Planet-Soaring

The Li-Ion Revolution: Why I’m Ditching My LiPos for Aeromodelling !

2026-06-29T17:04:12.179+02:00

Aeromodelling has benefited from the advent of electronic cigarettes and, more recently, the rapid advancements in electric vehicle technology.

I would like to share a new product I recently discovered that should effectively replace my LiPo batteries in many situations.

These are Li-Ion batteries with extremely low internal resistance, allowing for an incredible continuous discharge rate of 70A in the 18650 format. For comparison, a Sony-Murata C6 cell is rated for 30A, while other brands generally do not exceed 10A.

To illustrate the advantages of these new batteries, I’ll use two personal examples:

My ASW-17 FW: I currently use a 6S 2800mAh graphen LiPo weighing 361g—the lightest option I could find for this capacity. If I switch to a 6S 3000mAh Li-Ion setup, I gain slightly more capacity while reducing the overall weight.

My Electro Quantum 3 (F3G): The energy density here is very impressive. Typically, models of this type use either a 3S 1800mAh pack (my current setup) or a 4S 1300mAh configuration (using two 2S packs, as a single 4S pack is often too wide for the fuselage). By switching to Li-Ion, I can increase capacity to 3000mAh for the same weight in the 3S configuration, or more than double the capacity in the 4S configuration with only a negligible increase in weight.

Consider the capabilities of these batteries: they can deliver a continuous 70A (with peaks of 150A), can be safely discharged down to 2.8V per cell to utilize their full capacity, are rated for 800 cycles (a conservative estimate), can be stored fully charged (ideally at 4.1V per cell), and—unlike LiPo batteries—do not swell. I find the offer really appealing!

Also, unlike LiPo batteries—which are still essentially handmade (due to low production volumes) in just three factories before being branded and sold by dozens of different companies—Li-ion batteries are manufactured on automated, robotic production lines. This ensures consistent quality from one cell to the next.

When it comes to safety, Li-Ion chemistry offers a massive advantage over LiPo: puncture resistance. LiPo batteries use a soft polymer pouch that is easily damaged in a crash, often leading to spectacular thermal runaway and fires. In contrast, 18650 Li-Ion cells are encased in a rigid, heavy-duty steel cylinder that absorbs shocks, vastly reducing the risk of accidental combustion. Furthermore, they are chemically much more stable, making them far safer to store at full charge inside your home or workshop.
Noro-Ion batteries come in three cell sizes and are assembled using silver solder. More products with even higher energy densities are expected to arrive by the end of the year.

I’ve seen the assembled batteries, and I have to say the result is incredibly neat and impressive. I spoke with my friend Philippe Lanes, who already uses these batteries in a Baudis GP15 (6S, I believe) and an Aviatik Composites Falco (3S); he told me the performance is amazing in terms of handling and runtime, with a single pack easily lasting through an entire afternoon of flying.

For batteries with an odd number of cells, a 1g spacer takes the place of the missing cell, allowing the packs to maintain the visual appearance of an even-numbered configuration.

As for competition, I can't say whether competitors need 3000 mAh capacity for F3G...

Of course, an inline 2S battery would work fine for an HV receiver setup, though it might be a bit overkill.

Anyway, I’ve ordered my packs from the website (https://www.noro-ion.com/) and am expecting delivery in the next few days. I can't wait to try them out and will keep you posted!

A quick mountain outing to escape the heatwave

2026-06-29T08:24:43.813+02:00

A quick mountain outing to escape the heatwave once again. I met up with a few club members at the Col du Joly (2,000m), facing Mont Blanc. Conditions were rather light, with some nice thermals but also significant areas of sinking air that sometimes required using the motor to regain altitude. Naturally, the photo session focused on Mont Blanc, involving passes behind the slope to capture Europe's highest peak in the background.

(Photo credit: Joël Marin & Pierre Rondel)

French F3F Team 2026 Raffle !

2026-06-25T14:27:40.614+02:00

The 2026 French F3F team is organizing a big raffle to help finance its trip/stay at the F3F World Championship. Whether you practice slope soaring for leisure or in competition, this raffle is an opportunity for everyone to try to win one of the superb prizes generously donated by our sponsors !

Rollin Composites
MKS servo
KAVAN-RC
Revoc Custom
ServoRahmen
Aufwind Magazin
Prodij HM Rémy Sorba Expertise : sorba.expertise@gmail.com
FAC imprimeur

You will find a detail description of the different prizes here

https://www.facebook.com/TeamF3fFrance2026/

And, you can buy tickets following this link:

https://www.papayoux.com/fr/cagnotte/raffle-f3f-team-france-2026

Please don't forget to speficy the number(s) you choose, given that remaining ticket numbers are the following:

4, 8, 10, 29, 30, 32, 33, 35, 38, 39, 42, 45, 48, 49, 51, 52, 58, 61, 62, 64, 65, 66, 71, 75, 79, 80, 81, 82, 88, 89, 92, 93, 94, 97, 99, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 116, 117, 119, 120, 122, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 139, 140, 143, 145, 146, 148, 149, 150, 151, 152, 154, 155, 156, 158, 159, 160, 162, 163, 164, 165, 166, 168, 172, 175, 176, 177, 179, 180, 181, 182, 184, 185, 186, 187, 188, 189, 190, 191, 192, 193, 195, 196, 197, 198, 199, 201, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 213, 214, 215, 216, 217, 218, 219, 220, 222, 223, 224, 225, 226, 227, 228

Juno 2 from SansiBear, the MicroMax version XL !

2026-06-25T07:33:26.632+02:00

I absolutely loved the Micromax when it came out—it was a real "unicorn" of a device, packed into a pocket-sized format.

So, when Christophe offered to sell me a Juno 2 kit, I didn't hesitate for long. The package arrived a few days ago, and today I’m sharing the photos I took this morning.

Let’s get to know the Juno 2! The Juno 2 is designed to be the ultimate middle-weight "Slopestyle" sailplane—built to handle everything from cruising in light winds to performing aggressive aerobatics and some dynamic soaring (DS).

Design: A Team Effort

The initial concept and philosophy behind the glider come from Henning Plemo Schmidt—aka SansiBear—who champions a "SlopeStyle" approach to slope soaring rooted in pure enjoyment. The 3D design work was handled by Roland Berlinghof.

