Kyosho Trainer

SPECIFICATIONS

Stock Number: KYOA1260
Wingspan: 63 in (1600 mm)
Wing Area: 651 sq in (42 dm2)
Total Weight: 5.2 lb (2350 g)
Fuselage Length: 49 in (1250 mm)
Requires: 2-stroke .32-.46 cu in (5-7.5 cc), propeller, spinner, 4-channel radio w/4 servos

I recently returned to modelling after many years and, after various false starts, I purchased a Kyosho Trainer to learn to fly. This is how I got on with it. Now if you are experienced then much of what follows will probably be obvious but a Kyosho trainer is intended for a beginner and so are these notes. I made some mistakes but then that’s the only way one learns isn’t it?

OK, so what’s in the box? A fully built fuselage, wing, fin and tailplane, and various bits of hardware. The kit is very complete but some of the items are of dubious quality/use. To complete the kit you also need 4 channel radio, epoxy glue, a 40 2-stroke, sponge/foam sheet and a few hand tools. I will go through the build in the same order Kyosho do. Mick Charles (model shop) reckons it takes a couple of evenings to build; well it took me rather more than that.

The flat bottomed wing is in two halves joined by a very substantial ply brace. In the centre is a preformed hole for the aileron servo and before you glue the wing together check that your servo will fit in the hole. Mine didn’t and it’s a lot easier to enlarge it while the wing is in two bits. Trust me. The instructions specify two part epoxy but make sure that you get 30 minute i.e. devcon or similar, and not 5 minute i.e. rapid araldite. If you use 5 minute you will be very short of time while assembling things. The halves fitted well on a dry run and, with epoxy everywhere, I joined them together. I had trouble keeping the halves aligned and closely together. In the end I wound up with the entire wing vertical and used my fingers to check the alignment was correct. It came out all right for me but I’m sure there must be a better way; the thing is once the glue is on you are committed! I tried horizontal and packing the tips up but I couldn’t keep the two halves closely together.

Next, there are two ply pads to glue on to mount the servo onto. I filed a couple of slight flats on the wing and kept the pads in alignment by sticking them to a flat piece of balsa with some double sided sticky stuff and then glueing to the wing. The ailerons have torque rods fitted and these connect to the servo by bits of wire with a z bend on one end.

The attachment to the servo arms is by what Kyosho call a "linkage stopper". These are round pillars with a reduced section that passes through the servo arm and are retained by a tiny circlip. The wire to the torque rod passes through a hole in the pillar and is fixed by a grub screw. These allow for very easy adjustment of the wire position but are quite critical to assemble. The standard Futaba servo arms are a fraction too thick which means you need to reduce them with fine abrasive paper. This is the critical bit: too little removed and you can’t get the circlip on or the pillar can’t rotate, too much removed and the pillar will be able to tilt introducing slop into the control surfaces. I used them but I really don’t like them and would prefer a more conventional connection to the servo arms.

A two part engine mount is supplied, with engine mounting holes pre-drilled. According to Mick Charles, theirs just bolted in place and fitted an OS40LA perfectly. Well my mount is slightly different and the holes are too far apart. I got round this by bending the arms of the mount in a bit and opening out the rear holes a little. This works and the engine is still straight but it would have been better, I think, to elongate the holes in the firewall. The mount halves are bolted to the firewall using the nuts and washers supplied. You cannot get at these nuts without removing the fuel tank which is sealed in place with silicon sealant, so removing it is a real pain. I managed to get some nutlock on the threads and did them up really tightly using a minature socket set. Given the difficulty of getting at these nuts it would have been better to junk the nuts and use captive nuts such as supplied for the wing bolts. The same applies for the nuts securing the steerable nosewheel mount.

The fuel tank supplied is a very poor quality item only having two pipes, one of which needs to be bent. On mine, the hole on the tank was very poorly trimmed and I had to re-trim it with a scalpel quite a lot. There is a hole in the firewall for the neck of the tank. No matter how I tried I could not get the tank to go in properly and sit flush against the firewall as it is supposed to. Mick Charles managed it, I don’t know how, but I found the bolts sticking through the firewall made it impossible. Mick Charles said "Oh, you just have to get tank up high ". Well not on mine you couldn’t and after a very frustrating evening I abandoned the wretched thing and bought an 8oz Kavan tank. I put in some foam and some sealant and the whole thing slid into place in couple of minutes perfectly (and I’ve now got three vents).

