Piers Bowlan

Well done Nick your perseverance has paid off in spades. Amazing the difference a 2cm change in C of G makes. Now come on Robin when are we going to see your T11 completed and airborne?

Big wheels look OK on a Cub but would probably spoil the effect on the Vampire not to mention have an adverse effect on performance. For me it is all about the flying qualities and a landing gear only adds complication, frustration, drag and weight with a model of this size. But each to their own.

Alan Head (SAS) makes the Wildthing and Fusion in various sizes, neither 'Zagi types' I have the Fusion 60in - thats good. Most of the work is already done for you, just add radio and strapping tape. Much better performance than a Zagi, particularly with penetration. Very cheap too!

Ian, I purchased the ARF version of the Durafly Vampire because the field I use necessitates hand launching and a belly landing. Your woes with this model all seem to stem from the landing gear; wheels that bind, retracts that don't, grass that gets sucked into the fan etc. Like you said the entire model cost you a hundred quid including a couple of LiPos. Considering how cheaply the Chinese toy trade turn out these models (in their thousands) and what Durafly no doubt pay their suppliers for the landing gear sets, do you think it very realistic that they are reliable? Fit for purpose? Probably not. The wheels are tiny in comparison to even a landing strip as smooth as a putting-green. For scale, think of a full sized Vampire landing in a field of elephant grass -messy! The stresses on the landing gear attached as it is to EPO (even with a gentle touchdown), are enormous. My advise is to ditch the landing gear (the model will be lighter/fly better without it) and enjoy the model for what it is; a fun, foamy, Scale-ish, model that you can bung in the back of the car. You will be able to use a bigger battery too because of the weight savings = longer flight times to boot. Still good value in my book. Just my 2p worth!

Hi Elliott, I tend not to use scalpel blades (Swan Morton) myself but the small size retractable blade 'Olfa' cutters available from stationers and DIY shops work for me. The blades are segmented so you can keep breaking off a section when they lose their edge. The blades with the 30 degree point are best. The replacement blades are cheap too. As far as cutting thicker sheets of balsa (5mm+), across the grain, I find a razor saw is essential. Again Swan Morton make them but I have one made by Tamiya which I prefer. Alternatively I find it better to gently but repetitively score the wood (against a steel rule) rather than trying to cut through in one go and end up crushing the wood. I agree with BEB, a large cutting mat is essential to prolong the life of the blades. Other useful items are a razor plane and a perma-grit block for sanding. The perma-grit blocks are not cheap but last forever. Once you 'discover' them you will end up buying a collection in various sizes, I did at any rate, much better than sand paper. Before you know it you will soon be hooked on this absorbing hobby.

I agree with Ady, Nick, the C of G does appear to be rather too far aft, judging by the model's wayward behaviour in the video. I moved the C of G of my Durafly Vampire 21mm forward of the balance point indicated in the instructions (290mm rather than 311mm from the nose of the aircraft). I flew it last week and the model was transformed! My Vampire was tamed, very stable, no more 'roller-coaster ride' and no squirrely behaviour at all. The Vampire, both model and full sized, has quite a short tail moment so perhaps it has a narrow C of G band, being sensitive in pitch. A forward C of G would tend to calm things down or at least it did with my model. The rest or your setup seems OK so I hope you are able to effect some repairs soon and try a more forward C of G. I don't really think the issue is the fins (although they are probably rather small). Piers

Nick, the wing loading is not excessive, did you build in any washout in the wing, it will ensure the wing root stalls before the wing tips and so reduce the likelyhood of a spin should the aircraft stall. I also noticed in the video some gaps between the ailerons and the wing. you should seal these by covering the gaps with profilm/solarfilm or whatever. It will make the ailerons more effective although roll rate does not seem to be a problem! Also did you dial in some differential aileron on your Tx.? It reduces adverse yaw and again will reduce the likelyhood of an incipient spin at low speeds. If you spin and you don't have any rudders you are doomed! Just my ten penny worth. Regards, Piers

