Showing posts from November, 2010

Home made ball link pliers

After buy few different ball link pliers that was not working at all on my gliders (for tailplanes), I decided to build my own. I use it to plug or remove the ball link on the tailplane. It works like a charm.

To build your own ball link pliers, you just need a low price flat nose pliers, and with a mini drill, you grid a slot in one of the nose:

Then shorten the other nose by 5 mm.

2.4 Ghz: The judgment day is approaching …

When 2.4 Ghz appeared few year ago, lots of people were wishing a convergence of the systems in order to be able to mix brands together like we can still do with PPM radio.

But this dream is, from my point of view, flying away with what we see currently on the market, and worse than that, large manufacturers are suppressing PPM transmitter from their catalogue to offer only 2.4 native transmitters.

Today, it is impossible to find a Futaba T10FG. Graupner is selling out the MX12s and MX16s. When you open big shop catalogue or website, you don’t see anymore PPM radio.

Another example with Multiplex who is protecting their transmitter by supressing the PPM signal on the Royal Pro. When you send a Royal Evo for maintenance, it comes back with the firmware of the Royal Pro !! too bad ...

This prevents the end customer to buy a PPM transmitter, then install any 2.4 HF module of his choice. All alternative brands, with affordable prices, are in danger in a near future. I think this explains…

Servormance max torque versus blocking torque

Following my post about the test results of the DS6125, I received several mails asking me about the difference between the max torque measured by Servormances and the max torque indicated by MKS. More generally the question is the same for all other servos tested with Servormances. So I think it was necessary to come back on that topic and give more information in order to avoid any confusion.

As we say in french, we can not compare apples with oranges, and this is a little bit the case here, so let me develop further:

On the manufacturer specifications the max torque mentionned is the blocking torque, that is to say the torque at which the servos cannot rotate anymore. The servormances team took another approach. Servormances max torque is very restrictive as the value published respects the following criteria:

Precision is within a range up to 1.5°Speed is better that 0.8s for 60° of travelPower Consummation is under 80% of the max consummation measured

Taking the DS6125 under 6v as…

Ambrosia F3X ready for maiden

I finished the Ambrosia this week-end. I found in a DIY shop a square steel tube with the right dimension, 14x14mm, and some wood for the spacers.

I made slugs length in order to have 2 slugs per compartiment, that is to say 4 slugs per wing. What is interesting is that compartiments are located on each side of the joiner which garanties that the CG will not move too much when ballasting.

Each slug is about 160 g.

And the total ballast weight is about 1300g, which is perfect

I also did the CG balance of the plane and moulded the lead for the nose. I needed around 150g of lead which is not too much considering the fin and tailplane which is usually heavier than a V-tail.

The total weight is 2250g. The Ambrosia F3X is ready for maiden :) !!!

First flight next week-end if the weather is cooperative. We had snow falls the last days ...

Stay tuned !

Ambrosia F3X assembly "Part 3"

Assembly continued with the wing servos and pushrods installation. The Ambrosia F3X comes with the brass ring-screws. You'll need 8 clevises (M2), some threaded rod and also aluminium tube with an internal diameter of 3 mm. First of all, I grinded 4 clevises (that will be on servos side) in order to use the servos arm hole the closest to the axis.

Then, the servos being in place in the wings, I cutted the threaded rod at the right length, glue with some rapid epoxy the clevis on the ailerons/flaps side. Once dry,  I glued the clevis at the other end, and inserted a 3mm aluminium tube to make the control rod more robust and stiff. The reason I fix the clevises with rapid epoxy glue to to suppress any possible slope on the command. You will also notice that the ring screws are not glued in place. It will be done at the very end because once in place, the clevises cannot be removed anymore.

Then, I drilled the wing plug housing at the root of the wing. The housing is at the perfect di…

Some aerial pictures

The weather was beautiful today, so I decided, during the lunchbreak, to do some aerial pictures of the mountains around.

Ambrosia F3X assembly "part 2"

I continued the assembly with the servos installation, in the fuselage and in the wings. In the fuselage, the DS6125-H are simply screwed with the woodscrews provided.

Pushrods are made from metal tube with a external diameter of 2mm. First, I cut them at the right length before to fix a M2 treaded coupler at the end. I used MPJet couplers made from brass because they are execellent quality.

