Canadair 415 Float Mod

...the last piece of the puzzle

The Canadair 415 has been somewhat of a trying exercise; first the several hurdles in getting it built and then the issues on the water, namely non-functional rudder, researching proportional thrust and then, finally, figuring out how to launch it without the wing floats diving into the lake.

The solution for the latter was, fortunately, quite simple, requiring just a few millimetres (I took off five) trimmed off the front of the float-mount to increase the angle of incidence of the float. I'd actually considered doing this up-front but had decided to try it out unmodified.

The default configuration may work, but only in mill-pond conditions in my opinion, as the scale-float cannot manage even the most modest ripples ,which simply wash over the float and causing it to immediately submarine.

As I said, I randomly chose a 5mm trim which has worked fine, although I have seen videos where the floats have been tilted significantly more than that. I think it's a matter of "horses-for-courses", however I think that some increase in incidence is required to avoid frustration...

Canadair Takeoff Technique

...a few issues to address

I decided to get the Canadair as a companion for the Trainstar floatplane, a well-recommended twin-engined flying boat, high-powered unlike the marginally-powered Trainstar in floatplane guise, which should be easy to launch and relaxing to fly.

Well, after several visits to the lake I can attest to the former not being the case, certainly for the uninitiated, and that I have therefore, unfortunately, not been in a position to enjoy the latter.

There are a few tricks, it seems, that one needs to know. I haven't yet been able to test or master these, however I have an inkling on what needs to be done to get this boat flying.

Wing Floats
Problem - the wings floats leave a gap to the water and, therefore, the wings are initially tipped to one side. Unfortunately getting the wings level involves a conundrum; the ailerons are ineffective at low speeds and, if you attempt to speed up to remedy this, the wing floats end up submarining and causing the Canadair to execute a handbrake turn. 
Solution - trim a 5mm wedge off the wing float mounts to increase the angle of incidence of the float. This makes the float less likely to plough under the water during takeoff.

Take-off Run
Problem - as above, so many of the successful launches I've seen are executed with a very short takeoff run. Those that have a longer run are either done in absolutely calm water conditions or are marginal/unsuccessful.
Solution - get the Canadair moving and then quickly increase the power. The effect of this is to cause sudden downforce on the elevator before the Canadair speeds up much, effectively pushing the back into the water and getting it onto the plane almost immediately. Additionally this same effect means the front of the wing floats is rotated up by the same effect, supplementing the incidence modification as described above.

I think there is a knack to the latter solution; I have managed to get it planing in this manner but have aborted the launch due to concerns of the wing floats digging in and causing a crash (splash). I am hopeful, however, that with the wing float modification and a bit of practice, that my next attempt will be more successful...

Trainstar Floatplane Sorted

...finally enjoying the moment

Yesterday afternoon I headed off to the lake again with the Trainstar, hoping that finally all the work I'd put into sorting it out would pay dividends and I'd be able to have an enjoyable afternoon punting it around the lake.

As it turned out the flights were really good; nice smooth takeoffs, peaceful and uneventful flights finished off with reasonably good landings. Using full elevator for landings this time, I managed to keep the Trainstar on its floats every time although it was still dropping too fast. The last tweak I need to do then, is to take off the flap mix I've been flying with.

This is good on the gliders when flying slowly however, with the Trainstar having to fly on about three-quarter throttle, the tail doesn't need any lifting. So, by switching the mixing off, it will give me a little extra elevator travel, just what I need to be able to level the Trainstar out on landing, hopefully enough to eliminate the bouncing which has been a characteristic of every landing it's made so far.

Changing the elevator setting will hopefully also give teh Trainstar teh ability to climb a bit better, as at the moment it flies pretty flat, which can be a slight concern given the number of trees lining the lake's edge.

The good landings were, of course, a great assistance ino keeping the servos dry...

Waterproofing Servos

...silicone sealer and dielectric grease

Having thought the Trainstar floatplane was completely sorted, I've discovered that the wing servos, in particular the aileron servos with their exposed extension join, are prone to water ingress.

Due to the smallest waterproof servo available being much too large to fit into the wing, it was necessary to waterproof the existing servos and connectors. I had intended to use dielectric grease however I was concerned about contamination affecting the covering tape over the servo wires and so opted instead to just go with silicone sealer.



I sealed the cable entry to the servo housing, which seems like the most likely water entry point, and sealed the servo connector and the extension harness. The joins in the servo housing didn't seem like a problem, and I haven't sealed around the pinion gear due to access problems on the already-installed servos.

This is the one area that would require the grease, however I was wondering whether a haphazard application of grease might be worse than none at all, considering that the area most accessible would be on the underside, possibly trapping any splashed water. So I think I'll just try the Trainstar as is and see how it goes...

Floatplane Landings

...don't try too hard

Conditions today were idyllic, a beautiful warm afternoon with a light easterly blowing, and the lake deserted as usual except for a flock of moorhens and the odd duck.

With the Trainstar now fully sorted, I was looking forward to a leisurely afternoon flying the floatplane around and enjoying the gorgeous weather.

With the rudder servo keeping things straight on launch I could concentrate on managing the liftoffs; this takes a little doing as one needs to ease off the up-elevator required during the takeoff run, however the liftoff is quite sudden and tricky to anticipate. Anyhow, the launches were a little better but still need some work.

The landings, however, were atrocious, with the first attempt off an awkward approach being all over the place and ending with the Trainstar nosing into the lake. Fortunately it was close to the shore and the breeze assisted in bringing it back without the need to haul out the dinghy.

The flights were otherwise very pleasant, with the 2700mAh battery giving good power on launch and surprising endurance in flight. The controls are still a bit sensitive, and with the weight of the floats the Trainstar is quite sensitive, however I think I just need to dial up teh expo a bit to calm things down.

My last landing, by default, was off a nice long approach after my initial botched effort, and I greased the floats in on what I thought to be my best landing so far, when suddenly the float dug in and the Trainstar was suddenly nose-down in the lake, again.

I have made lots of bad landings, but never has the the Trainstar actually gone in. I think I was trying to get it too smooth and was lacking up-elevator to keep things on an even keel...

Float Rudder Servo

...more than a nice-to-have

Subsequent to the issues I'd experienced with the cable-operated water rudder on my Trainstar seaplane, I have retrofitted the float with a direct-acting rudder servo. I chose a 40g gram servo, rather oversized but the smallest waterproof servo that was available. I mounted this directly to the float in a cutout I made, the simplest and easiest method.

Today I had the first opportunity of trying this out at the resident lake, and the result was  nothing short of a remarkable improvement. The Trainstar, which previously zigzagged around the lake at will, now tracked remarkably straight and true, the oversized servo making sure that the rudder didn't deviate a millimetre, a far cry from the now-evident lack of control with the cable system rigged off the plane's rudder.

I had originally thought a servo-operated system would be preferable, but hadn't wanted to cut into the floats. Now, having experienced the amazing improvement in stability and likely improved reliability, I would suggest a float-mounted rudder servo to be an absolute necessity...

The Problem with Seaplanes

...try and try again

My efforts at converting to water planes has been rather fraught and, in many ways, echoes the tribulations I experienced when starting flying radio control.

Firstly trying to find suitable venues has been a challenge in itself; too many people, too close to houses, too far to walk from the car or locations only occasionally accessible. And, with the Trainstar needing a fair bit of headway to get airborne, the size of the lake needs to be quite generous.

The Trainstar seaplane is also not the easiest to take off or fly, in large due to the oversize floats making it marginally powered. Additionally, the Trainstar is skittish on launch which, when combined with its gravid nature as a seaplane, make getting it airborne a bit of a hit and miss affair.

Additionally, I've discovered that the cause of the Trainstar stalling and consequently nose-diving into the lake were due to the cable for water rudder sticking, providing no rudder input during left turns. I am in the process of resolving this by adding a waterproof servo directly onto the float, a much better system but which I hadn't adopted initially to avoid having to cut into the floats.

Incidentally, the ESC didn't survive it's inebriation, becoming smoking hot to the extent it unsoldered one of the motor leads. This did, however, provided an opportunity to utilise a spare 35A ESC I've had sitting on my spares shelf for ages...

Dam Lakes

...somewhere for the Trainstar to call home

My efforts at getting the Trainstar floatplane in the air again have been unsuccessful, in part due to the weather, as in the case of today, in part due to misinformation, like yesterday, and partially because I want a completed deserted venue as I'm rather shy when I'm learning.

Yesterday I visit a great potential site, however it's bordered by houses but, mainly, had several fisherman whom I'm sure wouldn't be impressed with a buzzy floatplane invading their tranquility. However, on the way home I passed the lake where I'd first flown the Trainstar and was surprised to find the gates open, it being advertised as open only a few days a week.

I'm now hopeful that this is the case on most days, so will be taking the Trainstar along in the hope that I will be able to fly it more regularly and with less complication than thus far.

In the Interim

while the weather is wild...

The extreme tranquility of last week has, unfortunately, been replaced by gusty winds forecast to last for the rest of the week. As such, I haven't ventured out to fly anything, least of all the floatplane.

The larger batteries for the latter are on there way, and I'm looking forward to familiarising myself with the Trainstar floatplane characteristics a bit better. The new batteries should provide significantly longer flight times, but I also think that a more considered flying regime will help keep the chubby floater in the air for longer as well.

Finally in the process of reconstruction, now that I've received the replacement ducted fan, adhesive accelerator and the urge to do it, the Stinger is resuming shape. The pace of the reconstruction is slow as I'm making sure that each rip and crack is properly bonded before proceeding to the next, but also the warnings on the accelerator pack have me evacuating the room after each burst of strawberry-scented aerosol.

The foam should go back into shape reasonably well, and I think I'll smooth out the joins with a bit of filler. The only question marks are against the motor and the servos as to whether those survived the massive impact unscathed. Anyhow, we'll know that when the body has been restored and I get the electrics connected up again...

Canadair 415

...a friend for the Trainstar

Having finally been able to get the Trainstar floatplane launched and flying, even if somewhat crudely, I've been considering getting another water plane for a bit of variety when venturing out to the lakes or dams.

One plane that caught my eye was the Canadair 415 water bomber and, having read a few of the reviews, it comes well recommended and seems easy enough to launch and fly, unlike the Trainstar which is a bit more on the tricky side of things!

One thing I wasn't all that keen on is that the Canadair is only available in ARF form, requiring one to source components. Mainly this is fine, although the motor is my main concern, especially the mounting for both the motor itself and the prop. Anyway, I've followed the description and hope things will work out well, along with a couple of the 25A Plush ESC's which seem to be good.

I'll be running it off the 2200mAh's which I've been using on the Trainstar, and from what I've read that should be quite adequate. The Trainstar, on the other hand, will be upgraded to 2700mAh's to give extended flight time as a result of it's power-hungry nature from its oversized floats.

So, in a week or two we should have a bit more news of what it looks like and how the Canadair goes together...

Trainstar Floatplane Thoughts

...after the first flight

Finally getting the Trainstar floatplane into the air was quite something; I was uncertain whether the additional weight and drag would render the Trainstar waterbound and, if it did fly, how well or indeed, whether it would be manageable at all.

The first, very brief, flirtation with the sky did at at least confirm that it could fly, and that it actually even floated on the air quite well, giving me a little confidence so that, when I returned a few days later intent on getting it flying, that I could anticipate at least some success.

The Trainstar flew unexpectedly well, I suppose given that I hadn't expected that it would fly at all and, that it manages to maintain a turn at all, with the weight of the floats, is quite remarkable. However, in this case, I think the water rudder plays a part in keeping the floats up in the turn, meaning that you need to keep the rudder on or the self-centering effect very quickly brings things on an even keel.

The generous proportions of the floats makes the Trainstar virtually unsinkable, righting the plane even when it has tipped over with the prop flicking the water and when the wingtip has been on the water at speed during an attempted launch.

The flip-side, however, is that the Trainstar is very slow, and turning into the wind on approach turns moderate pace into pedestrian approach. I've only flown it with the flaps down, in addition to the slight down attitude I dialled into the ailerons, meaning the the Trainstar is flying in a very high-lift configuration. As such it becomes very floaty when the power is off.

I'm interested to fly it without flaps to see whether the reduced drag improves it's flight. Also, it seems the floats contribute to lift up front, which helps to keep the nose up. However I think the consequent drag also tips the nose down under power.

Lastly, another apparent effect of the additional mass and drag is that the flight times are reduced significantly. I'm looking at a slightly larger battery, which is also only slightly heavier, to improve this. However I think that with a better appreciation of how it flies, that I may be able to improve on this and reduce the amount of full throttle flight required...

Trainstar Floatplane First Flight

...it flies!!!

Opting to go with tenacity, due in part to today being the last very calm day forecast, this afternoon I headed off to the lake again with the Trainstar. The lake was not the location of first flight test, but rather another smaller venue promising virtually no onlookers, a feature which I found highly desirable.

There was a slight breeze blowing, not enough to unsettle the surface of the lake but sufficient to lend some assistance to the Trainstar to get airborne. The wind was also a northerly, helpful as access to the lake is at the southerly end.

The Trainstar was soon unpacked and on the lake, all tested and ready to go. I can't exactly remember the sequence of events, this first session also not being video'd for fear of tempting fate. Nevertheless, after a few false starts, I had the Trainstar in the air and flying.

Having had a brief airborne episode before I knew it would fly, although not exactly how, so the first takeoff was very much a beginner effort, with the Trainstar being hauled up, the climb angle eased off and then immediately increased as the plane started to drop, not being at all sure how it would behave.

The turns also took some getting used to, the weight of the floats dramatically increasing the self-righting effect the Trainstar has thanks to its wing dihedral. Nevertheless, the Trainstar still climbed and turned surprisingly well, and I cruised it overhead before turning back over the lake.

As I mentioned before, it becomes very floating with power off, I think due to the increased flap setting I'm using, although I'd expected the opposite with the float drag. However, having said that, I did expect the boat-shape of the floats to contribute some lift so perhaps that effect is more than anticipated.

At any rate the Trainstar floatplane is very predictable of landing approach once the speed has dropped off from cruise, although I still only managed one landing which was good, the others being a decaying series of slapping jumps off the lake. However, due in no small part to the generous nature of the floats, the plane never once ended in the drink, the buoyancy and stability of the floats righting and steadying the Trainstar every time, even once when I had the wingtip on the water with power still on full.

The only problem I had was running out of battery one one last approach, the Trainstar landing in the middle of the lake, having to resort to occasional brief bursts on reserve power and the breeze to return the plane to the shore...

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...

Float Plane Adjustment

...fine tuning the floats

Having done a water test with the Trainstar floatplane I've been researching techniques on launching floatplanes. In the process I came across more detailed sketches of floatplane configuration which caused some concern regarding how I'd installed the floats.

While I'd got the basic setup correct, with CoG in front of the step and the front of the floats ahead of the spinner, the proportions weren't right, with the CoG being too far ahead of the step (around 45mm) when it should be about 10mm, and the tip of the floats was about 25mm ahead of the spinner when ideally it should be greater than this.

The setup and installation of the floats is quite fiddly and awkward so I wasn't really keen to repeat the experience, and additionally moving the floats would mean a set of open holes in the floats which wasn't desirable.

However the rationale behind the setup criteria were quite compelling; having the CoG too far ahead of the step means rotation during takeoff is harder, and having the floats extending further forward reduces the risk of the plane capsizing which, despite having invested in a rescue craft, is a highly desirable feature. Finally, and perhaps the deciding reason, was that the Trainstar's CoG was in fact a little far back, which would be corrected by moving the floats forward without needing ballast, something I absolutely don't want to do.

