Jon H

Then then decide to fit a mahoosive engine and make so little effort to fit it neatly in the cowl i wonder if they actually just left the cowl on when fitting the engine and just cut a hole big enough to fit it without taking it off.

I would rather fly a model which is slightly under powered than one that is over powered. Underpowered is easy to deal with, but there comes a point with an over powered model where you simply cant do anything with it as the slightest touch of the throttle has it heading for the sound barrier. 70-75 inch warbirds should, in my view, be between 12 and 16lbs and need between a 100 and 150 class of power plant. My Pica P40 was 72 inch and 15.5lbs but my 155 flew it with ease. In fact once the nose dropped below the horizon gravity did all the work and i was throttled well back to keep the speed in check. which was a win as it saved fuel! A friends YT P51 was about the same and a 150 flew it fine. My restored ugly mustang is about the same but my 160 inline is, on the face of it, a bit wimpy. However, i noticed that vertical performance was fine, its just slow. No matter what i do it just does the same speed all the time. The wing on it is very thick and clearly very draggy. It seems to hit a top speed it cant get past without a full throttle dive. Even then it is not fast so its clearly a peculiarity of the model.

As he has never flown it how does he know? Also its not his problem after he sells it! I think i have told this story before, but its lost so ill tell it again. Some years ago a club mate had a Hangar 9 60 size F6f hellcat with a 90 4 stroke in it. It whizzed about alright, but he was struggling with it and asked my help. His complaint was a lack of power, and what should he do about it. New prop? Bigger engine? etc. So i took it for a fly and after a lap of the patch i said it didnt seem short of power. His response was 'but i cant even loop it, theres no power at all'. He was then shocked when i did a loop about 300ft in diameter. He was used to light sport models which respond to a 'bank and yank' flying style. This relative brick did not and his aggressive style did nothing but scrub speed by cranking large angles of attack on the wing. With the speed scrubbed off he lost vertical, which meant he lost potential energy on the way down, which he then recovered from hard and scrubbed more of his energy away. He was just too ham fisted with it. Preservation of energy is very important flying warbirds and its a skill many never seem to learn. Its a shame as a warbird flown with energy management in mind immediately looks more scale as its exactly what they do in the full size. I have also flown my flying test bench (85 inch brick of a model of about 20lbs) on everything from 120 to 450 glow and it was aerobatic on all of them. Sure it took a while to takeoff using the 120, but once up it was still perfectly able to loop. Still, if you arent sure then give it a miss by all means.

i never work out my wing loadings so i have no idea. 13lbs for a 72 inch warbird isnt bad though and it will fly without doubt. You might lack a little grunt in the vertical, but it will loop with ease. There's a video on youtube of one with an fg20 saito and it looks like it goes alright. Another with a saito 150 which is very quick. The only thing to watch is the supplied spinner as they have been known to explode, so you may want to source an alternative.

it will be fine if its not too heavy. And you can ignore most seagull engine recommendations as they really over do it. They recommend a 120 for their gipsy moth when they have flown successfully on engines far smaller.

If you are confused by a problem and its repeatable do a video and post it here. Its likely we can then translate the engine speak into something useful. Just remember to keep the camera out of the prop wash as wind noise is not a useful diagnostic tool!

Agreed Tach's are handy for comparing props, and getting a general idea of engine performance but they are not an every day use item.

