Escapade Kid
Transcription
Escapade Kid
flight test New KID on tHe bLock David Bremner takes the Kid Escapade for a spin 20 Microlight Flying Anyone thinking of buying a sub-115kg ultralight has recently been pretty much spoilt for choice. The fact that they don’t need to demonstrate compliance with an airworthiness standard to sceptical and litigation-shy authorities has encouraged many importers and manufacturers into the market. As yet, however, the market has responded patchily, the runaway best seller to date being the Flylight Dragonfly, the flexwing trike with retractable wheels featured last issue. But people are starting to put their hands in their pockets for a fixed-wing model too. The Kid Escapade attracted a lot of interest on the Escapade Aircraft stand at the November SPLASH, and continues to do so, so recently we went to the historic airfield at Old Sarum to see what all the fuss is about. The aircraft, G-OKID, was the one successfully auctioned at SPLASH and is now the property of successful bidder Vince Hallam. And although one might be tempted to criticise Escapade proprietor Terry Francis for auctioning his Kid into slavery, the youngster looked happy enough sat on the grass in the weak February sun. He (and it’s unquestionably a he) actually reminded me more of a puppy, sitting up, tongue protruding from the cowl, cocky tail feathers wagging as he strains at the leash and wants to be up and away. He’s small and neat, and you just have to give the cowl a pat as you go past. But enough of fancy. You want hard facts from a steely-eyed reporter, not romantic rubbish. The Escapade’s family history can be traced back to pre-war aircraft like the J3 Piper Cub, with its high wing, welded steel- tube fuselage, light weight and low power. The first direct ancestor was the Avid, which introduced the wonderful simple folding wing concept, to be followed by the Kitfox and thence the Sky Raider via the Easy Raider and so to the two-seat Escapade. The Kid is actually something of a throwback, being derived from the single-seat variant of the Sky Raider which has been available in the US as a Part 103 machine for many years. The wing has remained unaltered through Sky Raider, Easy Raider and Escapade, and the same basic wing is used for the single-seater, though the spars are of lighter gauge tube in order to keep the weight within bounds. But the ply ribs and control surfaces are common to the Kid and his elder brother. The fuselage, undercarriage and tail feathers are welded steel tube, though clearly reduced in scale, and the option to switch from nosewheel to tailwheel isn’t possible within the weight limit. There is a single hard point next to the spar attachment, however. ‘What’s that for?’ I asked Terry. ‘Floats,’ came the answer. ‘In the US, there’s a weight allowance for floats on Part 103. Maybe we’ll get it here in time.’ Oh, yes please… The design was loaned to Dr Guy Gratton and a team of his undergraduates at Brunel University to analyse, and they confirmed that it met the structural requirements of BCAR Section S. Load testing of the wing had already been done in the US and analysis confirmed original findings. With all sub-115kg machines, weight (or more strictly, lack of it) is of the first importance, and in this case, the wing area (10.5m²) reduced the maximum allowable empty weight to 105kg. w April 2009 21 flight test w SmAll and NEat, the kid is like a puppy, sitting up, tongue protruding, tail wagging as he strains at the leash. You just have to give the cowl a pat as you walk past 22 Microlight Flying Terry wasn’t convinced it could be done, so the build process was fraught with uncertainty. Nevertheless, there were a couple of kilos to spare on completion, thanks in part to the use of the pre-impregnated Oratex fabric recently developed in Germany, and also to the use of the Hirth F33AS single-cylinder two-stroke with belt reduction drive, which offers 28hp from only 21kg installed weight. Having achieved this major success, there are a number of ways in which the build might be lightened, and the effective lifting area increased, which will open up possibilities for other engine fits. Other points of note in the construction are the bungee suspension on the main undercarriage, similar to the Escapade. The tailwheel is of the shopping-trolley variety, with spring connections to the rudder, which means it’s non-castoring. G-OKID is fitted with optional brakes, individually operated via hand levers on the stick. The windscreen extends over the roof to give maximum visibility. Another option is the front-hinged door(s) which flop down conveniently when open, and the top-hinged windows. These will, I suspect, be popular additions in the UK. The seat is well-upholstered but non-adjustable, and the floormounted stick operates the ailerons via cables and the elevator by pushrods. Floor-mounted rudder pedals operate the rudder via cables. One slight surprise is the flaps on the wings; necessary for the Escapade, but surely not for the Kid? ‘No,’ says Terry. ‘They’re needed to allow the wings to overlap when they fold, and it was easier to retain commonality with the Escapade.’ There’s a single 20 litre tank in the starboard wing; access is much easier than most high-wing aircraft, and if you think it sounds on the small side, bear in mind that’s probably enough for about 4h based on predicted fuel consumption… At the back of the cabin, there’s a sudden dip in the top of the fuselage to accommodate the folded wings. The Escapade has a removable turtle deck to fair in the gap, but because of the narrower fuselage width and the fact that the rear fuselage changes to triangular cross-section, it’s too small to be worth bothering with on the Kid. The tail feathers are of flat section, made of fabric-covered steel tube and cable-braced. They seemed admirably rigid. The Oratex covering is brand new, and G-OKID is probably the first aircraft in the UK to fly with it. Developed in Germany, it is intended to replace conventional aircraft coverings, coming pre-impregnated with all the sealant, UV protection and colour, so you only have to attach it using the heat-sensitive glue, and shrink it with an iron. Anyone who’s played with the various conventional covering systems will know that the skill required – and the overpowering smell – tempt many people into getting it done professionally. Oratex isn’t cheap, but Terry reckons it’s comparable to paying to have the other systems applied – and it’s lighter. It comes in a variety of colours, and you can paint it if you wish, though this will add to the weight, of course. The surface isn’t as shiny as with full two-pack paint, but it’s claimed to be as durable. You would need to keep an eye out for stains, though, and remove them using proprietary cleaners. The fabric tension on this aircraft wasn’t as great as I would have expected, but Terry said he’d not used full tension in deference to the light weight of the frame. Oratex has been approved by the LAA for wing loadings up to 9 lb/ft² (such as the Sherwood Ranger), so it can be used with some confidence on the Kid. So much for the look round. It was time to see what it was like inside. The wing is below my eye height, so you might have expected entry to be a bit of a challenge. Not a bit of it. Sit on the seat first, then swing your legs in. Couldn’t be much easier. And, Tardis-like, there’s tons of room inside, even with the door and window shut. I’m 6ft 3 in, and chose to wear a crash helmet, together with multiple layers of clothing against the cold – and there was plenty of room, both sideways and on top, and the diagonal bracing, which I thought might get in the way, didn’t seem to at all. There’s a minimal instrument panel, allowing loads of knee room. The view out is excellent forwards and sideways. Despite the upright engine configuration, the cowling doesn’t impinge on your line of sight at all, and you can see the horizon ahead even with the tailwheel down. The throttle and trim lever fall conveniently to one’s left hand, and the instrument fit was suitably minimal. The four-point harness was easy to secure and adjust, though there’s a booby prize for those who tighten the shoulder straps before realizing how long a stretch it is to the starter handle! To start the engine, flick the choke on (it’s got a convenient over-centre catch so you don’t have to hold it on), close the throttle and wrap your fist round both brake levers on the stick while you lean forward to the recoil starter handle on the floor. It went second pull, and settled down to an easy chatter when the choke was put in. Tighten the shoulder straps, and start your preflight checklist. With the windows shut it isn’t possible to see behind you to check the control movements, but opening the window would be straightforward. Taxiing is very easy with the brakes, and in all but the strongest winds pretty straightforward without. For operation off a grass strip, I suspect that they may not be necessary. Into the playground With power checks complete and the trim set somewhere in the middle of its range, I lined up and opened the taps. Downsizing from 80 to 28hp feels strange at first, but you don’t have time to think about it before you’re off. Terry quotes 50m takeoff distance and I achieved that on my first try with only 6mph headwind – and I’m no featherweight. If you’re concerned about flying a tailwheel, this is the beastie to give you confidence; simply hold the stick in a neutral position, and you’ll be airborne before you’ve thought about it. The rate of climb was positive, and because of the slow speed, the angle of climb was phenomenal. I’d reached circuit height before the end of the runway, and turned south to explore the Kid’s capabilities. Some aircraft inspire an instant rapport; the Kid did exactly that. Being familiar with his big brother may have been one reason, but despite the fact that he only had 1h flying in his logbook, I felt completely confident with the Kid. I checked out the rate of climb, and came up with around 300ft/min – pretty much in line with what you’d expect. A rough check of indicated airspeed against GPS indicated that it was around 10mph optimistic, so the comfortable cruise speed of 60mph indicated, at 5500rpm, was more like 50mph true. The maximum level speed was around 70mph indicated. But don’t pay too much attention to these figures; the little F33 engine was Terry’s choice in order to be sure he’d come within the weight limit, and it was turning a two-blade Powerfin propeller. By the following week, it was being tested with a three-blade Ecoprop which was said to give improved performance. Because it’s deregulated, you can fit what you like within the w April 2009 23 flight test TECHNICAL DATA Kid Escapade MANUFACTURER Escapade Aircraft Ltd., Hangar 3, Old Sarum Airfield, Salisbury, Wiltshire, SP4 6DZ tel 01722 770039; [email protected]; www.escapadeaircraft.com. Proprietor: Terry