Chris Anthony

Indeed, the plane's behaviour after the initial perceived "loss of control", now that I think about it more, was very similar to when I was deliberately inducing stalls and trying to induce spins in the previous few flights (I am probably using the terms "stall" and "spin" loosely here, maybe inaccurately, but my point is, I agree now that the plane may not have been operating in it's "aerodynamic safe zone". What still has me puzzled though, is how the stall actually started. I suppose this is something that you will have to take my word on, but the initial pitch acceleration I witnessed just seemed too great to have been caused by gravity (due to loss of lift) alone. It really did seem like the pitching was induced by an involuntary control input. The aircraft still maintained its forward speed throughout the whole ordeal, with no noticeable velocity vector in any other direction - i.e. it wasn't "slipping" through the air. The aircraft seemed to follow a very standard path curvature, and maintained a very normal slip angle during the initial downwards pitching and descent. This is contrary to the behaviour of aircraft I have seen that are stalled, where aircraft may pitch or they may not, but also, the new speed will not be just forwards any more, the total velocity vector will be at some angle to the longitudinal axis of the plane (this is the definition of angle of attack, right?), and as you say, this angle is likely to be greater than the wings can cope with, hence the reason they are stalled. Yes I had elevator input at the time, but it was minimal and my inputs were as smooth as ever. Even if a large enough angle of attack (which as I say, wasn't visibly present) had been created, I can not see, think or understand how. As I'm sure you can imagine, this trainer would float along at what looked like a good 10-15 degrees AoA more than comfortably at the right speed, and that was very noticeable! Unless, and this is something I need to confirm, airflow in that patch of the sky suddenly changed direction, due to turbulence or thermals or something else? My experience again limits me here, and I'll have to ask club members about our particular field regarding this. Or maybe the cause of the initial pitching was different, perhaps it was elastic band stretch as previously mentioned, but then bad corrective input from me lead to a stall, which caused the further described loss of control. As already said, this is the horrible problem of having to rely on a poor memory with no objective data to hand! Even better would have been having an experienced hand and eye next to me at the time. Back to speculation.. By the way, BEB the way you described the elevator as an angle of attack controller is fantastic, I will forever fly my planes differently with this thought in mind. I do want to talk more about stalling, speed and angle of attack a bit though if you don't mind, to clarify a few things. I know you say that speed, or lack of, is not the direct cause of a stall, it is angle of attack. I understand this principle, now a lot greater than before. I would like to test some ideas with you though. These are just thoughts I have come up with, so if there is common aerodynamic knowledge that I am either ignoring or patronisingly repeating in my thoughts then please let me know: There is a reason that most pilots attribute air speed to causes of stall, it is because for each individual aircraft, air speed and achievable angle of attack are directly linked, coupled, if you will. As you say, the cause of a stall is excess angle of attack. But there is also certainly an observable correlation between stalling and air speed; usually, it is fair to say, most planes/pilots seem to stall at low airspeeds. This therefore implies that there is also a coupling between airspeed and angle of attack. If I were to say that at lower airspeeds for most aircraft, a higher angle of attack is achievable than at higher air speeds, would you agree? As I see it, this simply comes down to horizontal stabiliser design and elevator control surface design, and perhaps their distance from the CoG/CoL in each individual aircraft's case. Consider my high-wing trainer, for example; the stabilising moment created by the H-S is going to be much greater than the maximum pitching moment that can be created by the elevator control surface at a high air speed, and so will prevent a large angle of attack from being achievable, even at full elevator. And as an example of the opposite, I would comment on the planes you mentioned that experienced pilots have managed to stall at high air speeds. I presume, that these had large elevator control surfaces relative to H-S size, perhaps with "shorter tail lengths" too, which means that large AoA attitudes are actually achievable even if full elevator is applied at much higher air speeds, right? Point being, given that stalling potential is based on aircraft architecture, and given my model type, don't you think it unlikely that I could have stalled so long as I had maintained a normal air speed, (unless something exceptional occurred, like I flying into "bad air", because the aircraft design ensures that a large AoA can never result from this?

