Blackhorse Trojan (larger one)

[winchweight]

On another forum, there is a thread developing about the best and worst ARTFs. One of the replies states that the writer has seen two Blackhorse Trojans have their wings fold in flight. He intends posting pictures and I'll copy them here if he doesn't mind. Anyone had experiences of this?

[winchweight]

http://www.rcmf.co.uk/4um/index.php/topic,45266.msg497499/topicseen.html#msg497499

This link will take you to the forum and if you scroll through you will see the horrendous aftermath of a wing fold in flight! Apparently the post mortem showed that the wing tube passes through light weight formers, without any doublers or any reinforcement. Now this is were ARTFs get into difficulties, because, how do you check?

I would be interested in RCM&Es opinions, as I believe they reviewed this kit favorably quite recently? I am interested in buying one, but now I'm worried.

[David Ashby - Moderator]

Hi Shaun

Yes, not good.

Well the wings didn't fold on the review model otherwise we'd have said, the reviewer liked the model as you say.

I'd be interested to learn where the failure occurred on the wing, the area that failed must be detectable. The distributors - Ripmax need to be imformed immediately as it could be that a whole batch of kits is affected and other models are just waiting to fold.

I'll have a word with the reviewer to see how his model is fairing since the review.  

David 

[winchweight]

Hi David. I have asked for more info and will let you know.

[Jonathan Lewzey]

This must be a type error, but I looked at the link and the guy says he had an OS91FS in it. Isn't it a 25 size model? Has he just overpwered it an folded the wings pulling the turns too tight?

Jonathan

[David Ashby - Moderator]

Ah, good spot Jonathan.

There are two Trojans from Black Horse, we reviewed the smaller one but that in the pictures looks like the bigger one - according to the Ripmax website it is for .91 f/s. The smaller is for .25 - .39 two strokes. Will stand corrected of course.   

[winchweight]

http://www.ripmax.com/item.asp?itemid=A-BH045&SelectedTab=010

Not according to this link on the Ripmax site. It says it's for 60 2st or 91 FS.

[flytilbroke]

I had a look at the Ripmax site. Graham is correect, there are two sizes of Trojan. One, the smaller, is for electric or .25/.39 two strokes. The larger is for .60 2st or 91 fs.

[flytilbroke]

Got a PS. The pics of the remains do look like being the size for a .61 2st or .90 size 4st. In the pics it does look a bit weak at the wing roots too.

PPS, NOT GRAHAM . David

[winchweight]

Hi guys. Here's a bit more detail from the bloke who saw it go in and who investigated the cause a bit (he's an Experimental Development Inspector for a well know aircraft engine maker (fullsize!)). And a picture or two

I quote:

A gentleman who flys at our club airfield bought this kit and had flown it 9 times...this was its tenth flight...he's a pretty level headed guy...scale models I believe he has a couple of petrol jobies as well, nice models, straightforward type..no extreme flying or 3D hot dogging.

 IIRC the club Chairman...a well respected senior member of the LMA was present and the club Sec  certainally was. My son went out to help find the detached wing...initially they came back with empty hands... but just to fetch some transport rather than try bring all the bits back over rough ground, then all the debris was layed out to see it could be established what was amiss ( personnaly I'd rather do this back at home with some quiet dignity and engineering logic applied )

 The wing tube appeared to be made of rolled cardbord type of material..or a tube of some other substance covered in such to gain better adhesion to the wing ribs...the ribs themselves appeared to be only balsa ...pretty light grade stuff too...it looked like the outermost ( on the wing tube) rib had failed first along its centre line shearing the top and bottom T.E & L.E sheeting, then all the others must have quickly followed resulting in a catastrophic failure of the wing panel.

 Personnally I dont believe there is such a thing as a one off.. If this has happend once and unless there has been a change in process and practice ..it will happen again.

 A rather Sad end to this is that it was this gentlemans first ARTF.