GG isnt wrong here, but on running in i would suggest you ask yourself a question. Do you have an ounce of mechanical sympathy and a brain in your head? Most likely the answer will be yes, and if so you can usually amend the running in instructions provided to get the job done quicker and with less faff. The reason is there is that one guy who will add all sorts of things to some witches brew of trash fuel before firing up his new engine on a prop either miles too small or miles too large, and will then try and wring the life out of it the moment the thing kicks over. As a result, and to protect themselves from a grumpy warranty claim manufacturers tend to be very cautious with their run in instructions. if you arent that guy, you can follow a simple procedure which suits more or less every engine on the market be they 2 or 4 stroke, ABC, Ringed, whatever. No1. use a good fuel. Cant be bothered to argue about specific brands today, but generally a 5% nitro 15% synthetic oil fuel from a reputable manufacturer will work. No2. use the right prop and plug. The blurb with the engine will probably be a guide here so... If the instructions are missing, work out the standard prop for your engine (say 11x6 for a 46 2 stroke, 12x6 for a 52 4 stroke, 15x8 for a 120 4 stroke) and knock one inch off diameter to give a lighter load and get the revs up a bit. I go with os F plugs for 4 strokes and OS no8 for 2 strokes. Personally not a fan of the enya 3, but if you want to try it then fair enough. Just remember your glow clip might not fit it. No3. Some engines (ASP for sure) are pretty dry when they arrive from the factory. There is no harm in adding some oil to the thing ahead of time, especially on a 4 stroke. Whip off the rocker cover, a little dab on the rockers. Whip off the cam cover, a little in the crankcase. 2 stroke oil is great for this and there is no need to go mad. 2 strokes just need a little down the carby. Wiggle the engine about to spread the oil round, and leave it to drain if you think you over did it. No4. mount your engine to the bench/model with respect to tank height etc. No5. Start the engine with a rich but not slobbering rich setting on the needles. I would say 2 turns max. Get the glow off and open it up to about half throttle. Run for about 2 minutes and make sure you can feel the head warming up, especially for an ABC 2 stroke. Note that some ABC 2 stroke engines are mega tight when new. If so, get out the heat gun and warm up the head so its north of 60'c before you try and start it. You can even heat it up to 100'c if you want, you wont harm anything. No6. Full power, and very rapidly tune for approximately 90% of peak tune. This is a very rough and quick setting, dont loose sleep over it. Run 10 seconds and throttle back. No7. Tune the slow run so its not the absolute trash setting it came with. I recently test ran a brand new saito 82 and leaned the slow run nearly 3 full turns in the end so dont be shy. No8. Run with this tuning for about 5 minutes or so with varied throttle use right up and down the range. A few 5-10 second blasts at full power between periods of half and idle throttle. Some rapid accelerations from idle to full power are good too. No9. Once the time is up or you are bored pinch the fuel line to stop the engine. Allow to cool to stone cold. No10. Start the engine, tune for peak on both needles and go fly. Trundle around mirroring what you did on the ground with short bursts at full power. A simple turn around aerobatic routine is great as you use full power on the way up, near idle on the way down, half throttle in the middle, and then the same again. Essentially, just dont thrash it to within and inch of its life. 5-10 minutes of that, land, allow to cool before you go again. No11. After about an hour of running (4-6 flights) you can consider the engine run in enough to go to your flying prop and do your final tuning adjustments to suit. After that i recommend you peak the main needle at the start of each new flying day. Just open it so its clearly rich, lean off to peak, past peak, back to peak....hold for 5 seconds...fly. They should note its not just me saying this. Its in the OS manuals, PAW recommend the same. This information has been recommended by manufacturers for over 50 years and i cant understand why it seems to be such a shock. But, if the plane is inverted the engine will run slightly rich...so no big deal. if the tank is mounted too high rolling inverted will cause the engine to run lean and possibly cause it to stop. Its all related to the pressure differential between the carb and the fuel and gravity is a component in this. If gravity is assisting, so increasing fuel pressure, you close the needle to compensate. That's great until gravity starts resisting you and you have nearly 20m/s^2 change in acceleration just due to gravity. With the needle closed and a big change loss in fuel pressure the engine will run lean. I think its often forgotten that fuel is not sucked into the engine but instead pushed out of the tank. Atmospheric pressure (or exhaust pressure in the tank) is greater than the reduced pressure in the carb during induction so the atmosphere/exhaust pushes fuel out of the tank when the pressure in the carb drops. The problem is, gravity is stronger than both. If the tank is set as i recommend, gravity is always against us and the needle is set accordingly. As fuel is used the gravitational effect increases slightly, but only by a small amount derived from of the mass of the fuel in the fuel line and the head change in question. Say 50mm head change on a medium size model fuel tank and the weight of fuel in 4 inches of 3/32 id fuel line? This is all within the range the engine can tolerate. If the tank was below the needle from the get go, doing a prop hang makes little difference. Yes its lower now than before, but not massively different. Also a model like that will tend to only need 50-60% throttle to prop hang as it needs power/weight well in excess of 1:1. Glow engines all run rich around mid throttle due to compromises needed for acceleration from idle. This will easily cover any increased gravitational effect. Even if you punch the power to zoom out of a prop hang, the model begins to move almost immediately and this movement rapidly unloads the engine. Yes there is an acceleration load on the fuel in the fuel line, but it all works out fine if the engine tank is in the right place. Also, working 'just fine' is very subjective as we all have varying standards of acceptable performance. I want 100% performance all the time, but most modellers are happy if their engine works at all and while it might be fine for them, it will not be living its best life and giving its best performance. This 'its fine' approach also breeds problems for others as explained in the next bit. What engines cant tolerate is a change from gravity assist to resist. Its easy to spot. Show of hands for those who have owned or seen a model which starts off the flight ok and then gradually goes lean, overheats and quits leaving just under half a tank of fuel in the model. Tank is too high and should be lowered. What usually happens though is the needle is opened a bit to give rich mixture on the ground, and then the model gradually leans off during the flight but will not stop as it has this margin in the needle setting. Thus the myth of setting the needle a bit rich of peak is born, leading countless others down the wrong path. Yes setting the needle a bit rich 'solved' the problem, but it didnt really, it just masked it. If the tank were lowered the engine would not need to be run rich at all and performance would be better in every way. Modellers tend to cure symptoms, not problems as the actual root cause of an issue can be tricky to find. It also sounds strange to lower a tank if fuel starvation is the problem, but when you look at the whole system and understand how it all works together it makes total sense. Unfortunately this sort of system wide understanding often requires a reasonable level of technical training which is not available at a club level, and school physics classes are mostly long forgotten. So the best manufacturers can do is make recommendations and write instructions. However, as in your example David modellers who dont know what they dont know, and dont understand the reasoning then go 'nah, that dosent sound right' and we are back to square one with myths and folklore.