Finally, while the model retains the wingspan and tail configuration of the original Juno, the all-new airfoil was designed by Christophe Bourdon (who also created SansiBear’s highly acclaimed microMAX). The airfoil transitions from a thickness of 8.1% at the root (leaning towards an F3F style) to 5.8% at the tip, making it better suited for wide-angle maneuvers. The microMAX’s V-tail has been replaced by a conventional vertical fin and a high-mounted horizontal stabilizer with an elevator.

Construction

The "Black Final" Layup (CW80/160): Only one layup is offered, but it is designed to satisfy all riders. The fuselage is constructed from heavy-duty 160/205 Carbon Leinen (with fiberglass in the front section to ensure radio signal transparency). The wings primarily use a 80g BiAx carbon layup paired with a 160g carbon D-box for massive torsional stiffness.

Flight Characteristics

The core philosophy of the Juno 2 is versatility. The unique carbon layup achieves a perfect weight-to-strength ratio:

Light Air & VTPR: It is nimble and light enough to glide smoothly in light slope conditions or indulge in casual, low-altitude aerobatics (VTPR style).
Speed & Heavy Slope: It is incredibly rigid and structurally strong enough to be pushed hard on fast mountain ridges, including carving out several "between-the-lines" Dynamic Soaring (DS) laps.

Kit Overview

Here’s a quick look at the kit I received.

It comes with covers that seem rather fragile but are nonetheless essential given the glider's black color.

The wings look great with their carbon finish, even though I’m not a huge fan of black or exposed carbon over such large surface areas.

Beyond their good looks, they are lightweight and show excellent flexural rigidity—tested by resting the glider on one wingtip and lifting it by the other. The servo bays are shallow, especially for the ailerons; 8mm or 9mm servos are the best choice there, whereas 10mm servos fit easily for the flaps. I haven't decided on servos yet; I might actually use 10mm servos for the ailerons and fabricate a custom cover with a slight bulge to accommodate them. At the wing root, you have 2 ballast compartiments (1 front and 1 rear to the joiner) with a dimension of 10mm x 20mm and a lenght of 150mm.

The Joiner looks strong and with a foam core. As an option, I got a very special steel joiner of 639gr that can receive 2 brass ballast of 124gr each.

The fuselage is also beautifully finished. The nose cone insert needs to be cut out to house the radio gear. It is 21cm long, but the internal volume is sufficient to mount the two elevator servos side-by-side, as well as 18650 battery cells for extended flight time.

The control linkages use carbon rods. The rudder is hinged with fabric, and tape seals the open side. The elevator linkage is unique: a carbon part holds a flat carbon strip that connects the two elevator halves. The only downside is that the carbon part floats freely inside the fuselage, so a small hatch allows you to reposition it if necessary. The tail assembly is also very light, weighing in at just 33g. This is a key detail, as it means less nose weight is required for balancing.

Finally, there is a small accessory bag containing the cables and green MPX connectors—already soldered—along with M2 metal clevises. Plus, two cool SansiBear stickers.

Below are the component weight:

Right Wing 355gr
Left Wing 348gr
Fuselage 270gr
Joiner 90g
Tail 33gr

Technical Specifications

Wingspan 2490 mm (~2.5 meters)
Length 1300 mm
Takeoff Weight ~1680g (depending on your electronics setup)
Wing Area 44.36 dm²
Tailplane Area 4.75 dm² (Elevator) / 3.0 dm² (Rudder)
Airfoil Thickness 8.1% tapering down to 5.8%
Airfoil Design Christophe Bourdon
Manufacturing 100% Made in the EU
Build State ARF (Almost Ready to Fly) — includes pre-installed wiring harnesses with MPX plugs.
Price: 1198 Euros
https://sansibear.de/product/juno2/

This first look suggests that the quality-to-performance-to-price ratio is excellent at the advertised price. Of course, we’ll see how it performs in the air, and I’m really looking forward to that.

Let's start the Assembly !

F3F in Lavender Country!

2026-06-08T08:56:04.885+02:00

This stage of the French F3F Cup is always a pleasure, offering a chance to rediscover the landscapes and scents of the Southern Alps, even if the lavender isn't in bloom at this time of year.

Eighteen pilots gathered at the foot of Mont Ventoux, the region's iconic mountain, at 1910 meters, for two days of sunshine.

On Saturday, we met at 10:30 a.m., drove to the flying site, and prepared for the race. The wind was still light but was expected to pick up when the sun hit the valley. After a briefing from the organizer, Philippe Lanes, we started flying around noon and completed eight rounds in rising but still very variable conditions. The wind gusted between 4 and 10 m/s, and the gliders flew either empty or ballasted up to 2.8 kg.

At the end of the first day, Pierre Diatta was leading the race. Behind him, the points were tight and nothing was decided.

On Sunday, we resumed racing late in the morning on the same slope. The conditions were still very variable, and in this game of "who benefits from the best conditions," Roland Henninot came out on top, piloting his Wasabi 2 perfectly to seal the deal in the last four rounds, for a total of 12 rounds over the weekend. In second place, I wasn't as lucky as Roland and tried to minimize the damage to avoid losing too many points. The last round finished me off with very low lift conditions, forcing me to dive to maintain some speed. I wasn't the only one to suffer from this variability; Pierre Diatta finished just off the podium, while Philippe Lanes snatched third place.

Our two juniors performed admirably in this competition, gaining valuable experience in managing altitude gain and adapting trajectories to the prevailing conditions.

All in all, we had a fantastic weekend together, topped off with a delicious meal at a great restaurant on Saturday evening. A huge thank you to Philippe Lanes for the organization, Joël Marin for the timing logistics, and the launchers and launchers.

See you soon for the next round of the league!

Full results: https://f3xvault.com/?action=event&function=event_view&event_id=4224

F3F RC-Network FAI Vosgen

2026-06-03T09:28:36.547+02:00

Back from Alsace, where I spent three days with 40 pilots from Switzerland, Poland, the Czech Republic, the Netherlands, Germany, and France for a round of the Eurotour/F3F World Cup, the RC-Network FAI Vosgen.

