Nigel R

Good effort with the stone, must be 100kg or over, they are extraordinarily tricky to lift with that shape, I could never get to grips (sorry) with the technique for the first part of the lift. I still keep up the gym lifting - mostly focussed on the regular powerlifting bar lifts. Managed to get a 550kg total in my late 30s. Sadly I think trying to repeat that would probably bury me these days.

Snap! Although the arrival of kids somewhat put a stop to the skiing holidays... 🙃

Snakes are perfectly strong enough for a sport model like a wot4. I use them as first choice for elevator. I fly 10cc size airframes. Closed loop often my choices for rudder.

Airplane mode disables all RF output from the phone.

Similar but no - smaller barrel on the 36/39. 40/46/53 were all the same (I think). The needle was common across the range though.

Fair points Pete.

Depends on your hinge type. I like polyprop hinges. They're essentially indestructible when compared to balsa. I use canopy glue for these. Having tested a few hinges to destruction, I can confirm it does not need pinning. The balsa will be snapped before the hinge comes unglued. In one test I ended up ripping the hinge along the hinge line, although the balsa was plenty destroyed by that time. The trick is to make sure the slot is pre-filled with glue, so that it actually gets all over the hinge leaf, instead of just a little tiny bit by the edge. Again, neat trick (not mine, I read it somewhere) - use a 2" length of plastic straw, fill it with some glue, and use that to "syringe" the glue into the slot.

M3.5 for this age I thought? Could be wrong though. Might be M3.

No, in a word. Mobile phones use different frequencies to RC gear. On that basis the mobile is less likely to interfere than someone else standing next to you with a TX. You can discount swamping, mobile phones have low transmit power. Comparable scale to RC TX. The throttle going to full power sounds far too specific. If nothing else went wrong, and you didn't lose control of the rest of the surfaces, and it didn't go to failsafe because you already verified failsafe closed the throttle.

Interesting enough. But. Maybe the thread title should be "FrSky Servo chatter"? Or "FrSky poor interference rejection"? Or "FrSky introduces noise to analogue outputs"? Or perhaps "fingers near servo stops chattering"?

Heat can be used to straighten out a warped bit of balsa - Heat, then clamping, opposite to the warp. Never really had a problem during covering though - maybe worth trying old style sanding sealer then dope instead of water based poly?

Another Nutball fan here - welcome aboard 🙂

There is the free online version of Word, too... https://www.microsoft.com/en-gb/microsoft-365/free-office-online-for-the-web Not used it myself. But. It exists.

Intermittent faults are the bane of an engineers life... just as true on the development side of things as it is repair...

Agreed. David, your CAD & 3d printing skills are making me green with envy. Nice hound too. Although he should be facing the camera 😄

Agreed, whilst the Acro Wot is popular it does have a few "characteristics" due to the coupling. The spiral bunt caught me on the few occasions I've had a go with a clubmates foamie.

Covering iron would be better if you have one. But if it's just a bit slack, that's probably not it. I was thinking of edges coming unstuck, that kind of thing. Stall strip can be quite temporary, you could attach something with some covering film to try it out for a flight or two.

If it's on the very edge of stalling out then a slight imbalance could tip things one way rather than the other. Can't see a minor difference like you report being the real root of the problem though. Seems like a lot has now been checked over. Couple of further thoughts: has there been any previous crash damage / repair? (possibly the structure is weaker on one side after repairs) covering - no loose stuff? maybe a last resort - you could try adding a stall strip to the root of the LE, this could (at least) get you a consistent "dead ahead" stall behaviour.

No inertia in a foamie, as noted, probably best "flying" it round with a bit of throttle to get some air moving over the rudder. Would also check the thrustline. You might find it is a bit out and correcting it allows you to get the trim back in shape.

Non pumped surpass engines are not uncommon on eBay... Just keep an eye out for a 91. It'll probably cost less than os seem to charge for a while brand new carb, even if they bothered selling them for older engines.

65mg should be ok, I'd have thought.

I would double check incidences including thrust line and then trim the CG with the usual aerobatic checks, at the very least with the dive test. Another point, this is an airframe with really big surfaces; what servos are you using? They need to be up to the job of holding those large surfaces in check. Simon and Martin's lists are excellent suggestions too. Lots of sharp changes of direction evident in this manufacturer's video, with no evidence of wing drop - your airframe should be "fixable":

Precision Aerobatics made good airframes. The stall should be quick, clean, but straight ahead in this kind of shindig. Perhaps it is a bit of a Friday afternoon one, or it has warped a little with time. Well worth checking out that everything is put together accurately. A Parachute involves vertical dive, hard up, then carry on downward in a deep stall. Are you doing that, or just pulling hard up to recover from a dive into straight & level? If it's the second, with this kind of airframe you may have to "fly" it through the recovery.

Surely, surely, if the prop was balanced, there would be no vibration? At least from the prop. Perhaps something else let go? I'm with Dickw. I have many IC props. Would use them any time on an electric. They're just props that exceed the required safety margin by more than their electric counterparts. I can't materially see them being less efficient, maybe someone can explain why that would be the case?

Not sure how the UK will benefit?