Flitetest X-57. Take 2.

...a long time between drinks

After a long hiatus the X-57 is back in the air and flying OK.

The issue I'd had initially with unbalanced thrust turned out to be only an over-tightened motor mount - backing off a couple of screws was all it took to get the slow motor spinning up to speed.

However, the wings still seem to be generating too much lift, with the X-57 soaring with even modest throttle settings and fairly wanting to loop with anything more than that.

In fact, I had to fly it with negative elevator trim just to try and get it flying level-ish. For my next try I'll use a heavier 4S 3000 to try and even things out a bit.

This may help it fly level and so help to eliminate the problem of the big disparity between power on and power off flight and allow it to glide properly with a bit of airspeed. At the moment when you cut the throttle it stalls which makes trying to land it, well trying...

FT 3D. First Flight.

...got there in the end

As soon as I saw the video of the FT 3D I decided I was going to have to make one. The build was reasonably simple and the product looked great; a pert-looking aircraft with blacked-out canopy and bristling with vortex generators and wingtip plates.

So it was with much anticipation, and nervousness as usual, that I got around to its maiden flight. My first mistake was the rates weren’t turned down enough, and the expo needed to be much higher. I was lucky to recover control before it speared into the meadow and brought it round to land so I could reprogram the Taranis.

Second mistake is it didn’t really glide - I cut power expecting to ease it in for a landing, but instead it stalled and plummeted down, buckling the undercarriage and breaking the motor mount.

Taking it home for a re-think, I installed a smaller prop than the very solid unit which was one of my Trainstar spares and also cut off the back half of the swappable power tray which was doing nothing. Importantly, I also covered the underside of the cowling with poster board in the hope the shape would support the nose which had been dropping severely on the first flight.

So, back to the field again to test the results, which happily showed significant improvement. Except, unfortunately, that this revealed another problem - the ESC overheated despite the NACA duct cut right in front of it, causing the FT 3D to once again plummet down for a repeat end to the flight.

Take 3, now with a NACA scoop - an inverted NACA duct service as a very large scoop to keep the ESC’s delicate constitution cool. And this time everything seemed to work - the #D was light & floaty enough, easier to control and seemed happy to be flying. All good, now time to learn how to fly 3D properly…

Stinger 64 EDF. Repair Flight.

...back in the air!

It was months ago when, having too much fun with the Stinger, I inadvertently sent it speeding into the swampy paddock grass, where it half its nose and my near-new nanotech battery disappeared into the mud.

Since then I have agonised over how I was to replicate the tapering form of the nose, which also accommodates the canopy magnet and terminates into the join with the nosecone.

Eventually I used rear sections of the original fuselage (funny how you never crash backwards), although this wasn't quite right and had to be cut, and then added onto, and then filled, and sanded, and painted.

However, after this unnecessarily protracted affair, the Stinger was again airworthy and looking pretty good. However, the proof of the pudding if in how well it flies.

Fortunately, in this case, it flew as well as ever, and I was gifted with a good launch as well. So back to enjoying a few run-filled, adrenalin rushing minutes screeching the Stinger around the paddocks...

Trainstar Tough Trainer 1400 EPO. D4023 Motor Test Flight.

...test flying the new motor

Fortune smiled this afternoon with the growing cloud cover holding up just enough for a scenically sunny afternoon for flying. Conditions were a little choppy but, given the lovely afternoon, we were going to give it a try anyway.

As well as being the test flight with its new motor, this was also the first time I’d flown the Trainstar for months after its collision with a light pole, so it was perhaps not surprising that it was out of trim.

As soon as it took off, it was evident that the Trainstar had become very floaty, in contrast to the nose-down attitude I’d been flying it previously. Nevertheless, it was still fun to have it back in the air.

After having a bit of fun floating it around, I brought it in to check trims, and then it was back in the air, flying a bit flatter than before. It was still not smooth flying though, with gusty conditions and wind shear above tree level turning the Trainstar into a kite of sorts.