 [img]http://www.rcmf.co.uk/4um/index.php?action=dlattach;topic=45266.0;attach=22097;image[/img]

[img]http://www.rcmf.co.uk/4um/index.php?action=dlattach;topic=45266.0;attach=22093;image[/img]

[Peter Miller]

The BMFA have a reporting scheme for ARTF failures. I suggest that it would be a very good idea to send this one in.

[winchweight]

I'll pass this on.

[Tentpeg]

Beware the Top Gun Ultimate.

Interplane struts are 'attached' to the wings (upper and lower) by 3mm screws into 3mm nuts which are supposed to be set in some sort of glue into a piece of ply on the ribs. Over this, to keep the nuts in place is a skin of 1/16th BALSA! I know, because I've been inside there.

Needless to say, on its' maiden flight, the strut on the port side departed the aircraft while in a gentle turn which caused the wing to flex and disconnect the top aileron on that side.

I got it down, with some difficulty upon which the carbon imitation undercarriage collapsed on one side. Although it was an emergency landing, it wasn't a heavy one so I sent the item back to CML and they, very obligingly, with no argument, sent a replacement, by return post. I also mentioned the incident with the very frail interplane attachments and they were very concerned and promised to look into it with some urgency. On the next flight, with suitably beefed up struts the aircraft performed beautifully. It really is a dream to fly, BUT when it landed (perfectly normal, no emergencies) it collapsed on one side again. When I called CML and told them the bad news they admitted that they had received quite a few back and were looking into it so it looks like a bad batch. I asked them if they could supply an aluminium one instead as this is what is described in the instruction manual. A much thicker aluminium version was duly sent. This is smaller in dimension from front to back and, as they mentioned in an accompanying letter obviously not intended for this machine, but could I make use of it?

If you have any problems contact Mr John Varley in Customer Services at CML.

Tel :- 01527 575349 or E-mail :- [email protected]

He is a very obliging guy and will help you if he can.

It's a good job that I am a builder of model aircraft from way back and was able to rectify the faults. I dread to think of the (dangerous) mess someone could make if they had only bought ARTF's in the past. They probably wouldn't bother and just junk it. Not a good way to encourage people to take up the hobby.

I'm all in favour of starting a campaign ( through the magazines maybe or even the BMFA) to promote the import of ARTC's so we can see what is going on under the skin and beef up where necessary. These would be subsequently cheaper, you would be able to choose your own covering (it's not that difficult with a bit of practice) and it would encourage the manufacturers to up their standards because we will be able to see any bodging etc..

Join the campaign for the NMA (nudist model aircraft) now!

Regards,

Tentpeg. 

[flytilbroke]

You are a lucky person to get a reply from CML. I tried for more than a year, direct and via dealers. After a year Paisley Models previously owned by a good aquaintance managed to get them to respond with the part I wanted. Needless by then really as I had used an alternative part.

[Terry Honey]

 Re Blackhorse kits. I had a Travelair. Tailplane snapped in level flight. Comlplained to Shop it was purchased from (Well known chain with shop in Bristol). Response was a shrug of the shoulders. Needless to say I don't purchase from them anymore ! 

[winchweight]

In contrast, I bought a secondhand Super Air, flew it to death and have now passed it onto my son. It's brilliant!

[Graham Trever]

I have flown my t28 twice now but do find the wings of a light build,very flexy and now I have read about the disaster of the other t28's I think  will have to build another wing or uncover this one and strenghten it,unless blackhorse are going to admid a too light a build .I will await any other reports on this model before the knife comes out.

[winchweight]

Let us know how you get on.

[Tentpeg]

Get the knife out now and don't take any chances!

One thing that I've just discovered is that by adding diagonal ribs between the existing ones makes a wing a LOT more rigid. I was following the advice of Alisdair Sutherland when I scaled up a much smaller model and was amazed at the difference it made. Try it, it's a very quick and effective remedy.