Beware of youtube and club experts. Most of the information from these sources is wrong and simply continues to perpetuate bad advice that has crept into modelling folklore. There is plenty of good information posted here, some less so but might not be wrong per se depending on the use case. First piece of information. Engines these days are very hard to kill. One accidental overheat or lean cut will not be the end of the world. The only exception to this rule would probably be the saito radials which love to throw rods. As you do not have one of those, i wouldnt worry. In the old days of steel liners and iron pistons you could kill an engine fairly easily, but still not as easily as was thought. Running engines stone cold and slobbering rich will be the best way to kill them. You need at good 80'c of temperature minimum in the engine for the thing to work properly. So many people want their engines to be stone cold. No idea why. This is spot on. You cannot tune engines by eye, only by ear. Forget counting turns on needles, forget rpm counters and other fluff. Listen to the engine and it will tell you everything you need to know. Yea you need to learn the language of engine farts and wheezes, but its not hard to do. No1 mistake is always tank placement. Folk install them too high and its game over. For all engines (2 and 4 stroke) without a pump the top of the tank should be in line with the centre of the carb. Not the needle (some have remote needles), not the fuel inlet nipple, the centre of the carb. Thanks to OS for their handy drawing. OS show the tank above the carb in this image, but the fuel level is also shown and there is an air space at the top of the tank. As we never leave air spaces in our tanks just use the top of the tank as a reference. This needs to be considered if engines are mounted inverted or on their side as the carb position will move with the engine. With the engine installed correctly fire up the engine, warm up for a bit then wind it up to full chat. keep leaning it off until the rpm begins to sag (might be very sudden). Then open the needle a smidge to restore the revs and its job done. On most engines it should take under 5 seconds to find this setting. Once you have this setting, leave the engine there for 10 seconds at least to make sure it holds on to that setting as it warms up. There is no need to run the engine hundreds of rpm rich of peak power* as this will do nothing for reliability and will simply increase fuel consumption and mess. The engine will unload and go very slightly rich in flight** so there is no need to worry. Waving the nose of the model in the air is also a waste of time. *some engines on tuned pipes etc will need to be set up differently. This guide is for normal engines with normal exhausts as this is what is being discussed **some engines (pylon etc) may not exhibit this behaviour due to the extreme change in load/rpm they see from ground to sky. This is especially true if they are also on a pipe. Slow run tuning is completely ignored most of the time but is very important as all running under about half throttle is controlled by the slow run needle. Setting it is simple if you follow the procedure. Warm engine up, Set main needle, throttle to idle for 5 seconds. Slam throttle full open. Does engine accelerate to full power? if no, and you just get a flame out its probably lean (rare), if yes but you get some coughing and spluttering its rich (extremely common). Lean slow run 1/8 turn and go again. Repeat until the engine will no longer accelerate to full power (lean cut) and then open the slow run again until it does. Reset main needle, check operation, fly. I have posted this video a bunch of times before but its an old video of me setting up a laser 150 4 stroke. If you want to skip the boring warm up start it about a minute in. The engine is very rich to start, as most are out of the box, and i lean the needles as described. The slow run is leaned a small amount between each acceleration and i very quickly find the lean cut setting. Its then a case of just dialing it in to my satisfaction. I fiddle and faff a bit more at the end as i am too much of a perfectionist, but hopefully it gets the general point across. The biggest takeaway is that the engine went from not running and completely out of tune, to perfectly tuned all within the space of a 4 and a half minute video. Engine tuning is not a week long epic, its very quick once you get the hang of it and the only way to do that is to just keep doing it. EDIT At one point in the video it looks as though i am tuning the engine with the tacho, which i normally advocate against. I am not, it just happened to be in my hand, but the reason i do not recommend it is made very clear as you can just make out the numbers on the screen and you can see they do not change despite very clear change in engine note. This is why you cant tune with a tach.

