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Showing posts from August, 2012

Ballasting a F3X sailplane

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It is always a problem to know exactly how to ballast a F3X plane given that they are several ballast compartiments with different size/volume, and none of them is exactly at the center of Gravity. I created the following spreasheet to help you how to determine the ballast, and also calculate the CoG variation.

How to use this spreadsheet?

Enter in the yellow cells:
The position of the CoGThe position of the different ballast compartiment (measured at the center of the compartiment)The weight of the ballast slugs for each compartimentThe empty weight of the plane As ouput, it will give you:
The total ballast weightThe flying weightThe wing loadingIt will highlight in red when exceeding the FAI wing loading of 75gr/dm2More importantly, it gives the variation of the CoG.
Feel free to report mistakes, bugs if you find some. Thank you.

- Download the spreadsheet -

Schwing 88 kit overview

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The Schwing 88 is the first allround slope model born from the partnership between James Hammond (the father of the Strega, Typhoon, Vector, Minivec, and some others ...) and Tony Fu from SlopeRacer.co.uk.

The Schwing 88 is a very nice looking 2.23m wingspan slope plane which includes improvement from previous JH designs, based on feedbacks and learning experience. It features new combination of airfoils, semi eliptical lift distribution, large control surfaces. The fuselage is slim and with a canopy, but still host a massive ballast tube and the servo tray for 2 servos, the receiver and the battery.

The plane is distributed worldwide by SlopeRacer.co.uk or by its distributors in some countries (i.e SoaringUSA). I received one exemplar of the first production batch.

So, what do you get ?

The wings are fiberglass. The finish is clean and the level of completion is high, as expoxy wipers are done, brass control horns are installed, and a carbon reenforcement is in place in the servo ba…

Practice session at Le Col du Glandon

This place is where french F3F was born in 1994. With the coming yearly french league context next week, I drove there to meet with 2 F3F mates and enjoy the north slope. This is the first time this year that I go there, but I should really go more often as the north slope is really appropriated for F3F with its sharp edge. But the main characteristic of this slope is the fact that the breeze is very laminar and consistent, with no or very few thermal influence. Even if the time achieved are not impressive, the flying experience is absolutely excellent, and you can do 200 laps with the same regularity, you can work on the trajectory, the turns, the ballasts, etc ... Wind was blowing around 6 to 7m/s. I started the afternoon empty to finish with 390g of ballast. 
It has been also the opportunity to try my brand new and shiny Canon EOS 650D, a important but necessary investment to continue to propose you premium photography on Planet-Soaring.
Here are the very first shots taken yesterd…

Font d'Urle video clip

I just finished the video clip about Font D'urle F3F contest. Hope you will like it. I has been film with the GoPro on a 3m boom and my Lumix FZ100. No animals were harmed during the filming, but some sailplanes did (at the landing) ! Enjoy !

JR Propo XG8 / XG11 field charging solution

The XG8 and XG 11, powered by a 2S 1400 mAh LiFe battery, have the particularity to integrate the battery charger into the transmitter case. They need a 220VAC / 9VDC adapter, provided with the radio. This solution works great at home but the downside is when you want to recharge your transmitter on the field/slope, and that you don't have 220V source available.

I found a smart solution to recharge my transmitters on the field. I bought a CCBEC from castle creation, which is programmable using the USB link to purchase separately, and which is the only UBEC to be able to go up to 9V, at the opposite of all other BEC which deliver 5 or 6V, not more.

I prepared some cable to use with the CC-BEC, on one side to connect to the transmitter plug, on the other side to connect to a 3S Lipo battery, or to connect to a 12V power source. I will also prepare soon a cigar lighter plug.

This charging solution is very convenient, in addition to be an excellent backup solution. It's light, ca…

Video: slope soaring patrol flight

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The second video from Jean-Marc Zuliani has been filmed on the slope of L'Alpe D'huez. this is an action video with onboard camera and unfortunately a mid air at the end. Story doesn't tell about the damages :( !

Video: A sailplane trek to the "Plateau d'Emparis"

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Jean-Marc Zuliani released 2 new videos recently. This first one has been filmed on the "plateau d'Emparis", a wild and protected place in the heart of the Alps, between L'Alpe D'huez and the "Ecrins' National Park", offering one of the most beautiful landscape of the area. Nice video and editing !