Thanks Rich, yes it is new model time now for sure! At the moment I am positive that there was power to the RX, because I got no "power loss" warning until after the aircraft was in the ground, verifying that the power warning system was functioning at least! I am interested though, how is it possible for an RX switch to switch itself during flight? Is this a common problem for inexperienced pilots/builders? Again, I don't consider this a possible cause in my case, I just ask out of curiosity, and can't imagine how a switch facing outside of the aircraft can be moved by airflow/vibration alone. I had only reset the antenna in this case because I had to take the RX out of the plane the afternoon before to reach the fail-safe button, as I set the fail-safes for the first time just before the fateful flight. Dave, thanks for the practical band tips and antenna orientation advice. I still haven't ruled out incorrect antenna orientation as a cause, there is just the lack of a "signal loss" warning needs to be explained. I still feel that this warning should have been present if this was the cause of the crash. I will remember your idea on sticking an antenna outside of the fuse though. I have also decided to remove any elevator input for my future fail-safe settings, based on this experience and subsequent advice. BEB, thanks for that very strong clarification. I have heard this clarification made a few times before from varying sources, but had never focussed too much on the details. I used to feel happy and satisfied that I could recognise a stall in progress, and knew how to correct for it, and that that was enough, without having to disseminate what caused the stall; a lack of speed, or too great an angle of attack, etc. But I started getting a horrible feeling in my stomach reading what you have said and how it seems to correlate with what happened the more and more I think about it. I would like to make it clear now that, especially after your last description, I'm starting to consider a stall very possible. Especially when I received no "loss of signal" warning from my TX. (Please see more below). Edited By Chris Anthony on 29/04/2014 13:01:35

Steve, thanks for your comment, I've only just seen it. I know exactly what you describe, and I had actually experienced this effect in parts of my flights this evening, and also in a few other flights during the past few weeks. I first encountered this effect (where it scared the pants off me) during the second or third session I ever had with a real, wooden, heavy IC aircraft (this very same Seagull, RIP). On that evening, I got to the field and realised I had forgotten the ~16 or so standard elastic bands that came with the model, so I decided to use the ones from my small Foam-E Ares Gamma trainer (6 weak brown bands only), which is about 1/4 the mass of the Seagull. I then quickly learnt about this effect, and noticed it when applying above 30% elevator rather quickly, at near full speed, usually to instigate a climb; there would be a small delay in pitch response, but then a dramatic overshoot and huge pitch rate gain, where the plane would turn towards vertical much faster than I was used to! This usually resulted in a noticeable loss in forward speed too.. As said, this even happened a few times tonight, which I put down to my elastic bands being a month or so old, and having been damp with nitro fuel for that whole time, which I feel may have caused the effective clamping spring rate of the bands to reduce. But, whilst I think your diagnosis is sound, I don't think this was the actual cause/or only cause responsible for the crash tonight. I think this because firstly, the pitching occurred without my asking for any up-elevator. The "elastic band effect" only seems to delay and accelerate any pitch motion initially instigated by the pilot, and my downward-elevator control position should have ensured that no air got between the wing and the fuselage. But I also know that this may have easily occurred regardless of what I was doing with the elevator control. Maybe the wind changed, or something like that. Maybe the wing did indeed leave it's mating face with the fuse, and cause an up-elevator pitching effect. But, in my opinion, this was just not enough to explain the sustained 10 seconds of lack of control that followed the initial instigation that I described. Maybe, just maybe, the elastic bands did cause the initial downward pitching of the model, but this must have been followed by some other coincidental failure almost immediately after, causing the final demise of the model. The latter failure being enough to make the former failure seem almost meaningless anyway. Edited By Chris Anthony on 29/04/2014 01:48:11