MA are the worst of all the props currently available. A friend used one of the same dxp of an apc on his YS and it crippled its performance. Better revs on the ground, but in the air it was just spinning the power into noise. The old graupner super props at least offered good performance. Their G sonic range run very fast, so you need to go up an inch or two in diameter or pitch to stop them howling like crazy due to the revs. The old bolly props were very good but i do not think you can get them any more.

Its a sign they are excellent at turning RPM into noise, and are as efficient as a railway sleeper bolted to the engine. On a cub or tiger moth they might be ok, but better alternatives are out there for something like this. Also on electric they will suck down amps like its going out of style. They are also very heavy and this can cause issues with phasing from the ESC as they do not spin up as quickly as the motor maps expect. Graham my advice would be to buy a 17x8 apc, nail that on and go flying. Yea they are ugly, but you cant tell that when its spinning and like on the c/g thread before, the object is to get it through the maiden flight. Nothing else matters at this stage. With that out of the way and the c/g, rates etc dialled in you may find it is more nose over resistant than you expect and a wooden prop has legs after all.

As i explained in my post, that was not the purpose of it. Have another read.

When my dad and his brother were kids they had a similar model with an ED Pepe on it. Usually it got to a few hundred feet and that was it, but on one occasion they accidentally got the tuning right on the engine and it shot off like a rocket never to be seen again....at least, until more than a year later when it was found on top of a Vulcan hangar at Scampton by a chap cleaning the roof. My Grandfather was a warrant officer on the station and so my dad was eventually reunited with the model. Once upon a time my dad and i were test running a dc sabre on the bench when it escaped and flew over the fence and straight through the hedge. Our neighbour was out so a covert mission was undertaken to find it!

I laugh looking back at my training. We (my brothers and i) did have some 2 channel gliders, but most training was done on my Dad's flair Puppeteer and CAP Harrow twin engine bomber! No buddy box either, just a futaba challenger tx passed between my Dad and me. I also stole flights on anything a club member would let me drive around. I remember my first landing distinctly. A flair cub i was borrowing suffered a deadstick and i went to hand the tx back to its owner. he just said 'it stopped while you were flying, you land it'. Not having much choice in the matter i just kept going in the direction i already was and put it down in the grazing meadow around the strip. It was a bit of a walk to get it, but it was undamaged so i called that a win. And i was...8? 10 maybe? Cant remember. A chap called Brian Fox would let me fly his aerostar 62 patternship. i can picture it now. It had a white fuselage, pale pink wings and i think a red top irvine engine... how on earth can i remember that so many years later?! Brian would also share his apple's with us kids. Slices were cut off using an APC prop designated for the task. I flew an absolute hodge podge of different models back then, with little formal training, but it was an MFA Cessna bought from Maplin's in slough when i was about 12 that really set me on my path. White fibreglass fuselage, red wings, OS25LA for power. I did my first proper takeoff with that model (which i can also remember like yesterday) my first roll (which scared the life out of me as i was afraid my dad would see it and tell me off!), and it became the first model i really had the confidence to throw around. I also got a 2 channel ben buckle style model with PAW diesel at a club bring and buy for a tenner as it was left over at the end of the sale and no one else wanted it. This model taught me a great deal and sparked my interest in engines as this diesel was something completely different. Its brought a genuine smile to my face just thinking back to my brothers and i as kids running around fetching planes ditched in the crop, flying, messing about building forts or whatever in the woods behind the field and generally having a great time.

