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1. What length lines?
You need to decide on a line length. Rule 1 permits any line length, but there will obviously be a range of lengths within which your model will perform best. The longer the lines that your model will safely fly on, the greater will be the time difference between your fast and slow runs and therefore the higher will be your final flight score. Unfortunately, the shorter the lines, the easier it is to make a successful arrested landing! Hence line length is invariably a compromise. If your engine is between .25 and .40 cu in, a line length of about 50ft should be quite workable for both learning and competition. With a bit of luck, you’ve already got a set of 50ft lines anyway. If you’ve got two sets (but they must be exactly the same length), then you won’t even need to make up your third throttle line, will you?
Once you can fly a Carrier sortie confidently at this radius, you can try longer lengths. Some pilots even carry several line sets of different lengths to suit different wind conditions. If you’ve just started flying Carrier and your model seems to be going alarmingly fast and/or pulling uncomfortably hard, don’t forget that you can always go slower without making up longer lines by either using a richer needle setting or fitting a larger prop or putting the normal prop on backwards, until your confidence increases. Don’t worry – it will!
2. What type of propeller?
The propeller you use will depend entirely on your engine. Too much pitch is counter-productive as this reduces model acceleration. Not only does this lengthen the standing-start-to-top-speed time and reduce your flight score, it also makes rapid recovery from slow flight stalls more difficult. Too little pitch, however, and the model won’t realise the maximum speed possible.
Sorry – but the only way to find the most suitable prop is by trial and error. Generally, the stiffer the propeller, the more efficient and therefore the better it is, but don’t forget that deck landings frequently break propellers and the flexible types survive much longer. It’s most sensible to start off learning to fly Carrier with the less expensive flexible nylon props (the yellow Kavan and the white Tornado types are good examples) and graduate on to the more expensive stiffer brands (eg: Graupner, Bolly or APC) later. It’s also worth experimenting with diameter, pitch, stiffness and blade shape purely from the point of view of noise reduction. There’s often a propeller which maintains model performance whilst producing a noticeable drop in total noise. Sometimes a prop of this nature has been known to even increase performance!
3. What sort of fuel and glowplugs?
Fuel doesn’t necessarily need to be anything special at all. Basic Carrier Deck is not a horsepower event. It’s much more important to have an engine that starts easily, throttles well, doesn’t blow plugs and lasts a long time! Use of nitromethane in the fuel has the advantage that needle valve settings are generally less critical, but high nitro percentages require lower compression ratios (usually involving cylinder head shimming) and can burn out plugs. Unless your engine is designed to run on high nitro contents, 5% or 10% of this power ingredient is usually enough. Some engines even specify straight fuel, ie: a plain methanol/oil mix.
Plugs, too, are not a major issue. Most engines used in BCD will behave well on a variety of types. However, low throttle periods can be extended during the slow run and in a very few cases the engine can become over-cooled and the fire can simply go out. The solution here is often a barred plug (usually called an R/C plug), or a plug that’s a hotter grade. Plug grades are measured by a number which increases with the hotness of the plug. Hotter plugs produce better idling but have an increased risk of burning out.
4. Getting ready to fly before the event
Here’s the order of preparation prior for a flight. This is the result of the collective experience (sometimes bitter!) of many Carrier pilots.
Several days before an event (or even before a simple practice session), you should inspect your model for wear and tear. Obviously much of this activity, though not all, will not apply to a new model. The life of a carrier model can be quite punishing and damage which goes unchecked often manifests itself later in the most inconvenient way, usually by spoiling a competition flight. Make sure all nuts, bolts and screws are tightened right up and where the threads are metal-to-metal, they have been treated with a thread locking compound such as Loctite. There’s no need to use anything stronger than a standard strength compound. The only exceptions are the cylinder head and crankcase cover bolts on the engine, which don’t normally require such treatment.
Ensure that all of the control system items are soundly fixed to the airframe or to each other, that they work properly without undue friction and that there’s not any excessive slop anywhere. This also includes the more obscure areas such as the horn (is it still firmly fixed to the elevator?), the elevator joiner (any flexibility between individual elevators?) and the elevator hinges (any visible tearing, splitting or parting of company?). Check the leadout cables in particular, replacing even the slightest fray with a complete new component.
Look critically at the airframe, notably at the wing/fuselage and tail/fuselage joints. These are classic sites for gradual fatigue cracking due to abrupt changes in material shape and stiffness which lead to stress concentration. The worst site for a profile-fuselaged Carrier model can often be at the wing leading edge due to the outward flexing of the fuselage under the relatively large weight of the engine. Check also for cracking round the hook pivot reinforcement and if the model is equipped with a hook release, make sure that it works satisfactorily and that all the components appear undamaged.