Thanks John. Indeed a right shame. And as you say, it's something I could come to terms with, accept, and overcome a lot quicker if I knew the cause! If it was pilot error and I knew what I did wrong, I could evaluate and train myself to not repeat, and improve. But as I do not know what exactly I did wrong, I am so very worried that it will be repeated with my next model! Martin, the "low signal" warning usually occurs when signal is weak but not completely lost. So you still have control over the model when you receive the warning, and enough time to turn the model around and fly it back towards you. What happened tonight was different though, I just lost control without the grey-area warning. If anything, I would have expected the "loss of signal/telemetry lost" warning to have occurred in the air as soon as my fail-safe settings became active, but alas, this did not happen either. I decided to set the full-up elevator fail-safe so that should I lose control over the aircraft, it would pitch up, stall, pitch down, speed up, pitch up, stall etc all the way to the ground without ever exceeding a certain, nominally low speed during these cycles, to minimise crash damage upon contact with the ground, regardless of altitiude. What you say about straying into dangerous airspace is definitely a valid consideration, but I figure that with zero engine thrust, full elevator would only give 10-20m of futher altitiude gain before descent would occur due to the first stall; and from there, only further descent would be seen. Of course, I had not considered the case of loss of signal during inverted flight! .. Anyway, after viewing the wreckage of my model from a not-so-great height, you may be pleased to know that I now consider that this particular elevator fail-safe setting may have been a futile effort to save a model, which would probably be a write-off in any case even from that height. Yes my FrSKY RX does have 2 antenna, and it pains me to admit that they may not have been at 90 degrees to one another when I set the plane up for my flights this evening. I have a horrible feeling that I set them both pointing forward, just parallel to each other, pointing forward down the longitudinal axis of the plane (towards the prop), offset around 80mm from each other (the width of the fuselage). To expand, it pains me to say this most because I found out tonight, before the final flight, the reason that the antenna must be 90 degrees from each other. But, I do not want people to focus completely on this though, and to keep an open mind as to any other possible causes to the failure. If this was the cause, then firstly, why did this only cause a problem during inverted flight? The plane had been at that height, dustance and heading relative to me lots of times at that site before, why would it being inverted make a difference? And also, there is still the fact that there was effectively a loss of signal, and a TX warning should have been present, even in this case, right? This is again where my inexperience shows, is it possible to lose signal/control without this being registered by a telemetry TX as a loss of signal? BEB, as for stalling inverted, I can't think why this wouldn't be possible, but again, I am too inexperienced to recognise this. I actually remember thinking, at some point during the descent, that a very strong wind had caught me out whilst I was inverted. But I did not figure this to be an actual cause of the crash because I could not hear/feel any wind on the ground myself, nor see any effects of it on the hedges less than 50m from the crash site even many seconds after the crash occurred. I did not figure that any kind of stall had occurred because I perceived the speed of the aircraft across the ground beneath it to still be great enough to maintain lift/at least some amount of control force from the control surfaces that I was stimulating. I am of course open to correction on this, but as you point out, the lack of more knowledge makes only speculation possible

I was at the club field tonight flying my Seagull Jumper 25 around (with FrSKY Taranis X9D TX and FrSKY D8R-II Plus RX) on about my 3rd tank of fuel. I was flying the plane inverted, on this occasion I had been doing so for about 30 secs - 1 minute. The plane was at around 75-100m height, and around 200m away from me (just the other side of the landing patch). My position relative to the plane at that point was "8 o clock high" if "sitting in the cockpit" (as it was inverted). So it the plane was flying away from me at around that kind of angle, if you can picture it. It was flying straight and level, but inverted, with a small amount of down-elevator (25%) on my TX stick, 80% throttle, minimal aileron movement and no rudder. Suddenly, the plane seems to hike on a load of up-elevator and pitches towards the ground. I had not made any elevator input to cause this. I tried adding down-elevator to correct this, but nothing seemed to happen. The plane dropped to around 25ft of height and also had a slight but constant right roll as it began descending. By the time my first involuntary immelmann was complete, with the fuse parallel with the ground, the right wing was completely dropped. At this point I THINK I remember the engine being down to idle, I don't remember touching the throttle but I may have. With the aircraft being unresponsive to any aileron or elevator input, it continued to move through this orientation in a sickening right-hand, downward spiral which ended seconds later with the plane nose-diving into the ground. Now, the first problem I have here is that I don't remember exactly what I was doing with the controls in the mere 10 seconds that this all happened in. But most people I'm sure are aware of the feeling you get when your control movements do not result in aircraft response as you would expect, even if you become confused with orientation for a second, which I wasn't. You know when you have lost control in some form, even if you can't quanify the loss. I feel sure that I would admit to any pilot error that I was conscious of. I have experienced the feeling of adding in incorrect elevator when inverted and only realising seconds later. This is not what happened. The pitching that started tonight all came when I did not move the elevator controls at all, and the aircraft did not respond to any further inputs, that I could redognise, from the right TX stick from that point on until crash. I am also not 100% sure on what the engine was doing. I THINK it was idling as the plane hit the ground, but it may have not changed speed at all. This is important because of what my fail-safe settings are; 0 throttle, and full up elevator (no aileron or rudder). More on this below. Some more info; my Taranis TX and RX telemetry give 2 audible warnings that I am familiar with and have tested. One tells me when the RX is near it's range limit. This is at around 4 times the distance from me that the plane was at today. The other warning tells me when the RX cannot be found at all ("telemetry lost", which only ever occurs when I switch the RX off after landing the plane. It was only once the plane had crashed that I heard the "telemetry lost" warning from the TX (battery presumably became disconnected upon impact). I was not warned that signal between the RX and TX had been lost when the initial control loss happened in the air. This flight was different tonight for one - maybe 2 reasons. The second, less credible reason is that tonight was the first time for me flying on my own at the club field. I have just joined as a member, and have flown once before in experienced company. I do not know if there has ever been cases of interference from nearby features or anything.. this is something I am enquiring about with the guys there. The first, and main reason that the flight tonight is different though, is because it was my first flight with fail-safe settings actually set. Essentially, from what I can interpret/remember, from the moment I lost control to the moment the plane crashed, I had full up elevator and, I think, zero throttle - my new failsafe settings (I believe the rolling to the right was just a product of roll speed/inertia I had at the moment that control was lost - and the loss of airspeed just increased this roll effect). TL;DR - I find it a horrible coincidence that the plane was acting like the fail-safe settings suddenly became active, but I had no warning for loss of signal from the TX, and I was well within normal operating range. Could anyone think of an explanation for this? I have basically written off being able gain any insight from the wreckage because everything (mainly servo positions) changed upon impact. I appreciate how hard this may be to comment on with no data, no pictures, no video, no audio, no clues from the aftermath and a sketchy description from a biased and forgetful witness. But if anyone could come up with any suggestions as to what might have happened I'd be very grateful. In tragic coincidence, it was just this morning that I ordered my next plane, after feeling competent enough to sack off the Jumper. Indeed, flying it tonight I felt very confident, almost bored with it, drawing the line at trying to get it to flat-spin. I did not think I would be forced to move on from it so quickly though, and am now worried that I may prepare my next plane in the same way that will cause a similar failure. No sympathy required! But all thoughts will be appreciated. Thanks, Chris

