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Sunday, October 27, 2013

Col de Faisses, N115 and Mobius

With fall arriving, the slope season is ending here in Europe. However, last week-end, we had superb condition with cool temperatures and good south wind. I drove to Col de Faisses in order to fly the Needle 115, and also do a video and some aerial pictures with the Mobius action cam. The place is wild and beautiful so perfect for this exercice. 

We flew almost 3 hours non-stop, with or without the cam, and moving the cam between the wing tip and the center to obtain different perspectives.

After some quick editing, this gives the following video. The camera filmed in 1080p, but the editing output is 720p for upload and file size reasons. But it gives a good idea of the quality you can expect from this excellent tiny Mobius cam.

Despite I had also the Pike Precision and the Needle 100, I flew only the Needle 115, and enjoyed it a lot in a medium wind (9 to 10 m/s I would say). I flew with 700 of ballast all the time. 
Below is a video taken with the GoPro3 mounted on the helmet. You can see the good speed the N115 can achieve, and also how well it tracks, thanks to the cross tail / fin.

Laurac, last comp of the french league

Last week-end was the last contest of the french league which includes 13 competitions from March to end of october. Over these 13 competitions, 3 has not been validated because of the weather.
Before the last competition, scores were very close and 3 to 4 pilots could still win the league. I arrived on Friday to fly all the afternoon, and push the testing of the gyro on my Pike Precision in strong conditions before the comp, as the organiser added a local rule allowing gyros, in order to really know if it was giving a clear advantage. During that time people continue to fight on RCgroups forum without having flown at least 1 flight with a gyro onboard :) !

the wind was really strong on Friday, with an average of 70 km/h, with some cross wind, as usual for this VKR2010 slope A of Laurac. I flew the Pike alternatively with and without the gyro activated, then flew the Needle 115, then switched back to the Pike. At the beginning, I had to reduce the gain to 30 or 40% because this time the plane was oscillating at high speed. Once tuned properly, I found the plane to be very stable in trajectory. It was interresting to see the automatic correction at the ailerons when facing the wind. But something was curious. I had the impression that the plane was not accelerating. When deactivating the gyro, I could feel the speed coming back, even if the plane was a little bit less stable. My conclusion is that the high rate correction on the ailerons are making the airfoils to not working properly, and because it is our engine, its efficiency is finally worse. This is a shame because this is typically the turbulent conditions were the gyro could help.
Decision to not use the gyro for the competition was taken at the end of the afternoon, as I prefered to use a stable plane, than to take the risk to decrease the speed.
On Saturday, all the pilots met before midday, and the course has been set quickly by the organiser. We started the competition in a good wind, but not as strong as Friday.  We managed 6 rounds before clouds go down, but anyway, it was late so we had to stop. At the end of the day, I was leading the comp by a good margin, followed by Allan Cohen who flew the best time of the day with 39s, and Cedric, then Matthieu.
sunday morning, after an huge storm in the early morning, we arrived on the slope and discovered that the wind was parallel to the slope. We waited until midday, and resume the competition. But before we could complete the round, low clouds went again, and we had to cancel the round after the usual 30 minutes wait. We started again later, with very variable conditions between cross wind and thermal. At that game Matthieu won the 2 rounds we could complete before the end of the comp, piloting his FS3 very accurately and jumped from the 4th place to the 2 place of the final ranking. Allan finished 3rd and Cedric 4th. I could keep my 1st place in the ranking, and won the competition.

For the anecdote, only one pilot had a gyro on board during the whole competition, but not activated, and he got a zero after its initialisation went bad and lost both ailerons. He landed safely without too much problem but with a zero ("If you use a gyro, a zero you will get").

I flew the N115 all the week-end  despite I continue to discover it: how and when to ballast, how much compared to other plane, Snap flaps settings, reflex camber, CoG, etc ... But the Needle did the job flawlessly and I'm very satisfied. The Needle demonstrated to be be very stable in such turbulent condition with some reflex camber, keeping its grip in turn. Because of the lower thickness of the airfoil, I needed less ballast that other plane, flying with 1.1kg, then 800g, when other was at 1.5 to 1.8 kg. This win allowed me to win my 11th F3F French League over 14 years (The league has been created in 2000). Overall, 2013 has been a good season for me with the french F3F champion title, the league, and the first place at the national team qualifier.

Below is a video of 3 rounds with my Needle 115.

