John Muir

The J'En 57 is a 40 sized engine, in terms of dimensions and weight. I wouldn't put it in something designed for a 60 as it might leave the model tail heavy and possibly underpowered. Loads of models to suit: BH Speed Air/Travel Air/Renegade Seagull Low Wing 40. Pulse XT40 (lovely model, but spats puncture wing if you mess up a landing). Wot 4. Acrowot (needs built). etc, etc. Loads of power for any of these, but better to err on the side of overpowered if you want to fly aerobatics.   John.

It's probably a bit late to be coming back to this now, but regarding that 3536 motor I use, remember I am using it with a 7 cell nimh, which is roughly similar to a 2S lipo. It could be too much on 3S, but the great thing about electric motors is that you can simply use a small prop to tone them down by reducing the current draw. The bigger motor does help balance the model and you'd be using the motor well within its design limitations so shouldn't do it any damage by pulling too many amps through it (or the esc). I fitted mine behind the front bulkhead with screws into the front of the motor so didn't actually need a mount. It wasn't possible to add downthrust fitting it this way so I mixed down elevator to the throttle in my transmitter to stop it climbing madly. I had to experiment a little to get it bang on, but it works a treat. I use a hobbywing esc by the way, with the programming card, and that works well and was very easy to set up.   Did you decide what to do, and if so, what did you end up with? Just curious.   John.

A man of your word Ed.   Nothing competitive for me. I only know one other guy locally who slope soars. I used to fly balsa and veneered foam rudder/elevator models years ago and still have a Chris Foss Middle Phase which I flew not so long ago, but last year I discovered the joy of EPP in the form of the SAS Wild Thing, a simple 46'' span flying wing with elevon control, and haven't taken the Middle Phase out since. Tape covered EPP is so tough that I can happily fly from the heather clad and rock strewn hillsides in my locale without worrying about breaking it. It's also a convenient size, which makes it easy to cart up the hill. Here in Scotland we have plenty of hillls, but try finding one with a road or car park anywhere near the top! We build our roads around hills here. So something light and manageable is handy for the hike to the top. On top of all this, the Wild Thing is an excellent flying machine and can fly in a wide range of wind speeds. Brilliant fun all in all. What more could you ask for. Oh yes, of course, it's also cheap.

Paul, I think the motor/esc combination you're considering might be a bit lacking in grunt compared to what Mike and I have used. It will probably fly, but not that much better than it would on the 600 can. My set up would cost about £25 all in. Mike's gone a more exotic route, his motor alone costs about £80! If you do try the set up you've linked to, you really will struggle to get the CoG far enough forward without adding lead to the nose as all the gear is very light. The cheap GC motor I'm using can of course use lipos if you want, either 2 or 3S, but would need a smaller prop on 3S to keep the current under control. I'd do a bit more research if I were you before spending anything. On the other hand, if you've got the lipos already and you get your set up for a tenner, what's to lose? Give it a shot and let us know how it goes.   John.   Crossed with Wingman there. Now there's a man who knows. Save up an extra few quid and get something from Giant Cod that you know will work. Safer than buying from E-Bay as well.Edited By John Muir on 21/04/2010 08:49:51

Ed, you certainly know how to ask an interesting question.   I don't even fly gliders all that much, but you got me thinking. I certainly can't comment on pilot preference as I've never flown a full house glider.   As for the UK being windy, well that's why we're so into slope soaring.

The biggest difference IMHO is in the way the rudder works (so no problem there then, I hear you all shout). On the vast majority of high wing planes if you apply right rudder you will get a fairly immediate right banking turn. On a well sorted low winger, with the right amount of dihedral, applying right rudder will give you a right yaw, but no immediate roll. This actually makes a good low winger easy to fly as you can use the rudder to make corrections on approach or in crosswinds without dropping a wing. Otherwise a Speed Air with a 53 will go a lot faster than an Arising Star with a 40 (obviously) and should be a bit more 'precise' in the air. On the other hand it will slow down nicely for landing if you use the throttle carefully and won't be any more difficult to fly. In fact, by the sounds of things, you'll probably find that, because it does what you tell it to more accurately, you'll find it easier and more rewarding. Hope you enjoy it.

Erfolg   You're probably right. The OP was about thermal duration soaring but there are, apparently, numerous different versions of this. Electric powered or winched. Floater or 'penetrator'. And so on. I think the crux of the original question was do ailerons make for a more efficient glider? My point was really that we can't tell. Using only rudder or only aileron (leaving elevator input aside) can't be very efficient either way. Rudder only yaws the plane into a boat turn, then the inside wing drops into a bank. Very draggy. Aileron only rolls the plane, then it slips into a turn. Also draggy. With ailerons on a high aspect ratio wing, you also get rather a lot of adverse yaw, which points the nose out of the turn, even more drag. So yes, you can get more efficient turns using ailerons, but only if they're used with the correct amount of coordinated rudder. And that's very difficult to estimate if you're standing on the ground with no instruments. Very interesting question actually. It is relevant to all models to some extent. Most of my power flying pals, if asked this question, would probably say 'what's a rudder?'.