Test possible cracks anywhere on the model by flexing the airframe in such a way that a crack will open up. If it does, run a knife blade the full crack length to widen it slightly, flex it open again, fill the fracture with the runniest superglue you’ve got and release the airframe so the crack closes up again. If the Cyano is thin enough, capillary attraction will draw it into the very extremities of the crack and the entire fracture will be locked solid. Do this with even the tiniest of cracks – they’re tomorrow’s big ones!
The day before an event, use a previously prepared (and debugged!) comprehensive check list to make sure that nothing gets forgotten. Such a checklist can only be based upon your own experience and tends to grow with time – so start writing it now as it’s not a five minute job! This way, you can arrive at a flying event (reasonably) confident that if your flying is brought to an early end or prevented altogether by some failure, at least it won’t have been due to an avoidable mistake or simply having left a vital part of equipment behind.
5. Getting ready to fly at the event
Once you’ve arrived at an event, the first thing you should do is to speak to the Contest Director, pay the contest fee and find out the actual times of flying so that you know exactly how much time you have to sort yourself out and whether and when any practice flights will be allowed. Then find the line park or, if one has not been provided, a sensible position near the flight circle but away from the obvious walking routes. Unroll your lines and connect them to model and handle. Inspect every inch for frays and kinks and discard any line without a second’s thought at the sign of the slightest damage. This is where at least one spare line of the right length can be very useful. Don’t ever skimp this check – the consequence could easily be the complete loss of both model and motor. Just think of all your hard work at risk, as well as all the safety aspects. It’s just not worth it!
Now check to see if you’ve connected the lines up correctly. There are always going to be some times when you haven’t. Find a helper, preferably the flying colleague or even team mate who is the person likely to be helping you to start your engine/release your model. Get him to hold the model horizontally at eye level while you pull the lines tight and move the handle until the fuselage is in the normal flight position.
If this is one of your first flights, you won’t know what the normal position is, so assume the fuselage flies tangentially to the circle and move around to get the lines perpendicular to the fuselage. Make sure that a reasonably neutral handle position gives a neutral elevator setting. If it doesn’t, changing to a different length line connector to shorten or lengthen a single line may well solve the problem, but it may also alter the throttle setting. It’s best to either change the length of both elevator lines by shortening one and lengthening the other by equal amounts, or to move the elevator linkage at the horn if you have a quicklink mounted on a threaded rod. If you use a hook release, check that the elevator angle at which it works is unlikely to be reached by the movements required during normal flight and that the angle can be comfortably produced by a quick downward (or upward?) jerk of the handle.
Without the motor running and keeping the lines tight, open the throttle fully at the handle end and get your helper to look down the carburettor. Is the venturi fully open? Now shut the throttle. Does the venturi close right down as well?
Lack of full movement at one extreme usually means that your handle or bellcrank has reached the limit of it’s own travel before the throttle has. Whatever adjustment you make, be careful that you don’t simply transfer the problem to the other extreme of movement. If this is what actually happens, it means that the throttle arm travel is simply greater than that of the combined handle/bellcrank combination and the throttle arm throw needs to be reduced by selecting a hole closer to the pivot. The ideal is to have handle movements which are fractionally less than those of the bellcrank but slightly more than those of the throttle arm to ensure that the full range of throttle settings can always be obtained at the handle end of your lines.
Leaving your handle and lines on the ground, fill your tank and run your engine at a moderate speed for a minute or two. You should not check actual engine settings and throttle response until the motor has reached normal operating temperature. Most throttle types, though certainly not all, are set by first adjusting the engine for maximum speed and this is done at the full throttle opening simply by gradually leaning the mixture out using the needle valve. Once the peak revs have been reached, the setting should be richened by 200 rpm or so to allow for the slight leaning-out that happens once the model is airborne and subject to the load on the prop lessening and centrifugal force acting on the fuel supply. This is usually equivalent to no more than reducing the rpm by the smallest audible amount. Now shut the throttle and the engine should drop to a satisfactory idling speed.
Providing the engine will keep running, the slower the idle rpm, the better. A fast tickover is not a good setting since power is still being delivered and this may make it difficult to execute some types of landing technique which rely on a slow approach.
Let the engine idle for about 20 seconds and then bang the throttle open wide. The revs should pick up almost instantly to full or near-full power. Although some types of carburettor design are better than others in this respect, you really must have a quick response, particularly during the slow flight when you need instant power to pull the model out of the stall that you always have to fly so close to. Try this several times and if you don’t think the response is good enough, or if the idle is too fast (or even too slow), then the carburettor needs adjustment. Be careful here! Don’t undertake any adjustments lightly. There are many different types of carburettor, all of which vary in the way they achieve fast and slow mixture control and in sensitivity to adjustment. Unless you understand exactly what to do, it’s better not to fiddle unnecessarily at all. If adjustment really is needed, always refer to the manufacturer’s instructions, make only very small changes, and check for their effect each time. Best of all, get an experienced modeller to help you.