In my experience there are (generally) two types of people. Those natural talent in a given skill, and those without it. I have taught naturals to fly and also plenty of non naturals too. The funny thing is, the non naturals ultimately tend to crash less and make fewer mistakes. The reason is that a natural pilot will whizz through their training and skip many of the basics as it just came easily. There was no need to teach (for example) the itemised procedure for a barrel roll as they just did it first time and it was pretty good so things moved on, without that lesson on planning things out ahead of time. Then with a touch of over confidence they stray into area's where their natural ability is not enough and the model ends up a crumpled heap. The non natural pilot has to work in a more procedural fashion, fly by the numbers so to speak and use their brain and careful adherence to step by step methodology to get them by as they lack the ability to just make it up as they go along. This is not a problem though as the non natural pilot can then brush up their skills within the framework of their various drills and procedures and ultimately may be able to out fly our natural pilot friend who is just winging it, making mistakes and not really sure why as they lack the core skills framework of our diligent non natural pilot. The best pilots are clearly a blend of the two. One of the chaps at my club who i have been helping with a large Spitfire is absolutely a non natural. That's no disrespect to the guy, its just a fact and one i suspect he would freely admit if it was put to him. What is also a fact is that he has responded very well to a methodical/procedural approach to flying the model and is now quite proficient with it. Proficient to the point where his landings are consistently better than many 'natural' pilots i have seen who have a crack at warbirds. He can now safely operate a model he never thought he would be able to fly. It just needed some training and a change of mindset. With that methodical framework in place there is less reliance on pure flying skill, which in turn keeps the model in the air long enough to learn the skills. On the rolling the wrong way, dont worry, i would imagine everyone has done it. As for a cure, its simply practice. Also, as is a theme, think ahead. You did a left turn, so chances are you need to move the stick right to level off. Have that in your mind before you start the left turn until your ability to assess the orientation naturally improves.

Leccy and GG. I think you are missing my point. I do not expect him to immediately take on a clubman schedule and deliberately broke a barrel roll (which most of us dont even think about performing) into a step by step guide of little building blocks, most of which have nothing to do with aerobatics at all. My comments about half cuban's etc were to demonstrate that the tiny building blocks to get you into loops and rolls then give you bigger blocks to build more complex maneouvers. While it sounds like a complicated thing to do, its not. If you can roll and loop you can half cuban as you only need to string the two together in the right order. When teaching i went into aerobatics often before takeoff's and landings as it taught several lessons which simple circuit flying does not..or at least, does but it takes longer. It also removes some of the fatigue of flying in circles, and forces a greater level of skill from the student as their errors are more apparent. Clearly careful coaching/guidance is needed but its not hard. I once took up a 10 year old lad who had never flown anything other than his 3 channel parkzone cub. I took off, handed him the tx for my 76 inch sport twin with 2 70 4 strokes and off we went. He could loop and roll it very nicely about 6 minutes later. For crying out loud the first thing i ever did on a model was a loop. I was only 5 and my dad told me to pull the stick back and watch what happened. His flair pup did a loop and that was that! Also even non flying people know what a loop and roll are. i know for a fact that many of my former students have been very excited to tell other family members or friends that they did a loop with their model. These family/friends are then excited for them as they understand what that means as the red arrows do loops. It makes them feel good as they achieved something they can share. In any case, the things you need in abundance for a nice landing are taught flying simple aerobatic figures like loops and rolls. Throttle control, attitude control, fine dexterity on the sticks etc. Slow flight and stalling is also something i would cover before landing, and the rudder too. Poor rudders, so oft forgotten. Training is just learning something you cant do already. Can you roll? no? Ok ill teach it. Its not hard just follow the steps. And you dont know the half of it. I would sabotage my students buddy box to make sure they did their control checks correctly. I wouldnt say a word if they missed it, just let them find out in the air. Some would say this was mean, but that was not the purpose of it. The point was, if they didnt catch it not being right then they either didnt check at all, or checked it incorrectly. Was it a mistake? was it laziness? or did i not make the procedure clear enough when i taught it. In either case, we would go back and do it again to make sure they got it right. The shock of them getting it wrong was also a wake up call to some who realised in that moment that their model was dead had i not taken control back on the buddy box. i would also disable their ailerons, or with them reversed due to sabotage teach them to land elevator rudder only. Why? Well i wont always be there to save the day or catch their mistakes. If they forget to plug in their ailerons, fluff their preflight, or the lead disconnects in flight then they need to have been taught how to deal with it. I would also give them a model miles out of trim and expect them to fly a perfect circuit before trimming it out. Why? well they will maiden their own model one day so its best to teach them how to handle a model that's imperfectly set up. How many times have you seen someone deck a model on a maiden while they fought to get it in trim? All this is the tip of the iceberg, but suffices to say that when i was done with them the requirements of an A cert were a walk in the park. 11 points out of a possible 10. if you get that procedure i wrote in your head, clearly understood and ready for deployment then you have it done. Even if it takes a week of reading it. Thinking it through, read it again. If you know what you have to do and can focus on doing it, practicing each part as you go. Where folk go wrong is they try and do it all on the fly. They get in the air and then start thinking about the procedure. With their attention divided between remembering what is next and flying the model it ends in tears. That's assuming they have a procedure at all. The point is, never fly the model into a place your brain has not already visited. Flying skill is important, but not as important as thinking ahead of the model. great, so its just a case of tidying it up. Actually as an experiment, using the procedure i wrote for the roll as a template, write one out for a loop. Add as many steps as you think you might need to complete a loop better than you did before. This isnt a test, there's no right and wrong, its just a way of getting the brain thinking about how you might break down something complex into smaller parts.