Friday, the competition got off to a good start after the briefing around 10:00 AM. We were at Battriekopf, and the conditions were quite good. We completed five rounds in conditions that became increasingly soft in the afternoon. We stopped flying around 5:15 PM, as the lift became a bit unpredictable.

Saturday, we met up at Schweizel for a day of free flying. The wind, very light, kept shifting. Around 2:00 PM, the organizer decided to declare the day a "Day Off."

Sunday, we met at 9:30 AM on the Schweizel slope to try for more rounds. We completed the first round, but were forced to interrupt the second round as the weather was becoming truly threatening, and it wasn't safe to remain exposed without shelter as the storm and rain approached. The radar echoes clearly indicated that we were going to get soaked!

The organizer initially decided to return to the parking lot temporarily, but ultimately decided to hold the awards ceremony as the weather wouldn't allow for flying again in the afternoon.

The awards ceremony was cut short as the downpour intensified.

Markus Meissner (Switzerland) took third place after a strong final round. Simon Eggimann (Switzerland) finished ahead of him, and to prevent our Swiss friends from dominating the podium, I won this edition of the RC-Network FAI. I didn't win any rounds in the competition, but I managed to minimize the damage in the poor or average conditions and achieve respectable results when I had relatively good ones. I flew five rounds in Odin and one round in Wasabi 2, with flying weights ranging from 3.2 kg on Friday to 2.7 kg at the lightest.

This competition remains a highlight of the season due to its central location in Europe. A huge thank you to Jacky Kugler, Tobias Reik, and the entire organizing team. The atmosphere on the slope was fantastic, the region is beautiful, and the food is amazing—to top it all off!

See you soon for the rest of the season!

Full results: https://f3xvault.com/?action=event&function=event_view&event_id=4106

Photo album on Google: https://photos.app.goo.gl/cSmf8wzqMgg9JY3F7

Battery connector with balancer plug

2026-05-19T07:40:52.392+02:00

A quick look at the battery connections on the ODIN. Until now, I've been wiring my 2S Li-Ion batteries with a main JST connector and a servo connector acting as a balancer, which I use with an adapter to connect to the charger. But most of the time I don't balance my batteries (which I charge to a maximum of 1Ah), or maybe only once a year. In 2025, I started equipping my batteries with a more secure XT-30 connector.

And then recently, I discovered a new MR-30 connector format which, for a slightly larger size, offers 3 pins. So a single connector for both power AND balancing—perfect! As for the charging cable, which now has 3 wires, you have to bridge the positive and negative wires on the XT-60 connector on the charger side to add the center tap and then connect everything to the balance connector. We'll see how it goes in practice, but I find this new connector very interesting.

A French F3F championship amid strong winds and showers !!

2026-05-18T22:33:56.555+02:00

(Photo Credit: Joël Marin & Pierre Rondel)

31 pilots met near Limoux for the French F3F Championship. It had been a long time since we'd had such a large turnout for a championship, so it was great to see so many of us!

However, we knew the weather would be challenging as the forecast predicted heavy rain, but fortunately, three days of tramontane winds were forecast, so we were able to fly to St. Ferriol with our cars parked nearby, provided the access road was passable.

On Thursday around 11:15 am, Andreas held the briefing with the usual information. The competition began at 12:00 pm. The conditions were challenging, with wind gusts reaching 20 m/s and dropping to 10 m/s or even below a few seconds later. We completed five races in these variable wind conditions, with one or two interruptions due to rain showers. We finished around 6:30 pm.

Friday was predicted to be the worst day according to the weather forecast, but since the road was dry, we rushed to the slope to stay there for the day. It was going to be a tough day for both the equipment and the pilots. The landing caused a lot of damage, and the frequent downpours meant we regularly had to take shelter and protect ourselves. The wind and humidity made the cold quite noticeable.

Despite everything, we managed to complete five more rounds, but some pilots had already withdrawn, having damaged their gliders and not wanting to risk another one on subsequent flights.

On the competition front, the battle was fierce, especially among four pilots: Sébastien Lanes and JB Deguelle, who were flying on their home turf, and Matthieu Mervelet and myself, who came to challenge them on their own turf! While I was in the lead on Thursday evening, Sébastien made a great comeback and took the lead on Friday evening. Behind him, JB and Matth were fighting to reach the third step of the podium, or even higher!

We ended the day around the table (we are in France, after all!) sharing a good meal and chatting.

The last day, which was supposed to be the driest, played a nasty trick on us. During the night, heavy rain made the road impassable. We met at the St. Ferriol village hall to wait and look for a solution while the few pilots camping there flew in excellent conditions—frustrating!

Finally, around 11:00 AM, Andreas proposed a backup plan: park in a field after the first 200 meters of the road, before it became impassable, then walk up the slope—an 8-minute walk at most.

Around noon, the course was ready, and we could resume the competition. The 5 rounds required to use a second joker were unrealistic, so we did 3 more rounds, bringing the total to 13, which wasn't too bad. I couldn't gain any points on Sébastien, who was still incredibly sharp in his piloting. Meanwhile, a fierce battle raged between JB and Matth for third place. Matth reached the podium in the 12th round, but JB overtook him again in the 13th and final round – what suspense!

It's worth noting the excellent performance of our two juniors, Antoine Darries and Thomas Mervelet, who didn't let the strong winds get to them. It's great to see the next generation!

Congratulations to Sébastien Lanes, who reclaimed his French Championship title after entrusting it to me last year! I finished as runner-up and am satisfied with my performance. JB Deguelle completed the podium for this 2026 championship.

In the end, a great championship with some fantastic flying, with Jean-Luc Foucher achieving a best time of 31.98 seconds.

On the glider side, the one that really caught everyone's eye was the new ODIN, produced in France for Rollin Composites. It made a very strong impression in the hands of pilots like Allan Cohen, Matthieu Mervelet, JL Foucher, JB Deguelle, and myself. This glider is clearly a winner, boasting numerous qualities and top-notch performance. We'll be keeping an eye on it at the upcoming competitions.

A huge thank you to Andreas and the entire organizing team for this fantastic championship. It wasn't a sure thing given the forecast, but they pulled it off, so congratulations! A big thank you to the contest directors, the buzzmen judges, and the launch team—without you, there would be no competition!