The new motor performed very well, at least as powerful as the OE unit, and perhaps a little more. Considering its modest cost and ease of replacement, it’s a viable alternative to Volantex’s dodgy prop adapter…

Stinger Ready to Go

...hopefully it will be good

The Stinger has been reconstructed with its new fuselage and replacement fan unit, fitted with a zen-first R615X receiver  and, just yesterday, received its new Nanotech 2200 4S 45-90 power pack.

Apart from it looking sharp and new with the replacement fuselage, and interest in how the new DSMX receiver will work, it's the performance impact that the big nanotech will make that I'm most intrigued in.



And it is big; in fact it's too wide to fit easily into the fuselage, bulging the foam past the matching form of the canopy. I'm hoping that in due course the foam will compress a little to reduce this distortion but there's no denying that there's a lot of battery there.

My experience with 4S nano's on my Rarebear indicate that they offer substantial performance improvements, although I'm not sure whether, in this case, the additional grunt will be offset by the increase in mass over the 1800 40C Zippy I used previously.

Anyhow, I'm very interested to try out the reborn Stinger. I had, in fact, been hoping to get it out this afternoon for a test run but the weather wasn't cooperating with overcast and windy weather. Lets hope there's a mild and sunny afternoon in the offing soon...

Radjet Test Flight Havoc

...but got there eventually

I took the Radjet to the field today for a test flight in its new sleek guise, a beautiful sunny afternoon with clear blue skies and a refreshing southerly breeze.

As well as the new nose, I had reset the Radjet's controls and checked servo throws as well as reducing the elevator trim I usually have as I reckoned the Airbus-like fuselage interface would generate lift in flight.

The first launch was a complete crash, with the Radjet nosing down as of old straight into the ground. I figured this was because of the lack of elevator trim, so dialled it back in again. The second attempt started well, with the Radjet climbing steeply into the sky as I craned my neck to keep track of it.

However, as I levelled the Radjet it suddenly went unstable and ended in a flat spin, the only thing I could do was put full aileron and full elevator which slows the descent of the plane still inescapably spinning.

Collecting the Radjet I reckoned I knew the cause; the plane was balancing on the fingertips but only in the centre of the grips; slide the fingers forward and the Radjet was tilting back. I had hoped this would be OK but proved this wasn't the case.

A solution to this was to re-orientate the receiver so that I could push it further forward in the nose, and shoved in a small stick, the only ballast I could find at hand. So, with the plane now balanced I went back for the third try.

Fortunately this time everything went to plan and the Radjet went careering into the sky. My guess about the new configuration generating lift was right, so I had to dial the elevator trim back to neutral. This levelled the flight, but means I'll have to figure out something for launch next time.

The Radjet seemed faster, and twitchier, the former certainly due to the sleek nose, while the latter I think is related and I've just increased the expo a few percent. So, the Radjet is back in the air at least, although not without some drama, and I'll have to do a little work figuring out the launch next time...

Radjet Test Flight with 4S 1800 Battery

...without disaster or mishap

This afternoon was gorgeous and sunny, slightly warm with a gentle breeze from the south west, perfect for letting the recently-refurbished Radjet loose with its boisterous battery pack, the 1800 4S 40C borrowed from the Stinger.

As mentioned previously, I'd had several concerns relating it being too heavy with the oversize battery or simply bursting into flames due to the ESC being overworked. Fortunately, neither happened, with the Radjet taking to the skies without incident and flying well.

I did a few circuits before bringing it down, needing to make a few adjustment to the elevator settings after the servo change, and also to dial in a little more expo with the new servos having a bit more travel than before. Having sorted out the details, I threw the Radjet up again to give it another run.

The battery, significantly larger than the recommended 1300 and substantially larger than the 850 I'd been using, is rather oversized for the power system and changes the characteristics of the Radjet into something of a grand tourer. I think a 1300 4S battery is probably the ticket, providing enough current and flight-time without carrying any excess.

So, while this exercise answered one nagging question, it also raised another; considering it can comfortably carry the 1800, what if you uprated the motor and the ESC...

