they don't really know them.
Based on the experiences you had there, would you say in retrospect that Iran is suitable or even worth it as a paragliding destination or even for cross-country flying? Or is it already so exotic that as an individual traveler, you don't stand a chance at all, really?
Well, I'd say it's not really for individual travelers. Of course, you can go to a well-known flight area like Ramean and fly locally. Cross-country flying is a real challenge. Because, when we were down there, it was like this: we were looked after by our Iranian friends and we always flew together. That means if we landed somewhere outside of the launch site, there was always an Iranian with us. Because there are several issues. One is that you might land in an area where there are people on the ground who don't speak English and who call the police relatively quickly. And, yeah, and that's relatively difficult. You just can't communicate with the police sometimes, and that is,
And of course, there are areas in Iran that are sensitive. That means there are military facilities in Iran that you wouldn't recognize from the air. To give you an example, we flew from Rock towards Ifshaan, which is about 50 kilometers away. We landed there because Mohamed flew with us and he did a spiral descent. Burki and I flew with him, landed there with him, and he said, "Okay, if we had flown another 20 kilometers, we would have hit a restricted zone where we aren't allowed to fly." Two months after we got home, I did some research and found a report about the Iranian nuclear plant, and the location was listed there. I realized that the Iranian testing site was just 20 or 30 kilometers away from where we were.
And if you fly there freely, just flying around and landing in that area, then it's over. You'd have a really big problem. We weren't allowed to take cameras with us while flying either, because if you take photos in the air and accidentally photograph a military facility—which you can't see very well from the air—then of course you have a problem when you land and the policeman starts checking your photo equipment and you have a photo of a military facility that he recognizes; I'd say then you have a massive problem. And that just makes it very difficult. That
That means there are no YouTube clips of your flights either, because you didn't have a GoPro on your helmet or anything like that. Exactly. Where you could have captured it.
Exactly. But it was like, Hadi,
That's from the trip with a man who flew with us and took photos of us. That means there's footage of us flying, Burki and I, photographed by Hadi. And that's coming out—there's going to be a report on it and there will also be pictures, almost fantastic pictures. I mean, when you fly over a desert landscape at four and a half thousand meters, where there's the great plain and the mountains grow out of the ground, and you're flying in very dry air in this surreal area, it's incredible. I've never flown in such an exciting area before, in terms of flight conditions and visually. On the horizon, we saw salt flats,
they looked like fog lying in a valley and incredibly large plains. Insane. So, the visual impressions were incredible. And you could fly crazy distances down there. But the conditions are such that if you're a very good pilot and you could maybe fly 300 kilometers down there, which is certainly possible for a good pilot, you'd actually, in my terms, need an Iranian next to you flying with you who then lands where you land. Because otherwise, it could get complicated.
Or
you try to fly long distances with the tandem and you always have an Iranian sitting in front of you saying, you're my interpreter and the one who has to find the thermals again, no matter where I land.
Sometimes, yeah. It's a real shame because the country has incredibly cool possibilities. You could fly routes there endlessly.
But I think it's just not ready for widespread travel yet. You need support on the ground. In Isfahan, for example, it was like this: the Iranian, Hamid, who basically signed off on the NOBA distribution for us, was there for us, and that was basically our guarantee. He accompanied us. So it's not as simple as just driving there and flying. It's not easy. It's even the case that if you apply for a visa, you need a visa for down there. It's not guaranteed that you'll get an approval, that you'll get a visa to enter. It could be that you have some weird bad luck and they don't let you in at all, under certain circumstances for some reason. It's not quite that simple.
That's the funny thing. Once you're in the country, the Iranians actually live very freely in their thinking and their actions. They are totally free. They know there are certain areas you have to be careful in. You have to watch out for that knowledge. But outside of those areas, they know very well what they can and are allowed to do. And they actually live incredibly freely. Freer than we are in some areas. It's almost hard to believe, but that's how it is. They live a very, at times a very carefree, cool life. Which might be hard to understand right now, but it's really like that on the ground, to be experienced.
That means there are fixed rules, but within those rules, there are enormous freedoms.
Yeah, actually they do. They know how to handle it. They know how to work within these frameworks. And within those, when they play this game, they can just exercise incredible freedoms that are even exciting for us in terms of what they can do. But they live incredibly differently.
Fatima told me that normally you're not allowed to fly at all in Isfahan. This city is just off-limits. But then there's some revolution leader, I don't know, a holiday. And if you apply then, you can suddenly start and fly right in the middle of Isfahan, in the middle of the dry riverbed, inside the city, with the trike, with the paraglider—things you're normally never allowed to do. But if you know how to do that, you can just do things that are normally never possible, which wouldn't be possible for us either. It would be like if you said you're going to Munich and somehow you can just fly right in the middle of the city because, I don't know, the mayor is having a birthday.
They just create these certain loopholes. Or take Fatima, for example—actually, it's not really allowed for women in Iran to ride motorcycles. They're allowed to go paragliding, but riding a motorcycle is difficult. Yeah, and they ride them anyway. She wears the motorcycle suit and just rides anyway. She just does it.
If you imagine it here, like you just go out riding somewhere, without a license, without anything, without permission, but they just go ahead and do it.
Because they just want the freedom.
Yes, exactly.