Once you have made any necessary adjustments to the carburettor, make sure you can get the same performance at the control handle end of the lines. Not even this double-check is a guarantee of faultless operation in the air, however. Airflow drag and turbulence can act on the lines and the model control system in peculiar ways, and such effects are not always predictable.
As the checking and adjusting of throttle movements and carburettor settings described above can sometime be a little involved, it is ideally carried out prior to a competition. Unfortunately domestic limitations on space and noise usually mean that most aeromodellers have to perform these activities at the actual competitions.
Right! Your engine is now properly set up and you’re happy with the model/lines/handle arrangement. Lay it all out again in the line park (if provided) or find somewhere safe where people won’t walk over your lines. No, you’re right. No such place! Anyway, have something to eat and drink, try and lose those pre-contest butterflies and wait either for an opportunity to practice or to be called for a competition flight.
Whether you’re indulging in a simple practice session or in a proper competition flight, your actions should be pretty much the same. Practicing is normally used to check the engine settings for the fast and slow runs and to see how the wind conditions of the day affect the slow run, as well as usually trying some slow flying and landings, as practice in these techniques is never wasted. It isn’t often that a practice session is used as a dummy competition flight, but there’s usually no objection to this provided that you can get someone to time your flight.
The Contest Director will probably do this if asked.
6. Flying Techniques
Right! Here’s what you should do for either a dummy or real competition flight.
Marking your landing position
Unless the wind has changed direction since the carrier was erected, the deck will always be exactly downwind. You’ll therefore take off and land with the wind on your back and this should help you by keeping the control lines as tight as possible during these two delicate phases of the flight. Get your helper to hold your model on the deck centreline right in the middle of the arrester wire area whilst you position your handle so that the lines make a right angle with the deck at this point. Now pull the lines tight and guess at the sort of stance that you’ll adopt during the final part of the touchdown. OK: that’s your landing position. You’ll need to mark this in some way for reference. You can place something under one foot so that you can position yourself by feel during the landing (a rubber car mat is a favourite), or you can use a visual marker for either your foot position or for the actual position at which the handle needs to be. This tends, rather obviously, to be something fairly bright and usually pinned to the ground so that it doesn’t get kicked out of position. There is often a slight tendency in pilots to pull back on the lines during the final part of the landing approach (probably due to the stress of the moment!), so if you want to allow for anything untoward, assume that this will happen to you and position your landing marker up to (say) 4-6 inches closer to the carrier. This reduces the likelihood of you pulling your model off the inboard edge of the deck and spoiling what might otherwise be a perfect landing.
Setting up the pilot’s circle
Rule 8 states that all flying must be carried out from inside a 10ft diameter pilot’s circle. This is principally to constrain pilots from walking huge circles during their slow run in order to increase their flying radius and therefore their slow run time. Because Rule 1 allows any line length, the pilot’s circle has to be moveable to suit the flying position of each competitor. The circle is therefore a large springy hoop made up of brightly coloured drain rods, as this can be easily moved by hand but is difficult to kick out of position, maintains its circularity well and can be seen by both the pilot and the Contest Director. It can also be readily felt underfoot and and this avoids the need to look down during the slow run when a pilot’s attention tends to be fixed on his model rather than on his own position.
You must place this circle to cover all your flying positions, so drag it over from where it was used by the previous pilot. A favourite configuration is to use the edge of the circle nearest to the deck as the landing marker itself, since it can be both seen and felt easily. This also means that you don’t need to worry about markers of any other kind. Set up like this, the actual centre of the circle is therefore some 5ft further away from the deck and this can sometimes be a help during a slow run at low altitude, since it means that your model is a lot less likely to inadvertently collide with the carrier! Such a circle position is usually quite acceptable for takeoffs, but you should confirm this by getting your helper to lift your model out of the arrester wires and place it on the deck centreline just forward of the last wire. This is the normal launch position as it gives your model the maximum unobstructed length of deck from which to take off. Make sure that you can comfortably handle the model at this position without being likely to step outside the circle. OK? Then get your helper to pull the model over to the outboard edge of the deck (which is actually where you will start it up) and put your handle down on the ground.
Starting your engine and final pre-flight checks
Walk back to the deck, make sure your hook is latched up (if you have a hook release fitted to your model) and your tank is full. More than a few competition flights have been spoilt by running out of fuel.