My first thought was 'full house', obviously. When did you last see a full size glider without ailerons? But the full size has the advantage of a pilot with a turn and slip indicator and is turned using both rudder and ailerons. Roll into the turn with ailerons and kick in rudder to counter the adverse yaw. If you only use one or the other, then either way, you'll get a skidding or slipping turn which is very inefficient, and you'll lose height. Now how many model glider pilots use co-ordinated rudder and aileron to make a turn? And even if they do, how do they know they've got the balance right? So I reckon, from an aerodynamic point of view, it probably makes very little difference. Models probably don't make very efficient turns either way. For a polyhedralled floater, rudder will do nicely as it will roll itself into a turn adequately. For a high speed slick model, ailerons will be best because on rudder only the thing will probably skid sideways for a while before rolling into the turn. Better to 'bank and yank'. I only fly a rudder/elevator electric glider with lots of tip dihedral and you can see that if you apply gentle control inputs it turns quite flat. If there was a pilot on board he'd be grabbing for the stick and trying to roll it into the turn to put the ball in the centre. But for my model it works fine.  

I have an old BMI Montana, which is very similar to your Alpha. I fitted one of these: http://www.giantcod.co.uk/xyh3536-1000kv-brushless-outrunner-p-405124.html with a 40A speed controller. I kept the seven cell nimh packs I'd been using with the 600 can motor as changing to a lipo would have caused CoG problems and cost more. A folding 11x6 propeller finished it off. The difference had to be seen to be believed. It now climbs out at something like a 70 degree angle and only needs about ten seconds run to get too small to see. I don't know what the current draw is, but nothing seems to get hot. A friend used a similar motor in his Protech Alpha, but with a much smaller prop. It went a lot better than with the brushed motor, but not as well as mine. Another chap has a smaller 28mm motor in a similar model and it doesn't seem that much better than stock. It may be under propped though.   I don't know much about electrics (Iusually fly IC models) so I picked the 35mm outrunner simply because it was the biggest diameter that would fit inside the nose of the glider. May have been overkill, but works well. HTH.   John

Very interesting survey - well done BEB. Unfortunately, to find out if we are, in fact, an aging hobby, you're going to have to do it again next year, and the year after and so on, to see if the average age trend is upwards or downwards. After all, last year, the average age might have been 62. Nobody knows.   What the results do show is that this is an 'elderly' hobby. I don't think this is a surprise, and I would theorise that it has been so since radio control became the norm and CL and FF were marginalised. After all, what do you need to participate in the hobby, as we conventionally practise it? In no particular order: money, free time, transport, patience, perseverance, money. Who has these things? The retired, mainly. Young people want convenient, cheap, instant gratification in the main (always did, even before computers) and don't want to join a club full of old fuddy-duddies. Even as we worry about why they're not taking part, they are down the local park flying 3D with the latest ready to go foamy. They'll lose interest next week, but will appear at a flying field in thirty years time saying, 'I always wanted to build one of those but never had the money/time/car' (delete as appropriate).   I have magazines from the seventies with letters bemoaning the lack of young blood in the hobby and yet, here we all are. We should stop worrying about attracting the young, accept that what we do appeals mainly to old men with youthful brains and have fun.  

1. 53   2. I/C sport   3. 10-12, Mercury Magpie FF glider    

Mode 2   East Scotland (Dundee)   East Scotland (Dundee)   Instructor   (In our club of 71 members we have 3 mode 1 pilots. One learned abroad, one in England and one switched as he found it easier)

Thanks for fixing that Phil.  

Oops, I messed up that link I put in a few posts back, and forgot to put in a description. So now the text is disappearing under the adverts up the right hand side. Sorry 'bout that. Won't happen again.

Doesn't matter if it's full size or model size, aeroplanes is aeroplanes and physics is physics. We can't even blame aerodynamic differences because we're talking about effects on the ground. So I'll stick with what makes most logical sense to me and which seems to support my own observations.   But hey, each to their own      John.

EAA   Scroll down to page 3 for an interesting article by a hands-on engineer on the toe-in/toe-out debate. This guy seems to have practical piloting experience to back him up. Very similar conclusions to PDR on RCMF.   I have to say that a couple of my models with wire taildragger undercarriages have 'acquired' some toe out (not to mention negative camber) over the years and seem quite easy to handle on the ground. I removed the toe out from one smaller model by manfully twisting the legs till the wheels had a touch of toe in, but I thought it made the plane more of a handful on the ground, so put it back where it was before.   Toe out for me.   John.    Edited By Phil Wood - Moderator on 01/11/2009 18:36:49

I think it's that smelly old stuff you used to have to put on with a brush. What was it called? Paint? It is a lovely finish. Isn't it a Super Sixty? Over an hour flying a Super Sixty? I'd have dozed off. Haven't a clue about the mystery models though, sorry.   John.

