Aeromodellers have always been attracted by speed, if not addicted. But when you come to the speed evaluation, you quickly discover that people are very often optimistic (like measuring altitude). This is why a speed radar is interesting for our hobby.
If you don’t want to invest in an expensive radar gun, there is now a very convenient device that do the same for less money, but especially that will fit in your pocket, so that you can bring with you all the time. It has been made possible by using a much smaller, flat antenna to create the same type of signal that the horn creates in a radar gun.
I bought one for me few months ago. My objective is to have a means to measure the speed of my sailplanes when DSing.
The Pocket Radar has the size à a cell phone, and is able to measure the speed of moving objects from 11 to 600 km/h. It uses 2 standard AAA type batteries and comes with Alkaline batteries included. It comes in a very nice box that will protect it during transport.
Its accuracy is about +/- 2 km/h. If you point the radar at an object moving sideways, you won’t measure anything. This is what we usually call the Cosine error. Just remember some trigonometry when you where at school and you will quickly understand. Few figures: Within 8 degrees of angle from the moving line of the object you measure, the accuracy is about 1%, at 18 degrees it is about 5% of error, and it goes up to 30% of error with 45 degreed of angle.
The Pocket Radar is pretty easy to use: Hold the radar in your hand like a cell phone camera and simply press and release the big red button on the front of the Pocket Radar while pointing the moving object. When releasing the button, the measure will appear on the screen. If you do not release the big red button, the radar will continue to send out repeating small pulses and displaying a measure approximately every second.
You can configure the Pocket Radar with different speed units: MPH (Miles per hour), KPH(Kilometers per hour), FPS (Feet per second) and MPS (Meters per second).
To do so, just press and hold the black RECALL button. While holding the RECALL button down, press and release the big red button. Now release the RECALL button. The current selected units should blink (at the bottom of the display). Then each time you press and release the big red button, the units will advance to the next possible state (miles per hour, kilometers per hour, feet per second, meters per second).
Press and release the big red button until you see the units that you want to use blinking on the display. They will continue to cycle through each time you press the big red button. Finally, press and release the RECALL button and you will lock in the units displayed on the screen.
The Pocket Radar can store 10 measurements that you can scroll using the black “RECALL“ button.
2 Alkaline AAA batteries can provide up to 10,000 speed measurements which is not bad. The battery indicator on the LCD display will help you determine when to replace the batteries.
According to the manufacturer, the Pocket Radar can spot the speed of a car from about a 800 meters away or the speed of a baseball from up to 36 meters away.
I found the Pocket Radar to work pretty well for sailplanes. After a long dive, or while DSing, it always give a measurement. It is very seldom when it doesn’t display something.
More than that, as soon as I exit my Pocket Radar on the slope, everybody wanted to play, asking for a speed measurement of their plane.
You will see on this short video how easy it is to use the Pocket Radar:
In conclusion, the Pocket Radar is very nice device, that will cover most or our use. Of course if you are targeting the DS world record, then you will need another radar gun, factory modified to go higher than the 700 Km/h achieved today. For other pilots, the Pocket Radar give you a good progression margin before to hit its limit.
Despite cold temperatures, I spent the afternoon on the slope to fly the Ambrosia F3X in good wind conditions (Around 40 km/h). I flew it with 650gr of ballast over the 1300gr it can carry.
If I would have to describe the Ambrosia is very few words, I would definitively say: “It tracks extremely well !“. Thanks to the fin and the full moving cross tail, the Ambrosia is a pure joy to pilot. It is fast, but especially, it is easy to fly fast, which is a very good capability from my point of view. You don’t have to fight with the plane, to correct trajectories all the time.
I did hundreds of laps and turn, and I have been very impressed by its behavior in Energy Management turn style. It is so easy, remains stable, go high without slowing down. The elevator is smooth and very precise. No drag induced by a control surface, the full tail is always perfectly aligned.
The Ambrosia carried the 650gr easily, and I think I could have put more ballast without problem.
The DP section delivers very good performances, and speed. Acceleration are good and the energy retention also. The next step will be to confront the Ambrosia F3X against other gliders, to have some references and see how it is compared to competitors.
The survey ended few minutes ago and gave interesting results. Thank you all for your participation to the survey !
Before to comment the results, it is important to mention that the survey concerned mainly Europe, and especially France as you can see on these per country statistics for last month.
Let’s now have a look to the results:
Without surprise, Futaba FASST arrives in first position. FASST has been introduced at the beginning of the 2.4 Ghz, as the first FHSS system, and appeared to be reliable from day one apart few recall concerning the sensitivity to the temperature of one receiver chipset. But if Futaba represents 1/3 of the market, things could change quickly if they are not releasing the telemetry which is today the major weakpoint of their offer.
