Rarebear Funfighter. First Flight.

back in business...

The Rarebear was my second fast plane, after the notoriously hard to launch Radjet. Despite its diminutive caricature proportions, it was blindingly fast and flew on rails. However, as happens, it had it’s share of incidents, including a near lipo fire and a high speed excursion through a barbed wire fence. Finally, battered and weakened beyond stable flight, it was retired to the wall and gradually stripped of it’s internals for new projects.

So it was with great excitement that I came again to consider another Rarebear to join the flying corp. The first time round I’d chosen the PNF version, in the rather dull white and brown livery, but this time I got the ARF kit, unpainted and without decals. This time also I changed the battery; last time I went with the “ballistic upgrade” 45-90C which, when combined with the diminutive current-junkie funfighter motor, makes for epic speed and addictive noise. However it was far too fast in reality, so this time I chose the same 850mAh 4S battery, but in more sedate 25-50C form.

Also, I had a bit of fun rendering the Rarebear into its donor Bearcat regalia; Navy decals with pacific blue paint (a few shades lighter than the real thing). Overall I thought it looked great. Also, importantly, I applied tape to all the hinge lines (excluding the rudder which doesn’t function) to avoid a repeat of the “missing bits” episode of the original.

So to the first flight. Yes, I was nervous. The Rarebear is small, fast and can kick on launch, so certainly not to be taken lightly. So it was with some trepidation that I threw it up on about half throttle and held my breath.

As it turns out, the rare bear was very well behaved, climbing sweetly into the sky; a little steeply because I’d set the elevator up a bit and, after it had levelled off, flew absolutely beautifully, straight and stable, turning with characteristic crispness and climbing with absolute disregard for gravitational dynamics.

In all, the first flight was excellent, the little ‘bear even slowing up for landing without a hint of wing drop, so I’m now looking forward eagerly to pushing the limits towards full throttle, enjoying the subdued howl of the little fighter across the kangaroo paddocks…

FT Cruiser X-57. First Flight.

...hey I made an X-plane. sort of...

Having seen NASA's intriguing X-57 Electric Research Plane, I decided to converted Flitetest's twin-engined FT Cruiser into an RC version of NASA's experimental plane, featuring twin electric motors mounted in the wingtips.

The X-57 actually features 14 motors, twelve small motors with folding props mounted in the leading edge of the wings providing supplementary power for takeoff. The two larger motors installed in the wingtips provide the high-speed cruise propulsion.

I wasn't going to be wiring up fourteen motors, so I dispatched with the dozen leading edge units favouring the simpler hand-launch solution. I used small 89W quad motors (1806 2300kv) running at on a 3S 2200 battery. The propellors are 5x3 props, swinging inwards sweeping air onto the top of the wing to counteracting the wingtip vortex.

This is one of the main benefits of the wingtip design, a second being that the concentrated wingtip flow feeds into the propellor, increasing the dynamic thrust. Finally, additional thrust is generated by virtue of the outside sweep of the prop being unimpeded by the presence of a wing; the prop wash goes into free air.

The modified FT Cruiser with weighs 940g all up, or 749g without battery compared to the spec mass of 766g. The 17g difference is due to reduced wing size, one less servo (rudder servo ditched in favour of differential thrust) and smaller motors. However, 7g ballast had to be added to the nose for CoG correction due to the motors being set rearwards compared to the standard Cruiser configuration.

The motors generate a combined 710g of thrust as installed, sufficient for cruise but certainly not 3D flight. Static thrust of a commercial aircraft is a quarter of its loaded weight and around half of its empty weight. In the case of the xCruiser this would equate to 235g to 470g respectively. So it's comfortably powered in aircraft terms although less so in RC terms where closer to 100% is nice-to-have...

Turbo Porter Sunset

...evening walk became an evening flight

Wild rainy weather for the day suddenly subsided into a golden sunset, warm rays flooding under the dissipating sheet of clouds. Taking the opportunity for some exercise, I headed out for a walk. However I hadn't made it to the corner before I'd decided that this would actually be a great time for a sunset flight.

