Diana 2 Flyday

Dani Aeberli from Chocofly.com organised the first Diana Flyday on 16 August 2020, in Eglisau, Switzerland. He brought together 27 Dianas, with pilots coming from as far as Geneva, including three scratch-built Diana 1 (4.28m), a whole bunch of Diana 2 (4.28m, both scratch-built and the Chocofly version), as well as the 5m version of the Diana 2 (scratch-built, and Baudis, and a combination of both), and the Chocofly 6m and 7.5m versions. Our building team was represented by Georg Staub (who came with 8 Dianas!), Andi Schwerzmann (4 Dianas) and myself (also 4 Dianas – lined up in the first two pictures below). Our team supplied all the scratch-built planes (the amazing 4.28m Chocofly Diana2 is the commercial version of the one built by members of our team). Georg and I flew our already 14 year old Diana 1, still a fantastic glider, and we also enjoyed some amazing flying of Dani and his 7.5m Diana2. A you’ll have concluded already by my ample use of superlatives: an awesome day, and a big thank you to Dani for organising it. See below for a few pictures. More pictures and videos can be found on the social media channels of chocofly.com.


Diana2 Flyday!

Save the DATE!

Diana 2 Fly-Day…… Sunday 16.August 2020 at
Modellfluggruppe Zürich, Eglisau (https://mgzh.ch/unser-flugplatz/).
Bring your personal Diana 1 or Diana 2 and Fly with us!
Lets see how many we can get together…..World record??

Saturday 15th will be also first time DONs Grill & FLY

Please sign in on the Doodle Link before the end of July 2020…to make sure you can be part of it!

Looking forward to see you all there
ChocoFly Team


Maiden flight of the Chocofly Diana2 – Glider version

When there is a stable high pressure area north of us, over Germany or eastern Europe, we usually have a stiff northern breeze, called “Bise”. Most of my favourite slope soaring spots are on north-facing slopes, i.e. time to head out. Unfortunately, being a northern wind, it’s also a freezing cold wind, which means that this early in the year you can add a significant wind-chill factor to temperatures already barely above zero degrees Celsius. In cycling we always say that there is no such thing as bad weather, just bad gear. Following that wisdom I went out on Tuesday to my favourite slope, with chilly but perfect wind conditions. The slope is perfect Diana territory – I usually fly one of my Dianas (Diana 1 or 2) there. With the whole Covid-19 lock-down I drove up alone and had to hand launch the plane myself. This is one of the reasons that last year I ordered an extra fuselage for my Chocofly Diana2 (1;3.5), and built it as a light glider without the usual FES (5.5 kilos). Normally I maiden my planes on a nearby airfield, using a towplane. But extraordinary circumstances require extraordinary actions. And as I know the Diana2 pretty well by now, having clocked many hours on the various version I have, I hand-launched it myself on the slope for the maiden flight. It flew off without any bother and I spent a wonderful 75 minutes in the freezing cold. The nice thing about the Diana2 is that it’s such an amazingly versatile plane. It thermals amazingly well and loves low as well as high speeds. At 5.5 kilos it’s not as fast my heaviest version, which weighs almost a kilo more, but still very fast and a lot of fun to fly. I’ll be taking this one to the slope more regularly.

On the slope I met up with my mate Richie, who was also flying his Diana2 (the Chocofly Diana2 is the commercial version of the design from Richie and Georg). Hence the photo below of the two sisters together. His Diana2 is even lighter, well below 5 kg, and on the slower side, but goes up like a little balloon in the least bit of upwind.

In-between: another Diana2….

With the JS3 maiden flight still to go, my favourite plane by far remains the Diana2. So far I had three versions: my 1:3.5, 4.28m and 5.65kg scratch-built (my favourite!), the Chocofly derivative of our scratch-built (identical size and profile), with 6.3kg (Alpine version) as well as the Baudis/Chocofly 1:3, 5m version (8.2kgs). The great thing about the Diana2 is that it’s such a versatile plane and can be flow in weak thermals and in extreme slope conditions. It performs very well at low weight (a real “balloon”) but also carries ballast and higher weight extremely well, when it becomes a real racer. I’ve been wanting to built a “light” version for a while. Chocofly was able to supply me with an extra fuselage, which I’ve now built as a light glider. It’s ready to maiden, and I hope to do a first aerotow soon, and use it on the slope afterwards.

Baudis Diana 2 (1:3 – 5m)

As a huge Diana2 fan I couldn’t resist ordering a Baudis 1:3 version last summer. The plane was delivered a few weeks ago. Now that the AvantiHawk is airborne getting the Diana2 ready will be my priority for the next few weeks. Fortunately the amount of work that still needs to be done on this is limited – fitting canopy, motor and retractable gear, as well as the rudder servo. The wings and elevator servos are already installed. Initially I intended to build my own fuselage with this plane (we have moulds for our own 1:3 Diana2), following the example of Georg, one of the other members of our “building team”. Seeing how much work was needed to adjust the fuselage to the wings, and being unable to resist the urge to fly this plane during this season rather than only next year, I decided to go with the original Baudis fuselage instead (which Dani from Chocofly was able to deliver on very short notice, thanks Dani!). Unfortunately the Baudis fuselage is quite “anorexic”, compared to our own fuselage, so I may still want to do a self-built fuselage sometime in the future.

In the meanwhile…Diana 1 and 2

I can’t resist the temptation to squeeze in a few non-JS3 pictures. Last week Friday I maidened my 1:3.5 Chocofly Diana2. This plane is the exact copy of the Diana 2 that was designed by members of our JS3 team now almost ten years ago (using the same wing design, profile and fuselage), and of which I already built one from scratch last year and had a lot of fun flying it since. My new Diana2 is the Chocofly pre-production heavy slope version. With 6.3kgs it is heavier than my scratch-built Diana 2 (5.8kg), but also a very robust slope racer – looking forward to putting this one through its paces on one of our nearby slopes soon.

We also had a family excursion of our full set of scratch built Dianas, me flying my refurbished 14-year old Diana1 (SZD 56.1), built by Richie, Richie flying his 1:3 Diana 2, and Georg his 1:3.5 Diana 2. Bliss. Oh, and yes, we love our Dianas. The Diana2 is still the best plane I’ve ever piloted, but maybe our JS3 will change that?

IDS system for the wing control surfaces

I wrote earlier about our servos, but not in detail: we will be using KST X08plus for the ailerons on the outer wing of the 5.14/18m version, ChocoMotion 8/5.0 for the ailerons, and Chocomotion 10/9.2 (in size identical to the KST DS225MG, but more powerful) for the rest of the control surfaces (6 Servos in the 4.28/15m wing and 8 Servos in the 5.14/18m wing).

Today I received a large package from Servorahmen.de in the mail. Servorahmen.de provides servo frames with Integrated Drive System (IDS) for all the servo types we will be using. We have used their IDS system on most of our gliders in the past few years, including last year’s scratch-built Diana2 (1:3.5). The frames fit well, are robust and good value. The IDS system can be fully integrated into the wing, so no ugly protruding levers or large holes in the wing surfaces. Most importantly, they provide a wing surface control that is extremely direct and completely without play. Fitting the IDS frames requires more effort than standard systems, but the result is definitely worth it. Below are two pictures of the system built into my 1:3.5 (4.28m) Chocofly Diana2 that I hope to maiden soon. The Chocofly Diana2 is identical to my scratch-built Diana2 (which was designed by members in our team), except that the wings were built in a mould.