Three small blue foam wheels are supplied. The people at Kyosho must be colour blind. After the first flight my instructor said there was a lot of rolling resistance and so they were replaced with some 2 1/2 inch wheels which are much better. The wing is retained by two dowels at the front and a couple of metal cap screws, with captive nuts, at the rear. It was pointed out to me that if I piled it in then these would rip out causing a lot of damage to either the wing or the fuselage and so I replaced them with slightly larger 5mm nylon wing bolts.

These are glued into place with epoxy after trimming away the film covering. The joints are strengthened by four triangular fillets and again you have to trim away film. The instructions say to glue the fin and tailplane in place, then to trim away the film where the fillets will go and then to glue them. I found this difficult not least because there was a smear of epoxy to cut through and you must be careful not to cut into the actual fin, tailplane and fuselage. It would have been much easier to dry assemble everything, mark where the fillets are going to go and then do the trimming while everything is still in bits. In the event the tailplane was well glued in and supported so I only fitted the two fillets for the fin.

Fitting the servos would have been a whole lot easier if I had realised at the start that the ply servo mounting tray does in fact come out. It does, it’s very tight but it does. The holes shown as being used for the push wires (snakes with a metal wire inner are fitted) give correct control movements except for the steerable nosewheel. After the first flight my instructor reported that the nosewheel had far too much movement and so I changed to using the innermost hole at the servo and the outermost hole at the nosewheel itself. This also puts much less load on the servo in the event of hitting a tuft of grass or lump of mud.

The control throws specified are fine, don’t exceed the aileron throws - they are quite sensitive. I put my receiver and battery as far forward as possible, wrapped in foam. I used some 1/4 square balsa to make some retaining rails on the fuselage sides and some 1/16 sheet to slide in and retain everything, held by the sponginess of the foam.

Mine needed nearly 5 oz of lead up front. That seems an awful lot but there was no doubt about it and the R/C gear was as far forward as I could get it. Needless to say Mick Charles didn’t need any. My instructor checked the plane over and "volunteered" for the maiden flight. The engine had had a couple of tanks through on the bench, so we fired it up, set it rich and wound it up at the end of the runway. To my amazement it soared into the sky! And fly it does, according to my instructor quite nicely. Loops and rolls are fine but Kyosho stress that the model is not aerobatic (I’ve seen pictures of the result of someone attempting a "split-s", whatever that may be, and the wing folded in half). Apart from the wheels, noseleg movement and a couple of clicks of trim she flew straight out of the box.

The OS40LA has proved very reliable and easy to use, apart from a minor problem with some dirt in the fuel line. I fitted the OS Super Silencer and a 10x7 APC prop. The combination is extremely quiet, indeed it is hard to tell if it is still running while in the air. The engine provides ample power and the plane flies quite happily on less than half throttle.

I have since had several flights myself and I’m very pleased. The colour scheme is "high visibility", or to put it another way, the upper sufaces are very pink (the underneath being white). I’ve had to suffer various comments on the colour but it is very effective. I have had little trouble keeping track of which way up it is and where it is going, and I am not suffering the disorientation I was before.

So the Kyosho trainer is as success as far as I am concerned. I have every confidence that it will be third time lucky and that I shall at last learn to fly R/C. My thanks to all who have helped me, and particularly to Richard Hawke whose patience and calm "I think you better you better give me the transmitter now ..." has been tremendously reassuring.