If you start your engine by hand, always use a chicken stick or finger. With modern props sometimes having razor sharp edges, even the most good-tempered engines can sometimes turn vicious, particularly if you overprime or mismanage the process due to nervousness. Better still, use an electric starter. There’s no shame in it, you know…
With the engine running, check for full revs but don’t change the needle setting you arrived at earlier on when you were in a much less fingers-and-thumbs state unless it really sounds wrong or the weather conditions have become materially different.
Now walk out to the handle – don’t run. Use the time to wipe any oil off your hands with a spare rag you should always keep in your pocket. Keep calm. Tell yourself that although this flight is important, it’s not that important. There’s always the next flight if you make a mistake. Or the next competition. Or even next year! Pick up the handle, thread the safety strap over your wrist and stand inside the pilot’s circle. Why not even pause to admire the scenery? Try to rattle the opposition with your display of (outward!) calm. It might not fool them (they’ll be trying to do the same later…..) but if it helps your own confidence, it’s always worthwhile. Pull the lines taut and your helper should slide your model from the starting position across the deck to the centre line. Open the throttle and the engine should pick up to peak revs. Shut the throttle and it should drop instantly to a slow idle. Apply brief bursts of throttle and the response should be near instant. If you detect any problems now and this is a practice flight, nothing’s really urgent. Don’t try to fix anything but the simplest defects whilst you’re on the deck. Just abort the flight and sort the matter out away from the hurly-burly of the circle. If, however, your flight is official, you will forfeit an attempt if you withdraw once you have started the engine. Any problems now are therefore urgent and you will have to decide whether the problem can be fixed fairly quickly. Even if it can’t, or you simply don’t know what’s gone wrong, you actually now have little to lose by carrying on in the hope that the fault might simply disappear or have little real effect on flight performance. Let’s hope that everything’s actually OK, so it’s time to go for…..
The take off
Check that your flying area is clear. Even though you may be making a competitive flight in an official event run by a Contest Director, you yourself still have the legal (and moral) responsibility to fly safely – so never forget this vital action.
Apply full throttle and set your elevators to neutral or slightly up. Although only experience will tell you exactly what elevator setting is required for the best takeoff, you certainly should not require a lot of up elevator as this will cause a lot of drag and slow the model down just at the time when it needs the greatest acceleration. If your model won’t get off the deck without fistfuls of up elevator, you need either a more powerful engine, less propeller pitch, shorter lines, less nose heaviness, some combination of these – or, ultimately, a better model! Having previously arranged an obvious release signal with your helper, give it and be prepared to step back gently to maintain line tension as the model rolls along the deck. Don’t pull back unnecessarily, though – this can easily drag the model off the inboard edge of the deck before flying speed is reached, resulting in an inevitable tumble and the waste of an attempt. The model should leave the deck in a shallow climb, accelerating all the time. Gently level off at about 10ft altitude and bring the handle into your body. The final flying height isn’t critical, providing you don’t exceed the limit of 20ft required by Rule 8. Everything OK? Good. You’ve now given your model the best chance of accelerating to flying speed from a standing start in the shortest time possible, and you’re now into…..
The fast run
The object here is simply to fly 7 laps from a standing start as quickly as possible. Continue to keep the handle against your body and pivot on the spot to minimise the model’s true flying radius and consequent lap times. It doesn’t matter where in the pilot’s circle you stand, but it would be prudent to move to the half of the circle which is the furthest from the deck to avoid possible low level collisions with it!
Continue to fly at about 10ft altitude with the flattest flight path that you can achieve. An undulating course due to excessive elevator corrections will simply slow the model down and increase your lap times. Don’t fly too low as this can cause problems: sudden wind gusts can knock you down into the ground as well as into the deck and it’s even possible to end up flying into the ground on the uphill side of a sloping site if you’re low enough. Incidentally, for ground, read water – as everything but the carrier is deemed to be the sea and touching the water with any part of the aircraft is considered ditching. This will always result in disqualification of the flight. Nor should you fly too high (ie: above 20ft) or whip your model to improve it’s speed, since the Contest Director is entitled to disqualify your flight for these rule infringements.
Don’t be surprised at the strong line pull exerted by your model. A typical 2.5lb model circulating at (say) 70mph on 50ft lines will produce a 16.5lb pull, and that’s quite an armful! As your model, lines and handle combination should be capable of withstanding a pull of 15 times model weight as required by Rule 3, there’s no need to throttle back in alarm. Just hang on and wait for the fast run to end. Don’t bother to count the laps as that’s not your responsibility.
The Contest Director will audibly signal the end of the 7th lap, usually by a horn, whistle or loudhailer. Only after this should you slow down by gently reducing the throttle setting to a cruise and perhaps relaxing. A bit, anyway!