Werner, now towards the end, you can tell me one more story. Let's jump back from Iran to the Alps. I heard you're something like the inventor of the so-called Stoderzinken triangle.
What's behind it? Well, that's a bit of a long story. After I stopped sailplane flying, I somehow looked for a connection in the community, in the paragliding community. And in our area, there's a Lex Robet, who is actually quite well-known, the paraglider. He was already very good back then. And I met up with him at the time because he simply wanted to exchange ideas on how paragliding works, how it works for us there. Just connecting from sailplane pilot to paraglider.
And Lex and I were talking back then, and that was the first time we really talked about Dalvin. And I told him, Dalvin, yeah, okay. And he always said, Werner, you'll see, when Dalvin strikes once, then you'll know what I'm talking about. And I said, yeah, okay. But I knew very soon what was going on. We then talked about routes. And of course, because I had flown so far in soaring, I talked about cross-country flying, even though I hadn't actually flown any cross-country routes with the paraglider at that point. And we talked about triangles, about FE triangles and what's possible in the area—that you don't just fly on the ridges or to South Tyrol, but in our area. And I told him about the Stohler Ziegel back then, I looked at the thing, the starting point,
And I then, in Lex, took the XC planner back then and, using the knowledge I have as a glider pilot—how I can read the landscape—I thought, okay, you could actually fly 200-kilometer FE triangles there. And I mapped that out in the XC planner back then. But I flew cross-country routes myself. And I sent that to Lex, and for him, it was still difficult back then, because you have to imagine, you're coming from the Dachstein
didn't actually fly west. That means it didn't happen back then. The assumptions, the beliefs, they were just like, you can't go there, the valley wind is too strong, you can't do it properly, no one has flown there yet, it won't work. And I just drew that in with my lack of knowledge, but glider pilot knowledge, or lack of knowledge of paragliding, I just drew that in. And in the end, that's how the 200-kilometer FE triangle came out, and that's actually now the basis for the FE triangle that is flown from Schlotterzinken, where they're actually already flying 300 kilometers now. And it's still based on that one idea that I sent in Lex and worked out back then. And Lex and I flew it first, but we expanded it right away; we didn't fly 200 kilometers, we flew 250 kilometers straight away on the first attempt.
and we basically established the FE triangle, and now it's actually 1,000 kilometers in Austria outside of the standard triangles, where you can always, in good weather, fly 200 kilometers right away, but also up to 280, 300 kilometers. And that's based on that assumption from back then.
But does that still mean the Schlotterzinken Triangle and not the Louis-Dolt Triangle?
No, no, of course not. There were some suggestions, someone wrote about the Louis-Dolt or Werner triangle, but in reality, I mean, it doesn't need to be.
And what great route did you see today? Do you still have any in the back of your mind or on your radar that you'd like to fly again?
Yes, I have several ideas. I'm really into destination flights—one-ways, specifically, I find those particularly appealing. I have a few ideas. This year, I flew from Meduna almost all the way back home. That's relatively unusual. And I'd like to fly from my area down to Meduna sometime. That's also unusual, I think that's pretty cool. Then I'd like to head from here to Weiz, which is near Graz. I'd like to fly there to my grandson's place and land at his house. It's not far, about 150 kilometers. Technically quite difficult. I'd love to do that. Or I'd like to fly from my place, from Stuttgart-Hinten, into the Engadin. That sounds far now, but it's about 250 kilometers.
With a slight easterly position, that's absolutely doable. I'd follow the route that I've actually already done with the glider.
If there are 200 kilometers, you can give it a try if it's easy. But I'm actually getting in my own way a bit, because I don't really need to fly that far anymore or I don't want to anymore. It's still appealing, but the maximum focus isn't really there anymore. Of course, that doesn't always make it easy to call it up on day X and actually fly it. But we'll see. If I'm in a good mood and think I'm feeling good, then maybe I'll do it.
Yeah, probably the day will come when you know two days in advance. The day, the days come, tomorrow or the day after, that's the day I'm flying from Stoderzinken all the way to Engadin.
I assume so.
Werner, let it be so.
Yes, thank you.
Thank you for these very interesting stories. Not quite around the world this time, but you've checked out many different topics. It shows what a great, very diverse aviation life you've already had and probably still have. Thank you for this account. Thank you very much. And all the best.
Thanks. I was very happy to do it.
That was Werner Luidold in conversation with Lucian Haas. You can find some further links to the topics discussed in the show notes for this episode on the Gleitschirm-Blog Lu-Glidz. I deliberately run Podz-Glidz and Lu-Glidz without ads and without a paywall. However, both involve some costs and, above all, a lot of work that needs to be financed somehow. In other words, I also rely on your help to be able to produce many more podcast episodes. As a supporter of Podz-Glidz and Lu-Glidz, you remain completely free. Because there is only one simple rule: you can give as much as you want. This can be a one-time or a recurring contribution. You decide. If you're still unsure about what amount might be appropriate, I have a non-binding suggestion here.
See you next time. Ciao.
By the way, I'm always looking for other interesting conversation partners with noteworthy stories from the world of paragliding. Do you have a suggestion? Then tell me about them and, if possible, send me their contact details right away. Best sent via email to blueglideskontakt at gmail.com. See you next time. Ciao.