I wouldn't worry too much about epoxy and EPO foam, some people use it all the time. I have heard anecdotally that it tends to break in the event of an arrival (crash). Maybe that is a good thing as it stops the foam itself from breaking? As long as the epoxy does not 'let go' in the air! With your maiden scheduled for this afternoon I felt that I should brave the elements and test fly mine again, despite the rain. No pressure then! I set the C of G with a Great Planes balancer to 290mm from the nose of the aircraft. This corresponds to 17mm infront of the booms (on the underside of the wings of course). That is 17mm and not 2mm as printed, in very small print, on the 'instructions'. Looking at it another way, 70mm from the LE, aligned with the booms (hope that is clear!) It flew brilliantly! Very smooth with a spirited climb on the 4s 2200mAh LiPo. I set the elevator to + - 12mm and the ailerons to +8mm -5mm. As others have observed it can fly very slowly, infact with a little slope lift in just five knots of wind I was having trouble getting it down until I slowed it right up. For imfo I only flew it for about three minutes as my transmitter and I were getting rather wet in the persistent rain and anyway the Vampire was never an all weather fighter! I only used 920mA from the LiPo. I have the ARF version and flew it without retracts (long grass) so a bigger battery would be an advantage to avoid having to add lead to the nose as I did. I also fitted a Plush 60A ESC which is a bit overkill but I have heard that there can be overheating issues with the supplied ESC in the BNF version. Probably not a problem on a cold wet day like today.

Join the Air Force. Which one? Not ours surely, they are all being laid off what with the cuts to the defence budgets. Harriers all gone, what a pity but then, I don't have the 'global overview'! Big Airways absorbing BMI pilots for a year or so but then things will be looking up for prospective young professional aviators in the Civil Aviation sector what with a world shortage of pilots looming. Airlines will be looking at anyone with a professional licence if they have the right stuff. Ex military pilots are always sought after by the airlines, there is usually not enough of them.

B744 = Boeing 747-400, (a passenger aircraft) as opposed to the Boeing 747-200 colloquially referred to as 'The Classic', or dinosaur, (if you fly the -400) -just joking guys! Not so many -200s around now, mostly freighters. I did a bit of Air Taxi work in light twins a long time ago. It was certainly varied but it was full of hassle with a lot of waiting around and then it was, go go go! (it is called hurry up and wait!). You can't plan your life round it and can't live off the pay either, let alone keep a family. As for 'getting home by five everyday' do you mean 5am Mark? I am often told (by non pilots) that it is 'just like driving a bus'. It is just easier to answer 'yes it is' as pilots are generally a fairly self depreciating bunch. The fact that the training takes a while and costs a bit of dosh and after a thirty year career I am still learning. So maybe there is a slightly more to it than driving a bus? UK NATS:- best in the world by far. Sadly ATC in many parts of the world don't have quite the same gentlemanly attitude! Turbycat, I agree it was a lovely aeroplane. I owned G-AWMR for a number of years keeping it at Redhill originally (Tiger Club) before flying out of a strip near Stevenage. I did a lot of flying in it 1980 (hours building) taking it round the coast of Britain including a landing at Doonray (Thurso). I did another memorable trip to Budel in Holland in company with Roy Watling Greenwood and Ken Brown in their Turbulents. I have an ASP 160 twin lurking in my shed to go in a Turb model 'one day', probably when I retire!

Phill, I started out in engineering over 30 years ago but quickly trained and gained a UK PPL before getting a CPL then ATPL via the 'instructor route'. Its a long hard road and even then it cost me about £10K. Today you need to be trained at an approved school and you won't get much change out of £100K. My first job was flying Shorts 330s based in Aberdeen initially. It was very badly paid, involved flying long hours through the night and often in atrocious weather. I did that for a couple of years until the company folded. I Joined BCal in 1985 and flew BAC 1-11s for three years before that company was taken over and I flew Boeing 757 and 767s on short haul routes and charter for about eight years. It was hard work and anti-social too as you are often away from home and usually at the weekend, especially if you are junior in the company. OK for a single guy but a different ball game when you are married with a young family. Airline flying can be tedious at times but what job isn't, especially when you are very tired (which you often are) but I would never call it boring. It is a very rewarding career and it can be fun too. It is also one of the few careers where your job is on the line every six months when you are checked in the simulator;- stressful! If you are a young guy Phill, have three good A levels or a degree then you may be able to get sponsored by an Airline to do the training. You will need to convince them that you are totally committed and focused to becoming an Airline Pilot and want to work for them. If you have a PPL or have done a few hours flying or a gliding course this may help to convince them but it is not essential. The competition is stiff but someone has got to do it so it might as well be you! If it was easy it probably wouldn't be worth doing. I have been flying B744s for many years now. I still think it is a great job and if I had my life over I would follow the same career path. I hope this helps.