I don't often fly at the local fields anymore as there's not that much space, quite a few trees and often people walking dogs or playing. However, with sunset approaching and it having just stopped raining, I packed the Turbo Porter and headed down the road.

As ever sunset changes rapidly and the best of it was gone by the time the Porter headed to the skies. However, I managed to capture some of the fading sunset and enjoyed compiling the video... 

Canadair on the Duckpond

...finally flying off the pond

The field where I often fly was prone to flooding at the southern end; an event which occasioned the influx of birds of all kinds and the occasional kangaroo something for a splash.

However, unfortunately the sports club didn't share my enthusiasm at an inundated playing field and so instituted an engineered solution to pump the flood waters away. Happily, after a year or so, this fiendish system has failed, heralding a triumphant return of the ephemeral pond.

I had often been tempted to get something flying off the pond but for some reason never got around to it. However, for once, I managed to get to the field with a float plane while the pond was still full and when the weather was OK, in this case with the Canadair.

Unfortunately, as far as the video was concerned, the sun dipped away behind the clouds just as I the Canadair hit the water, so the video quality was frustratingly compromised. Despite that technical hiccup, the flying was a success, making the wait worthwhile...

Raptor Sunny Clouds

...a ray of sunshine

The weather this autumn and winter has been dreadfully windy, all the more remarkable given that this is usually the stillest time of the year and the opportunity I'd taken to fly off the lake in the still afternoons.

However, there have been a few occasions when the gusting northerly has abated and yielded bejewelled afternoons, like this one.

Heading down to my usual spot, lovely cumulus decorated the vivid blue sky, the dark grey of their undersides vividly contrasting with the sparkling white of their peaks. As on the best late-afternoons, the clear horizon allowed a full spread of lush, golden sunlight to drench the lush greenery of the fields and add a sense of magical perfection to the scene.

These are my favourite flying conditions, preferred to sunny mornings or even lovely sunrises, except for when I'm suddenly wanting to capture a special moment of exceptional light, or beautiful cloud formation, or ibis flying formation.

Fortunately, in some cases such as this, I don't need to worry as I've got the video running and I can enjoy the moment. Flying the Raptor now is lovely, my favourite being it's red and white wings contrasting vividly with the blue and greys of the sky as it sweeps past...

Phoenix 2000. First Flight.

...a little slope soaring

I've chosen to set up the Phoenix 2000 as a pure soaring glider without motor, running a 2200 3S battery located right at the firewall and some small-change ballast installed in the nose cone.

I have configured the Phoenix with crow brakes, as I discovered that having some sort of brake/lift dump is essential, whether that be fence-type brakes or, in this case, flaps and ailerons configured to generate drag and reflex the airfoil respectively

There are, unfortunately, no good slope soaring sites nearby, however I decided to try the hill at the far end of the paddocks where I fly; not particularly high or steep but enough to generate a little lift.

The wind was a strong north-wester, a little gusty too, and I launched the Phoenix with as lusty a hurl as I could summons. The Phoenix flies well enough, catching what little and sporadic lift was available here.

I tried the Phoenix with and without flaperons active but, given the very turbulent conditions, I couldn't asses the effect they have.  Similarly, I didn't get the opportunity to really test the crow brakes, however they were effective in slowing the glider down and didn't cause it to climb when deployed which is good.

However, as a first try, the Phoenix is encouraging, so I'll be trying to get it flying in some better lift... 

Fox Glider with Funfighter Motor.

...back with avengeance

The little Fox glider is a beautiful flier, however mine has always suffered from motor vibration. Even the addition of a supplementary firewall didn't make much difference, so the little Fox was eventually consigned to hang on the wall whilst I decided what to do.

Help came in the form of the forced retirement of the Radjet, and I transplanted the Funfighter motor I'd installed there into the Fox. To complement this I'm using a 1500 4S Zippy compact battery, lightweight enough not to tax the speedy motor but large enough to provide generous flight times for the sleek Fox.

The result is speedy, the slippery Fox now genuinely fast and very quiet, the Funfighter motor providing it with landscape-traversing speed and generous, although not unlimited, vertical climb.

So all in all a simple and very successful transplant, the Fox glider flying with the Radjet's heart...