Friday, March 30, 2012

Planet-Soaring blogspot passed half million visits

Since I migrated to Blogspot very end of 2009, Planet-Soaring just passed the half million visits. This is a good achievement considering the fact that it is not a professional website. But it is still an huge amount of work and this statitistcs and all the encouragement I get is great rewards for me.


EasyStar 2 RR review in Modèle Magazine

My review of the EasyStar 2 RR has been published in the french specialized magazine "Modèle Magazine". It is a 5 pages article, and the pictures look great, thanks to the photographer Vijay Balasegaram, my work mate.


Monday, March 19, 2012

Willow F3F with 700g of Ballast


Last Saturday, before the bad weather reaches east of France where I live, I drove to a slope to enjoy the sunny weather and the south wind (about 30 km/h) and try the Willow with some ballast.

During all the afternoon, I used 700g of ballast (which was the maximum I had with me. Now I can go to 900g). Ballasted, the Willow felt still light on the stick, and didn't show any noticeable bending of the wing which is a good point. I tried different turn styles with no difficulties. The Willow likes the "half roll and pull" where agility is a plus. In EM, it is fine but not superior like some planes where the section especially contributes to the acceleration with load of ballast like the Alliaj HM or the Pike Precision (to compare with planes I know well). Gain of altitude was great and the thermal position of the flaps+ailerons works good.

Speed position bring also some additional speed, but needs a bit more snapflaps to compensate the lower camber of the section for equivalent grip during the turn.

I really enjoyed this afternoon, and people present on the slope appreciated Willow capabilities. Nicolas even tried it for few minutes and really was surprised by the agility of the plane compared to his F3F model.

I did some nice footages with my GoPro I fixed on the plane. Vimeo is always slow in the evening, so I couldn't upload the video. Tomorow morning should be OK.

Wednesday, March 14, 2012

TBS: the road trip continues ...

And Team black sheep posted 2 fantastic videos superbly edited, with a nice music, in brief a great moment. The first one is filmed around the lake powell located on the Colorado River:





The second video is shooted on the california coast, near Pescadero at the Pigeon Point Lighthouse
 

Monday, March 12, 2012

Video: Willow F3F

Editing was faster than expected, so here is the video, taken this week-end:

Willow F3F maiden



Last week and this week-end, I flew the willow at my local slope in light wind condition. With 2.480g flying weight and a CG at 103, I found the plane to be good, just needed few down trim, so maybe the idal CG is at 102mm

What surprised me is that the Willow feels light at the stick. The agility on the roll axis is really great, it's grippy and precise. I followed the recommended settings for the snap flaps and elevator, and it appeared a good setting to start with. In turns, the Willow keep energy well, at the condition you don't pull too much the elevator stick. It should be good for EM turn style, as I feel could feel its potential on my "flat" slope which is not appropriated for EM.

I also has the chance of thermal while trying my new altimeter probe on my JR Propo XG8. Thermal position of the flaps+ailerons give more lift without bad behaviour. The plane clearly slows down its cruise speed. Circling is no brain, and I could gain a good 215m of altitude which is surprisingly low  compared to what I was guessing. The conclusion is that we often overestimate the altitude we fly at.

I also went to the dark side of the slope to evaluate the speed and the stiffness. The Willow accelerates well but shows its limit, especially the rear boom with no carbon reinforcement that starts to twist at high speed.

Brakes works well during approach and landing, nothing special to mention.

Overall, a good first feeling with the plane. The Willow F3F is nice to fly, light at the stick, agile, with good F3F capabilities. I need now to fly it on a cliff or sharp edge with good condition to see how it behaves.

I filmed some video sequences I now need to edit. Should be ready in few hours.

Picasa Album

Thursday, March 8, 2012

JR Propo XG8 DMSS Overview


For few monthes, JR propo is now proposing its own and proprietary 2.4 ghz system. After releasing the XG7, JR introduced second half of 2011 the XG8, a totally new 8 channels radio, and followed soon by the XG11 already presented end of 2011, and more recently at the Nuremberg toy fair in February 2012.