The surprise is the second rank of Jeti. Jeti was not particularly reliable with their FM receiver, but their 2.4 offer is pretty well designed, reliable, and Jeti is the very first brand to propose and deliver telemetry and various probes, not only “dream-ware”. With Jeti, telemetry is real ! Jeti is very much appreciated in the glider world. Weak point is that Jeti offers only modules and receivers, no transmitter. But they officialy announced a transmitter family for beginning of 2011.
In third position another surprise with MPX, which is very new on the market compared to some other brand. But despite a late arrival, MPX reaches 15% of the market. They offer a home made 2.4, not relying on industry chipset. As MPX is used widely by glider pilots, most of them migrated to 2.4 within the same brand.
Then we find Spektrum followed closely by Assan. Spektrum is more used by helicopter or airplane pilots, but less by glider pilots. One of the reason is the poor possibilities of the spectrum transmitter. Maybe the recent DX8 will change things. Assan, on his side is taking advantage of their aggressive pricing to take some market share. But the current trend is that Assan is slowing down because of the lack of telemetry and also transmitter. They are probably hitted by the recent progression of FrSky who proposes aggressive price AND telemetry with the interesting analog probe input on the receiver that allows to develop his own probe.
It interesting to see that “Other” represents 13% of the market. In Other we find Weatronic who recently left Graupner after the introduction of the HoTT system. We find also FrSky, and some other alternative brands.
Hitec remains marginal, which is a surprise as the Aurora 9 is a nice transmitter with plenty of Glider capabilities. In addition the Hitec 2.4 appears to be a reliable system. XPS/IFS is also marginal.
Finally Airtronics/Sanwa suffers a lot of a very poor representation/distribution in Europe and especially in France. For example, the French distributor (scientific france) is inexistent. I know that Airtronics is very popular in US and the SD10G is a good transmitter to use for gliders.
This picture of the 2.4 market will change drastically in the coming months as the war will reinforced. It will be interesting to do another survey in one year, in order to see the evolution.
Well, the weather conditions were totally calm air, no wind at all with a temperature of 4° celcius. Hopefully, all the snow melted since last week-end, so the slope was accessible.
It was defintively not a weather for a maiden flight, but because I was on the slope, I didn't want to return home without launching the plane once, do a circuit and land.
Surprisingly the first flight was longer than expected and I was able to do few circuits in dead air, with flaps, before to land, very encouraging.
I have been able to see the good lift provided by the section, and the good handling of the Ambrosia, at very low speed, with no bad habits, no stall.
Now, I'm waiting for better condition to see what the plane is capable. Maybe tomorrow I will drive 1 hour to go to another slope where the wind could blow a bit more according to the weather station installed near the slope for paraglider.
Jeti posted a press release on their website confirming the release beginning of 2011 of a 2.4 Ghz transmitter family (which means not one but several transmitters) a also a brand new slim receiver especially designed for glider nose.
This is excellent news !
By the way, don't forget to answer the survey which will give us a better undeerstanding of the market share of each manufacturer.
I thought it would be interresting to know the market share per brand, as we are in the middle of the war. Please answer honestly to the survey on the right of the page. The more I get answers, the more the result will be representative !
Lans-en-Vercors is a village in the Isère department in south-eastern France, near Grenoble. After the heavy snow falls last week, I drove there to do some aerial pictures and video. Sunny weather but freezing temperature with -8 degrees (celcius).
Lans-en-Vercors is located in the Vercors a beautiful massif of mountains. The Vercors massif and surrounding areas are protected as a regional park (Parc Naturel Régional du Vercors in French). Some especially wild and remote places of south eastern Vercors are in a more protected area named Réserve intégrale des hauts plateaux du Vercors (Vercors high plateaus reservation). These mountains were used as a natural fort by the French Resistance during the second world war.
Vercors is a perfect place for outdoor activities: Nordic Skiing (One of the largest Nordic skiing system of Europe), Alpine skiing with 7 ski resorts, Paragliding, Canyoning and Caving, base jumping, and of course aeromodelling with one of the most thrilling competition of the french cup with vertical cliffs.
This is about Sailplane but not RC. "Sailplane Grand Prix" is new gliding racing format that take advantage of the latest techonolgies to allow the spectators to watch the race real time with onboard camera, real time simulation.
The following video explain everything with in addition superb video sequences. Unfortunately, it is not broadcasted on the main channels in France. Maybe some of you have seen it