Well done – you’ve now completed your fast run in the shortest time possible. No part of this run demands the extensive practising of special techniques, so beginners and experts alike should achieve success here without undue difficulty or delay. Now for the next part……
The slow run
The object here is simply to fly 7 laps as slowly as you can without ditching the model. This is where contests are usually won or lost, although much of what you can achieve is governed by the wind conditions as well as your own piloting skills. Slow run times on a windy day are invariably lower than those achieved in a flat calm, but since the wind generally affects all competitors in the same way, no-one has a particular advantage.
You can choose to execute your slow run from a single point in the pilot’s circle, or you can utilise the whole of the circle by walking round the edge to maximise the model’s true flying radius and consequent lap times. Most pilots seem to stay in one position, as they’re usually concentrating so hard on flying their model just above the stall that they haven’t got any attention left to spare for the act of walking!
The best single point to fly from is difficult to recommend, although it probably lies somewhere between the actual centre of the pilot’s circle (from which position you’ll have 5ft to use in any direction whenever you need to step back to regain line tension) and the edge of the pilot’s circle furthest from the deck (from which position you’ll have a maximum of 10ft to step back to regain line tension when your model is directly upwind and therefore in the worst position for maintaining line tension). If you choose to walk around the edge of the pilot’s circle, you will always have 10ft of space behind you in which to regain line tension, but if you step outside the circle just once, the Contest Director will disqualify your flight. Whatever you choose to do, don’t forget that you can also extend your arm wherever you are. This will give you a useful increase of 2ft or so in both your flight radius and your line tension recovery distance. However, the foregoing is all very well, but in practice the apparent advantages of each technique are often ignored in favour of a comfortable flying stance which allows the pilot to concentrate on getting the best out of his model without worrying about what he’s supposed to do with his feet or arm! Hey ho…
The most efficient form of slow flight is one in which model airspeed is kept just above stalling speed no matter what the wind conditions. If the slow run is made in a flat calm, then there is no wind to affect the model and airspeed is simple a function of the throttle and elevator settings, with airspeed and groundspeed being identical.
In theory, under these conditions, the throttle can be gradually closed and the elevator angle gradually increased until the model is wallowing along just above the stalling speed and just below the stalling angle of the wing. The controls are then left at these settings and the model flown for the full 7 laps without further adjustment. This equilibrium is the ideal and will give the pilot the longest slow run time that is possible – the model will simply fall out of the air if flown any more slowly or at any greater angle of attack, and if occasional bursts of acceleration or reductions in angle of attack are made, no matter how briefly, the average speed of the model will always rise above the minimum value possible.
The presence of any wind can obviously have a big effect on this simple technique. Once a flight is subject to wind, the circular flight path means that the model is constantly changing direction relative to the wind and therefore to the wind speed. This means that the model’s true airspeed varies cyclically throughout every lap.
However, model speeds are, of course, judged not by airspeed, but by groundspeed, as the ground is the only reference available to the pilot. So when there is wind, the resultant variation in actual airspeed as the model flies around the circle means that the pilot has to constantly adjust both the throttle and elevator settings to vary the groundspeed in such a way that the actual airspeed itself is kept as close to the stalling speed as possible. Got that…..? Since the pilot does not have an airspeed indicator, he can only judge stalling speed by model behaviour. A gusty wind that continually changes direction will obviously make the pilot’s work even harder….
For your early flights, it is much easier and more prudent in slow runs to opt for a constant groundspeed. The speed you should use will be governed by either the airspeed needed to stay just above stalling speed when the wind is directly behind the model (ie: true airspeed is at it’s lowest value), otherwise known more graphically as the ‘downwind hole’, or the speed giving minimum acceptable line tension when the model is directly upwind.
Whichever of these two conditions is more critical will determine the constant value of groundspeed at which you should fly. Once you are confident with this type of setting, you can (on the same flight, or on the same day, or sometime during the same season – depending on your confidence!) then start to reduce groundspeed on other sectors of the circle. The best part of the circle to try here is undoubtedly that in which your model is flying directly into wind, since the true airspeed is at it’s highest value here. At this point, actual groundspeed may be reduced to the minimum value possible . Once beyond this sector, you should quickly get back up to your original constant groundspeed setting in readiness for the wind-behind-the model/minimum line tension sectors. Once you have mastered changing throttle and elevator settings from one regime to another and back again during each lap, it’s only a matter of practice to achieve this continuously at all points around the circle. The experience that you build up will provide you with the skill necessary to achieve the slowest flight for any conditions that the Weather God can throw at you!