For this new radio, like for the 11X/DSX11, JR Propo really broke the mould and came with a very modern and innovative transmitter shape. From my knowlegde, JR gave the chance to a young designer to propose something really new. The radio looks like it is inspired by the movie "Transformers" and gives to the radio a very strong visual identity.

The XG8 is not only a nice looking radio, but is very ergonomic too: the grip is the best I've ever held. In addition with its 770g, it is very light. The position of the stick doing a opened angle with the case is ideal as a thumbs radio. It's light, It's grippy, it balances well, it's ergonomic, in brief, I like a lot. Building quality is very nice too. Despite the case is made of plastic parts, the fit and finish is beautiful, and the case seems rigid and robust, thanks to the numerous screws to close the 2 halves of the case, providing additional stiffness. 

The XG8 brings some nice features:

  • It has in the battery compartiment a SD card slot for model data sharing, expanded storage and software updates 
  • the battery is a 2 cells LiFe battery, 1400 mAh, which provides (I have not measured yet) between 3 and 4 hours operating time. 
  • The XG8 integrates a charging circuit so you just need to plug in the 9V AC/DC adapter supplied. The charging unit will shut down automatically once it detects that the battery is fully charged. No more worries overcharging! 
  • "My List" function: The XG8 provides the capabilities to create your own dedicated menu to group the functions/mixers you access the more often. This is very convenient.
  • Glider mixing capabilities: JR was known up to now to be more specialized in the helicopter. But the latest JR radios now implement specific glider capabilities.


[Glider FUNCTION LIST]

  •  Limit adjust 
  •  Flap rate: every flight mode 
  •  Motor system: with delay 
  •  Camber system 
  •  Brake system 
  •  Differential 
  •  Flaperon mix: with flap lever off set 
  •  AILE→RUDD MIX 
  •  ELEV→CANB MIX 
  •  RUDD→SPOT MIX 


[Glider SYSTEM LIST] 

  • WING TYPES: V-TAIL , 
  • Dual Elevator, 
  • Dual Flap, 
  • Dual Spoiler 


 [ETC]

  •  5 Flight modes 
  •  Dual aileron standard equipped (left:1ch/right:2ch)
I will cover more in details this part later as it is the chapter I pay attention the most !

What is DMSS ?

In the jungle of 2.4 Ghz, it becomes difficult to understand who is using what, so here is a short summary that will help you to understand:

DSSS stands for direct-sequence spread spectrum. In this method of transmission, the signal does not hop from one frequency to another but is passed through a spreading function and distributed over the entire band at once.

With FHSS, frequency-hopping spread spectrum, the frequency of the carrier is periodically modified following a specific sequence of frequencies. The amount of time spent on each hop is typically in the range of 100 ms.

JR combined the best of the two technologies into their new transmission system named DMSS (Dual Modulation Spectrum System). DMSS is a true frequency hopping based system where it hops across the entire band. In other words, DMSS is Wide band RF tansmission (like DSSS, unlike FHSS) with Frequency hoping (like FHSS, unlike DSSS). DMSS or course brings two ways communication, enabling telemetry which is a built in function in the XG8.

Wednesday, March 7, 2012

New DS World record with 498 mph

This means 801 km/h, or mach 0.65 ! This is just crazy. This new record has been established by Spencer Lisenby with a Kinetic 100. The 500 mph barrier will be broken for sure ! Congratulation to Spencer for this new achievement.

Tuesday, March 6, 2012

E-Rotmilan maiden

Last saturday, I had finally some time to fly my E-Rotmilan. And the maiden flight went bad because of my motor/esc/propeller setup. Before to fly, I did a short running in of the motor and ESC, fixing the fuselage robustly to a table in the garden. The heat schrink tube around the ESC melted after few minutes of short periods of use at a very low power (10 to 20% of the power). The ESC entered in température protection mode and stopped.