Needle 115 in action from Pierre Rondel on Vimeo.

Wednesday, October 16, 2013

Mobius Cam ... the GoPro killer ?


Have you have seen on Planet Soaring, I'm a fan of on-board cam, and also aerial pictures. I have started years ago with a basic 640x480 resolution cam. Then I purchased the GOPRo1, and more recently the GoPro Hero 3 to benefit of the progress in term of resolution and features. But the problem of the GoPro series is that it is not suitable for mounting it on a small to medium glider because of the size and the weight. Therefore, I gave a try to the Keycam 808#16 V2 Lens D which provide 720p video with fish eye effect, in a very small size and weight of 20g, in brief the ideal cam to mount everywhere on a glider without impacting the flight too much. To be honest, I like very much the view from the wing tip where you can see the entire plane, and of course the scenery behind. This year appeared on the market a new cam which is the result of the collaboration between the designer/manufacturer of the keycam 808#16, and several aero-modellers. This is a superb and efficient cam, highly configurable but also firmware upgradeable that I propose to present you today.


The Mobius has a modern and square case design made of precision molded of rugged high-density plastic. On the top, it has 3 buttons (power, mode, shutter) and a multicolor LED that allow to know in which mode you are (1 color per mode), and the state of the cam (flashing = recording). Two large exposed metal heat sink surfaces protruding through the case heat dissipation from the DSP and memory chips. On the rear side of the case, we find the Mini USB port, used for charging the battery and communicate with the cam (GUI, or external USB disk), and 2 tiny holes for the reset button, and the recording LED. The front side host the lenes (hopefully) that is provided with a cap, and the microphone hole. On the bottom side, we find only the access holes to the 2 case screws. The camera weighs approximately 40 grams (without the lens cap) and dimensions are the following: 61mm (Length) x 35mm (Wide) x18mm (Height).

The lens mounted on the Mobius is a medium FOV (110°) lens that provides some fish-eye effect at 1080p resolution, but less that the Keycam 808#16 V2 Lens D or the GoPro. I found it to be a good compromise.

The Mobius come with a cable (USB, mini-USB), a tiny Allen wrench to open the case if needed, a piece of Velcro tape, and an interesting mount equipped with a standard 1/4-20 photo tripod thread.

Let's have a look to the features and functions of this Mobius, and this is where things are becoming interesting:

The mobius has two user selectable video modes (configurable), and one photo mode, configurable too. So on the field you can switch easily from one mode to another depending of your needs.

Video mode proposes the following settings:

  •     3 resolution / fps settings  : 1080p-30fps or 720p-60fps or 720p-30fps (MOV  H.264 compression video format with )
  •     3 quality settings (Super, Standard, and Low) that affect the bit rates (from 18,000 kbps down to 5,800 kbps)
  •     high dynamic range function
  •     5 recording times :3, 5, 10, and 15 min. plus "Max" which correspond to the record until reaching 4 Gb (depending of the micro SD card)
  •     Loop recording, which means that once the micro SD card is full of clips, the mobius will overwrite the oldest file and continue to record
  •     movie orientation (180 deg. rotation) to record when the mobius is mounted upside down
  •     sound on/off
  •     Movie time stamp toggle

Photo settings are:

  •     Photo resolution: 2304x1536 , 1920x1080, or 1280x720 pixels
  •     Time Lapse delays .25s or .5s (at 1920x1080 resolution max), and 1, 2, 5, 10, 30 and 60 second intervals
  •     Photo time stamp toggle

Cam settings

  •     Power on button delay (to prevent premature activation while handling)
  •     auto power off (inactivity)
  •     Auto-record when power to the camera is applied (useful for car recorder use - no button presses needed.)
  •     Charging on/off toggle when plugged into a USB data port (useful for some external USB devices)
  •     TV out (PAL or NTSC), which includes a playback mode with audio.
  •     TV display ratio (4:3 or 16:9)

There are two ways to configure the mobius and both are very easy. The first one that we will call "manual" consist in writing the current config on the SD card, then modify the text config file, and then reload it. The smart things is that the cam remove the conf file from the SD after reading it, so you are sure that the configuration has been taken into account. Below is an example of the config file, so you can see exactly all parameters, current alues used by the camera are shown in bold in the square brackets, and the rest of the line describe possible values and their meaning:

    Date time=[2013/06/28-21:33:34];date time setting,format yyyy/mm/dd hh:mm:ss

    Video Mode 1 resolution=[0];Movie resolution setting,0:1080p,1:720p
    Video Mode 1 Frame Rate=[2];Movie frame rate setting,1:60fps (only for 720p), 2:30fps
    Video Mode 2 resolution=[1];Movie resolution setting,0:1080p,1:720p
    Video Mode 2 Frame Rate=[1];Movie frame rate setting,1:60fps (only for 720p),2:30fps

    Photo Mode Capture Size=[0];set photo size,0:2304x1536,1:1920x1080,2:1280x720
    Set Time Lapse Shooting=[0],0:off,1:0.25s,2:0.5s,3:1s,4:2s,5:5s,6:10s,7:30s,8:60s

    Movie cycle time=[2];movie cycle time,0:3 minutes,1:5 minutes,2:10 minutes,3:15 minutes,4:max to 4G byte,
    Movie Loop Recording=[0];set loop recording on or off,0:off,1:on,
    Time stamp=[1];set date/time stamp on or off,0:off,1:on,
    Movie sound=[1];set movie sound,0:mute,1:on,
    Movie Flip=[0];set movie rotate,0:off,1:on,
    Movie quality=[1];set movie quality, set movie data rate,0:Super,1:Standard,2:Low,
    Movie high dynamic range=[0];set movie high dynamic range,0:off,1:on,

    Power on=[1];set system power on time,0:delay,1:fast
    Power off=[1];set system auto power off time when system pending,0:off,1:30 seconds,2:1 minutes,3:2 minutes,
    Auto Record=[0];set connect or disconnect with power to start or stop video recording automatically,,0:off,1:on,
    LED=[1];set LED flicker when recording,0:off,1:on,
    Charge from USB Host=[0]; when connecting with USB host, charge camera or not,0:on,1:off

    TV out=[0];set Tv out,0:NTSC,1:PAL,
    TV Display Ratio=[0];set display ratio,0:4*3,1:16*9

    {TLCAM MOV:2013/06/25 v0.32}

The second way is using the Windows or Android GUI connected to the Mobius and select various options/features on the GUI, then apply. I haven't checked the Android GUI yet because I have an old Galaxy S2 with an old version of Android on it. But clearly, the possibility to configured your cam with your smart-phone is really a great plus.
Both ways are also applicable to upgrade the firmware of the cam to benefit of the latest version/bug fixes/features. I flashed mine manually, and it worked great.

At the field: First of all, I found the Mobius format and size ideal for our needs. You can bring it everywhere because of it's tiny size, you can wear it on a cap because it is light, where it is preferable to have an helmet for the Go Pro. But the primary use of the Mobius is obviously on-board, On the front of the fuselage, for FPV thanks to it's video output, in the wing tip to obtain spectacular view angles, etc ... or simply  mounted on a compact/light/cheap quadricopter. In brief, this is the perfect on-board cam. Operating the Mobius at the field is pretty easy. Leds are well visible, buttons works well and are clearly identified. For aerial pictures, I selected the timelapse feature with 1 pitcure every 2 seconds. This is a good compromise, especially if you have a large storage 16 or 32 Gb Micro SD. In other words, I'm impressed !

In conclusion, this little cam is, from my point of view, more adapted to our hobby than the expensive GoPro Hero 3. The Mobius is well designed, well thought and provide high quality pictures and video comparable with a 6 times more expensive cam. I definitively recommend it. Personally, I will keep my GoPro 3 on my helmet, sell the GoPro 1 that I still have, and use from now the Mobius at the smallest occasion.

Below are some examples both in video and picture mode, taken on-board to give you an idea of the quality. In addition, there are many video sample on the web. I will publish more video and pictures as soon as Mr Sun shines again (Summer is obviously finished).

The first picture is from Gérard (http://www.geeby22.fr/) who uses the Mobius for few weeks already.

Courtesy of  Geeby22

The second  picture is from me using my Easystar2. This is the original file, not resize or touched.

And finally here an onboard video at 1080p 30fps. This is Joel Marin Mobius mounted at the wing tip of my Pike Precision.

The Mobius can be purchased in Europe at Flash-RC.

As soon as I take more aerial pictures and video, I will share them with you of course !