Usually, I glued, then pinched the M2 treaded coupler on the pushrod. Prior to that, I inserted 5cm of 1 mm pianowire in the tube in order to not crush the tube when pinching the coupler.

I started also to have a look on the battery to use. This is straigth forward: 4 eneloop cells mounted in 2+2 format will take place easily in the nose.

They enter without any problem by the canopy, once servos are in place. This is a good point because the canopy is not that big.

On the wing side, I prepared the servo holes to receive the wood frames. Once positioned, I glued the frame with rapid expoxy (10 mn R…

Aerial Pictures: Grenoble and Belledonne

Taken last saturday using an EasyGlider equiped with a Sony cybershot DSC-W350. It was already late in the afternoon, and the shadow created by the sunset and the mountain was not ideal. The picture is above the south of the grenoble valley, where are located some chemical plants.

If you look carefully on this second picture, you will see a small part of the Mont-Blanc, behind the mountain range the highest summit in Europe with 4807m

The mountain range is Belledone: Belledonne (French: La chaine de Belledonne) is a mountain range (French: massif) in the Dauphiné Alps (part of the French Alps) in southeast France. The Belledonne range is approximately 60 km (37 mi) long by between 10 km (6.2 mi) wide. There is no road that cuts across Belldonne (source Wikipedia).

Sad news: Hans Graupner passed away

One of the legend of the aeromodelling died during the afternoon of the 11th of november, only 2 weeks after his retirement has been announced officially during a press conference in Friedrichshafen. Hans was 81 years old.

This sad news has been announced here:

This is a big lost for our hobby.

Raviole Soaring episode #1

Raviole Soaring is unformal regional winter league competition in order to be busy and have some practice during the winter. We selected small slopes, not high in order to not have snow, or at least a low probability. The name "Raviole Soaring" has been chosen because of th food speciality of the area: This regional speciality of the Dauphiné perfectly suits our ways of modern consumption: easy to prepare and quick to cook - only 1 minute!

More information can be found here

Let's come back to the contest. 12 pilots from the area met around 10 am this morning and completed 4 round before the lunch in a strong wind (about 40 to 50 km) with some dust reaching 60 km/h. The slope is a grass field, with slow angle slope.

Then we had a lunch break of 1 hour to cook and eat some ravioles and other great specialities :) ! Then we started again for 4 additional rounds until 4 pm.

Yves Tirand won the competition with his Vampire. I got the fastest time with 41,72s. I thing this sl…

Ambrosia F3X assembly started

I started the assembly of the Ambrosia F3X. First I prepared the wing servos wire and te equivalent in the fuselage. I use DIY plugs because you can make the exact length you need, and also because it is much cheaper. Ambrosia F3X has MPX green plugs housing already moulded.

With a mini drill, I prepared the housing on the fuselage ad let a lip all around in order to glue the plug in place.

The plug is fixed in place with cyanoacrylate glue. The result is perfect and clean

The Fuselage will be equiped with the MKS DS6125-H. The servos tray is cutted for futaba S3150, I guess, but not problem for the MKS servos.

In the wing, I will use 4 DS6125 equiped with their laser cut wood frames:

The servo hole is not that big, but the frame can enter with some exercice :) !

Stay tuned !

MKS DS6125-mini and DS6125-H: 2 new kids on the block

The glider servo family manfactured by MKS is expanding with 2 new versions of the already presented DS6125 wing servos.

The MKS DS6125-mini is a shorter version of the DS6125, still with impressive specs with its aluminium case and chrome gears: Torque is a little bit lower than the DS6125 but delivers plenty of power for glider application:
Dead band:0.001ms (Default)Control System:+Pulse Width ControlWorking frequence:1520μs / 333hz(RX) Required Pulse:3.0~5.0 Volt Peak to Peak Square WaveOperating Voltage:4.8~6.0 V DC VoltsOperating Temperature Range:-10 to + 60 Degree COperating Speed (4.8V): 0.12 sec/60° degrees at no loadOperating Speed (6V): 0.1 sec/60° dagrees at no loadStall Torque (4.8V): 4.8 kg-cm ( 66.65oz/in)Stall Torque (6V): 5.8 kg-cm (81.0 oz/in)Motor Type: DC MotorPotentiometer Drive: Direct DriveDriver Type: FETBearing Type: Dual Ball BearingsGear Type: Chrome gearProgrammable: NOConnector Wire Length: 15.0 cm (5.9 in)Dimensions: 30x10x29.9 mm (1.1811X0.39X1.17 in)We…

GPS book software

With the introduction of the 2.4Ghz and onboard GPS modules, a software to load and read the GPS traces become a must have. A friend of mine developped a freeware called GPSBook that does it very well.

