FMS ASW-17

Andrew James snaps together a quick build, semi-scale glider from FMS.

At 2.5 metre wingspan this quick assembly kit follows in the footsteps of FMS’ 3m and 2.3m Fox gliders. In full size terms the Fox is an out and out aerobatic machine while the ASW-17 is an Open Class thermal hunter. Both models look the part, but I am guessing that more compromises have had to be made with the ASW to make it a tough and durable R/C model.

Andrew James snaps together a quick build, semi-scale glider from FMS.

At 2.5 metre wingspan this quick assembly kit follows in the footsteps of FMS’ 3m and 2.3m Fox gliders. In full size terms the Fox is an out and out aerobatic machine while the ASW-17 is an Open Class thermal hunter. Both models look the part, but I am guessing that more compromises have had to be made with the ASW to make it a tough and durable R/C model.

Whilst the full-size Fox is quite chunky, which the FMS models replicate well, the ASW is a much more streamlined affair, at least in my eyes, and if this was slavishly followed using the modern moulded foam techniques that FMS are so well known for then things would probably be a bit weak, especially at the rear fuselage, which tapers to a very slim cross-section where it meets the base of the fin. Hence the model is a bit more generous in this area, and the wingspan is also a bit more compact than you may find with a large scale moulded ASW-17 model. But having said that she still looks like an ASW-17, albeit with a solid foam canopy.

mar21asw2

For a foam glider FMS have done a great job of replicating the ASW-17. It really looks the part.

FMS have avoided going down the red nose and wingtip liveries associated with this marque, opting instead for an all-white colour scheme that requires minimal sticker work in areas that would be prone to decals lifting, especially around the nose. Instead, you get a vivid green flash running down the fuselage on each side, just under the canopy, and an eye-catching Choco Fly graphic that wraps around the fin. A couple of large FMS and Swiss registration stickers adorn the top of the wings.

That Choco Fly graphic had me stumped for a while, especially as I spent most time looking at it from the port side, where it looks like Oco Fly. Then it dawned on me to follow the logo all the way around the fin and Choco Fly was revealed. A quick search on Google came up with the surprising result that Choco Fly is a Swiss model company who specialise in high performance scale and sport gliders moulded in carbon, so I guess this design may be a collaboration between them and FMS? But don’t quote me on that!

Snap Together

Cleanly moulded from white foam, with plastic and metal parts in critical areas, the ASW-17 is advertised as a snap together kit and offers very speedy assembly.

First job is to snap on the rudder to the fin at the three hinge points. Click and the job was done.

mar21asw3

Rudder ready to snap in place on the fin.

Next up was the tailplane, which has a plastic moulding in the centre that slots and snaps into a matching part fitted to the base of the fin. Click and… hmm, well no click actually. Despite several attempts I could not get the catch to engage. With a photo/flying session booked for the following day it was important to finish the model so I took the decision, based on the fact that if the catch had worked the tailplane would be permanently fixed in place anyway, to apply some 30-minute epoxy to the outer faces of both mouldings, leaving the slot, rail and catch parts of the assembly clear so that I could disassemble it later for further investigation. Well, that was the plan, but – you’ve guessed it! – the glue is still there! But hey, it provided a quick fix and is working well, so I’m happy to keep flying her.

If the catch had worked assembly time to this point would have been measured in seconds, but even with some gluing time and a cup of tea it was still less than an hour, so I was still well on track for flying the next day.

mar21asw5

The catch deep inside the tailplane’s central moulding didn’t fully engage so 30-minute epoxy was used on the outer faces as a temporary measure. It’s still there!

The 9g rudder and elevator servos are connected using short pushrods, with Z-bends at the servo ends and the other ends pushing into robust dual control horns fitted to each control surface. Pivoting between each of the dual horns is a brass barrel. The pushrods slide into these barrels, where they are locked using grub screws, which makes them easy to set up when the radio is switched on and the servos set to neutral.

Wing Installation

The wing rods are sturdy 9mm diameter metal affairs but rather than going right through the centre section of the fuselage they simply screw into matching metal inserts fitted to the strong plastic moulding embedded at each wing root. The forces at the ends of each rod must be huge in flight, especially when doing aerobatics, but so far, after many flights, it seems a robust solution and certainly aids quick assembly when at the flying field.

mar21asw6

Wing root detail showing the plastic sub-spars, the wing spar receptacle and the generously sized servo connector. Plug & play!