I changed the heat schrink tube before to go to the flying field. After checking everything I launch the plane without motor, then started the motor. The climb rate was good, but quickly the ESC entered in protection mode again. After that I noticed that the brake was not working, despite I programmed it using the USB link and the software Castle Link. I did few climbing but everytime the motor stop quickly, so I decided to land and return home to analyse.

Remember my post regarding the setup, with the simulation using eCalc. I finally decide to buy a 100A ESC compared to the 75A max current calculated. Looking at the data logged during the flight, we can see that we have peak to 200A, and a temperature reaching 149° Celcius. The first half is te running in, the second half is at the field, and the end of the graph is the maiden flight itself. I think I did 3 climbs.



Now the question is: Is it a faulty ESC ? a problem of cooling ? This is what I need to determine in the coming days. I will work on the cooling of the motor and the ESC creating air entries on the fuselage for the motor and on the canopy for the ESC. Concerning the brake not working, I have no idea ...

To be continued ...

Video: Team Black Sheep at Monument Valley

What a nice video in a mythic place ! This recent video from the team black sheep during their road trip in the west of USA is superb (once again ...) !


Monday, March 5, 2012

Willow build log #3

Well, Last time I stopped the build log at the moment to glue in place the inner nose with the ballast tube. This operation needs some preparation to garrantee a good positioning and aligment of the nose. I protected the parts with some transparent tape, them insert the inner nose in the nose cone with a thin plastic film in between. the fixing area of the inner noe is in fact a layer of rubber. According to the designer this is great to absorb the shocks and can still be glue with epoxy, the wood tray embrassing the ballast tube providing a deep and solid fixing into the fuselage. I used 10 minutes epoxy for this operation, then immobilized strongly the parts with more tape while drying to avoid any dis-aligment.




Lets start with control rods and servos installations. Control rods are made from 2.5mm quicklink with a metal clevise soldered on one side, and a second clevise screwed and glue on the other end, the glue is to eliminate any slop on the command. The rod is rigidified with a small piece of brass tube of the right diameter and length. All these operations are made "in situe" with the (soldered) clevise connected on the surface control horn, and with the servo in place (but not glued yet) with the servos arme at the right position, taking into account the servo travel, different between flaps and ailerons). When everything is fine, I have installed the wiring harness, connected the servos to it, then glued the servos with a kind of sealant (100kg/m2) which, once dry, can be removed with some technic. To finish the wings, I adjusted a bit the servos covers and tape them.

Let's return to the fuselage. I installed then the wiring harness in it. the routing of the wires is going under the servos tray, which is a bit acrobatic to rout, but feasible. You can decide to do the routing before gluing the servos tray. I then installed the elevator servos, cut the snakes at the right dimension, and install the 2mm adaptor for the elevator clevises. I'm a fan of MPjet plastic clevises on the servos side, as they have no slop at all.

The receiver is a JR Propo RG831B DMSS, 8 channels, and the battery made of 4 eneloop XX cells (2.5A). Because I needed lots of lead to obtain the right CG, I had to rework the front of the servos tray, in order to move backward the battery, and let more space for the lead.

I ended with a flying weight of 2480g. The willow is now ready, and at the time I'm writing these lines, I already flown it :)  so stay tuned for the next chapter !


Friday, March 2, 2012

F3F in Poland

This teaser is for the F3F FAI open organised in Poland (mid-may), and which just opened the registration. Nicely done ! You can visit the organiser website F3F 3City:

Thursday, March 1, 2012

A different perspective ...

When using Angry birds music and sounds on a F3J video, it give this ! Very funny ! Thanks Oleg :)


Pike Perfection video

Jo Grini posted a very nice video about the Pike Perfection from Samba Model, filmed with a Go Pro mounted on the winch line:

Mistral Soaring - Rognac

Yesterday we had a good friendly winter contest in Rognac, between Aix en Provence and Marseille. I left Grenoble aroudn 7am under the sn...