You can help yourself here by choosing some reference points around the field. A big tree, a building, power pole or whatever it may be. These references are handy especially when it comes to landing approaches. I used a variety of reference points to help some guys at my club with their move into larger warbirds. There's quite alot going on when landing one of those (gear, flaps, rate changes etc) so breaking it up into little pieces, and assigning each one a reference point makes the job easier. Clearly you arent landing a warbird just yet, but the principal is the same for you. A handful of reference points scattered about can help with your overall awareness when you catch them in your peripheral vison as you fly around and specific ones can guide approaches. A desired touchdown point for each landing can also be handy and if you overshoot, go around. This will prevent you flogging a dead horse of an approach and running out of runway. Like the other guys i wouldnt recommend that. as you are not in the cockpit you just just confuse yourself when not flying away. Aerobatics. If you havent already its time for loops and rolls. They demand accurate stick movement, circuit planning, careful use of power, show the model in unusual attitudes and a variety of other things that will strain your brain. I taught aerobatics way before my students ever went solo as they revealed shortcomings in their flying far better than laps of the patch and it was easier to nip those bad habits in the bud then than later down the track. They were also so deeply focused on their loop/roll that they forgot all about their circuit flying and it often improved as they were not over thinking it so much. Rolls are a great intro as they are relatively easy to do but can be tricky to do well. They should be split into several parts flown in sequence and you do not get to do the next part until you master all of the ones leading up to it. Dont just smash the ailerons over and hope for the best, you have to plan it as use a full pass from one side of the patch to the other so you do not rush it. For example. Fly a normal circuit round to start the whole thing. Pick a reference point to start the run in to start the roll. Be at this point at the right height, direction and speed with the wings level. Run in to a reference second point (only a few seconds after the first) and add a bit of power (you will have to learn how much you need). then wait a second or two. 3rd reference point pull the nose up say 40 degrees above horizontal and centre the elevator With that all stable get the ailerons over while holding the elevator in the centre. Once inverted pull the throttle back to say 1/4. Ideally you should be directly ahead of yourself as you reach the inverted point. once rolled out to wings level wait a second or two then pull up to level flight add circuit power back on the motor. Return to your original circuit. That little lot will get you one barrel roll and more or less any aileron model will perform it. Despite being the simplest aerobatic thing you can do there is a far bit to think about and it pays to break it down into these little chunks with a go/no go on each. Dont get the nose up enough or the wings arent level? dont start the roll. Fly out and start again. Its worth while going around as a rushed effort from the wrong position will simply end up in a crash. The point about being inverted in front of you is getting more advanced, and its even a point of note on the B certificate. But its still something you can achieve so why not start practicing it early? Its also another nice reference point to aim for and will be a challenge that will require improvement in all of your skills, which is sort of the point. It will also scare the life out of you the first few times, especially when you get it wrong, which you will. So do your first one's at a half decent height. Not in orbit so you cant see the thing, but not cutting the grass either...at least, not yet. Work your way down as you become more proficient. Being scared half to death is no bad thing either as you end up having to rescue the model from a bad spot and this, again, is good practice. Also if remember how you got there you can avoid doing the same thing again! Loops are another whole story, but its a similar procedure. With loops and rolls mastered you can combine them for a half cuban 8, immelmann, reversal or even a quarter clover once you get dead fancy with it. That little lot covers most aerobatic routines and its just a case of building on the basics of control, circuit planning, aircraft positioning and all that stuff. Oh and its more fun than flying in circles. Just expect your flights to be only half the length as metal fatigue will creep in very quickly when you start giving it a go.