cymaz and Dave I've only just noticed your comments sorry. cymaz, the fuse is just covered in seemingly standard vinyl wrap, no silver or carbon fibre tape that I've noticed. Dave. They shouldn't buzz when they aren't doing any work. By the way chaps, this plane crashed tonight due to some kind of radio failure. I'm just about to write up what happened in a seperate post, I'd love to hear your inputs. Cheers, Chris

Great answer, especially for 3 and 4. It makes perfect sense. Thanks Bob.

Both? The new one first, so if it doesn't go to plan, you can fall back onto what you know and not feel so bad.

Hi guys, Sometimes depending on RX orientation in the plane, my throttle and aileron servos (closest servos to RX) will make a buzzing. Like when something is trying to move them and they are resisting. This only happens when the RX is next to them, with RX switched on AND TX switched on. If I wiggle the antennas of the RX about in this case, or sometimes just touching an antenna, the noise will stop. But whenever I think they are in a position which eradicates the noise, as soon as I let go of them, the noise returns. TX-Servo control doesn't seem to be impaired, and range doesn't seem to be affected but my questions are: 1. What is the cause of this servo noise? 2. What is the worst-case scenario that could result from this noise/it's cause? 3. Why do the RX antenna's need to be 90 degrees apart from each other? 4. What is the worst-case scenario that could result from not ensuring 3. above is met? 3 and 4 I feel might be related, but to be clear, I do make sure the RX antenna's are always 90 degrees apart. I just don't know why this is recommended. I'd be grateful if anyone could advise. Thanks, Chris

Mark, BEB, thanks for the technical descriptions - that's the kind of stuff I love to read. I can picture exactly what you describe BEB and have been guilty of flaring too early, and too late, and am familiar with the effects! Fortunately none of those situatons resulted in too much damage, worst being a few nose-overs and prop-strike-stalls. And what you say about keeping the speed up for the landings makes sense to me too, this is something I'll keep in mind. Graham, I've not yet had the chance to experiment with exponential rates. This is also something I'll bear in mind. As I understand it, expo can give you large throws when desired, at the extremities of your TX stick movement, but with smaller adjustments available towards centre-stick. It essentially provides a mix of high and low rates, would you say that that description is accurate? Or is there more to it. If this is accurate, at the moment, having high and low rates changeable at the flick of a switch seems to be good enough; position 1 for the funky aero stuff, position 2 for landings/practising.. John and John, thanks also for giving me some confidence. Edited By Chris Anthony on 27/04/2014 22:31:00