Tuesday, October 15, 2013

techno explained

For those who are curious about technology and who wanted to learn more about how a MEMs gyro works, here is an interresting reading. click HERE to download the PDF document.

Hereafter also is a quick view about how it works:

Monday, October 14, 2013

Some feedbacks about the use of the Gyro at slope

Below are my first feedbacks after trying the Eagle Tree Guardian gyro on my Pike Precision. It is mounted only on ailerons, all other servos are connected directly to the receiver. I did this for 2 reasons:

1/ Consumption: Without re-cabling everything, there is only one + and one - wires to power the gyro and the 4 servos behind the gyro. Given the consumption of the digital servos, I didn't want to take any risk.

2/ V-tail mixing. When using a gyro, the V-tail mixing MUST be performed by the gyro itself, and not by the radio. Therefore you loose the mixing/tuning features of the radio.

Last week, I did a first attempt that was a failure because my gyro had the heading lock feature enabled causing the glider to exit the bank and yank or EM turn by itself, like the beginning of a dynamic stall. I suspect the gyro to think on the 3 axis together and combine the reaction , and because I had only the ailerons connected, it created some side effect.

Anyway, for the second attempt yesterday, I applied the following settings

  •     Refresh frequency: 100 Hz (instead of the default 50 Hz)
  •     Heading Lock disabled
  •     3D Rate Control disabled
  •     Gain at 35% on the potentiometer

Flying conditions were very light, and I had to fight to climb. While thermaling, the glider was stable, but it is anyway without gyro, so no real difference. I played with the activation/deactivation of the gyro, and I didn't see real benefits.

For the second flight, I increased the gain to 60% on the potentiometer, and didn't touch other parameters. The glider was more stable, especially at cruise speed or at higher speed. But on another hand, it was very heavy at the sticks, like I had very heavy wings. It became a problem during turn exit because I needed more counter action on the ailerons. I suspect the gyro in the mode to

I landed in order to changed some parameters, and especially to active the "3D Rate Control" which seems to be a specific feature to the Eagle Tree Guardian, according to the use manual. With the mode enabled, the gyro translate sticks movement into angular rate. The objective is to keep the agility/responsiveness on the roll axis, while keeping stability.

    Direct Rate 3D Control Submode
    Unlike many other gyro stabilization systems, the Guardian employs Direct Rate 3D Control to translate your stick deflections to angular rates without forcing you to “fight the gyro.” With this feature enabled, the Guardian interprets your stick deflections as commanded angular rates and attempts to have your model follow those commands. This way, snap rolls and other high speed maneuvers are possible without compromising on stabilization effects. 

So I ended with the following settings:

  •     Refresh frequency: 100 hz (instead of the default 50 Hz)
  •     Heading Lock disabled
  •     3D Rate Control enabled
  •     Gain at 100%

With these settings, I retrieved the agility/responsiveness on the roll axis. In rapid transition, the gyro was keeping the glider very stable, I had less correction to do. Turn exit were as before, without gyro.

In fact I notice that, in the gyro mode, the stabilization is lower at low speed, which is nos masking lift changes. The action of the gyro is visible at medium to high speed.

Now the real gain is, from my point of view, not determinant in the flying conditions I had. I think it will be more interresting to see it in stronger wind with turbulences. In that case the gyro will work more and be more visible on trajectories.

Another observation: While playing with parameters in the workshop, I noticed that increasing the refresh frequency was making the gyro more reactive. This is only possible when using digital servos, and it is important to check the frequency at which they work. MKS servos are at 333 Hz, so I have some margin when using 100 Hz. On the gain value side, I finished at 100% and didn't notice any oscillation in flight. It could be due to the fast refresh rate that make the reaction loop super fast.

Last point about the sensation at the sticks. Once the gyro properly tuned, I had full sensation at the sticks, absolutely no difference while thermalling or while doing laps. I still need to place the plane on the right trajectory, adjust the turn, choose the turn technique, etc ...

Next test this week-end if weather permits. Stay tuned !

Sunday, October 13, 2013

Gyro ... text explanation ...

After my  posts about this topic, I received lots of questions/comments regarding the reason why I agree now that Gyro are prohibited. Problem of this controversy and debate is that most of people are mixing their personal wish and are failing to analyze the text itself. They don't read the text as it is, they don't analyze the wording. A good example is when you ask the question: Do you think that the current rules allow or ban the use of gyros ? The answer is "I'M AGAINST GYROS !" which is obviously not answering the question. "Yes maybe but I don't care, I'm against" they repeat! This will not make things to progress for sure !