As ditching, no matter how momentary, causes instant disqualification, it is a powerful reason for not flying too low during the slow run since you have minimal recovery height from a stall. It’s also a very good reason for constructing a hook release on your model and keeping the hook latched up until you need it for landing. A typical hook dangles some 6 inches lower than any other part of a model and, when lowered, simply reduces your vertical recovery space.
Don’t think the Contest Director won’t notice if you drag your hook through the grass (sorry – wave tops) – a hookful of grass cuttings and a subsequent disqualification is not uncommon!
The slow run clearly requires a certain self-confidence, piloting skill and familiarity with the characteristics of a particular model. Though this is entirely achievable by all aspiring pilots, beginners should not expect the sort of instant success here that they will find easy to achieve in the takeoff and fast run.
Except for the actual landing itself, a good slow run time is usually the main contributor to a high overall score and it is worth considering how to improve your model’s performance in this area. The scoring system works on simply the time difference between the fast and slow runs and not the actual speeds themselves. There can therefore be only a small amount of room for improvement in the fast run time, since the fastest possible time is zero seconds (!). The amount of room for improvement in the slow run time is, however, effectively limitless. It is therefore undoubtedly better to set your model up for maximum low speed performance, even if this is at the expense of its high speed capabilities. The scoring has been deliberately set up this way so that the use of expensive and high performance speed engines is discouraged in order to make participation much easier for ‘ordinary’ aeromodellers.
There are several ways to boost your slow run time:
If your model is equipped with some kind of adjustable leadout guide, you should try various rearward settings. The closer the leadouts are to the trailing edge, the more the model will be forced to yaw out of the circle and the better will be the line tension at low speed. Obviously the line tension will also be higher during the fast run, but this is the (slight) price that has to be paid.
Try increasing values of outboard tip weight. It’s sensible to provide on your model a simple hardpoint onto which various weights can be screwed. Good weights to use here are the lead buttons used for sewing into and weighting down the bottoms of curtains – obtain these from good hardware shops or drapers. The greater the outboard tip weight, the more your model will fly banked out of the circle and not only the greater will be the resultant line tension at low speed, but there will be less of a tendancy for the weight of the control lines to roll the model inwards during speeds close to the stall when wing lift, and hence stability, is marginal.
Try tailweight. Many models end up being built with some nose heaviness. There is nothing intrinsically wrong or uncontrollable with this provided that it isn’t excessive, but a nose heavy model can often require fairly powerful (ie: large) elevators to get it to ‘sit up’ at angles of attack that are close to the stall. Since it’s much easier to add weight than it is to increase the size of your model’s elevators, experiment on a trial and error basis with different values of weight attached to the extreme tail. Although you certainly don’t want a tail heavy model due to the accompanying instability, it’s worth trying tailweight in small increments to see if this improves the model’s ability to fly closer to the stall. Again, it’s useful to provide on your model a tail hardpoint to which can be screwed the same sort of weights used on the outboard tip.
The slow run cannot start until you have signalled your readiness to the Contest Director. Take advantage of this and give yourself time to recover from any takeoff and fast run nerves. You are entitled to fly for as long as you want before signalling, so use this to familiarise yourself with the wind conditions and to set the model up for the slow run as carefully as you can.
Until you have given your signal of readiness, your activities so far remain classified as an attempt, not an official scoring flight. Rule 5 allows three attempts out of which you can make a maximum of two official flights – so this means that you effectively have a ‘spare’ attempt which you can abort in the early stages if you’re not happy about anything, eg: unsatisfactory fast run, poor engine setting or throttle response for the slow run, model misbehaving, etc. If you’re satisfied with your performance up to now, make your signal and thereby convert your attempt into an official scoring flight. Your signal can be anything, but a raised arm is common and this needs no prior arrangement with the Contest Director. If you intend to use anything else (a nod or a shout, for instance), it’s advisable to inform the CD so he knows what to look out for.
Once you have given your signal, the next time your model flies past the position from which you made your standing start, the Contest Director will start to time the run. To gain the maximum benefit, your model should already be flying as slowly as possible before you give your signal. Once the run has started, you will probably be sufficiently busy to be completely unable to count the laps – so don’t even try. As before, lap counting is the CD’s responsibility. In fact, if you have enough concentration to spare for lap counting, you probably aren’t concentrating enough on your slow flying! Think only of the wind strength and direction, fly as slowly as you can according to the advice above and continually watch your model behaviour so that you can spot an approaching stall and take corrective action before it happens.
Whilst every aircraft that takes to the air risks destruction, if you are making a practice flight prior to competing, you should not risk your model unduly. Damaging it or even writing it off during a competition is bad enough, but doing this during practice and therefore being subsequently unable to compete is obviously a major waste of the time and effort of travelling to a contest. Save the sh*t-or-bust flying for your bid for 1st place! Furthermore, as you get at least two official flights to record scores, your first official flight should be relatively conservative and used to familiarise yourself with the conditions, your model, the terrain and the deck. Obviously, practising (carefully!) before the competition starts will get you further along this desirable road, but you are nevertheless advised to leave the major risk-taking until your second (or last) official flight in case the result is sufficient damage to prevent further flying. If your first flight has produced a reasonable score, you can try to improve this during your second flight when you have a much better idea of your chances of placing well in the contest.
It is not uncommon for the 7 slow laps to seem endless! Just keep on flying as close to the limit as you can. Remember that some contests have been won by as little as 0.1 of a second and that sort of difference can only happen in the slow run. Once the slow laps are completed, the Contest Director will signal to you in the same way as he did for the end of the fast run. Only then can you breathe a sigh of relief! But not too big a sigh, because you’ve still got to do…..
To stand a chance of placing well in a competition, your landing must be a 100-pointer. If you read Rule 10, you’ll see that this means an arrested landing with your model stationary in the correct attitude for it’s wheel arrangement. ‘Arrested’ means that the model must have been stopped by picking up one (or more) arrester wires with it’s hook – not with it’s wheels, propeller, wing or anything else. ‘Correct attitude’ means that aircraft with tractor (ie: tailwheel/tailskid) or tricycle undercarriages must be left standing on all 3 wheels.
There are a number of different techniques that can be used to get a model down onto the deck to pick up an arrester wire. As there is no ‘right’ method, it is worthwhile practising all the variations and selecting the one at which you are most successful. Landing on the carrier must be done as slowly as possible, consistent with maintaining adequate control over the model’s flight path. A few pilots prefer to maintain their slow run speed after the timing has finished and they simply lower their model’s hook, move over to their landing position marker, signal their readiness to land and approach the deck without any change in the throttle setting. The majority of pilots, on completion of their slow run, will instead open the throttle and execute a few laps at a higher speed and altitude, during which the hook is dropped and the pilot walks over to his landing position marker. Only after this is the model throttled back to the final approach speed
There is some merit in each style as the former avoids the need to re-establish a slow speed and the latter helps both to clear any unburnt fuel residue that the engine has accumulated during the slow run and to warm it up again, giving a more rapid throttle response if the landing has to be aborted and the model needs to overshoot. It also gives a safer height and better line tension during the twitch of down elevator required to release the hook and the walk over to the marker. It may even be the mental equivalent of the pilot ‘stretching his legs’ after the strain of the slow run, enabling him better to switch his concentration to a different type of flying! This latter technique is recommended for beginners to BCD.
Once you have dropped your hook and moved to your landing position marker, set the throttle so that the model is flying slightly faster than it was during the slow run. This extra speed will give you more airflow over the elevators and therefore a better control response, leading to greater flight path precision. This speed will generally be suitable for all the major landing techniques used by pilots and described below.
The Constant Height & Speed Approach.
Otherwise known as the ‘Creeper’ technique, this method requires the model to be flown round at a constant low speed and constant height at or just above the level of the deck, so that the dangling hook picks up an arrester wire at, you hope, the first overflight of the carrier. It has worked for some pilots in the past, but it is a good model and an extremely good pilot that can fly at a constant height of about 15 inches. This technique is also difficult to execute on a sloping site and, anyway, there is little margin for error, being particularly hard on the model if the flight path ends up below the top of the stern ramp. Wham!
The Power-on Diving Approach.
Otherwise known – somewhat alarmingly – as the ‘Sudden Death’ technique, this method is rather different. On preceeding laps, the model is flown at a similar slow speed as before but at the much higher altitude of between 10ft – 15ft. On the final approach, using the end of the carrier as the visual reference, the model is deliberately aimed downwards at the stern. Just before arrival, substantial up elevator is then applied to flare the model out into the middle of the arrester wire area. This type of landing obviously requires a robust undercarriage since the impact forces can be considerable, but the approach need not be so precise as the Creeper.
There is also a common variation to this method which uses a similar airspeed but an approach altitude that is much less (typically 5ft -6ft) and the model is again dived at the deck. If the dive angle is sufficiently flat, many pilots even omit the landing flare and aim straight at the arrester wires so that the flight path effectively intersects the deck at a perceptible angle. This certainly requires a robust undercarriage and is apt to break fragile propellers on occasion, but it is one of the more popular methods and is probably the closest equivalent to the landing approach of full size modern Navy jets.