Hi Ian, I set the C of G on mine as per the instructions, ie 311mm from the nose of the aircraft. From the moment the model left my hand it was a roller coaster ride with the balance point obviously way too far aft. After a short trawl on the internet I found that 290mm from the nose to be closer to the correct C of G position on the Durafly Vampire. I havn't had a chance to fly mine again since but I will report back tomorrow morning when I have. For info I used + - 8mm elevator with 30% expo. I can't comment if this was good or not as the aircraft was unflyable because of the aft C of G! Hi Capt Kremen, I tried UHU Por for the first time. Big mistake. I found it took forever to dry and was very messy- perhaps it is just me! In the past I have used regular Cyano (not even foam friendly) on EPO (with kicker) to very good effect. I think I will stick to Cyano in future (if you will pardon the pun). I have been told that Epoxy does not stick too well to EPO despite looking like it has stuck fast. I have not tried epoxy myself on foam.

I meant to say that most Camels were fitted with Clerget rotary engines although some were fitted with Le Rhone, Gnome and Bentley BR1 (rotary) engines. The pilots used to blip the throttle by switching the ignition switch on and off to reduce power as closing the throttle involved adjusting the mixture. Great! The Camel in the video I think is a replica in the US so who knows what engine it is fitted with. Whatever it is the pilot was blipping the throttle coordinated with application of full left rudder to keep straight.

The Avro 504 and Sopwith Camel both suffer from a narrow track undercarriage plus a tiny rudder. Once in a three point attitude in the landing roll the rudder is masked by the fuz, plus the fact that they are flying very slowly indeed so the effectiveness of the rudder is negligible. This is why the throttle is 'blipped' to effect a draft over the rudder to increase it's effectiveness and so keep the aircraft tracking straight despite the crosswind. A tail skid instead of a tail wheel was also unhelpful as far as ground handling was concerned, another reason for blipping the throttle to effect a change of direction with that tiny rudder. Hardly surprising they took off and landed dead into wind if they could. In the video of the Camel it is landing in quite a stiff crosswind as Keith pointed out, it was crabbing into wind not side slipping as someone suggested. As the pilot flaired he was using full rudder and gunning the throttle for most of the landing roll to stop the aircraft weather cocking into wind - ground looping. As for "'a good example of a relatively benign aircraft of the same period" I am not sure I would describe any aircraft of that period benign! They were underpowered, draggy and most had some very bad handling characteristics. Not least of which was the rotating rhone radial engine fitted to some aircraft of the period with its gyroscopic effect causing some vicious handling characteristics. The Camel was particularly bad in this respect. Did I mention the engines were very unreliable?

The narrow track landing gear seems to be the culprit. Also the model appears to lose directional stability once it is in a three point attitude suggesting that the fin and rudder are not large enough. As bbc says, the pilot of the full sized a/c would have been working pretty hard with the rudder pedals to keep the aircraft straight through the landing roll. I can't see fixing the wheels to the axle to be of any benefit with this particular problem. Also, I think toe-in may exacerbate things (toe-out?). Make sure you have LOTS or rudder travel. Once you are down (or after the first bounce!) and you notice the aircraft yaw be quick to apply plenty of opposite rudder to keep it tracking straight. (On the video I can't see if you are) Like the full size always try and land into wind if you can. If you touch down with any yaw on, you will surely ground loop (which is what is happening) with that narrow track landing gear. One other suggestion is perhaps moving the landing gear forward a tad which might aid directional stability. Not very scale perhaps and a right pain to do but it might help. I hope you sort it out Peter as it looks like a lovely model in the air. The final part of the landing roll does somewhat spoil the effect!