So let's your opinion aside, and please have a factual look at the current rules.First observation: Model definition differs between F3B, F3J and F3F

F3B  Definition of a Radio Controlled Glider
Model aircraft which is not provided with a propulsion device and in which lift is generated by aerodynamic forces acting on surfaces remaining fixed in flight, except control surfaces. Model aircraft with variable geometry or area must comply with the specification when the surfaces are in maximum and minimum extended mode. The model aircraft must be controlled by the competitor on the ground using radio control. Any variation of geometry or area must be actuated at distance by radio control.

F3J  Definition of a Radio Controlled Glider
A model aircraft which is not provided with a propulsion device and in which lift is generated by aerodynamic forces acting on surfaces remaining fixed. Model aircraft with variable geometry or area must comply with the specification when the surfaces are in maximum and minimum extended mode. The model aircraft must be controlled by the competitor on the ground using radio control. Any variation of geometry or area must be actuated at distance by radio.


5.8.2.  Characteristics of Radio Controlled Slope Gliders
Maximum surface area (St)............................... 150 dm2
Maximum flying mass . ....................................... 5 kg
Loading on St ..................................................... between 12 and 75 g/dm2
Minimum radius of fuselage nose 7.5 mm in all orientations (see F3B nose definition for measuring technique).

The radio shall be able to operate simultaneously with other equipment at the normally used spacing in the allocated R/C bands (i.e. 35 MHz : 10 kHz). The competitor may use three models in the contest. The competitor may combine the parts of the models between the rounds provided the resulting model used for flight conforms to the rules and that the parts have been checked before the start of the contest. Addition of ballast (which must be located internally in the model) and/or change  of angles of setting are allowed. Variation of geometry or area is allowed only if it is actuated at distance by radio control.

For F3B and F3J the important sentence is:

"The model aircraft must be controlled by the competitor on the ground using radio control. Any variation of geometry or area must be actuated at distance by radio control."

First point: Control surfaces movement are not part of the geometry/area variation as per aeronautics definition (source aeronautics engineers). In fact this sentence  has been written to cover the possibility to heavily change the glider properties (wingspan, section, root chord) between duration and speed task that requires totally different plane in theory. A good exemple is Ralf Decker's Tele-F

Second point: model aircraft must be controlled by the competitor on the ground using radio control

A gyro is not controlling the model aircraft, it is stabilizing it. If you don't pilot your glider, he will simply crash. With or without gyro, the pilot is the only person controlling the plane. The "hole" comes from the fact that the rules refers to the model, not to the control surfaces. Gyro controls the surface, not the aircraft. So this sentence is not clear enough and allows the use of Gyro. A Simple change could be: "model aircraft control surfaces must be controlled by the competitor on the ground using radio control".

Now, F3F glider definition is even less precise as the sentence "model aircraft must be controlled by the competitor on the ground using radio control" doesn't appear which would mean that something/somebody else than the pilot could control/pilot the plane !!!

So based only on the rules,, 5.8.2. I'm considering that the gyro is allowed, and for F3F, we could even consider to install an autopilot (OK, stupid idea I recognize!).

Now there is another general section in the FAI rules that defines categories:

1.3.3. Category F3 - Radio Controlled Flight

This is a flight during which the model aircraft is maneuvered by control surface(s) in attitude, direction and altitude by the flier on the ground using radio control.

For me this sentence is much clearer, because it says that control surfaces must be actuated by the flier on the ground using a radio control. This make a big difference as any on-board devices acting on the control surfaces in the back of the pilot is therefore prohibited, which is the case of a gyro.

This is because of this sentence that I changed my mind, and now agree that Gyro is forbidden in the current rules. However, I still think that it would be good that the CIAM write a recommendation/statement to make things even clearer.

Update: another rule in the Section 4C says it all as the model aircraft must be in direct control of the flier. this rule cannot be more explicit.

Now, the debate to know if it must be authorize in the future is another question. To be honest, I have a mixed feeling about that subject as they are good arguments on both sides.

For the moment, I will test a gyro in sport flying to see if they are real benefits on a sailplane at the slope. I'm considering to use it in the future on a aerobatic glider. I will keep you updated

Friday, October 11, 2013

Gyros ... important update !