Canadair on the Water

...just weeding out problems

Yesterday was the first opportunity to get the Canadair 415 onto the water but unfortunately things didn't go well, to the degree that the Canadair didn't even come close to getting into the air, which was rather unfortunate as it was a spectacular afternoon for flying.

The first issue was the rudder, which proved almost immediately to be bordering on useless. It appears the thin wire mechanism, incorporated into the tail assembly, is much too lightweight for the job, so the Canadair ended up drifting rather aimlessly around the lake and ending up having to power it through the water weeds as steering it back wasn't an option.

Fortunately, as we know, the Canadair has a surfeit of power which saved it from the indignity of being marooned on the water. This was all the more impressive when one saw the amount of marine foliage that the fixed rudder had gathered as the plane trawled through the weeds.

The second issue was that one wing was heavier than the other so that, despite the plane accelerating on the water, I was unable to get the wings levelled. As a corollary, with the float stuck on the water, the Canadair was progressing in slow circles.

I eventually gave up and ploughed it back to shore. The wing balance is a relatively easy fix, however the rudder function is a more taxing issue altogether, and something I'll have to do some research on...

Turnigy Thrust Test

...the Canadair's cooking

Following my concerns regarding the Canadair 415's prop size, or lack thereof, I conducted a rudimentary thrust test using a scale. First up, the Canadair weighed in at 1.25kg all up including a 2200mAh battery.

The Canadair sounded quite impressive running up to full power, with the scales indicating it was developing somewhere in the region of 1.6kg thrust, close to the quoted maximum of the Turnigy L2210's and more than adequate for getting the water bomber into the air...

Floatplanophobic

...need to gather the nerves

I returned today to the lake, ostensibly for the second attempt to take flight, but found myself so uncomfortably nervous that I ended up refraining from any attempt, despite the immaculately calm cool and sunny conditions.

I haven't abandoned hope of flying the floating Trainstar, rather that I didn't want to risk flying it when very much not in the zone. As I'm sure I've said before elsewhere, flying when you're not all there is an invitation for disaster, something I've proven repeatedly.

However, there is a fine balance between tenacity and dogged stupidity. The problem is you don't know where the line is until it's been crossed, with evidence posthumously clarifying with hindsight. However, there is a very familiar feel to this chapter, learning to fly all over again, very much like with the Floater Jet; I don't know why the takeoff run is all over the place, yet I don't want to give up. But I'm also wary of carrying on regardless and ending up with a capsized plane.

On the plus side, however, is the fact that the floats are oversized, have been positionally optimised and have proven to be a very stable setup. Also, the Trainstar has actually taken flight, and landed basically by itself, needing nothing more than a straight-ish run and a nudge on the elevator.

So, what's all the panic about? Well, I don't have the takeoff run under control, as I mentioned. And I wasn't even sure it'd fly, although that has been demonstrated, even if only briefly. And, if things really go pear-shaped, I have a rescue boat at hand, which would actually be fun to try out even if the motivation for the outing may be less so.

So, in reflection, all I need to do is put the Trainstar on the water and get it running reasonably straight.

Really not a huge drama...

Trainstar Floatplane Flight Trial

...disappointing but not disastrous

Today was the day I'd been anticipating for a while; the Trainstar floatplane had been adjusted and fettled following from its initial water test, I'd decided on a flight test venue which provided acres of open water and the weather was immaculately calm after weeks of windy weather.

Despite the anticipation, or perhaps because of it, I was anxious rather than excited at the prospect of finally getting the seaplane into the air. Nevertheless, with golden opportunities like this afternoon hard to come by, especially lately, I wasn't about to postpone proceedings due to indeterminate uncertainty.

Arriving at the lake the conditions were absolutely ideal, a far cry from the windswept expanse of water I'd experienced on my reconnoitre here. The Trainstar was unpacked and installed on the lake without much ceremony or excitement, nerves serving to rather deplete the joy from the occasion, despite the fact that the Trainstar cuts a most appealing figure in floatplane configuration. 