See you soon on the slopes!

Flyin the Odin

2026-05-12T07:26:00.001+02:00

A few F3F race laps with the Odin flying empty, in light lift conditions. This allows to see how the glider behaves and retains its energy and speed.

Odin Assembly

2026-05-11T07:26:00.003+02:00

After the first flights of the Odin, I'm finally back to discussing its assembly. Nothing particularly special about the assembly, but a few tips and precautions. I decided to mount the elevator servos at the front rather than in the rear boom. The fuselage cross-section doesn't allow for the installation of traditional 12m servos. I had to switch to MKS HV 6100 servos, which are smaller and, more importantly, shorter. They fit perfectly. I designed and 3D-printed a servo tray in carbon PETG. The elevator control linkages are already finished on the tail end; you just need to glue a threaded metal rod to its end to accept a clevis. I used MPJET plastic, which I've been using for years with complete satisfaction. In the wings, I installed the LDS servo room and used HBL 6625 servos for the flaps and HBL6625 mini servos for the ailerons. If there's room for the flaps, the wing's thinness means the 10mm servos just barely fit at the ailerons, and they need to be moved towards the spar to gain a little more clearance.

The green connector, once wired, is glued into the fuselage between two 1mm plywood plates that pass through, providing good support and adhesion. On the wing side, I left the connectors free for once because the wing root fairing is angled, and the wing root's translation prevents gluing this connector to the wing side.

Back to the fuselage. The battery is a 2S 3000mAh Li-Ion, and the receiver is a Jeti REX 7 Slim. The standard REX6 is too wide.

For the wing ballast (14mm x 14mm), I opted for a brass tube filled with lead. This gives me ten 100g ballasts. Next, I filled the ballast compartments of the wing joiner with 4/6 tungsten slugs and 2/6 brass slugs, all from my FS6 ballast set.

I already explained in a previous post how I made the centering lead. I needed 130g molded + 45g (3 x 15g) removable weights for a center of gravity at 100mm. Unfortunately, the center of gravity shifts quite quickly as soon as the ballast compartment in the wing is full. The forward CG thus shifts by about 6mm, which is significant. I therefore have to gradually remove the 45g of lead from the nose to maintain the recommended center of gravity around the ideal position.

I know the manufacturer is working on a suitable solution that should prevent this problem.

Finally, the glider weighs 2380g empty.

Video of the Odin's maiden flight !

2026-05-04T22:31:00.008+02:00

Glider at 2.37kg, empty, and wind between 1 and 3m/s.

Odin Maiden Flight

2026-05-04T22:30:00.002+02:00

I was planning to launch the Corps slope for the 2026 season, but I later learned that I'd been beaten to it by colleagues last Friday. The forecast was for good weather but little wind, so the slope we chose offered the hope of good thermals and thus salvaged the flying session.

So, Serge and I met up in the early afternoon. On the agenda for me was the maiden flight of the Odin, which I'd finished that morning.

The model weighs 2375 grams empty with a 100mm center of gravity (I'll come back to the assembly in a future post, I know... I'm not doing things in order anymore, everything's falling apart!). Everything went smoothly. The glider handles well in thermals, although that's not its primary purpose. It clearly detects thermal updrafts. The flaps are very sensitive, and you need to trim the nose down because the glider tends to lift.

Of course, with the light winds, I flew empty all afternoon, but I managed to gain some altitude and practice some F3F laps flights along the slope to get a feel for the model and discover that it glides particularly well, even in turns, with firm but not harsh grip. It retains its energy for a long time, allowing you to link base flights without getting tired.

I flew all afternoon, alternating between searching for thermals, a bit of aerobatics, and mostly F3F laps flights. The Odin is a well-designed glider. Now I just need to test it in stronger conditions, on a slope more typical of F3F gliders, and see how it handles with ballast.

I took advantage of Serge's presence to hand him the radio and take the in-flight photos that I'm sharing with you.

Manufacturer website: https://www.rollincomposites.com/

A weekend of wind and stunning scenery!

2026-05-04T19:27:00.005+02:00

Twenty competitors met south of Grenoble in the Alps for a French F3F Cup competition organized by the Brié Alpes Soaring club. The weather allowed us to fly for two days with winds ranging from 8 m/s to 20 m/s, sometimes within the same minute...

We completed nine rounds on Saturday and six more on Sunday, bringing our total to 15 rounds and the second joker, which proved very useful as the slope was extremely variable, sometimes even during the same flight.

The best time was achieved by Matthieu Mervelet in 30.43 seconds on a Shinto glider with a 3.8 kg weight. Pierre Diatta also clocked 30.97 seconds on a Radical Jazz. Many pilots achieved sub-40-second times.

A special mention goes to Thomas Mervelet (only 11 years old!) for his outstanding performance in the competition, achieving a 38-second run followed by a 36-second run. A huge congratulations to him for handling it like a pro, showing no fear of strong winds and mastering the sometimes tricky landings.

Pierre Diatta won the competition, followed by myself and Matthieu in third place.

On Sunday, we decided to shorten the competition in the early afternoon as the sky was becoming threatening with a risk of rain, and the competitors had had their fill of cold and wind. So everyone was happy to pack up and gather for the results announcement, followed by the traditional drink before hitting the road again.

A big thank you to everyone for rotating between the launch sites and for the launchers, and a huge thank you to the rest of the organizing team: Joël Marin, Serge and Marie-Hélène Delarbre.

Full result: https://f3xvault.com/?action=event&function=event_view&event_id=4223

FUKA VTPR by Fred

2026-04-29T07:28:00.005+02:00

Texte et Photo: Eric Collard

Pourquoi un FUKA ?

Après des années d’arrêt de l’aéromodélisme (30 au bas mot), je reprends tranquillement ma progression vers des machines de plus en plus intéressantes.

J’ai commencé par un Switch pour retrouver les bases du vol de pente (je recommande) et mon vieux MiniJ dans les conditions light. J’ai suivi par un STIGRA en EPP qui me sert de testeur de pente et de modèle de brousse pour exploiter les pentes bardées de caillasse de la région marseillaise. Avec ce STIGRA, j’ai découvert le vol type VTPR, ultra-maniable dans un petit espace et proche du pilote. Je cherchais un modèle dans le même gout, mais avec de l’accélération, de la pénétration dans le vent, et de la ressource.