Since the debate around gyros started, almost 2 weeks ago, we were all focusing on the various category specific sections, as mentioned in Tomas’s email to CIAM delegates. It is obvious that these rules were everything but clear. A rules which is subject to interpretation is a bad rule …

But while debating/fighting we just missed another general section (pointed by Tom Kiesling and Mike Evans) that describes the categories included in the F3 category (Radio Controlled Flight).  And in this section, one sentence says it all as you can judge by yourself.

1.3.3. Category F3 - Radio Controlled Flight 

This is a flight during which the model aircraft is manoeuvred by control surface(s) in attitude, direction and altitude by the flier on the ground using radio control. 


And here, this is explicit. Any device able to actuate control surfaces independently of the flier is forbidden. So gyros, stabilization systems, autopilots are prohibited.

It is good that we finally clarified the situation that was very unconfortable from my point of view. It will be easier for the CIAM sub commitee to do a clear recommendation.

Thursday, October 10, 2013

Gyro in F3x ... things are finally moving a bit !

Thanks to Roman Vojtěch (http://lomcovak.cz/wp_eng/), who relayed the RCgroups debate about the use of gyros in F3B/J/F and expressed his concerned to Tomás Bartovsky who is the Czech Rep. NAC FAI CIAM Delegate but also the RC Soaring Sub-committee chairman. Tomás sent a letter to all NAC FAI CIAM delegates asking to answer a simple question about what is their interpretation of the current rules. The letter is hereafter.

Dear Friends,

At present we experience a kind of technical revolution. The electronic stabilisation devices (hereinafter gyros), which were not working well in the past, are today effective, cheap and readily available. Many years ago, when rules for F3B, F3J and F3F classes were created, the authors could not imagine the development of electronic stabilisation devices. For this reason we have an unsatisfactory description of allowed means in the FAI Sporting Code at present. The German proposal for general banning of gyros, which was prepared for clarification of the unhappy situation, was not accepted at the last CIAM Plenary Meeting. We now live with the doubtful wording of the F3B, F3J and F3F rules and need an early clarification. Unfortunately decisions may be taken only by the CIAM Plenary Meeting or by the International Jury. Both decisions concerning the gyros would be too late. CIAM Plenary Meeting needs more than one year (Rule Freeze not included) for processing of a proposal.  The International Jury has the right to interpret such rules which are not quite clear, but it may act only at the competition. Such decision is too late for competitors who must prepare their models and piloting skill much, much earlier. 

The CIAM FAI Subcommittee has no right to take such decision, because the International Jury is independent, bound only by the FAI Sporting Code and higher FAI Documents. Still I believe that the CIAM FAI Subcommittee may prepare a recommendation which, at our present situation with the gyros, is very necessary. Therefore please send me your opinion concerning the interpretation of the relevant paragraphs in the RC Soaring Volume of the FAI Sporting Code.

According to paragraph
(Definition of a Radio Controlled Glider: Model aircraft which is not provided with a propulsion device and in which lift is generated by aerodynamic forces acting on surfaces remaining fixed in flight, except control surfaces. Model aircraft with variable geometry or area must comply with the specification when the surfaces are in maximum and minimum extended mode. The model aircraft must be controlled by the competitor on the ground using radio control. Any variation of geometry or area must be actuated at distance by radio control.) 

-> the electronic stabilisation devices are allowed       forbidden

According to paragraph
(Definition of a Radio Controlled Glider: A model aircraft which is not provided with a propulsion device and in which lift is generated by aerodynamic forces acting on surfaces remaining fixed. Model aircraft with variable geometry or area must comply with the specification when the surfaces are in maximum and minimum extended mode. The model aircraft must be controlled by the competitor on the ground using radio control. Any variation of geometry or area must be actuated at distance by radio.)

->  the electronic stabilisation devices are allowed       forbidden

According to paragraph 5.8.2.
(Characteristics of Radio Controlled Slope Gliders: …Addition of ballast (which must be located internally in the model) and/or change of angles of setting are allowed. Variation of geometry or area is allowed only if it is actuated at distance by radio control…)

-> the electronic stabilisation devices are allowed       forbidden

By ensuring that each country answers to the survey, this will higlight the need of a clarification of the rules.

I invit you also to read the experiment Roman did with an Eagle Tree Gyro yesterday on his Stinger. The outcome is quite interresting.