In a small electric model on a 3s LiPo and no more than four 9g analog servos using the BEC is usually fine, so your Fun Cub should work with the stock set up without any worries. As Pete intimated in an earlier post the problems usually arise when you use more cells and more servos. In this situation then a UBEC is a good solution as it saves you the extra weight of a stand alone Rx battory while eliminating the hassle of making sure the Rx batt is always charged prior to flight. Just make sure the UBEC can handle the current your servos draw. If a separate Rx batt is what you prefer then AAA size could be adequate in a light weight model. The size of batt required is entirely dependent on how much current your servos consume and how long you plan to be airborne. For example in an electric thermal soarer due to the lower wing loading carrying a separate Rx battery may not adversely affect performance. However in an EDF or helicopter, where every oz. counts, a UBEC may well be preferable.

Hi John, The Chinese manufacturers frequently under spec. the ESCs in their RTF creations, something you have already discovered sadly. Personally I usually use a margin of 30%-50% (not 10%-20%) and never use an unbranded ESC unless I really dislike the model! As far as your MPX Fun Cub is concerned although Multiplex have their models manufactured in the Far East you can be sure that their Teutonic quality control will ensure that the ESC supplied with their MPX 'Powerset' (if that is what you are using) will be well up to the job. In fact to switch to a 45A 'Turnigy Trust' would be a retrograde step in my humble opinion as I suspect the build quality of the MPX unit will be superior. Have you got a watt meter, as you are a bit in the dark without one, if not?

Maidened the Durafly (HK) Vampire this afternoon. Interesting! No shortage or omph on 4s but I think the C of G was a tad too far back as it was a roller coaster ride even when I switched to low rates (7mm up and down with -30% expo). I think I was also a bit too enthusiastic with setting up aileron differential as the model was yawing strongly in the same direction as the roll. I don't think directional stability is the model's strong point with those small fins, particularly at low speed. Maybe that is why they made them bigger on the full size T11/T22? In the end a gentle touchdown was effected- into a bramble bush. Glad you weren't there Robin! No harm done apart from a few cuts and a bruised pride - in future I think I will stick to gliders! Will report further after a few changes.

Excellent job Nick, hope it flies as well as it looks. Nice floor too! Here is my foamy Durafly ARF Vampire from HK. Hope to have a flying shot of it soon.

XT60s are the new kid on the block so I doubt many will be using those at present unless they are new to electric flight. I quite like them but I have melted one or two when soldering. I don't seem to have the same trouble with Deans. Clearly my technique needs more work! Piers

Hi Trevor, Nice Photos and I am glad to hear it flies so well. I bought the ARF version so fitted my own servos etc. A bit like an airfix kit except I thought I would try UH Por adhesive for a change. I must have had a rush of blood to the head as it was a big mistake, glue everywhere! I will stick to Cyno in future. I decided to omit the retracts as my strip has quite long grass and I felt they would only add weight. I havn't maidened mine yet but I am looking forward to it as all the reports are very positive. Piers   Edited By David Ashby - RCME on 30/07/2012 09:41:00

Posted by Myron Beaumont on 28/07/2012 19:32:33: Hellcat You said you were a "non engineer" and liked the AW article . Well ,as a qualified mechanical engineer (Rolls Royce -Aero engine division -Derby) I find his articles pathetic in content and just so far away from proper workshop practice .OK for 5 year olds starting out with a DIY attitude from their mothers Grumpy but knowledgeable Myron You don't need to be a qualified mechanical engineer to splash out £300 (min) on a Router and router table to produce Alex's balsa LE strips 'professionally'. But that would be extravagant and beyond the means of many if that is all you want the router for. Hence AW 'amateur' yet practical approach of utilising his pillar drill and a suitable guide. As for 'proper workshop practise' that is down to the individual but a router table or AW's lash up are both potentially hazardous without due caution. I am sure AW will be careful! I appreciate AW's workshop ramblings. His articles are light hearted and fun which is what this hobby is all about in my book. Sadly one or too people take it all a bit too seriously for my liking. And when I say, 'light hearted' that is not to say that I don't take safety seriously.

Well I have been doing my bit. I ordered one of the new Vampire kits from DB Sport and Scale (Here) as it is the right size for my Wren 44. It will just have to go on my 'kit mountain' for now (no time, sadly).