Peter Jenkins

Rob, think of it this way. The moment an aircraft rolls, while the total lift is unaltered the component of lift that fully supported the weight (i.e. acted vertically) has now reduced by virtue of it being tilted from the vertical. Therefore, the vertical lift component reduces and with weight unchanged the aircraft begins to descend and the wing is now meeting the airflow with a greater AoA. The newly created horizontal lift component will now act to turn the aircraft towards the lower wing thus making its presence felt. The resulting slip (inwards) will bring the fin into action and that will steer the nose towards the lower wing and cancel out the slip. Unless you then apply a small dose of up elevator to recover the vertical lift component, the aircraft will continue to descend in a turn. In full size aircraft, students are taught to increase power sufficiently to maintain speed and height when turning an aircraft and then removing the power as the aircraft rolls out onto the desired heading. With model aeroplanes we don't tend to do this as we are not sitting in the aircraft viewing the way the nose drops below the horizon without applying power. We also cannot see the change in airspeed as we have no air speed indicator to help us with our control inputs. In full size you need increasing amounts of power with steeper bank to maintain altitude and speed. Eventually, power runs out and you can choose to maintain height or speed but not both. For example, a Hawker Hunter F6 (the pure fighter variant) could pull 7 g and just maintain height whereas a Hawk could pull more than 7g and maintain height. So, in a turning fight, all other things being equal, the Hawk would outturn the Hunter and kill it! With model aeroplanes, which in comparison are grossly overpowered, just pulling back on the stick is sufficient to carry out a level banked turn. I expect those who fly FPV will notice these effects much more easily as they are "in" the aircraft.

If you are thinking of taking a B Certificate test, you might be interested to know that Area Achievement Scheme Coordinators are being urged to run workshops for Examiners, ACEs, instructors and potential A and B certificate candidates to attend. The idea is to encourage standardisation in the way the test is conducted and assessed. Test candidates can get first hand experience of the standard required. They will also be able to be tested for their A or B provided they flag this up before the event. Ask your Club Secretary to let you know when one of these workshops is to be held near you.

Posted by Biggles' Elder Brother - Moderator on 14/08/2014 22:21:16: In practice the BMFA is directed by a relative small cabal of individuals re-elected year on year - if you want to find out who just take a look at the pictures of individuals in black ties handing out awards at the annual dinner! BEB - isn't the key word in your sentence above "re-elected"? So who does the re-election? If you don't participate don't expect your voice to be heard. The status quo will not change unless sufficient people stand up and are counted - i.e. turn up to vote in a new committee if you are dissatisfied with the old one. Muttering from the sidelines will not have any appreciable effect. That's all I'm saying. This is not yet a proposal and since a third party is paying for the Feasibility Study it does not impact on BMFA funds. When and if it becomes a proposal then I'm sure there will be sufficient information to allow Clubs to let their Area representatives know what they think of it. Isn't that what democracy is about? John - how often have you or your Club made your views know to your Area Committee and helped to formulate what your Area Rep was to say/Vote at the next Council meeting. If you/your Club have not done that, then I would strongly urge you to do so. That's the way you get your point across - not answering a questionnaire on a website. The questionnaire, is not a proposal and has not committed the BMFA to anything.

There seems to be some interesting views on the BMFA in many of the posts on this thread. I thought it helpful to make a few points about the organisation of the BMFA so that contributors to this thread realise that the BMFA is not run by some small group of people who are cut off from the grass roots. Let’s start with what the Organisation looks like. First, there are the Clubs and their members. Clubs are grouped into a number of Areas. There are 13 geographic areas that cover England, Wales and Northern Ireland and one, RAFMAA which covers a very large area that encompasses where ever the RAF is based. Next, Clubs within an Area elect an Area Committee from candidates proposed by the Clubs. One post is that of Area Delegate to the BMFA Council. Finally, the BMFA Council is the body that makes the rules. The Council consists of the 14 Area Delegates (who under the rules of the game become Directors of the BMFA), an Executive whose 9 members are elected by all BMFA members regularly and a number of others who make up a total of 32 members. I’ll skip over the many Technical Committees who are represented on Council for brevity. So Clubs have 14 Delegates to do their bidding at Full Council meetings which is where the discussion and decision on the National Model Flying Centre will take place. Some contributors to this thread seem to think they have no influence on this decision. You are WRONG BUT you do need to make an effort through your Club to advise the Area of your views so that they can be represented at Full Council. Areas are crying out for Clubs to participate more actively than they currently do to this process – you will be pushing on an open door! The Executive have regular meetings prior to the Full Council meetings of which there are 3 per year and, of course, the Annual General Meeting which again is open to all members to attend. Any recommendations that the Executive wish to make are put to Full Council, debated and voted on BY THE FULL COUNCIL. The topics to be discussed are circulated to Areas who circulate them to Clubs so that Clubs can come to the Area meeting before Council to give their views. Clubs can also email their views to their Area Committee who will be only too happy to have this input. Clearly, attending the Area meeting allows your Club representative to speak directly to the Area Delegate and other members in order to arrive at the Area’s consensus. There is also an Areas Council which, as it name implies, is the forum for the Area Delegates to meet and discuss issues that are then sent up to Full Council or to debate issues that Full Council passes to the Areas Council for advice. Sadly, attendance by Clubs at Area Committee meetings is very patchy but this is where Clubs get the chance to debate issues that will be coming up at the next Council Meeting and give their Delegate input so they know what their Area wants them to say and also to give the Delegate the guidance on how they want them to vote. I hope this short description of how the BMFA functions will be useful to those who are unaware of how democracy in the BMFA functions. Like all democracies, if you can’t be bothered to make your views known you are not in a good position to object to any decisions which are then made. So, make sure that your Club Committee knows what your views are, find out who is the Club’s Area representative (could be quite illuminating) and make sure that they either attend the Area meetings or at least convey their views to the Area Committee. Some posts have indicated that people think the BMFA is merely the provider of insurance and that they would be minded to look elsewhere for their insurance and leave the BMFA. Remember that the BMFA is the loudest aeromodelling voice in the CAA’s ear. What the BMFA says carries great weight with the CAA. This covers input to the guidance document, CAP 658 – the equivalent to the Highway Code – that interprets the broad statements contained in the Air Navigation Order, an act of Parliament, and this guidance is distilled into the BMFA Handbook. The ANO is the legislation that covers what we may and may not do with model aeroplanes flown in UK Airspace. Just to be clear, UK Airspace begins at ground level so even flying in a park or your back garden you will, as soon as your model takes off, enter UK Airspace and become bound by the ANO. There are many other areas that the BMFA ensures that your interests are protected such as securing and defending the use of the 2.4 GHz band for model aircraft, but enough for now. I hope that helps contributors understand how they can influence the National Model Flying Centre discussion and any other aeromodelling issue for that matter!

There is a short presentation on the proposed National Model Flying Centre on the BMFA website here.

The long awaited Multi-rotor A and B tests have now been launched by the BMFA. Follow this <<LINK>>

Hi Steve, hope you've recovered from having your model eaten by the locat vermin! The thing about precision aerobatics is that it's very difficult to make progress just by yourself. That's why trying to get to a competition either to watch or, better still, take part is so useful. You would need to find the equivalent of the GBR/CAA in Spain to find out where the comps are held then go along to one local to you. In the UK, if you look up the competition calendar for the GBR/CAA you'll find that the competitions are spread from Yorkshire, Derbyshire and through the Midlands into East Anglia. Basically, where the Contest Directors can find clubs who are prepared to give up a day's flying at the weekend. I can assure you that you don't need to be a brilliant pilot before you take part in a competition but you do need a B Certificate. You will learn more from flying in one competition than all the practice you care to do. Take away that competition experience and build on it and see how you get on in another competition - it's addictive! An alternative is either to go along to or to fly in a New Pilot Open Day. I will be organising one again in the East Anglia Area next year. If you are interested in taking part in an NPOD please feel free to PM me but I will be giving priority to those in East Anglia Area Clubs as I hope to get funding again from the EA Area Committee. Everyone who has taken part in one of the NPODs held in the past 3 years has commented on how much they have learned from both their mentors and watching the other pilots fly. You could also try attending one of the Classic Aerobatic Association events - check out their thread on this forum. There is also the IMAC world, I think that most of their competitions are in Wales and the North East. You will find loads of help at competitions from the more experienced pilots. They are only too pleased to help newcomers to improve their flying. Just watching competition flying also helps you to see what the manoeuvre should look like, how big it should be flown and how far out is right. Nothing wrong with having a break from precision flying to fly in an abandoned fashion for a bit of light relief but don't allow your bad habits from before precision flying to creep back into your precision flying! If you avoid flying at an angle to the desired line you will find that very quickly even your light relief flying will be more erm precise without actually trying to do so. Peter

Terence, it's a common misconception that large side area causes difficulty in flying accurate lines. Once in the air, the aircraft is unaware of a cross wind since it is moving in a block of air. You are standing still so you are aware of the crosswind. The problem with flying accurate lines in cross winds lies with the operator and rarely the airframe IMHO. I have seen people fly to far higher standards of accuracy with the same model as me! I needed to up my game. If you have not already had a look at this thread, you may find it useful in helping you with your aerobatics. Peter

All good points L Plate!

Andy - I tried using a Simulator when practicing the 2 rolls for the B Cert. Never really got on with it as you had to fly low to see the ground and get a reference point. Problem was I crashed a lot! It did help me a bit but much more useful is to use a stick model and to visualise what control inputs are needed as you "fly" it round the manoeuvre. The other issue is that if you fly fast, small manoeuvres, you have less time to decide what inputs to give and when. Try flying as big a manoeuvre as your plane will comfortably cope with. If you are short of power, a quick and relatively cheap solution is a small throttle pipe. My Wot4/Irvine 53 combo was pretty good without a pipe but with the mini pipe I have unlimited vertical performance. This is a blessing in disguise since, in comparison with my F3A model, the Wot4 needs careful attention all the time as it is very prone to wander off course as the slightest provocation! Flown with lots of available power (used sensibly) and very low rates, it all becomes much easier to control and to see what's going on. I gave my Wot4 to a guy who tends to fly a foamie 3D machine and its all over the sky. With the Wot4 and the very low rates, he looked like he was flying on rails. Try reducing your lowest rate and see if that also helps with your simulator work.

Well, I've not stepped in to answer Al's point above to see if anyone else would post. As no one has taken up the challenge, here goes! The first thing to remember about precision flying is that it requires precise flying! Obvious but not so easy to achieve. The starting point is the aircraft trim. If you are reading this post for the first time, go back to the beginning of this thread to read about how you trim an aircraft. The second thing to remember is that you must be very critical of your own flying. If you are trying to get into precision flying on your own it is quite difficult to know what is the standard required. If you have a precision aerobatic pilot in your club go and pester them or just watch them fly and take note of how when they fly level they are LEVEL with no, or extremely small excursions from level flight. Also, watch how they compensate for wind drift so that the aircraft is maintained at a constant distance out from you. Go up and ask them if they'll critique your flying and advise on what you should do to get better - then go and put that into practice. Third, don't fly too close to yourself. A standard 50 size model should be flown at around 80-100 meters out from where you are standing. A full 2 mtr model should be flown at 150 mtrs out. As Al has said above, flying the line is a good exercise, to develop your skills. It's never boring because each run will be different as you make, identify and correct your errors. If you cannot fly the correct line at the same height and parallel to you at the required distance then you are wasting your time to press on with learning an aerobatic schedule. Doesn't mean to say you just fly lines but don't expect to be any good at flying a schedule unless you can fly the line consistently, You can vary the end turn round manoeuvre from reverse half Cuban 8, half Cuban 8, Stall turn (vary with canopy to you and then belly to you) but don't do flat procedure turns unless you are practising for your B Test. Having low rates helps enormously when flying precision aerobatics. Here, its very much a case of less is more! If you don't have anyone to help critique your flying, then post here with the problem you have and I, or other contributors, will try and help. Once you can fly a line accurately, start to work on flying the high line. That is do a half loop with half roll (Immelman in aerobatic parlance) or a half square loop with half roll to get you to a good safe height from where you could comfortably perform a bunt (outside loop). Then recover to your normal line height with either a Split S (half roll followed by half loop), Immelman or half square loop and roll. Once you can get round your standard height line and your high line repeatably and can correct for the crosswind effect on your flight path you are ready to start doing centre manoeuvres. Good luck.

A commercial pilot friend of mine has said that the term chandelle is not used in commercial aviation but the term is used in a number of US flight schools to describe a maximum performance climbing reversal. So, I suppose it's one of those custom and practice things, or language, where the same term means different things to different users. As far as I'm concerned, I'm going to stick to the gliding, as opposed to the American, definition of a chandelle but will be alert to the possibility of misinterpretation. A bit like the Immelman turn can mean different things to a WW1 aficionado and an F3A practitioner. Like they say, don't assume, check!

Cymaz Absolutely agree with the comments above. I also learned how to do a chandelle in full size gliding and the reason was that in a glider you don't have any slipstream to do a proper stall turn - hence you need to fly the glider through the whole manoeuvre and are never stalled as such. Where you draw the line between a chandelle and a wing over is another thing but I suspect that the chandelle is flown at a lower speed over the highest part of the manoeuvre compared with a wing over. Folks in your club who think that a climbing turn and a chandelle are one and the same thing are sadly mistaken or misinformed.

We shouldn't make the mistake of associating US government procedures with UK government procedures. They have a written constitution and we don't. Their Government consists of 3 elements: the Executive; Congress and the Supreme Court. No one is actually able to lay down the law and that's the way the citizens of the USA appear to like it. We give full power to which ever bunch wins the most seats in Parliament. No one else can then block the legislative programme the "government" introduces especially if it was in their manifesto. Of course, things get a bit tricky when there is a coalition as we know only too well. In the UK, the Government is pre-eminent. OK, the Supreme Court can overturn a particular Government action but the Government can choose to change the law to fit in with the way that Parliament wants it to. I have always been struck by how anti-Government the average US citizen is compared with a UK citizen. So, coming to the FAA document, which I have read and understood based on plain English(!), it seems to be broadly in line with model aircraft operations as set out by the ANO, CAP 658 and the BMFA (which to a large part reproduces and interprets the law and guidance). Someone said that the 400 foot ruling would cause a problem. Well in the UK, you are limited to a ceiling of 400 feet if you are operating a model aircraft over 7 Kgs unless you have dispensation from the nearest Air Traffic Authority or in their absence the CAA. I would hazard a guess that this arose from the very limited weight and performance of the early experience with model aircraft in the UK where there was no height limit applied. The FAI still limits many classes to 5 Kgs although there have been relaxations for Scale and one other area which I forget. It's an interesting issue to determine whether prizes offered at competition can be deduced to be flying for hire and reward. I would say not, unless they were generous prizes, or pure monetary prizes, and all participants got a bite at the cherry just for taking part. I am unaware of how the UK regulates commercial flying schools where they are clearly flying for hire and reward - you have to hire the aircraft and pay the instructor. I don't know how the law applies to someone who is sponsored i.e. has some or all of the cost of the models he flies paid for by a commercial organisation. Is he flying for hire or reward? I don't know. The terrorism aspect, or even just criminal, may indeed result in the UK CAA taking another look at the FAA approach. Remember the ban on model aircraft operation, indeed light aircraft operation, during the London Olympics because of the fear of a terrorist attack. Sadly, I can see a little bit of that creeping into our legislation as time goes by!

I am a member of two clubs. At one, because we share the field with full size it is now mandatory to have a spotter to advise the pilot flying that a full size wishes to land or take off. The other task at one of the sites in this club is to control the flow of vehicular traffic across the patch. There are also pedestrians and horses/horse drawn vehicles to contend with! The other site has no such issues and you can fly on your own with the exception of gas turbine aircraft. So David, a "Yes but with some qualification" might have been a good additional category. I have to say, that the only time I've injured myself has been on my first visit to the first Club I joined when I reached over the prop to remove the glow clip! That resulted in a cut from the prop to the fleshy part of my palm. I didn't need any other help to deal with the cut, thankfully, and after an hour felt up to having my first flight with a suitably plastered palm - first aid kit in my car. Within a year of joining this Club they had to introduce a spotter as a full size gliding club moved onto the airfield and the spotter requirement has remained in force ever since.

Interesting that the AMA distances between flight line and crowd line appear not to differentiate between below 7 Kg and above and gas turbines. The BMFA recommendations, that are monitored by the CAA with visits to various shows, are: 30 mtrs (98 ft approx) between flight line and crowd line for up to 7 Kg 50 mtrs (164 ft approx) when above 7 Kg and gas turbine aircraft. So the AMA distance of 65 ft is 2/3 rds closer for up to 7 Kg and 1/3rd closer (approx) than any distance sanctioned in the UK. If the AMA is under pressure from the FAA, who might just look at what the CAA sanctions in the UK (yes, I know, highly unlikely since the US tends to believe that it is the world authority on all things) would these distances be reviewed?

Well done Germany. You saved the Brazilian President the embarrassment of shaking the hands of the Argentinians as the winners! Now, what are we going to do in the evenings? Oh yes, get back to finishing the next model - I'd almost forgotten!

Looks a really good job. Well done! As regards balance, don't forget an 8S pack can shift the CG around quite a lot to get things to balance - assuming you made provision for that when you built the fuselage!

Iqon There are a fair few that do this. If you look at this thread, you'll find some recommendations in the 110/120 size that cover three: Hacker, Jeti and Turnigy  - scroll about half way down the page to get to that post. There is also Castle Creations that provide such ESCs. These ESCs will go up to 12S lipos. The thread I referred you to has a lot of information on trimming and flying aerobatic manoeuvres which, if you have not already found it, which you may find useful. The thing to remember about ESCs is that the ones that serve the specialist precision aerobatic pilots (F3A class) provide useful things like prop braking that can be adjusted. This is not a brake on or off situation but rather a means of providing prop braking, like an ic engine, when flying a vertical downline. The Jeti is very easy to set up and is used by over 90% of F3A pilots for this reason. Edited By Peter Jenkins on 13/07/2014 12:48:09

Iqon, Powerbox and Emcotec are the two that I know of and both have a good reputation and are widely used in the F3A (aerobatics) world. I just use Hobby King Turnigy 2S lipos and have never (so far) had a problem with either the 800 mah or 1,000 mah batteries.

Iqon - you should be using a separate Rx power source when using an 8 cell lipo setup. For a start, you will not lose your Rx and servos if for any reason the flight pack malfunctions and that is a major safety issue. Secondly, you can connect up your Rx and do all your pre-flight checks without having the aircraft live as it would be if using a BEC facility. The other thing is that many ESCs at this level will be opto-isolated and won't provide you with a BEC facility anyway. Most aerobatic aircraft are fitted with a 2 cell lipo (usually between 800 mah to 1,000 mah capacity) and a combines switch/voltage regulator to drive 5 digital servos. I get 5 flights before there is only 40% remaining in the lipo and I then change to my second lipo. I have used a twin power switch and 2 lipos but I've gone back to a single power source now. However, I have seen a single lipo misbehave resulting in the loss of a top rate aerobatic model so, if weight is not an issue then the 2 lipo solution provides even more security.

You are missing the point kiwig - the pilot, who has flown this aircraft many times, should have been aware that all was not well, and closed the throttles thus removing the cause of the swing and enabling nosewheel steering and rudder to get the aircraft back on track - I doubt the aircraft would have swung into the crowd. Manifestly, he was not ahead of the aircraft as he should have been. As the old saying goes "better to be on the ground wishing you were up in the air rather than being in the air wishing you were on the ground"!

Well, that interview just about takes the biscuit! Clearly, he wasn't going to incriminate himself but he did a pretty good job of showing that poor maintenance may have contributed to the problem, Large aircraft like these are, in the UK anyway, classed as aircraft and should have a maintenance schedule. Also, there remains the issue of competency checks. Too often I hear cries of I've got a B and I shouldn't have to be checked. Well here, we had a guy flying in-front of the public who was slow to pick up that his aircraft performance was degraded and took the wrong actions. There is a saying that "a superior pilot uses his superior judgement to avoid getting into situations that require his superior skill to get out of!" As for HobbyKing putting their name to a whitewash of a serious accident - well, it beggars belief!

Notwithstanding the bubble in the aluminium, I go for double protection and use ordinary bubble wrap glued to the inside of the aluminium sheet to maximise protection. I hadn't thought of the handles though! Nice solution.

Rory I am not aware of any such insurance. If there were such a scheme, I suspect that the premium would be prohibitive. Be interested to hear otherwise. Peter