Font D'urle 2012

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This competition is a special event in the french F3F calendar because the organisers have an authorization to fly there and because this is forbidden the rest of the year, being in a very restricted/protected zone. This difficult access make it a sort of pilgrimage for all the french F3F pilots, but also for our friend from Switzerland like Reto and Christian. This year has been an excellent year, in term of participation with almost 30 pilots, but also because of the weather and 2 days of south wind.

On saturday, the wind was not very strong but in round one, but Sebastien Lanes did a 34s that remained the fatest time of the day. We ended with 5 rounds in the pocket, and also with some planes damaged during landing as some pilots experimented time to time rotors during the approach. At the end of the day, Alain Galinet from Briancon was leading, followed by Sebastien Lanes and Matthieu Mervelet in 3rd.

On sunday, we started earlier as the wind was already blowing. Conditions grew u…

Alliaj HM Slim

Aeromod release a new fuselage for the famous Alliaj HM. The new fuselage follow the current F3X trend, so is slim, with the servo tray inverted, with a big ballast tube in the fuselage. This week-end, Jean Luc Foucher used the new Alliaj HM during the competition of Font D'urle. A good opporunity to have a look to it and take some pictures and video. The new Slim fuselage, event it is difficult to say that it improves perfomances, clearly gives a totally new look and elegance in flight as ou can judge on the video below.


Hints and Tips: using a heater cable for fuselage repair

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During the FAI contest of Briançon, I learned a great way to repair quickly and solidely a fuselage boom. The idea consists in using a ground heater cable that guarantees a regular and even heating.


This heating cable is usually used in aquariums, as well as in terrariums. I bought mine in a Botanic shop. 3 models exists: 25, 50 and 100W. For our purpose, the 25W is the one to choose, as it is already 4.30 m long.

One you have done the repair with carbon/glass cloth or tape, you first surround with some large tape or thin plastic sheet, then you roll up the heater cable around the boom and plug it to the 220v. According to the people using it, it provides a temperature around 30 to 40°.

You can also use a sheet of aluminium around the boom before to roll up the heater cable. This will help to propagate the heat all around.

After the night, the fuselage is ready for sanding and painting (if you have time) or flying if you are on a hurry :)

Technical data: Hydor Hydrokable Ground Heater…

Col de Menée

This afternoon, I went to a super F3F spot that has been discovered 2 years ago and that we used during one day of contest of the french league. The only problem of this slope is that it is difficult to reach: 40 minutes of walk, and about 300 meters of altitude to climb, so you need to not take too much planes or equipement to stay light. I took only one Pike, my compact camera, the Go Pro, but also the 2 kg of ballast ...
The slope is very deep, and "capture" the wind very well. Because it is facing north, it is not too much influenced by thermals. Time to time you fly a bit faster, but the difference is not huge.

I was alone on the slope all the afternoon, so flew 2 hours non stop with 700g of ballast. The lift has been consistent during all the time, really a super spot !

Here is a short video I did.


T9 Hobby Sport Magnetic switch

Magnetic switches become very popular in the F3X world because they are very convenient to use in slim fuselages and because they are finally safe as they are passing if faulty during operation.
After testing 3 other magnetic switches, I received this new one from T9 Hobby Sport for review. It is now installed in my Willow F3F and worked flawlessly until its installation.

This T9 hobby sport Hall effect magnetic switch is a nice piece of hardware, with double side board and lots of surface mounted components. It differs from the competiton by proposing 2 things:

1/ A battery charge lead: This is very convenient because now you dont need to unplug the switch when charging. You can really locate the switch in a unreachable place. The charge lead is directly connected to the battery wire so in theory, there is no limitation in term of current or delta peak détection.

2/ A temporisation when switching off: To switch on, just present the magnet over the circuit and the effect is immediate…

New pictures of the French Alpine Cup (Briançon)

Joël Marin, one of the 2 CDs at Briançon for the French Alpine Cup took some pictures during the contest. Here is the photo album. The idea of Joël was to have at least a picture of each competitor. Hope he doesn't forget somebody :)