I really hope that things will finally move one direction or another, then we can smoothly prepare the next WC, and have a crystal clear rule about stabilization devices.

Gyro or not Gyro ? ... get ready !!

The F3x community is currently boiling  while discussing the topic about gyros on RCgroups. There are three camps: the "anti-gyro", the "pro-gyro", and the "I don't mind about gyro" camps. 

How did it come on the table?

Suspicion about using gyros in F3x gliders started during the 2012 F3F World Championship in Rügen, Germany. For some pilots, the supremacy of the leading pilots was suspect. However, no protest has been written during the competition, but I heard that a claim deposit has been done later to the CIAM. At the end of the season, a German rule change proposal to ban gyros has been rejected by the CIAM. At this stage it was not clear if it was rejected because of a bad wording, because of a wrong place in the rules, or for some other reasons. Few weeks ago, some info came after an F3B competition that gyros were authorized, and that some top pilots were using them. As usual, if it is confirmed, people using gyros will stay quiet and not claim publicly that they are using it. 

It is only recently that we understood that the CIAM was not in favor to ban gyro, because it was considering it as progress for the categories that could encourage young pilots to join. For example the answer from Tomas BARTOVSKY (CIAM's RC Soaring Sub-Committee) to the question (whether or not gyros are allowed in F3F or F3J by the Sporting Code) is the following:

"The situation seems to be cleared after the CIAM Plenary Meeting this year. There was a German proposal for banning gyros in all classes except where the rules of the class allows them. This proposal was rejected. Many people expressed their opinion that young people love new technologies and therefore the gyros should not be banned. Nobody stated that the gyros are banned by the present wording.

The term "direct control" is not sufficiently clear for excluding all stabilisation systems, and if the clear banning of gyros was not accepted by the delegates, to my opinion the gyros are allowed for RC gliders."

And on the FAI website (http://www.fai.org/ciam-news/37176-main-decisions-2013-ciam-meeting) you can see that the debate around the question occurred (during the Friday evening’s Open Forum discussion at the plenary meeting) and that the position is rather clear:

"prohibiting the use of technical aids (gyros, telemetry etc.) when it was considered that most young flyers enjoy the use of such technology. Resisting change and remaining with long time existing regulations was seen as a barrier to new entrants"

It is not new that the F3F rules are plenty of "holes". Remember 2002 in Slovakia, where we discovered the diving. Of course it was not in the spirit, but at the end it was legal, and most of the other competitors tried to dive in order to stay in the race, myself included! I have in mind some particular other points like reflights, or groups scoring, but there are probably some others. In fact there are many things to clarify.

Then comes the question of fairness/equity, as this is considered by some people like opening the Pandora box to authorize gyros or any stabilization devices. According to them, we will soon see much more complex devices looking like autopilot, with waypoints, sensors everywhere, flight path optimization, etc … Of course this is not impossible, but certainly not from day one, and the CIAM can decide anytime to stop/control/block, just by defining clear rules.

Now, please consider the following question: are pilots equal during a competition even without gyros? Definitively not!  In all F3x categories I know competitors who have access to resources/tools/equipment (super computers, wind tunnels, CAM DAM, 3D computation, etc.) that others don't have. Some competitors work for the aeronautic industry, having deep knowledge in aerodynamics. They are able to design entirely a plane, build it, optimize it, etc.Some others have very tight relationship with manufacturers, so they have access to prototypes, or special layout. Is it a problem? From my point of view, no, because finally this is the dynamic of the competition. Competition is not only about comparing flying skills, it is in fact much more. This all makes the discipline to progress, and then all the evolution is being retrofitted in sport flying machine.

Gyro prices start at 17$ so is accessible to everybody (you can now buy a beginner plane with built-in gyro), at the opposite of the best F3x frames that are sometimes far too expensive or far too long to obtain. Ultimately, the only way to guarantee a total fairness would be to fly F3F on CRRCSIM simulator with the same plane, the same virtual wind condition. Is it what we all want?

Safety issue? I read on RCgroups some ridiculous argument saying that gyros are not safe on a slope because they may fail and they should therefore be prohibited. Today there are more risks to have an accident because of a radio failure or battery failure than a gyro failure. 
Another big challenge if we decide to ban gyros is the enforcement of the rule. Today, for less than 100 euros, you can have an 8 channels receiver with built-in gyro, and even vario (despite telemetry is explicitly forbidden in the rules). How will the organizer check that, at any time of a competition? This is nearly impossible.