The first few runs didn't offer much encouragement, with the Trainstar suffering from the same take-off skittishness it exhibits in wheeled form. Not having been too fussed with ceremony, I've always just worked around this characteristic of the Trainstar, after having abandoned my efforts to get it taking off straight; flying off a field means no runways to follow. Unfortunately the flipside is now that the Trainstar is much heavier, being able to haul it off at an indecent angle is no longer possible.

In fact the Trainstar is only just sufficiently powered; the "oversized" battery at full power now seems decidedly moderate with the extra baggage and drag. Having said that I did once manage to get the Trainstar into the air, however it was heading for the dam wall and, being too low to start turning, I just cut the power and let it land.

This, in itself, was an enlightening experience, with the Trainstar actually bouncing on it's floats several times before settling down. The landing was rather unsupervised; I really hadn't planned it much, but I was rather expecting it just to splosh straight down onto the water.

In another more alarming incident the Trainstar, approaching planing speed, actually dipped a wing and prop into the water but then managed to right itself, in a testament to the stability of the floats. However I wasn't able to get the plane airborne again, which was disappointing.

However, having had the experience and having some video to review, I'm hoping that i'll be able to return for another, more enlightened, attempt to get the floatplane flying...

Trainstar Seaplane Water Test

...and still floating at the end

This morning I did my first on-water test of my Trainstar fitted with 0.40 size floats, conducted at the local duck pond and home of the local model boat club.

I had no intentions of getting the Trainstar into the air here, simply because there are too many tree surrounding the pond, combined with the fact that I'm not sure how well the Trainstar will fly with carrying additional 300g of floats.

The floats will provide a little lift, given their curved shape at the front, however there will be a lot of drag, so the slow Trainstar will become very slow. I am going to increase the flap angle, and I'm also thinking of dropping the ailerons by half a turn of the clevis to make the wings higher-lift as an initial precaution.

The other concern regarding the flying capability is the need for a long pond or lake; while the local duck pond was fine for this first test (although I even managed to overshoot once into the bushes), I'd like somewhere to land straight ahead as part of the flight evaluation. It would also give the choice to opt out it things didn't look good, without having to go round when you might not make it.

Anyway, the water test went well with the Trainstar happily buzzing around the pond. The water rudder worked well with just the single cable operating it off the rudder control horn, and on a couple of occasions I got the Trainstar to the point of lift-off, which was encouraging. It is a little tricky to keep it on a straight take-off run, something I've experienced with it on wheels as well.

Anyway, now just to find a larger venue to get the Trainstar into the air...

Floater Jet Propellor

...a real pusher prop

The Floater Jet has been out of action for a long time due to minor wing damage, elevator pushrods needing replacement, motor removed and being short of prop adapter.

Finally, all the pieces were in place, literally, with the last piece of the jigsaw, a three-bladed pusher prop. What's special about this prop is that it's actually designed for pushers; if you've ever had one you'll know they're very noisy using standard propellors. I'm not sure why, but I can tell you that's the case.

The pusher prop is a 6x4 which fits the Floater well, and being a three-blade looks pretty cool as well. The one catch is it's spins anti-clockwise, i.e. in the opposite direction to most propellors. However this is easy enough to fix, as you just need to swap two connectors on your ESC. 

So this afternoon, as soon as I'd finished refurbishing the Floater, I headed out to the field to give it a test flight. Having been a while since I'd flown it, and with it having the different-style propellor, I was a little nervous. However, my concerns soon vanished as the Floater climbed into the sky.

The prop is quiet, in fact remarkably so, spinning with just a bit of a whine, and certainly nothing like the droning buzz it makes with the regular prop. It's even pretty quiet on full throttle and producing plenty of thrust as evidenced by the rate at which the Floater climbed.

The flight was actually most enjoyable with the quiet performance, improved elevator response and gorgeous backdrop of dramatically illuminated evening clouds.

A good test flight all round...

Grey Day

...but a relaxed mornings flying

This morning was most enjoyable, not because the morning was spectacular or because the flying was particularly good, but rather because it was just lovely being there.

It was a heavily overcast morning with dull smudged clouds covering the southern skies, but a hint of blue to the north brighten things a little.