Thanks cymaz and Mark, I think I'll go for an SC 2-stroke, I have an SC25 in my current plane. I'll see what my LMS has on the shelf. Gurth, it is late but not too late. Whilst I feel pretty set on my decision, I am still able to consider advice against it, especially when worded so strongly. Forgive my ignorance, what exactly does "aim for a roller, rather than a cool 3-pointer mean"? And when you say "it needs flying all the way onto the ground", can you expand on this a little? Thanks, Chris

Thanks chaps, it's good to hear that the ARTF will be fine. So as soon as I get paid at midnight tonight I'll be ordering a Ripmax Acrowot Mk2 ARTF. I have a few more questions related to this plane: 1. Can anyone advise a decent engine manufacturer/model for me? I am planning on running a .55 2-stroke in it, or the highest power rating advisable. My thinking is that I don't always need to use full power, especially when starting out, but it would be nice to have the power and speed available for when I do become confident. 2. Can anyone tell me roughly what kind of prop I would need to make this flyable? Perhaps it would be worth me getting 2 props, one for slower flying/learning, then one for faster flying, if this is something that is ever done (equivalent to rate changes)? 3. The Ripmax write-up for the plane states that it needs 5 servos. I can only imagine that this is because there is a servo for each aileron, can someone confirm? I presume further that this is the norm for all mid-wing stuff because the wings are separate? 4. Any final advice on flying the thing for the first time? Are there any behaviours it may have that are likely to catch me out based on my current high-winger experience? Currently all I can think of is to use low rates, pick a fine day, and once taken off, do a few low-speed practice approaches to assess it's behaviour before actually attempting the landing! Thanks, Chris

Guys, sorry for not contributing to the original question. Vecchio, I was just wondering if that yellow object on your desk in the picture is some kind of mini-lathe? If so, that's fantastic! Where did you get it? Chris

John Melia I completely agree. My disc is Phoenix 4 and I installed the game on a new computer. Without updating to V5 straight away, I had a play on V4 again after hours of playing on V5. The difference is very noticeable! I was flying the low-wing trainer plane and it was a lot more unstable in roll on V4 as soon as anything below 80% throttle is used. And so the problem is, now I don't know what's real any more!

Great news, I'll start looking into a low-winger. Ron, you've brought up another concern of mine. I've read into WOT's quite a bit, what exactly is wrong with the ARTF versions? I've heard the same things said about the Acro Wot, Wot 4, and Wot Trainer. Are the differences enough to put me off? I'm really not keen on spending all the extra hours building a plane from that kind of level at the moment, I'd rather be out there flying them. Edited By Chris Anthony on 21/04/2014 22:16:27

Yes, to power your radio gear (receiver, and servos via the receiver).

It sounds like a sweet project to me. In line with what BEB said, splitting this into 2 requirements gives you 2 levels of complexity in the work ahead: 1. Flight with the fans vertical only; this is just mimicking a quadcopter but with EDF's instead of props and as Chris said, there is nothing special about it really. 2. Transitional flight; this is where things would get really interesting. Some initial things you need to do will include: - Establish what axes the fan housings will pivot around to vector thrust. Currently your sketch implies only one axis (front and rear axes parallel) but your text mentions two? - What range of angles will the fan housings move to in order to vector their thrust? - Will the body design produce enough lift to support the aircraft with fans at their angle-furthest-from-vertical? - How does this lift vary with changing fan thrust, thrust angle, overall airspeed? - At largest thrust vector angle, will your fans add pitch moments to the aircraft for control? If so, how? Figure a control strategy. If not, you will also require some body control surfaces. - At largest thrust vector angle, will your fans add yaw moments to the aircraft for control? If so, how? Figure a control strategy. If not, you will also require some body control surfaces. - At largest thrust vector angle, will your fans add roll moments to the aircraft for control? If so, how? Figure a control strategy. If not, you will also require some body control surfaces. First, I am assuming (from your descriptions and my poor memory of Avatar) that you want the fan housings to pivot on their lateral axes, and to move a maximum of 90 degrees forwards, to make them act like plane engines for horizontal flight (and maybe some degrees backwards too). This would be essentially like a V22 Osprey. Correct me if I am wrong in this assumption. If this is close to being the case, having the fans move fully forward in transitional flight (90 degrees from vertical) will limit the pitch/roll control of the body you can program into the fans by mere independent fan speed changes alone. Yaw control might be covered enough by fan speed changes, but unless you somehow couple yaw motions with roll, this won't be enough to maintain control. Then you still need to work out a method of controlling pitch. This I believe is the reason that a V22 Osprey still has a tail-plane and ailerons on it's "wings". If you can't add your own control surfaces to the body for this transitional flight, you will need to limit the thrust vector angle to less than 90 degrees. Even then, the control strategy required would be very interesting! As for what your teacher said; sometimes people will say things like that to bring you down. Sometimes people underestimate your level of determination or skill. Sometimes people are just plain wrong. Don't let it sway you, strive to find out for yourself. Even if you fail, you'll learn a hell of a lot more than if you didn't bother. As for what your girlfriend said, what does she know about the subject that you don't?! Hope you give this project a good crack anyway, I'd love to see your results, especially if they are positive. Chris