The development is not totally completed but the software is already usable.

It allows to:

Load and save GPS traces in various formatApply filters into GPS data loadedEdit tracks, routes, point of interestDisplay information into graphs, table or maps in 2D and 3D
GPSBook is an open source software, free and able to run on Linux, MacOS X and Windows.
More information at the following URL:

French 2011 F3F league calendar

Here is the calendar for the french F3F league 2011, plus 2 FAI and the national championship:

La Madeleine (south west / Basque Country): 2 - 3 of AprilLaurac (VKR slopes): 16 - 17 of AprilTOA (Ardéche) : 7 - 8 of MayNotre Dame De Vaulx (French Alps near Grenoble): 4 - 5 of JuneVosges (East of France)- National championship: 11, 12 and 13 of JuneLa Banne (Auvergne / Center of France): 25 - 26 of JuneCaussols (Cote d'azur)- FAI/Eurotour: 15,16 - 17 of JulyBriançon (French Alps): 30 - 31 of July FU-Menée (French Alps): 20 - 21 of AugustCol du Glandon (French Alps): 3 - 4 of SeptemberVosges(East of France): 17 - 18 of septemberLaurac (VKR slopes)- FAI/Eurotour: 30 of September, 1 - 2 of OctoberCaussols (Cote d'azur): 15 - 16 of OctoberLaurac (VKR slopes): 22 - 23 of October

The Ambrosia F3X has landed !

I received 2 days ago my Ambrosia F3X from Miro Model. This F3F model with a wingspan of 2.95m doesn't look like other plane with its crosstail, and a very original and nice planform. The section is a DP 8.3/1.66 at the root, with an evolution to a thinner section with less camber at the tip. Another particularity is the canopy that is located at the bottom of the fuselage, servos being upside down.

Characteristics are:
wingspan: 2950 mmLenght 1450 mmArea: 56.4 dm2Root chord: 250 mmsection: DP 8.3/1.66Moulding quality is absolutely superb, one of the best I have seen. The finish and fitting is just perfect. To illustrate it, just assemble the 2 wings on the fuselage with the joiner to see that there is no need to force. I will not have to sand the joiner, even a little. The fit at the root is perfect.

My Ambrosia is a glass version, the fuselage is made from kevlar carbon. The servo tray is already installed, like the control command to the tail and rudder. a small pocket with the …

Aerial pictures above Maupertuis garden

Today, during the lunck break, I flew my Gaui and did some aerial pictures in the parc close to my office in Meylan. Meylan is a commune in the Isère department in south-eastern France, a suburd of Grenoble.

Aerial Picture of the day

Picture of Grenoble taken at midday from an EasyGlider equiped with a Sony Cybershot W350. Grenoble is a city in southeastern France, situated at the foot of the French Alps. Mountain sports are an important tourist attraction for the city, both in summer and in winter. Twenty large and small ski stations surround the city. In the background you can see the Vercors.

More information can be found on Wikipedia

A new fresh and beautiful video from Jean-Claude Gonnin

Jean-Claude is very good to share with us the beauty of Spain. This time is no exception with this new onboard video taken above Peñiscola.

Enjoy !

2 new amazing videos from Team Black Sheep

You have probably seen their film series called "Living FPV". I propose you today 2 new amazing videos. The first one is "just" the immersion world record with 47 km !!!! they use a flying wing for that:

Very long range from RiSCyD : TeamBlackSheep on Vimeo.

I personnaly prefer the second one which is absolutely superb. An immersion flight in patrol with a 8.4 m ASH31 sailplane !!! Using the Go Pro I can tell you that the flying wing is very very close to the sailplane !

Glider Formation FPV from RiSCyD : TeamBlackSheep on Vimeo.

RCRCM Typhoon Full Review (In French)

Full review in French of the Typhoon from RCRCM. The Typhoon is a 2m slope allrounder: Read the article.
Review in English is here.

Opale Paramodels Spiral 1.2 Full Review (in French)

Full review (in french) of the RC Paraglider from Opale Paramodels: Read the article