The field was scattered with birds; a flock of black ibis dozens of small parrots feeding off the grass. A few kangaroos were also grazing on the banks adjacent to the fence.

I had the Phoenix, recently put together after it flew into a tree, out for a test flight which proved particularly challenging with it initially suffering from a heavy left turn, necessitating an emergency landing to get it realigned. Then the prop pulled off while climbing during the second flight, but was fortunately easily recovered as it jettisoned over the field.

The Rarebear also had an outing; my main aim to try and get a better feel for it's flying as I end up doing big circuits as I don't want to turn too quickly for fear it will nose-in. Visibility on dull mornings doesn't help either, making the little pocket-rocket difficult to follow...

All Lit Up

...waiting for a calm evening

Anticipating the successful restoration of the Floater Jet I'd splashed out and purchased a Lumifly LED system, comprising a controller, manual switch and four half-metre white LED strips. I also got a small 1000mAh 2S battery, one which has with the small red connector whose official designation I don't know but it's not the regular yellow XT connector.

Packaging these additional components into the Floater's nose was a challenge to say the least, and also raised a concern about it becoming excessively nose-heavy with all the extra gear packed up-front.

First of all, to clear some space and transfer a little weight backward, I pushed the receiver right back into the rear of the fuselage where the ESC resides. To ensure no loss of signal will all the gear on board I made a hole in the side of the fuselage and taped the antenna to the outside. I didn't bother with a satellite receiver as I'm not planning to let the Floater stray too far from base these days...

With limited space between the battery and servos, I opted to lay the extra battery flat on top of the main unit and placed the LED controller on top of this held in place by velcro tabs. I also pushed the whole lot as far rearward as possible for better weight distribution. The LED strips, which are not the self-adhesive kind, I taped onto the wing and fuselage with clear tape placed in between the LED's themselves. 

The result is quite spectacular when viewed in low light, with each strip having five high-intensity LED's shining a clear white light. The kit comes with four strips as standard but I'll be adding another pair to the underside of the wings for better visibility from below.

With all this gear on board I was understandably a little nervous regarding how the Floater would respond, particularly on launch with its unfortunate predisposition for nose-diving into the ground. Well, having tried a few launches with success, I can happily say it manages the extra weight with little apparent effect. One does still require care not to launch with excess power and to be ready with the elevator as it noses down on launch, but otherwise it flies pretty much as well as ever.

The characteristic porpoise effect is still there as a result of the large disparity between powered and unpowered flight regimes. However it's at its happiest when gliding, its large wing area allowing it to float peacefully and silently as if magically transformed into some sort of ethereal whisp...

First Flight with 2200mAh Battery

...and the carbon prop

The weather this morning had calmed sufficiently to venture out with the Walrus for a flight. Not just any flight, the first flight with the 2200mAh battery installed in the nose.

The Walrus assembly instructions do not provide any particular clues regarding location of the battery. In an attempt to resolve the packaging issues, I had fabricated a battery tray directly behind the motor. This layout is similar to the Phoenix 2000 and worked well with the 1800mAh battery I'd been using.

Lifting the Walrus out of the car I could really feel the extra thirty grams of the larger battery, located well in front of the wings. However I held my resolve not to change-out the new battery for the smaller unit sitting in the car, and headed out. There was a moderate breeze blowing which would help the Walrus to get flying quicker, which was good.

All connected, I set the throttle generously and heaved the Walrus up. I was prepared for various scenarios, being prepared to hit the flaps if necessary to get a bit of emergency height, and perhaps having to nurse the gravid Walrus onto a high-power approach to prevent it from nose-diving.

My concerns, however, proved groundless as the Walrus soared into the air without a hint of imbalance or labouring under the heavier load. If anything, the heavier battery gives the plane a more planted feel in the air, and the higher output combined with the larger carbon prop transform the Walrus from an intermediate trainer to a sports tourer. It's performance is now much more three-dimensional capable of higher speeds and sustaining steep climbs.

With the good news of power and speed one would expect a nasty compromise on approach. However I am relieved to report that the Walrus floated into the breeze for landing absolutely happily, for a landing as easy as any...