J’ai longtemps hésité entre le KAREI de Jerem’aero, et le FUKA de frédéric Hamon. Les deux présentent l’avantage d’être fabriqués en France et il me parait important de faire travailler les artisans français dès que l’on peut. J’ai choisi le FUKA pour avoir un modèle de plus petite taille, donc plus facile à caler dans la voiture être la planche à voile et le vélo.

C’est un VTPR en construction traditionnelle : fuselage moulé fibre / ailes polystyrène coffrées balsa, conçu autour d’un profil TP66 (aile) et TP29 (Stab), pour une envergure de 1m65.

L’échange avec Fred a été très fluide, et j’ai choisi une formule où il a fait pas mal de boulot, y compris mise en croix, l’entoilage vinyle avec déco personnalisée. Il restait quand même un peu de boulot, alors je vous propose un step by step des opérations à réaliser avant de mettre la bête en l’air.

Contact : https://fred-vtpr-gliders.e-monsite.com

Montage et finitions

Installation des servos d’aile

On commence par le fraisage des emplacements de servos dans les ailes, à la défonceuse, puis le placage des fonds de puits avec un contreplaqué de 0.5mm.

On en profite pour faire passer des câbles grâce aux fils guides laissés en place par Fred lors du placage des ailes.

Pour les servos, j’ai suivi les conseils du constructeur en optant pour les BMS115 BlueBird.

Ils sont vissés dans 2 petits tasseaux collés sur le contreplaqué.

Des palonniers sont découpés dans une plaque de fibre de verre de 1mm (plans fournis par Fred), puis collés à la résine dans les gouvernes. La liaison est basique : corde à piano coudée en Z, soudée sur une chape réglable … tout simplement.

Ils sont soigneusement soudés aux câbles pour éviter les risques de déconnection et autres faux contacts. De la gaine thermo finalise le tout. De toute façon, en cas de nécessité de remplacement, ce ne sont pas 3 soudures qui doivent faire peur.

De l’autre côté, les 2 servos de chaque aile sont connectés à une prise Multiplex femelle. Ma méthode perso : les deux + et les 2 - sont soudés groupés sur deux broches centrales, et les 2 signaux sont soudés sur les pins externes.

On fait la même chose côté fiche mâle avec les prises qui iront sur le récepteur.

Contrairement à mes autres modèles, je n’ai pas collé les prises Multiplex dans les couples d’emplanture d’aile et dans les flancs de fuselage. Le fuselage étant très souple, il aurait fallu beaucoup le renforcer dans cette zone pour qu’une connexion « automatique » puisse fonctionner. De plus, comme on fixera les ailes avec un système élastique (voir plus loin), il y aurait eu trop de risque de déconnexion en vol. On se contenta donc de connecter les prises mâle et femelles mensuellement, et de laisser le tout libre dans le fuselage.

Commande de profondeur

L’étape suivante consiste à monter le palonnier de commande de profondeur avant de coller le couple support de la dérive.

Le palonnier doit tourner librement sur un morceau de tube carbone qui fait office d’axe. La clé (jonc carbone) des 2 stabilisateurs viendra s’insérer dans le petit tube.

J’avais pour projet de laisser ce jonc amovible, mais je n’ai pas réussi à faire tenir le tube de façon suffisamment solide avec un collage interne. Une fois tout fermé par le couple de dérive, on ne pourra plus intervenir sur cet assemblage, donc on a intérêt à ce que ce soit suffisamment fiable. J’ai donc fini par coller le tube et le jonc carbone, tout en laissant bien t’entendu le palonnier libre en rotation sur le tube (solution 1). L’autre solution fiable consisterait à percer le fuselage un peu plus large de façon à laisser le tube le traverser et effectuer un collage externe (solution 2).

Platine radio

L’étape suivante consiste à découper la platine (plan fourni) puis ajuster les perçages pour les servos choisis. Pour ma part, ce sera un KST CM509MG pour la dérive, et un KST X10 pour la profondeur. Le servo de dérive est placé en position centrale, et celui de profondeur sur un côté.

La platine radio est alors collée avec de la résine epoxy chargée de micro-ballon et silice. Elle est volontairement positionnée en biais pour permettre à la commande de profondeur de passer au-dessus des câbles de dérive. Sur la photo ci-dessous, le trait rouge représente la platine, le bleu de commande de dérive, et le vert la commande de profondeur.

Attention : la commande de profondeur doit tout le même passer sous le tube de clé d’aile. Veillez donc à positionner la platine suffisamment bas.

Les servos sont mis en place, puis la commande de profondeur est réalisée avec un tube carbone de 4mm.

Du côté palonnier de profondeur, j’ai collé directement une chape acier. De toute façon, cette partie ne sera plus accessible ensuite. Côté servo, j’ai utilisé une chape alu à rotule, vissée sur un embout de chape fileté, lui-même collé dans le tube carbone. Cela laisse une possibilité de réglage pour que le neutre soit parfait.

Commande de dérive

On commence par découper un palonnier dans la plaque de fibre de verre de 1mm. J’ai choisi de le faire en une pièce pour que les câbles ne tirent pas sur le collage. Il faut ensuite évider la dérive pour passer le palonnier, puis le coller à l’epoxy.

C’est ensuite le moment de coller le couple de dérive (résine + micro-ballon). La dérive est alors montée sur le couple de dérive à l’aide de 3 charnières plastique articulées. Elles sont collées en place avec de la cyano lente pour que l’on ait le temps de tout mettre en place avant séchage.

La commande de dérive est réalisée avec un aller-retour de câbles connectés sur le palonnier en fibre d’un côté (câble serti) , et sur le palonnier de servo de l’autre. Côté servo, l’utilisation d’embout de chape à œil permet de régler le neutre et d’adapter la tension des câbles.

Connexion Ailes / Fuselage

Après collage des 2 tubes de clé d’aile, il reste à assurer le maintien en place des ailes. J’ai choisi une solution basique mais efficace : 2 crochets vissés dans les couples d’emplanture des ailes, un passage oblong dans chaque flanc du fuselage, et un gros élastique qui relie les 2 crochets. Compte tenu de la souplesse des flancs, cela permet de ne faire supporter aucune contrainte par ces derniers.

