A blast from the past with a review of the Windrider Fox by Dave Taylor.
I first came across this Fox on the Internet as it was being advertised on a few sites. This lead me onto the Windrider site and it was from here that I purchased this model. The site which is windrider.com.hk is an interesting site as they make other kits of both glider and power planes and is worth having a good browse through. If you require further evidence of this glider then there are lots of footage of the Windrider fox flying on You Tube. One is even being flown in Dynamic soaring at a weight of 32 oz.
Specification
Wing span: | 66 inch |
Length: | 35 inch |
Airfoil: | RSB 77 |
Wing area: | 2.15 sq. ft |
Weight: | 15 oz |
Material: | EPP foam |
Radio: | 2 or 3 channel [4 with tow release] |
Servos: | 3to 5 |
C.G: | 2 inch aft of leading edge |
So a phone call to my brother and he had one ordered and on its way to me. It arrived on my doorstep in 8 days. Now that’s what I call good service and all for around £50 including p+p.


Building
So now we get onto the building or should I say assembly part. Which if you happen to have the right size servos, Y lead and extension leads handy is very quick. The instructions consist of two sheets of A4 and a large A3 exploded drawing which explains the assembly.



If you had all the extra bits to hand I reckon you could put this one together in about 2 to 3 hours from opening the box. I have made a couple of changes to mine by using a small 3.5 gram servo in the fin to control the rudder and another small servos to work the tow release.
I had it all together and ready to test fly in a couple of evenings work. It took longer to charge the batteries than assemble.
Flying

As we fly from the flat mostly there was only one way to test fly and this called for my son to do his bit and aero tow the Fox behind his Citabria. First I thought this Fox was light enough at 17 oz to hand throw little way just to see if things were set up about right.
After a throw and a short glide the Fox did not disappoint and glided quite a distance. Now happy that it went quite straight we hooked up the to tug and off we went.

As with all Foxes that we have aero towed before the first bit of the tow getting it off the ground was the hard bit. However, once in the air it handled very well. On the tow it was noticed that as the Fox transited from below the tug to take up a higher position as it went through the disturbed air from the tug the wings flexed and flapped. This was quite strange to see.
So up to height and released without any problems and proceeded to try out the stall and spinning characteristics.
At the recommended C of G position of 2″ from the leading edge it quite happily stalls then drops a wing if you are not quite into wind and spins. I could live with this but it also stalled on me when I was entering a loop so this needed to be altered by moving the C of G forward slightly.
Before I flew the Fox again I added some weight to the forward area of the radio compartment and up we went again and this time the stall was straight and any spinning was stopped quite easily. The loops were entered nicely and the elevator felt altogether more positive in pitch.
So after a few more areo tows that evening and apart from the disconcerting wing flexing I was beginning to like what I had bought and assembled.
Our next mods were to add some light weight clear tape length wise on both wings top and bottom starting from the rear and working forwards so to keep the joins flush to the airflow and this seemed to strengthen the wings better. Then my son and I discussed whether or not to add two aluminium tubes, one in each wing into which the carbon spar goes. This we did using 9/32″ k & s tubes. The result of fitting these has been to strengthen and therefore stop the flexing of the wing. Importantly it has not added much weight but if you add these aluminium tubes they do not need any glue as it is a very tight fit. However, care must be taken when fitting so that they aren’t pushed off line.
Slope Soaring

OK so the next flights were done slope soaring and we also added around 2 oz of weight under the battery. These mods worked as now there seemed to be little wing flex and flying in 10 – 15 mph wind the Windrider Fox really did fly well. The wings were not flexing and loops could be pulled quite hard or opened out nicely. Rolls were crisp and generally the Fox felt good moving up and down the slope with good speed and retaining energy well.

It was time to hand it over to my son who is rapidly becoming a good judge of what feels good in flying gliders. He gave it the thumbs up and like me cannot wait to fly it more and enjoy it’s good flying characteristics.
In conclusion
The Windrider Fox is a good all round glider. Excellent value for money, lightweight easy to pop in the back of the car. Good for aero towing and sloping. It can even stand the odd ‘bounce’ or knock with damage. Looks sleek in the air and even gives the impression of being fast when on the ground.
Comes highly recommended by us both.