The Freewing JAS-39 Gripen is a delta wing aircraft with a canard configuration. It can also be assembled and flown in several different configurations and this makes for an interesting model. A vector thrust unit is also available as an option. You will have to make a decision before you start the assembly if you wish to incorporate the vector thrust unit into your model.
The vector thrust unit has to be fitted first. It’s glued to the front half of the fuselage in a similar way to many other Freewing and Flightline models. However, if you assemble the model as the standard version without the vector thrust unit it would be an almost impossible task to remove the standard tailpipe to fit the VT unit. My suggestion would be to have two fuselages one with the VT unit and one without if you first assemble the model in its standard form. The VT unit also requires 2 extra channels on the transmitter and the receiver to operate it, and this will mean a minimum of a 9channel transmitter.
In its standard form, you will require a minimum of 7 channels to operate the elevons and the canards. The channel assignment is as follows. Aileron, elevator, rudder, throttle, retracts, canard 1, and canard 2. The elevator and ailerons are mixed as elevons and the canards operate as both elevators and ailerons both being mixed with the elevons. It may seem complicated but Motion RC has a video on the website that explains exactly how to program a Spectrum transmitter and also a Futaba. The VT unit requires one left and right mixed with the rudder and the other up and down mixed with the elevons and canards. The operation of the VT unit should be on a separate switch so it can be switched on and off as you want it. You will find there are no instructions covering the installation and operation of the VT unit. This is left entirely to the pilot to set up however you feel comfortable with it. Having said that there is a video on the Motion RC website covering the setup and operation of the unit. However, you will need to adjust it to suit your style of flying.
The assembly of the model is typical Freewing and it can be assembled in about an hour and another hour or maybe a little longer if you have never flown with canards before. The quality of the finish is excellent on the model I have. It was picked off the shelf as a regular sale and shipped as normal free shipping.
With the VT unit fitted and the model finished ready to fly the battery will need to be secured as far forward as possible to obtain the correct CG position. You will also have to have the nose cone and the canopy fitted, it is that close. Without the VT unit, the CG won’t be an issue at all.
The day I chose for the test flight was really far from ideal with the wind blowing a steady 25MPH gusting to almost 30 at times. In fact, I waited for what seemed like half a day to see if the wind would reduce, but it didn’t.
With a fully charged 6s 6000mAh battery, I lined up into the wind and pushed the throttle forward. The model accelerates quickly and the take-off was not an issue even in the 25MPH wind the model flew flawlessly. It should be noted I am flying the model WITHOUT a gyro, and I had no problems with the flying characteristics at all. Reducing the power into a headwind the model will almost come to. A standstill with the nose quite high. However, you won’t be able to achieve the same flight characteristics on a calm day. I didn’t play with the VT unit on this occasion in such windy conditions.
All-round an easy to assembly, and a great flying model.
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