So what is next?

Personally, I fly slope soaring for 34 years, and F3F for 20 years. I have never used any gyro in my gliders. I recently purchased one for my electro airplanes (MPX twister, and Easystar for aerial photography).
I don't have any religion about gyros (I'm in the "I don't mind about gyro" camp). I've never felt the need of it, but on the other hand, 3 axis gyros are rather recent. Now I'm a competitor, and the simple fact to know that it is not forbidden to use a gyro in an F3x plane and that some pilots may have already used it or will for sure use it from now, made me take the decision at least to try. 

Hopefully, whatever the benefit of a gyro, it is easy and transparent to install or remove in a glider (except for the space it takes, considering the small place we have in the fuselage), and settings are totally independent of the radio settings.
If tomorrow the CIAM decides to ban gyro in F3F (note: for F3F any rule change decision in 2014 will take effect in January 2016 only), great, no problem. If it is the contrary, I will be ready, I will have experimented, I will know the PROS, the CONS, and the gyro will be correctly tuned. This is what we call COMPETITION. Am I wrong? 

What I'm fighting for, is to have a clear rule that everybody knows in advance, not during the Team Manager meeting prior to the competition, stating that gyros are forbidden or are authorized. This is simple, can be done, as suggested by my Spanish friend Alvaro Silgado, as a simple local rule. But it must be announced in advance. Then I am convinced we will adapt.

Friday, October 4, 2013

Book: RC Aero Design, aerodynamics for everyone

Few words about the writer: Franck Aguerre is engineer by education, but is also an aeromodeller for ages, and writer for specialized paper magazines. He is a very active  designer who created lots of models (some have been published) which became very popular like the Crobe, a best seller now available in short kit. Franck is also the author of the PredimRC software, available in 2 version (one is freeware, the second one with more features being commercial). After writing many technical articles about aerodynamics and aeromodel design, Franck decided to go to the next step by rpoposing use this book RC Aero Design.

152 pages to know everything !

The book is presented under at the A5 format with a soft cover. The printing quality is excellent, with lots of sketches and drawings which illustrate the text. The few pictures here and there are not as good, the paper being not glossy. Overall, this book is very good printing quality, at the level of the ones sold by the large printing companies. Congratulation to Laurent Michelet for this first publication which is a success !

After looking quickly about the support, let's see the most interresting part, the content: RC Aero Design is a popularization book which allows to everyone to better understand flight mechanics by proposing 2 parts, the first one to explain the basis, the second to describe step by step the methodology of the aeromodel design.

The first part is about 20 pages long, and address base concepts to better catch aerodymanics principles, like vocabulary, how to create lift, the reynolds number, the center of gravity, trail, induced trail. For some of you it will be new, and for some others, it will  make a good reminder.

The second part, much longer, go deeper in details, and propose a well structured path that starts with requirements, the drawing of the planform and the choice of the airfoil, after a good explanation about how to read a polar, the design of the fuselage, the tailplanes, the interactions between the differents components, the angle of incidence, etc ...
Then Franck gives some information about the design of the control surfaces, with some details about mechanics and cinematics.
A big part is then dedicated to the flying performance analysis, starting from the basic diving test to the more complex use of flaps, snapflaps, the influence of the wing loading.  A section is also dedicated to the motorisation, but we feel first that this book is written by a RC glider pilot for glider pilots, and I will not complain about that !

Along the book, we see from the author the concern to explain simply and clearly things. And this allows to have several level of reading, from the almost beginner to the expert pilot, because everyone will find what he is looking for. There is no need to read the book entirely in one time, but instead you can just read and understand a section, a paragraph, a chapter, depending of what question you have, or the problem you encountered. I do believe that this is the best way to appreciate this book and remember what you have read.

In conclusion, this is the type of book you buy and keep forever, as a reference you can rely on. Then, nothing prevent to dig a bit a particular point and go info fishing elsewhere. RC Aero Design has the big advantage to group lots of things, clearly explained, in a compact format. So if you read french and don't have this book yet, you know what to do ! Ordering it is very easy thanks to the RC pilot website.

Publisher : KoolPress. 152 pages, A5 Format, soft cover, Price 25 €. 

F3G and F3B in Kulmbach / Germany, a tradition continues!

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