Installation radio

On touche au but en finalisant l’installation radio avec un récepteur 6 voies, et un interrupteur magnétique. Pour l’accu de réception, j’ai choisi un 1000 mah en 2S plat. Il vient se loger dans le nez juste derrière le lest.

Centrage

Le centrage recommandé à 83mm (ne pas tenir compte du 77mm de la doc, qui était donnée par Predim’RC mais bien trop devant), m’a fait mettre une 60aine de gramme de plomb dans le nez.

Pour confectionner le lest, j’utilise toujours la même technique. Je plante le nez du planeur dans un pot contenant du sable mouillé, afin d’avoir une empreinte, puis je coule du plomb fondu dans cette empreinte. Une fois refroidis, un petit coup de ponçage, pour ajuster la forme et le poids puis on colle le tout dans le nez avec une pointe d’epoxy.

Réglages débattements

Dérive : max avec pas mal d'expo pour avoir un peu de finesse autour du neutre.
Profondeur : +15/-15 ça suffit. Expo 15%
Ailerons +20/-20 mm pas de différentiel. Peu d'expo
Volets couplés aux ailerons tout le temps : +10/-10 pas de différentiel et peu d'expo, idem ailerons.
Snapflap (préconisation de Fred, pas encore testé pour ma part) : Volets couplés à la profondeur. Idéalement une courbe personnalisée qui te permette d'avoir 3 mm de courbure dès que tu touches le manche de profondeur puis plus rien jusqu'à 80% des débattements de ton stick et sur les derniers 20% 8 à 10 mm. En gros :

Profondeur a cabrer au max, les volets se baissent de 8 mm
Profondeur à piquer au max les volets remontent de 8 mm.

Crocodile :

Volets baissés au max (je règle planeur posé au sol, je descends les volets jusqu'à ce qu'ils soient en contact avec le sol et je relève de 5 mm)
Ailerons relevés de 5 mm (juste pour stabiliser l'aile, pas besoin de plus, les volets freinent assez).
Compensation profondeur entre 6 et 7 mm à piquer.

Housses

Pour finaliser ma préparation, j’ai sorti la vielle singer pour faire quelques housses, histoire de protéger les profils et ne pas perdre les différentes clés (2 pour les ailes, 1 pour les stab)

Premier vol

J’ai profité du dégel pour faire un tour à Sederon et découvrir un site de vol particulièrement intéressant.

Conditions : Nord 6-8m/s

Dès le premier lancé, le FUKA est très neutre. Aucune retouche de trim sur les ailerons, et juste un cran sur la profondeur.

Avec des conditions plutôt porteuses, le FUKA monte vite et accélère fort ! Par rapport au STIGRA, ça fait presque peur (je n’ai pas l’habitude), mais les trajectoires ressemblent enfin à celles d’un vrai planeur.

Grace à des gouvernes surdimensionnées, le taux de roulis est impressionnant, mais tout est très précis. Idem à la profondeur et à la direction : le FUKA est un planeur très vif et dynamique, mais à la fois très facile à piloter car prévisible et réactif.

J’ai peaufiné le réglage de la compensation du crocodile : Il m’a fallu en mettre bien plus que prévu, car avec des flaps très baissés et des ailerons très peu relevés, cela nécessitait une compensation importante à piquer.

Pour ce premier vol, je me suis contenté de jouer avec les trajectoires, et de profiter des magnifiques ressources. Pour la voltige de base, on jouera plus tard.

Reste à tester le poser sur un spot que je ne connais pas du tout, et avec un planeur bien plus rapide que ceux dont j’ai l’habitude. Fort heureusement, le sommet très arrondi de Sederon permet une approche en faisant le tour de la pente pour se poser face au vent sans trop de turbulences. Les flaps sont très efficaces, et permettent une approche et un atterrissage en douceur dans l’herbe bien douillette.

Je suis super satisfait de ce premier contact, et j’attends avec impatience d’autres conditions « sympa » pour continuer cette belle découverte. A suivre donc !!!

Silicone Mold Technique

2026-04-28T22:54:00.001+02:00

Successful first attempt at molding a centering lead for the Odin using the silicone mold technique.

First step: create a master of the inner nose using 3D printing, either by iteration if you don't have access to the CAD file, or using the file provided by the manufacturer.

Prepare the container for the mold; in my case, a cardboard cup. Position the master on top of the cup; I used a flat stick. Next, prepare the silicone mixture (heat-resistant type) in a 1:1 ratio, mix it well, and then pour it around the master. Add some weight on top of the master, as it tends to float otherwise.

Wait overnight or longer, and then you can proceed to mold the lead.

The result is convincing.

ODIN Kit Overview

2026-04-21T07:24:00.004+02:00

A quick debrief about the kit of the ODIN I received 1 week ago. This is 100% designed and made in France by Rollin Composites who is also manufacturing the Graphen, a sport flying electro glider.

Here, as a reminder, are the characteristics of this competition glider.

Specifications:

Wingspan: 300 cm
Length: 142 cm
Wing profile: JLF (proprietary)
FAI area: 61.14 dm²
Empty weight: 2.35 kg
Max FAI weight: 4.585 kg
Ballast: 1,840 g brass
Nose length: 346 mm
Root chord: 240 mm

Options: ballast kit, wing and stabilizer covers

Manufacturer's website: https://www.rollincomposites.com/

The glider arrived well-packaged and securely fastened in its cardboard box. I opted for the wing and stabilizer covers, made by Pull-Over. However, I didn't choose the bass ballast option, but I'll come back to that later.

Unboxing the kit, I must say I'm very pleasantly surprised by the quality of the molding and finish of the glider, which compares favorably with the top-of-the-line gliders on the market.

The wings are very nice, shiny, with a beautiful intensity of fluorescent paint. The stabilizers are of the same high quality.