I'm trying to deregulate the flying of lightweight models at my club but there is no way I am going to be happy to let any old fool who hasn't flown for twenty years turn up at our field and start chucking a forty powered aerobat about willy nilly, just because he's says he's good. Like most people with any common sense (the favourite phrase of he anti-rule brigade) I like to make sure that the people I am going to be sharing a field with have at least a basic level of competence ( no guarantees, I know) so that I can feel relatively safe in their company. The A or bronze test is as good a way as any of acertaining this. Whether a club actually needs to rubber stamp the A certificate or not is up to them, but to not have a test at all is asking for trouble. I remember the old days too. I remember meeting a guy with missing fingers. I remember the cuts I picked up myself. That's why I use a stick now and strongly recommend others do the same. I too had a long lay off and returned. I bought a Seagull Boomerang as a refresher model and wasn't allowed to fly it solo till I sat my test. It was inconvenient and faintly irritating but I did it because a) them's the rules b)I wanted to make sure everybody knew I could do it and was, therefore, reasonably safe c)practising for it brought back my flying skills quickly, in a structured way and reminded me of the basics. If I'd gone straight back in with an aerobatic model I'm pretty sure I'd have ended up with some bad habits and possibly a broken model. Elderly returnees are common in this game and I have a certain sympathy with the 'never needed a certificate before, nanny state, health and safety police' attitude (I am almost one of them, but I'm only a youthful 52) but the world moves on. Models have changed. Flying fields are busier. Attitudes have changed. Live with it I say.

My club, of which I am secretary, insists on the SAA 'bronze' (BMFA 'A' equivalent) before you can fly unsupervised. This has worked well for years. However, lately we've had an influx of new members who have some experience on 'park flyer' foamies and can fly these perfectly well, but can't use them for their bronze test because they don't have wheels, or won't take off from our grass. They generally want to progress to bigger, more traditional models and take their bronze, but in the meantime, technically, can only fly with an experienced bronze holder supervising. I say technically because I've been finding that if they are allowed to fly their foamies unsupervised they get a lot more stick time and their flying with bigger models improves a lot. So I am currently trying to get the club rules changed to allow a quick test by a committee member to make sure these people can fly their foamy safely and let them get on with it. I reckon an electric model under 1kg fits the bill for this. They'll not be allowed to fly anything bigger than this till they get the bronze. They then continue with their training in the usual way with an instructor and a regular model, to get their bronze. I hope this means in future trainees won't get fed up waiting around for a flight and the learning process will be quicker. And I can't see that it's likely to compromise our safety standards at all. I think it fits in quite well with the BMFA's new requirement that a model weighing at least 1kg be used for the A test (I think that's right?). John.

Second the last two posts

Hi Clive,   I think the it only becomes a requirement to ask for a notam if there will be five or more models operating at the location at the same time.   John.

Engines, you've got to love them eh?   What plug are you using? OS engines like OS plugs (No8 or A3) which are slightly shorter than other plugs and quite hot. Other plugs stick out into the cylinder head and have the effect of changing the timing slightly. Something like a Firepower F7 for instance could make the engine kick back and be a pain to tune. If you haven't got an OS plug try putting an extra washer under the plug you've got.   The other thing that makes engines start backwards is if they're very wet (almost flooded). Try taking the plug out and disconnecting the fuel line then give it a quick burst with the electric starter. You might get a spray of fuel out the the plug hole. Put the plug and fuel line back on and tap it with the starter again. Once it's running leave the plug battery on for a minute or two and then give the thing a good rev to clear its tubes. Hopefully it'll keep going and give you chance to let it warm up properly and get the top end tuned.   If it's started eating plugs you've maybe got a bit of a previous blown plug coil battering about inside the cylinder. You'd need to take the head off and look for little bits of metal and clean them out.   Sorry if I'm teaching Granny to suck eggs here. You may have tried all this already. But you never know, might be useful?   John.

The trick with an air bleed screw is to screw it out till the hole is completely open then slip the point of a pin into the hole and screw the bleed screw back in till it just traps the pin. The idle should be not far off at that. Remember unscrewing the bleed screw makes the engine leaner at idle (the opposite of a twin needle carb) so if the hole is completely unobstructed the bottom end will be very lean. Better to err on the rich side and put up with a slight splutter in the pick up. And I'd agree with the previous poster that it's best to keep the top end a little rich as well.   The FP40 is no power house, but is very light for a 40 (not much heavier than some 25's). If you do change the engine you will get a lot more power and performance, but you might need to put some lead on the tail to preserve the handling. A 46 2 stroke works well, I've got a Thunder Tiger 46PRO in my Wot 4 and it goes very well indeed.

I got a nice pair of wrap around sunspecs from my local huntin' shootin' fishin' emporium for about six pounds. Sold as safety glasses for shooting. Good tint and keep the wind out of your eyes. They also do the yellow 'contrast enhancers' as the shooting people like them. You might also see pink tinted ones for dull days. I think you can get similar things from B&Q  or Homebase sold as straight safety glasses. Cheap as chips and quality guaranteed as they have to be up to a certain standard and kitemarked. No use for prescription wearers, sorry, but perfect for cheapskates like me.   John.

Thanks Pete,   Been reading this forum for ages, only the second time I felt the urge to post. Probably be easier now I've broken the ice.   John.