Regards,

Tentpeg. 

[Graham Trever]

Yes the diagonal thing is very good advice as that is what is used on roof building to stablise roof trusses.Will be getting the knife out.

Regards

graham 

[YakMad]

Tentpeg,

       I have the Top Gun Ultimate and I agree the undercarrige is rubbish, I changed it for a Carbon copy version but then the U/C mount pulled out, the interplane strut nut glued in wood fixing is stupid and I did manage to pull one out (hanger rash), I also braced the tailplane with carbon rod. It flies very well but is such a pain to put together at the patch (too many bolts and nuts) that I don't fly it often. I have also moved the CG back by about "4" inches and it flies even nicer. I won't be doing anymore mods to it, when it breaks next I will be making it fit into the bin. The best larger aerobatic bipe (for the money) I've  flown has got to be the CERMARK Pitt S2B (I am building a second one now) and the build quality it 4 or 5 times better than Top Gun. By the way I have had other models from Top Gun with similar problems to the Ultimate, let's just say I won't be buying anymore.

[Tentpeg]

Hi there, YakMad,

How does the Cermark Pitts compare in size to the Ultimate and what engine have you used?                                                                                                                                     My 'Ultimate' has a Super Tigre '90 which seems pretty adequate.                                          I have found from personal experience that 'Carbon Copy' U/Cs are made in the same way as the one supplied in the Ultimate kit and only have a very thin skin of carbon on the outer surface. It's only there for appearance. If anything it should be on the inside of the undercarriage legs for strength, but when I raised the question with them, suggesting that they put the carbon both inside and out, they told me that this would make them too rigid. Sounds like a b....hit, money saving excuse to me.                                                            Does anybody know where you can buy an undercarriage that is actually made of carbon fibre and not just coloured black to look like it?

Regards,

Tentpeg. 

[YakMad]

Tentpeg,

The Cermark Pitts is slightly bigger than the Ultimate, I've flown it with a 120 Saito and it feels less draggy than the Ultimate, I got my second one from Sussex Models reduced to £179 which for the quality and considering how much is done for you is excellent, also the interplane struts use the same fixing method as my Great Planes Skybolt, a nylon bolt which screws in by hand which means no small bolts, the cabane and cowl come pre-installed, the wings are joined, proper large wheels and spats to match, plus an Aluminium spinner colour matched to the model, robart hinges, bracing for the tailplane, need I go on. That's a bit worrying about the Carbon copy undercarriges although I did suspect they were not fully carbon, having said that they are much stronger and have not failed yet!. I also have a set on a Hanger9 Funtana which also had a rubbish "Carbon U/C" which cracked on the first landing and H9 were unable to supply a replacement.

[Tentpeg]

I think, if the supplier is selling goods which are not fit to do the job for which they are intended, he is obliged, by law to supply either a replacement or a suitable alternative. His other alternative is to offer a refund.

Please correct me if I'm wrong.

I must say that the people at CML have been very helpful to me with any problems and finally, after two failures of the 'carbon' versions, sent me a replacement undercarriage made of heavy gauge aluminium for the Ultimate. They freely admitted that they had received several other returns and were looking into the problem. Let's face it, no supplier wants any sort of problem or complaint if they can avoid it.

Tentpeg. 

[Brian Cooper]

I reviewed the larger Trojan for RC Model World.  I am happy to report that the model has been flying regularly for several months and is still flying extremely well.    It gets put through all the usual aerobatics and, so far, nothing has broken or fallen off.

I had a TopGun Ultimate which fell to pieces too.  Sadly, it only started to fall apart after the review had gone to print, and it was too late to "pull" it.    One to avoid. 

If you want a really good Ultimate, the Black Horse one is superb.  My one has been thrashed mercilessly for many months and it just keeps coming back for more.  It flies brilliantly and is a rugged beast which has stood the test of time.    

                                                                  

B.C.