With the rods in place the wing panels can be slid on until they too click, denoting that the fore and aft plastic sub-spars have fully engaged.
Each panel is fitted with a pair of 17g servos, one each for the ailerons and flaps. Hook up is again via those sturdy dual control horns, although this time the pushrods are factory fitted.

mar21asw7

Top view with the wing spars screwed in place.

mar21asw8

Factory fitted 17g wing servos are connected to dual control horns using short, straight pushrods.

The leading edges are fitted with full span plastic shields, which protects them from the inevitable dings that foam glider wings get when landing on anything other than really short grass. A nice touch.

mar21asw9

Ingenious wing root mouldings feature spring loaded sub spar locks.

That’s it – assembly done. Had the tailplane catch worked building time would have taken mere minutes, but even with a spot of glue it was all done in less than an hour.

Radio Bay

The large, grey painted canopy covers the radio/battery bay. It is held in place at the front by a generous foam ‘tongue’ and at the rear by a strong catch. This one worked faultlessly, which is great as large canopies sometimes have a tendency to come loose, but I can’t see that becoming a problem with the ASW-17.

mar21asw10

There is loads of room to mount a 4S LiPo and a generously sized receiver. 35MHz anyone?

Inside there is plenty of room for moving a 4S 2200mAh LiPo around to achieve the recommended balance point between 70 and 80mm back from the wing leading edge. The battery area comes ready fitted with a long strip of Velcro for securing your pack, backed up by two hook and loop straps.

mar21asw11

Close up on the neatly faired spinner and powerful folding prop. The ESC is set up to brake efficiently.

Even with a LiPo installed there is stacks of room behind for any modern receiver – or even a slightly older boxy one if that’s what you have! With such a spacious interior this could be the perfect aircraft to give a 35MHz radio set an airing…

mar21asw13

In-board flap ends are kept in shape using neat plastic mouldings.

I used a six channel Spektrum receiver to operate the ASW-17, sticking with the supplied aileron and flap Y-harnesses. But separate wing controls would be easy to set up if you prefer.

One thing that impressed me was that the flaps really do work and can be made to fully extend without the servos starting to complain. Flap movement with some ARTF models can be a bit marginal, to say the least, so seeing the full range of movement available when operating the flap switch was very pleasing indeed. In anticipation of some trim change when deploying such powerful flaps, I made sure to include some down elevator compensation, which I could fine tune at the flying field.

Although this is such a simple model to build it benefits from a well-presented instruction manual. This gives both high and low-rate settings, which are well suited for the first flights and which can be tweaked to suit personal preference during later flying sessions.

At The Field

For the ASW-17’s first flights I took the model along to a thermal soaring session at my local gliding club. Recently I have been flying a high-performance moulded glider there, so I wasn’t expecting too much from the comparatively chunky ASW when it was sat alongside the sleek F5J soarers lined up behind the cars. But, as the saying goes, don’t judge a book by its cover, and I was pretty pleased at how things turned out…

mar21asw15

Just before her maiden flight the ASW-17 basks in the late autumn sun.

For the first flight I asked clubmate Steve for a hand launch. We agreed that a power off glide over the long grass would be a good idea to test the trim, so with a firm heave Steve let her go. Well, the resulting very short flight is best described as a belly flop! After a quick check over we tried again, but this time at full power. With no shortage of get up and go from the Predator 750kV motor the ASW-17 was quickly away and climbing fast, with no trim issues to cause any concerns.

mar21asw16

A pensive Steve holds the model aloft just prior to its first test glide – a.k.a. belly flop!

With the power cut it was time to check the glide trim. As with the climb there was nothing much to do in this respect, with just a few clicks of up being needed to slow her down as she roamed the sky. No major turning effects were noted so the aileron and rudder trims were left untouched.

mar21asw17

In her element and powering through for a low camera pass.

Being a bright, late autumnal day, the air was quite buoyant and whilst there were no strong thermals to exploit the ASW-17 returned some pretty good glide times following each climb to height. Handling at the low-rate settings was very pleasant, so for general sport flying I see no reason to change things.

With several moulded gliders sniffing the same air I was pleasantly surprised to see that the ASW-17 was more than holding her own. She raised a few positive comments from other clubmates too, so things bode well for those fine flying days to come when the thermals are booming, and lift is abundant.

With my F5J moulded ship running on small 1000 mAh packs I am used to landing after three or four climb and glides, but with the larger 2200 mAh LiPo in the ASW-17 you can comfortably extend this. I wouldn’t go too much further though…

mar21asw18

A wingover shows off the model’s planform to good effect.

Lining up for landing, I dropped the first stage of flap and was pleased to see that the amount of elevator compensation I had employed was just about right. This followed through at full flap and the ASW-17 settled down in a very controllable descent.

Landing into grass with full flap is not recommended with any glider due to the strain that hitting the turf could put on the control surfaces and their servos and linkages. So, I made sure to pop the flaps back up again just before a clean touchdown. Nice job, FMS!

After a couple more packs doing what the ASW-17 is designed to do, searching for lift, I dedicated my last LiPo to exploring the model’s aerobatic potential. Selecting high rates and diving to pick up speed from a decent height the ASW carries plenty of momentum to whistle through loops, long rolls and wingovers. So, if performing aeros with a scale looking glider is your thing then you won’t be disappointed. And if you do let the airspeed bleed off a bit too much then that powerful motor and prop combo is always there, ready to get you out of trouble.

Off My Trolley

In the storage shed at a local power club I have often spied a launching dolly but until now I’ve not really had a model that could take advantage of it. But the ASW-17 was the perfect candidate to try some fun ‘off the trolley’ flying.

My clubmate, Frank, explained that the dolly had been designed and made ‘in house’, so to speak, by club members many years ago; I have been in the club for several years and have never seen it used, so it would be fun giving it a try.
Unhooking it from the wall, Frank spun the tyres and adjusted one slightly stiff wheel. Other than that, it all looked good and the ASW sat on it well, so we walked over to the patch to give it a try.

Although the grass was not at its shortest, this being a winter’s day, the ASW-17 accelerated quickly, and a touch of up elevator soon had the nose up and the model climbed away in the same spritely fashion as during the maiden flights. In fact, I pulled her off a bit too quickly and the imitation tailwheel momentarily caught in one of the dolly’s spacing rods. So, for take-off two I made a conscious effort not to touch the elevator, although instinct soon took over and I did give it a gentle tug, just clipping that tailwheel again, but much less severely this time. Third time lucky and this time I resisted temptation and let the ASW-17 rise off the ground in her own time. In truth this wasn’t too much further down the runway and she was soon climbing away with gusto once again.

mar21asw20

A take-off dolly provides an alternative way of getting this pretty glider aloft.

Although I have been flying R/C models for well over forty years I have to say that I’m not the world’s most confident hand launcher and I much prefer to ask a clubmate to do the honours when someone is available. With the ASW-17 hand launching is not a problem due to the power available, as Steve proved during the maiden flights, but at my local power club I now have an alternative solution for those time when a trusted ‘lobber’ is not available.

Of course, it’s still handy to have someone walk out with you, to collect the dolly, as leaving a bright red go-kart in the middle of the runway wouldn’t go down well with other pilots!

Any Issues?

Just one. Before flying from the dolly, we noticed that one of the flaps was starting to separate from the wing. Not by a lot but it was obvious that left alone the gap would spread so the hinge line will need to be reinforced with tape.
To prevent any further strain on that flap the model was landed ‘clean’, coming in quite flat from a long way out. But with such passive handling it was an easy task.

So do keep an eye on the hinge lines and take remedial action to reinforce the hinges if necessary.

Conclusion

I haven’t had the chance to try her from the slope yet, but I have no doubt that she will be a more than capable performer when gliding in slope lift too. My only regret is that flying a powered glider from my local hill is a no-no (at least in terms of switching the motor on!) so this one is probably best kept for those hills where you can soar and then power up a trickle when the lift dies off, just to help with landing. (Any more than that and what’s the point? You may as well go flat field flying!)

Despite that recalcitrant stabiliser catch the FMS ASW-17 still went together really quickly. The end result is a sturdy semi-scale airframe that offers a fine soaring performance, whether that be thermal hunting or stringing together a suitable selection of glider style aerobatic manoeuvres.

So, if a quick build, moulded foam glider is on your wish list then the 2500mm FMS ASW-17 comes highly recommended.

DATAFILE
Name: ASW-17 2500mm
Model type: Moulded foam semi-scale glider
Manufactured by: FMS
Distributed by: CML
www.cmldistribution.co.uk
RRP: £279.99
Wingspan: 2500mm (98.4”)

Length: 1390mm (54.7”)
All-up weight: 2350g (82.9 oz)
Wing area: 50.3 sq.dm. (780 sq.in.)
Motor: Predator 3541 – 750kV
ESC: 40A
Battery: 4S 2200mAh LiPo
Functions (servos): Ailerons (2 x 17g), elevator (1 x 9g), rudder (1 x 9g), flaps (2 x 17g), throttle (ESC)
Required to fly: Transmitter, receiver & LiPo