My layup is 160g/dm² bi-axial carbon fiber. The wings feel very rigid, both to the touch and under flex. Inside each wing, there's a 25cm long, 14x14mm ballast compartment (Baudis-style) centered on the CG, plus compartments in the wing joiner for 10x10mm ballast. The downside is that if you don't already have tungsten in stock, it's going to get complicated because prices have skyrocketed to 250 Euros per kilo. With brass, you'll quickly need to use the ballast in the joiner, which will inevitably move the center of gravity forward, and by a significant amount. There's also the alternative of lead ballast, which I'm working on, so I'll talk about that later.

The fuselage is superb with the exposed carbon fiber, and very rigid. The rectangular stabilizer joiners inspire confidence. The front of the fuselage isn't cut out, which allows you to choose how you want to install it.

The stabilizers, also very beautiful, fit perfectly on the fuselage.

An accessory pouch is included with the kit. It contains twisted cable, green MPX connectors with small, very practical mounting plates, and servo covers.

In short, a beautiful piece of work. Well done, Loup Rollin, for the work done. I can't wait to fly it. But first, I have to assemble it.

Oh, before I go, here's the weight of the different components.

Left and right tails: 42 gr each
Joiner 96 gr
Fuselage + nose cone 269 gr
Right wing: 682 gr
Left wing: 695 gr

The target is to have an empty flying weight around 2.4 kg

Stay tuned for the assembly !

First flying session in the mountains of 2026

2026-04-20T07:37:00.004+02:00

First flying session in the mountains of the 2026 season with Serge, Joël, and Benoit. Beautiful weather with a wind around 10 m/s and excellent lift. I had a blast with Jerem Aero's Tsubasa, really comfortable in the wind and yet only 360g empty, incredible! I also got to do the first flight of my Wasabi 2, the strong version, weighing 4466g empty. I had a great time there too. Here are some photos of the models present: Q2, Wasabi 1, Wasabi 2, Freya electro, Karei, Tsubasa.

(Photo credit: Joël Marin & Pierre Rondel)

Flying the Tsubasa

2026-03-30T07:27:00.005+02:00

The real fun begins with this third flying session: Gray and cold weather, but a steady wind between 6 and 9 m/s on the local slope and no one in sight, I have the slope all to myself.

For the flight, I confidently set the center of gravity; all that remains is to fine-tune the aileron differential. After a few runs up and down the slope and a few clicks on the rudder trim to adjust the aileron differential, I tackle the aerobatics. And what a pleasant surprise! The Tsubasa performs aerobatics quite well. The reversal is fairly smooth, even with a little aileron input. The energy recovery allows for impressive vertical climbs, despite its weight of only 365g. Looping is easy, requiring only a slight increase in airspeed, and remains well-controlled throughout. The roll is a breeze, and even the four-way roll is executed without a hitch. Inverted flight is perfectly stable. The fast passes followed by a few basic F3F maneuvers are also quite enjoyable.

It remains to be seen how it performs in Dynamic Soaring on the darker side of the slope. And there too, I'm blown away. At 1m and 365g, the Tsubasa really performs well; it picks up speed easily, remains controllable even in turbulence, and is never dangerous. I really need to add a ballast tube because I'm sure it will be even better.

In short, this Tsubasa, besides being incredibly cute, is packed with qualities.

https://www.jeremaero.com/product-page/tsubasa

Electro Quantum 3DP

2026-03-24T21:51:00.004+01:00

Upcoming project: an electro Quantum 3DP. It's actually a Q2 F3G fuselage, but it fits quite well with Q3 wings. Only the position of the green MPX connectors needs adjusting.

Back when I was building the Q2, I had the first fuselage off the mold. This time, I received a production version, complete with the servo tray designed for flat-mounted MKS HV75 K-R servos, carbon fiber linkage, and accessories for the green connectors and receiver extensions.

The fuselage is designed for a 28mm diameter motor and can be fitted with a 3S, 4S, or even higher battery, depending on preference.

In my case, this fuselage is for use with the wings of my Q3 Strong (2300g empty), so I hope the electric version won't exceed 2.4 or 2.5kg ready to fly.

https://www.sandamodels.com/

Revoc Viola back bag

2026-03-22T09:37:00.002+01:00

I would like to present the Revoc Viola backpack that we received for the raffle organized by the French F3F team. It will be up for grabs in the next draw, with details to be announced soon.

Over the years, Revoc has become a leading specialist in protective covers, both for gliders and airplanes, offering an impressive catalog of products. They also provide very practical universal transport bags, especially useful for slope flying.

I have previously presented the large “Double Glider Bag” in these pages. Today, I’m introducing the Viola, a lighter bag with slightly less capacity but just as practical.

The Viola bag can easily hold two F3F models, or alternatively a 4-meter glider. The expandable lower pocket allows you to fit a wide fuselage, which is very convenient.

A few details about the construction: the Viola bag fabric is made from three layers:

An outer layer of durable polyester fabric designed to protect your glider wings from external factors such as water or sunlight.
A middle layer consisting of 3 mm of very lightweight polyester padding to absorb impacts and protect the glider components. This soft and lightweight padding also makes the VIOLA backpack easy to carry and even fold for storage.
An inner layer made of smooth black polyester that is soft and non-abrasive, preventing scratches or marks on wing surfaces. Nowadays we often use wing covers anyway, but it’s still good to know.
The bag comes with a semi-rigid divider to be placed between the pairs of wings.

Four colors are available to suit different preferences. However, I personally recommend choosing lighter colors, as dark-colored bags heat up quickly when left in direct sunlight—so black should be avoided.

In addition to color choices, like all Revoc bags and covers, it can be customized with text or a logo. We actually did this for this one, which is branded “Team F3F France”!

There are also some nice practical details, such as the side handle that allows you to hold the bag vertically when sliding it into a car trunk, or the loop strap that lets you hang it on a workshop wall. The bag can also be folded in half and stored easily on a shelf, taking up much less space.

At the top, there is an additional pocket designed to carry detachable horizontal stabilizers or wing joiners. This pocket measures 57 cm in height and 23 cm in width.

A quick note on build quality: once again, it is truly premium, both in terms of materials, stitching, and finishing. This is a bag that will last you for years. Personally, I own several Revoc covers (Nan Compass, ASW17 FW), and I can confirm their excellent build quality and durability.