So I bit the bullet and uninstalled the floats. I'm still in the process of attaching them about 30mm forward, however this position has adjusted the CoG perfectly in terms of the step and the floatplane as a whole.

So, I just need to finish off the screws and the seal around the mounts, and do a bit of sealing of the unused holes and a cosmetic touch-up. The weather has been terrible lately, so I might just pop down to the local pond again and do another water test, this time perhaps trying to get the Trainstar planing more and, perhaps, even airborne for a few feet to give myself a bit more confidence...

Seaplane Risks

...clearly requires more consideration

Having successfully completed an on-water test of my Trainstar floatplane, I've been searching for suitable large expanses of water for it its first flight. Suitably large is a requirement as, with an additional 300g of mass, I'm not sure how well the Trainstar will fly.

I've found a couple of potentials, a dam and a lake, however standing on the shore and picturing the Trainstar scooting across the water one is struck immediately by a quandary; what if something should go wrong? While a large expanse of water mean no obstacles to avoid, it also means a swim if anything goes wrong.

Although I think the risk of a tip-over is small, the consequence is a rather unpleasant swim in cold lake. This sort of consideration isn't immediately apparent while enjoying watching videos of seaplanes happily taking off and landing. The local boat club has a dinghy for retrieval of boats in these circumstances, although this isn't something I have access to.

My ideal venue for flying the Trainstar has therefore been revised to a large expanse of water no more than a foot deep. I'll let you know when I find it...

Seaplane Floats. Unofficial Unboxing.

...very cool

The seaplane floats finally arrived, packaged in a demure cardboard box. However lifting the lid revealed two beautifully moulded and carefully painted floats, crafted from thin fibreglass. Despite their impressive size they weigh only 150g each, although I am a little concerned at how the Trainstar will fly with this additional weight and drag.



The floats come with a pair of aluminium mounting struts and braces, as well as mounting hardware. There is also a nice rudder, although only for one side, and sleeved cables for actuation via the planes rudder control horn. There are also brackets provided for securing the cables on the float and to the plane.

A very nice set of floats which I look forward to assembling and installing to my Trainstar in the near future...

Trainstar Floats

...working this out

The landing floats for the Trainstar are really good however, not being specifically intended for the Trainstar, I need to figure out how best to install them.

So far I have decided to use the two undercarriage mounts on the Trainstar, the forward mount which is used as the main undercarriage mount in taildragger configuration, and the rear mount in tricycle format.

This seems to be logical, however it does require a custom float strut, as the rear mount is about 25mm higher than the front mount. Nevertheless, this shouldn't be too difficult to achieve (just getting some 2mm aluminium sheet and putting a few bends in it).

I have assembled the rudder, which just needed some cleaning of the mounting shaft to allow smooth movement, and the looped elastic-band works well to pull the pivoting rudder down.

At the moment I'm thinking that I'll use the provided cables to actuate the rudder, which connect to the rudder control horn on the plane. While I like the idea a direct-acting servo, this would require cutting a hole in the float which I'm not so keen to do...

Dawn of a New Era

...well two actually

A post office card on the doorstep advised that my parcel was ready to collect at the local. This was big news, heralding the dawn of new eras in flight; jets and seaplanes.

The package should contain one highly sought-after Stinger 64 electric ducted fan (EDF) jet. These planes seem very popular, hardly staying in stock at all before they're sold out again, attesting to their apparently good flying characteristics and high-speed fun.

There should also be a pair of 83cm landing floats, which will hopefully fit my Trainstar. They are the perfect size for a fuselage just over a meter long. I'm just hoping that the mounting points match up, but we'll make a plan if necessary. As soon as I saw that you could get floats I realised that I had to get some; floats planes are just so cool.

Now I just need to find a suitable lake where I can fly it...