Well guys, thanks for the tips. So, low wing trainers are generally less stable, as in they do not return to level flight on their own as much as high-wingers. I need to ask: 1. Is this just in roll? What about pitch/yaw? 2. Why are low-wingers more like this? Is it just because low-wingers are likely to have less dihedral? Or is there some other physics behind it. Gurth, I've picked up on what you say about "responsiveness". Response, simply, is modified by rates, no? So if I flew a WOT4 on low rates, so that responses were similar to those of my high-wing trainer, what other differences would I notice with that aircraft? I am testing this subject as I have heard many people in the past say that moving to a low-wing plane should be done cautiously. Your experience is good to hear though Ian, it's given me more confidence to move on. Thanks, Chris

Hi all, Can someone explain to me what is different in the performance of a low-wing plane to a high-wing? I'm getting competent with my high-wing, and considering moving onto my first low-wing (trainer perhaps). It will be the stepping stone between either a Spitfire or my first 3D-capable model. Thanks, Chris

Online now for an hour or so, modelflying/forum. On a 3D map but free flight at the moment.

I've got a session on the go tonight for a bit, same format as yesterday (see above) but is not mandatory of course modelflying/forum

I hope I wasn't too much of a bad influence on you Rich Those sessions are great fun, I'm in for the next one!

Thanks for the cleaning tips guys, I'll try some baby wipes first I think. On a similar note, how do the elastic wing bands cope being exposed to the fuel? Should I be replacing these at certain intervals due to them being coated in the stuff? They are very hard to clean and seem to remain contaminated permanently from their first flight on the aircraft onwards. So far these ones have lasted a week at least. And Peter thanks for the tuning tip. Low speed adjustment makes sense, as I haven't touched that needle yet. If it's the one I think it is, it is pointing straight at the head, so I can't get a driver to it unless I move the carb with the engine stopped. Is this right?! Also, that high speed needle is a tad close to the prop! Chris Barlow, and everyone else, any tips on fuel line set up to cope with sustained inverted flying? I've tried a few inverted push overs and a few times it has cut out, had to dead-stick land it (luckily I'd got a bit used to it by then!).

Chris, thanks for the info (and the plug!). Bob, yes as you mentioned, I get RX battery voltage readings from the TX as standard with the D8R. Yes some of that info did get confusing towards the end, but I'll pick it up in time when it starts to become more relevant. On the whole I'm not too worried about telemetry at the moment but it's nice to know what my options are.. I'm not yet even sure what the data would be useful for, other than it being used as "black box" clues in crash scenarios (?). Well I'm getting well into the programming, it's good fun! But very time consuming. So far I'm doing Stick and Mix programming for my 3 models, and other general model set-ups. Something I plan for my Phoenix 742 glider is introducing some element of "flap" function on the flick of a switch, as there are independent servos for each aileron. Not sure exactly how I'll do it yet but it will be one of my first little projects with this TX. I'm not sure how long to prolong this thread before it ends up being fully technical, and no longer "beginner" subject material but here is my first observation whilst doing all this programming: I plan to use a common (my only) TX and RX for 3 models. Setting Stick and Mix parameters is all well and good, but this method is fully reliant on me plugging in the same servos into the same slots on the RX every time I swap the RX between models. Is this correct? I haven't yet come across a function that can determine which servo is which, no matter where it is plugged in on the RX. I suppose there is nothing to uniquely identify servos on a model, so this is always likely to be a problem, would you all agree? This wasn't such a problem with my old park fly RX, as the channels were labelled R-A-T-E, not numerically. As far as I can tell, the only way around this now is to record a key for channel numbers govern which control surface and keep this common when setting up all 3 models.

Chris, well spotted! My bad, it's a D8R-II PLUS that I have bought. I copied the wrong code from my eBay watch list haha. As you can tell, the RX names are just random numbers to me at the moment! That is good to know any how. I'll remember that for when I get round to looking at Parkzones with more seriousness. Thanks