REVOC VIOLA Bag Specifications:

Height: 165 cm
Width: 29 cm
Depth: 12 cm

https://shop.revoc.eu/glider-backpack-viola

Price: €140

Tsubasa video

2026-03-19T08:04:00.004+01:00

A short video of the first flight of the Tsubasa.

Tsubasa maiden flight

2026-03-18T07:36:00.006+01:00

In the air !!!

I managed to make the Tsubasa's maiden flight last Sunday before the wind picked up and the competition started. The launch site wasn't ideal for a first flight, as a cliff doesn't forgive the slightest mistake, and landing at the bottom is impossible. Furthermore, if the wind is too strong, landing behind the ridge is impossible; you have to walk 500 meters into the valley behind the slope, which is inconceivable with a small 1-meter wing.

I judged the wind wasn't too strong for a first flight and asked Pascal to launch the wing for me. The wind was between 8 and 9 m/s. The launch was a bit bumpy, but the Tsubasa quickly stabilized and gained airspeed.

My first impression was that the elevator was extremely responsive, and since I had to use a few clicks of trim to pitch down, I concluded that the wing's center of gravity was too far back. Jeremy had advised me to start with a 46mm center of gravity. I promise I'll do that for the next flight!

Despite the sensitivity of the elevator, I managed a few runs along the slope. The flight speed is fast, especially for a wing under 400g! The Tsubasa glides extremely well, penetrates the winf with ease and has excellent control. The high rudder gives the wing very good stability, and its trajectory is impeccable.
For the roll, not axed, I'll need to review my settings once I find the center of gravity.

In short, the first flight only lasted 3 or 4 minutes, but the Tsubasa already showed impressive acceleration and glide capabilities. I can't wait to fly it again and fine-tune it properly, then try the DS light.

I also plan to add a ballast tube.

To be continued!

Tsubasa Assembly

2026-03-16T22:08:00.002+01:00

Some information about the Tsubasa assembly. For the servos, I had two MKS HV 6100s mounted vertically in stock, but fortunately, Servorahmen makes a servo frame for this.

The servo location is the right size, so it fits perfectly, but there isn't much room around it.

I initially wanted to use a standard servo horn, but the servo configuration with the motor housing protruding on top doesn't allow it. Then I had the option of using ServoRahmen horns with a standard linkage, but then the aluminum tube is 4mm in diameter, not really suitable for the size of the model.

I finally found some RTGModel-type servo horns in anodized aluminum, designed for use with a 2mm threaded rod. So I went with those, using aluminum clevises from Tomas Liu Studio on the control surface.

The most critical step, and I mean it, is to precisely determine where to drill through the upper wing surface (extrados) to route the control link to the control horn of the rudder in order to minimize the gap. If you mess this up, like I did, you can always 3D print a part to make a nice cover. It looks very professional, but the truth is it's more of a cover-up, at least in my case, I prefer to be honest with you!

I didn't use extension wires because the servo wires were long enough to reach the canopy and be connected to the receiver, which is then pushed into the fuselage.

For the fin, I opted for a removable one, making a small alignment pin to ensure the rudder was perfectly vertical rather than using a pin. It's then simply taped in place.

Back to the front: I needed about 20 grams of lead for the center of gravity. I molded it to the shape of the nose. The battery is a 2S 450mAh LiPo, more than enough for two servos.

The antennas are taped at a 90° angle with Blenderm adhesive to the bottom of the fuselage.

Since the servo heads protrude slightly on the underside of the wing, I also designed and 3D-printed custom servo covers.

A quick weigh-in reveals a final weight of 365.5 grams ready to fly, with a recommended center of gravity of 48mm.

Mistral Soaring N°5

2026-03-16T07:36:00.003+01:00

Yesterday was the final round of the Mistral Soaring Winter Cup competition series. The weather was quite favorable, with winds around 11 m/s in the late morning, dropping to around 8 m/s by mid-afternoon. We completed 14 rounds with 8 pilots, then 10 after Antoine and Guillaume joined us. Pascal set the fastest time of the competition with a 36-second lap in a Cosmos. I won this final competition, thus winning the series. Philippe Lanes finished second, and Pascal Vaissier completed the podium. Personally, I flew Wasabi 2 and Quantum 3, Philippe flew FS7 and Orden+, and Pascal flew Cosmos. A big thank you to Joël for organizing these competitions, which remain a must-attend event every winter. Now, on to the 2026 F3F season!

Full results:

https://f3xvault.com/?action=event&function=event_view&event_id=4096

Tsubasa Kit Overview

2026-03-07T22:58:00.000+01:00

I received the Tsubasa kit, created and manufactured by Jerem Aero, on Friday. It’s a small flying wing with an awesome look. It arrived in a custom-made box built from thick honeycomb-style cardboard.

The kit contains a single-piece wing, a small exposed carbon canopy, an exposed carbon vertical fin that plugs into the sleeve at the rear of the fuselage, two 3D-printed carbon aileron horns, and two stickers to close the servo hatches.

The molding quality is excellent and the paintwork is superb, along with a really striking color scheme.

My version is the Strong version. In fact, it’s the very first one of this version that Jérémy has produced. He was expecting an empty weight of around 290 g, but the wing came out at only 256 g, which is just 10 g more than the standard version. This will make this Tsubasa Strong even more versatile.

Let’s take a closer look at the construction details. The servo bays are machined, and the upper wing skin has received an additional layer of carbon.

The spar has an opening to allow the servo wires to pass through. There are false ribs on each side of the servo bay to reinforce the wing against torsion. The servo bays don’t have a lip yet, but this will be added on future kits.

The ailerons are hinged on the underside, in an F3F style, and there is no sealing lip. A bit of tape will do the job.

The vertical fin slides onto the fuselage. I’m still hesitating about how to secure it. A pin could do the job, but I’m thinking more about using a small alignment key for positioning, and then simply securing it with tape.

For the servos, I’m going with MKS HV6100 servos with Servorahmen frames. However, I’ll use standard servo arms with aluminum clevises from Tomas Liu Studio, along with a 2.5 mm diameter carbon rod.

Later on, I’m thinking about installing a small ballast tube.

Alright, enough talking—time to start the build, which shouldn’t take long. Stay tuned!

Manufacturer website: https://www.jeremaero.com/product-page/tsubasa