 

1. Engine. I have subsequently fitted an OS52 4-stroke simply to run it in. This works brilliantly. I initially flew with an 11x8 Graupner propeller which was fine but it was still flying quite happily with the throttle on tickover, so landing speed was manageable but quick. I changed this to a 12x5 and it is much better. Good acceleration on takeoff and it slows really well when you throttle back for landing. It now needs half the runway length to land that it used to. I no longer needed any lead up front and it fits the engine mount better. It has been suggested to me that an 11x6 prop might be better. The combination is so good that my 2-stroke is now up for sale and I’m sticking with the 4-stroke. It sounds lovely and flies like a dream.
2. Battery. The club have found that you can get them to balance without lead (and an OS40LA) if you fit the battery under the tank.
3. If the field you fly from has a good strip, preferably mown, do fit the steerable nose wheel. It makes ground handling much easier.
4. Rudder. The wire linkage to the rudder is very stiff, the rudder doesn’t always centre properly and the servo can buzz. Take great care to get free movement with the rudder.
5. Receiver on/off switch. Do put the switch on the opposite side to the exhaust, it stops it getting covered in fuel, oil etc which really doesn’t do it any good.
6. Elevator movement. Do make sure you really do have the elevator movement specified – do not reduce it, you may need it all. I have.
7. Not really related to the Kyosho trainer but do get a buddy box setup for learning to fly. I am learning to fly much faster now and have just done my first landing. The buddy box setup has made a huge difference.

 

Article by Simon Bisson from Leatherhead MFC
31th August 2001

Comment by Ray Raike on 00000000000000. Rating none

Good review. Just a couple of extra bits that might come in handy. I've had two of these very fine planes, (I lost the first one in a mid air, smashed to bits but the wing survived)nobodys fault, just one of those things. It is a good idea to strengthen the firewall with an extra piece of ply because, as a learner, you tend to land a little hard and the nosewheel assembly has a tendency to rip out of the firewall. The second plane was modified before it went into the air and I have had no problems. The plane is quite aerobatic in a loose sense of the word PROVIDED YOU GLUED THE WING TOGETHER PROPERLY. I have been flying this plane for about nine months doing all sorts of tight turns rolls etc with no adverse affects and it handles everything I throw at her.I am now going to convert it into a camera plane. Great review, great plane and Great FUN.

Comment by dennis.lee on 00000000000000. Rating 4

I was taught to fly with this plane 3/4 years ago and after numoures crashes and repairs it still is very flyable . I thorouly recomend it

Comment by Joe O'Brien on 00000000000000. Rating 4

Excellent trainer, however the covering is brittle on the areas of open structure. Don't try to shrink it, patch it or recover it

Comment by Martin on 00000000000000. Rating none

One question , has any body tried electrify this trainer? What is the experience?

Comment by on 00000000000000. Rating none

GO FOR THE IRVINE TUTOR 40 IT'S THE BEST. THIS PLANE shit

Comment by Dave Davis on 00000000000000. Rating 4

I'm an experienced aeromodeller who likes training beginners. I paid £40 for a used Kyosho Trainer with an OS40LA up front. It flew well until the clunk got hooked up, causing the engine to cut and it came down in the spuds ripping out the nosewheel and most of the front of the fuselage. I'll repair it one day. This aircraft is not "shit", to use the description of one of your other correspondents, it is like most Kyosho products, very good. The colour scheme, whether pink or yellow is very helpful to beginners. Where I will agree with that correspondent however, is in his assertion that the Irvine Tutor is the better trainer. I put this down to the semi-symmetrical wing section on the Tutor as opposed to the flat bottomed one on the Kyosho Trainer. May I suggest that if the other correspondent wants a "shit" trainer, that he try either the Yamamoto or the Hiboy. Dave Davis Shropshire

Comment by on 00000000000000. Rating none

is any people selling any planes what are peti

Comment by Matt on 20041231040849. Rating 4

Ive just put together my Kyosho Trainer and am about to fly it im sure it will all go well for me and thanks for all your fine tips.

Comment by Sam on 20050824074410. Rating 5

Great review. I had the kyosho calmato (the newer version of the 40 trainer) It flew alright but wasnt the best i now have a scanner which flies beutifully. As for that other guy peter norris some shit on the s if you want to call someone that has contributed to the site abuse, than dont ever return to this site again.

VIEW / ADD Your Comments This is where you can leave your comments about the article itself or about the subject of the article. For example maybe its a review and you would like to tell people about the experience you have with this particular model. Name: Email Address (optional): Rating: 1 2 3 4 5 Excellent = 5 Comments: