‘The Battle of the Lightweights’ May 18th/19th 2013
Report by Andy Housden
Carrier at Barton’s BASH now appears to be on the up! This event was originally one of the largest competitions of the season, but in more recent years (and along with the trends for most aeromodelling contest events) it has suffered something of a decline due to the recession and increasing fuel costs. It must also be said that the BASH weather in the last few years has not been particularly good at all. It is therefore very pleasing to report that the 2012 and 2013 events have seen a welcome increase in attendance – and those of you who didn’t come to the 2013 BASH missed an extremely enjoyable contest that experienced almost ideal flying weather! Consistent with Friday’s forecast, both days were somewhat overcast (more so on Saturday than Sunday) but both remained dry, warm and with a breeze that was no more than moderate at worst. Attracting eleven flyers, there was time for as many flights as each pilot wanted to undertake and both days were busy from start to finish.
Much like Carrier at the 2012 BASH, the top place was again fought out between Ian Gilbert and Johnathon Crabtree, resulting in some very high scores indeed – hence the title above! As at the Damyn’s Hall Airfield event a month beforehand, Ian played with two models – his relatively new electric Fairey Spearfish and his older SC 25-powered Westland Wyvern – before deciding that the Wyvern was better suited to the conditions, particularly on the Sunday where his first flight gave him a score of 247.1 points which just topped Johnathon’s own first flight score of 245.5 and looked to keep him in the lead. Never say never! Flying his silver Fairey Spearfish, Johnathon’s second flight, carried out in the knowledge of Ian’s score, managed to pull another 3.5 points out of the bag for a cost of a single warning and it was this score, 250.6 points, that finally remained the highest.
The differences between Johnathon’s and Ian’s models are also very interesting! Although both flyers’ models are below average weight, Ian’s Wyvern has a relatively small engine to ensure the model is kept as light as possible. The consequent reduction in top speed is accepted as a penalty worth the weight saved. Johnathon’s model, however, has a rather more honking .37 up front, so there a bit more iron bolted to the airframe! It’s the conventional wisdom that, given a full-point landing, a contest is won or lost on the slow run time, and in the vast majority of situations this is true – so it could have been expected that the 3.5 point difference between Johnathon and Ian was achieved by Johnathon squeezing out another half a second per slow lap. Not true! Ian’s slow run times were actually better – Johnathon won because, unusually, his fast run times more than made up for the difference. There still remains, therefore, a number of ways of skinning the cat, so the lesson here is this – all aspects of your model’s performance contribute to your final position!
The comments in the previous paragraph notwithstanding, the slow flight still remains the first area of model performance worthy of attention. Quite simply, the closer to the maximum attitude of 300 allowed by the rules that any given model can be flown, the longer will be its time for the seven slow laps – so improving the model’s ability to ‘sit up’ at 300 is always time well spent. This is not something aerofoil sections usually do willingly, so few models will behave this way without (often extensive) trimming and continuous pilot control. Flying as close to the 300 limit as possible, particularly when wind conditions vary significantly along the flight path, is therefore one of the major challenges in the BCD class.
Nigel Crabtree (along with plenty of other flyers, of course) has been experimenting with varying the tailweight on his Grumman AF Guardian to improve his ability to fly at the 300 limit. Part of the problem is, of course, that as tail weight increases, the model gets heavier – and also as the centre of gravity moves backwards, the model can often become unpleasantly unstable during the fast run. As tailweight increases and the model becomes able to fly at a steeper attitude, its reaction to wind conditions can also change. Nigel’s Guardian clearly preferred more windier conditions than Barton could provide and he found it difficult to maintain a 300 attitude around the whole of the circle during the slow runs. No complaints, though – after a number of flights, his best score of 207.8 points was still quite good enough for 3rd place!
Conversely, fourth place Andy Housden with 202.9 points flew his Short Seamew that happily sat at almost any attitude! If left to its own devices, the Seamew would actually continue to rotate backwards and stuff itself into the briny – and has on many occasions, as witnessed by all the airframe repairs. As the model readily exceeds the 300 limit, flights are often not warning-free – and weren’t this weekend. Unfortunately, the Seamew is rather overweight (all that glue!) so flight at even 300 has to be quite fast for it to stay up at all. There’s another moral here, of course – the lighter the model, the slower it flies – whatever the attitude.
Dave Holmes, flying his very smart Martin MO-1, found the conditions were very much to his liking and recorded some good scores, the best being 179.2 points and his highest for a long time – high enough for fifth place. Currently one of the fastest models on the circuit, the howling power unit is an old-ish OS 40 that Dave got for £10 at a swapmeet! On closer inspection, however, the motor actually looks like one of the high performance FSR types, a robust and powerful Pylon Racing design from the early 80s and no mean piece of kit. Looks like Dave got himself a bargain!
Whilst not part of the top scoring flights, in many respects the best landing of the event was that at the end of Fred Skinner’s first and single flight with his Short Seamew. Having already signalled for landing, the engine simply died on Fred about a quarter of a lap before the deck – but he still got the Seamew down to a flawless pickup of the No.3 wire! Deadstick landings are notoriously difficult – BCD models are generally fairly draggy beasts and whipping will only get you so far. Even presuming the remaining distance to the deck can actually be covered, you still have to heave the model round at the same time as getting your approach height, descent angle and radial position all exactly right – and there’s no going round again. It was a nice piece of work! Although Fred subsequently switched to flying his Martin MO-1 for the rest of the weekend, this was his best flight and the 173.1 points achieved got him sixth place.
Dave Cowburn, previously campaigning a nicely built Supermarine Seafire, tried his new Lockheed U-2 after deciding that the Seafire’s performance was unsatisfactory due to an overweight airframe. But the Lockheed U-2 spyplane? Yes! Although it’s not common knowledge that a variety of U-2 marks were hooked, this aircraft is actually eligible as a model. Hook development lead to special ‘strap-on’ packs that were used to navalise such aircraft when they needed to overfly parts of the USSR that couldn’t be reached from any of the land bases of friendly nations. The only other U-2 flown in Carrier before today was that built by Mike Welch back in the late 90s, and this used a very flimsy pair of ex-sailplane wings. The wing deflection was unbelievable (they flapped!) and if the pilot was a bit heavy on the stick, the wingtips would actually clap hands! This was extremely entertaining for spectators and completely in keeping with Mike’s propensity for experimentation, but the model had to be retired after the first flight! Dave’s U-2 was fortunately much more robust, being based on a profile version of the old APS stunt design by Frank Warburton, and though he flew it very cautiously – this was its maiden event, after all – he still achieved 159.3 points and seventh place.
Nick Ford was unusually on his own during the BASH as his dad had been temporarily hospitalised (to have his on-board power unit retuned). Hope you get well soon, George! Team Ford is a regular sight at Carrier events and its senior pilot is a retired employee of British Aerospace with a fund of interesting stories of experimental aviation engineering (ask him about the chickens they used to buy from Sainsbury’s to test aircraft windscreens against bird strikes!). Anyway… being on his own and involved in a zillion racing classes, Nick was unable to get over to the Carrier circle until late on Sunday – and without George to help prepare for flying, things were a bit rushed. This resulted in only two flights, the first of which ended after the fast run due to engine failure and the second terminated very abruptly when his Hawker Sea Hurricane came in slightly low for a landing and smacked into the ramp top, missing all the wires and getting rather bent in the process. The Sea Hurricane would live to fight another day, but the 92.4 point score (and eighth place) achieved was distinctly less than Nick’s best. Shame!
Ninth place John Whiteside, flying his very pretty Mitsubishi A6M Zero, had an unlucky succession of high and late approaches with his landings, missing the wires each time and producing an uncharacteristically low best score of 83.2 points. This masked some very respectable flight performances which were all the more impressive when it was revealed that John hadn’t flown Carrier for several years and had replaced his tried-and-tested three-line mechanical throttle with an electronic system that had an extremely stiff handle-mounted variable resistor, making rapid and minor power corrections almost impossible. The model has plenty of potential, though John is now likely to be reinstalling the mechanical system for future events!
Crewe’s Paul Stubbs and Adrian Thompson shared a Grumman F6F Hellcat (the free plan design that accompanies the Carrier Information Pack) – and therefore unfortunately also shared the model’s engine unreliability problems which produced a frustrating succession of ditches. Both Paul and Adrian are competent pilots with plenty of successful flights to their names, but despite much tinkering with the Enya 40, the motor never let Paul get as far as his landings and never let Adrian get even as far as starting any of his slow runs. Paul and Adrian therefore finished in tenth and eleventh places respectively, and although their results were a disappointment to both of them, they still obviously enjoyed flying Carrier at the BASH!