The Power-off Descending Approach
On preceeding laps, the model is flown round at the usual constant slow speed, but now at a constant height of 3ft – 4ft. On the final approach, using the carrier as a visual reference again, the throttle is shut at a chosen point and the model allowed to adopt its own shallow-angled descending glide path. With experience, the pilot will know the correct distance from the end of the stern at which he must close the throttle, and the model will then sink down into the middle of the arrester wires. This type of landing is the gentlest of all and with practice it is even possible to stall the model onto the deck. However, in the final moments, the amount of corrective control available can be minimal due to the very low airspeed of the model. The main area of control that the pilot has over the landing is therefore in the selection of the position at which he closes the throttle. If the flying height is increased or the model speed is faster, the distance of this shut-off point from the stern will increase, and vice versa, so accurate prediction of this point can in practice be quite difficult.
There is a slight variation to this method which can improve model control during the actual descent. The pilot either flies the model at the same height as before but at a very slightly higher airspeed, or flies the model at the same airspeed as before but at a lower altitude (about 2ft). In both cases the model has less time to decelerate before it reaches the deck and therefore spends more of its time at a higher speed. This gives better elevator response during the descent and last second corrections to the flight path are easier to make. As the angle is usually very shallow, there is normally no need to flare the model out and it is simply flown straight at the middle of the arrester wires.
Having established your model at the approach speed, descend to the flying height required by your chosen landing technique and make a number of passes over the deck so that you become familiar with the general approach to the deck and the speed of appearance of the carrier in your left hand peripheral vision. As you rotate with your model, keep half an eye on your landing position marker and note exactly where you’ll have to be during the final approach itself. OK? Now you’re ready! Make your signal of readiness to the Contest Director in the same way as you id before your slow run and get ready to land at the next approach. Here you go!
At the moment of hookup, try to remember not to pull back on the lines as it’s so easy to drag the model off the inboard edge of the deck and lose all your hard won landing points. Whatever landing technique you’ve used, you’ll find that the moment of successful hookup is usually surprisingly sudden. So keep still for a second, let your thoughts catch up with you and savour the moment. You’ve earned it! If your engine is still running (not unusual), keep the control lines tight so that you can ensure the throttle is either closed down or remains shut until your helper can reach across the deck and stop the engine. Now you can collapse in relief!
If you failed to make an arrested landing, don’t despair. If you landed your model right in the middle of the arrester wires but still failed to pick one up, that’s quite unusual and really unlucky. Providing the landing impact wasn’t severe enough to ground the propeller and either break the blade or stall the engine (and that’s obviously a recommendation for those techniques which produce gentle landings), open the throttle wide. Since your model will still have some forward motion, acceleration back to flying speed in the remaining deck distance should be easier than the standing start. However, an unsuccessful landing is far more likely to have been caused by excessive approach height and/or late reactions on the final approach. The result of both of these classic faults (and they’re so easy to make…..!) is either a touchdown position beyond the arrester wires or a complete overshoot of the deck altogether. If you have touched down, you should open the throttle wide as before and again hope that your propeller is still in one piece and your engine’s still running. Unless your model is particularly under-powered, you’re unlikely to have any trouble getting off the deck and back in the air.
Once you’re airborne after any sort of deck contact, you should reduce the throttle setting as quickly as possible and get back to your landing approach speed and height. In the case of a complete overshoot, you still need to get back to your landing speed and height as quickly as possible, though this will probably be rather more straightforward unless you have inadvertently applied full throttle in reaction to the actual overshoot itself.
Remember that you will lose 5 points for each lap flown after your first unsuccessful landing , so you can’t afford the luxury of several extra laps to set your model up again. You have to decelerate back to the required speed and stabilise the model at the correct height in rather less than a lap, as well as making sure that you’re back on your landing marker during the next approach. It’s a busy time! Fortunately, there’s no need to give any further signals of landing readiness as the original signal was the only one required. Just concentrate on your approach and try to ensure that the cause of your first aborted landing is not repeated this time round. Even if it takes a number of attempts before you hook up, you should nevertheless persevere as this is all valuable experience and character building stuff!
Congratulations are always in order for a successful hookup and pilots will frequently receive applause for their efforts from fellow contestants (but beware – arrested landings are also highly addictive. Once you’ve achieved one, you’ll want all of them to be the same!). Finally, untangle your arrester hook from the wires and get your helper to assist in moving your model and lines back to the line park or pitting area so that the flying circle is clear for the next competitor or practise flight. Make a note of your final score, no matter how well or badly you seem to have done.
Although you are obviously less likely to achieve top scores as a beginner (though it certainly has happened), the improvement that you will see in your personal best scores as your skills improve can be as exciting to you as a good competition placing can be to a more experienced pilot. As your own experience increases, better scores will result not only from improvements in your flying abilities but also simply from your growing confidence both in your model and yourself.