No, its not. In fact its just rude and selfish. The mods know its broken, they are working on fixing it. What more needs to be said? I am sure their attention span is sufficient to remember they need to fix it and perpetual whinging will not enhance their mood or increase their speed. Its a popup, a tiny insignificant window that chills out in the corner of the screen. Just ignore it. I cant even begin to understand why this is such a big problem. The thought of anyone being so fragile that a malfunctioning popup on a toy aeroplane forum is causing such distress that they might leave is utterly ludicrous to me. Honestly what's next? Tears at Tesco as your favourite brand of biscuit has been out of stock for a few days due to floods? The staff perplexed as you sniffle out of the door saying you are going to Sainsburys from now on. Its just pathetic. Im complaining about complaining, so do i get double points?

When the Laser site went down i very quickly discovered that whinging about it didnt fix it. No matter how many incredulous modellers called or emailed to whinge it did not matter and the website remained broken as, apparently, whinging is not a cure for broken websites. Who knew? Being aware of the problem with the website i told the tech people, and while the tech people did...something, it remained broken until they were done hacking the matrix or whatever it was they did. This took many weeks as it was a bit of a dogs dinner and our web host is rubbish. Whinging will not fix it so why dont we just leave it alone? If my experience is anything to go by it is not in the least bit constructive and will only serve to cheese off those who are probably working hard to rectify the problem. It will take as long as it takes. They knew it was broken after the first handful of posts. The 3 following pages of whinging is not helping anyone.

Looks ace, and i wouldnt be worried about the hinge type. Control surface loads will be very low and more or less anything will work fine

true, but surely that is another reason not to buy them. At least you can take/send a branded servo back to the shop you bought it from. Flash website and shiny anodising on the product is easy. Not much good if the electronics suck. However many people shop with their eyes and bling sells.

everything apart from the servos themselves has been isolated and tested as good so i would say he has found the actual problem. You also do not have to spend any money as returning these servos as faulty will get you your money back.

I think the issue is with the quality (of lack of quality) of the servo. A quick google search reveals them to be bangood/amazon whizzers and prices as low as £10 A servo of this spec (30kg) with an unknown brand for that sort of money is a massive red flag and would not touch them with a 10 foot pole. I assume this mustang is a reasonable size? 1/5 or 1/4 scale? If so i would favour good branded servos from Futaba, Hitec, savox etc of a lower spec. A 10-12kg digital from any of these brands would easily handle a P51 of 1/4 scale and at 1/5 scale 6.5kg-10kg would still be more than man enough for the job. Not only is a branded servo likely to be more reliable and thus much safer, its also far more likely to meet the specs listed on the box as 30kg seems optimistic to me. The brands i mentioned all have ranges of standard and HV servos. Personally i used the standard stuff as my warbirds up to 1/5 do not need HV, but if you use lipo/fe power then HV is available. Its not worth risking the model or anyone it might hit by using cheap gear with questionable reliability.

As Ron says, it will be fine I wouldnt worry. Just mount it under the engine

I do not think you will be wheezing round and unable to loop. As Chris says its mostly an energy management sort of deal and it will loop for sure. Plenty of people have flown the 70 inch ESM warbirds using our 150/155 and they are normally around the 15lb mark. My pica p40 was this span and weight too, it was fine. You could use the 240v, then fit a bigger prop to tame it a little. But the 240's i have in service currently are delivering great performance in models of up to 23lbs so at 16, it would be speedy!