Francis. SUMMARY 2 1 3 w definition. How about the flat twin two-stroke Hirth F23, which 4 5 6 This page: (1) brakes are optional, but handy to have; (2) Hirth F33AS engine belt and reduction drive; (3) view from the driving seat; (4) sharp dip in the rear cabin profile accommodates folded wings; (5) comfortable but non-adjustable seat; and (6) more room in here than you might imagine Facing page: Escapade owner Terry Francis with pride and joy 24 Microlight Flying gets you 50hp? Or maybe the Solo four-stroke twin? The world’s your lobster. The stall was as benign as you’d expect with the very low wing loading – generally a stable mush which could be encouraged into a straight-through stall break with mild acceleration, much the same as the Escapade. And there was a family resemblance in turns too – both require the use of your feet to overcome the adverse yaw. The trim is reasonably effective, though I don’t think the trim range had been matched to the lightweight engine up front. Personally, I’m not sure whether a trim is required at all – the forces are so light, I’d be tempted to save the weight and fit a permanent trim for a reasonable cruise condition. Similarly with the yaw stability; if you put it into a sideslip and take your feet off the rudder pedals, it only recovers slowly. But this is deregulated flying. If you want to fit springs or a larger fin, you can do so. You’ll learn loads about flying in the process, and at minimum risk. One of the things I like about the Escapade is the excellent view in turns and I was pleased to find the Kid was also pretty good in this respect; despite the narrower roof, one could see the horizon in a turn in a standard 30° bank. And the opening windows made it into a really good camera platform too – easier if you take them off beforehand, but still perfectly possible to open in flight for optimum clarity. I’d felt immediately at home with the Kid, and didn’t want to return. I tooled around the sky as long as I reasonably could before heading reluctantly back to the busy Old Sarum circuit to land, and here, as with all other phases of flight, the Kid was a joy. I set up a reasonably sensible speed on the approach, flared as normal, and we settled gently back on the grass, with nary a bounce, and well before the 50m marker came up. I taxied back and let the engine settle at idle before shutting down. The lack of a castoring tailwheel meant one couldn’t do the fancy trick of spinning it on one wheel to park it, but the light weight makes ground handling so very much simpler than with a two-seater. Otherwise it wasn’t a problem, and Shadow Flight Centre’s Ray Proost, who’s done the majority of the flying to date, reckons he’s handled it satisfactorily in 15mph crosswinds, both on the ground and in the air. Putting it away, we got to demonstrate the Kid’s party trick: the wing fold. Remove the two pins at the root of the leading edges and the wings fold back neatly against the fin, ready to slip into the smallest available space in the hangar, or – better still – onto a trailer to go in your garage or back garden. It’s even faster than the Escapade, since you don’t have a turtle deck to remove. It takes less than a couple of minutes, and I can vouch for the Escapade’s durability on an open trailer, having towed it many hundreds of miles without a problem. The Kid would be as good, with a suitable lightweight trailer. Simpler times If you haven’t tried this kind of low-energy flying before, may I suggest you give it a whirl? A 450kg, 160mph microlight is all about getting from A to B as fast as possible, and needs pretty intense concentration at all phases of flight – and particularly if it all goes quiet up front. Sure, 50mph and 105kg won’t get you anywhere very fast, but is that really the point? Private aviation can never really compare with ground transport for convenience, speed and cost, and with the Kid you can sit back and enjoy the view from 1000ft, secure in the knowledge that if there’s a problem up front you can put it down safely pretty much anywhere. Most microlighters are tinkerers at heart, and want to personalize their machine to a greater or lesser extent. Here’s your opportunity. It’s a well tried and tested layout, which should allow a modicum of tinkering without any significant risk. And because there’s no need to be an approved manufacturer, Terry will supply you the materials in whatever state you fancy – from bare metal airframe at £6000, to a completed airframe with your choice of engine, propeller and airframe, which will cost around £18,000, depending on which engine you choose. And while the first few airframes are of American manufacture, Terry’s planning to make subsequent examples locally. The Kid would be an ideal vehicle for the USSR rally, with plenty of space in the back for a tent and some spare two-stroke oil. The orders are starting to arrive on Terry’s desk, so you’d better get in touch quickly if you want yours to be ready by then! Single-seat high wing monoplane with conventional three-axis control. Wings have unswept leading edges, unswept trailing edges and constant chord; conventional tail. Pitch control by elevator on tail; yaw control by finmounted rudder; roll control by ailerons. Wing braced by struts from below; wing profile N/A ; 100% double-surface. Undercarriage has three wheels in taildragger formation; bungee suspension, on mainwheels. Push-right go-right tailwheel steering connected to aerodynamic controls. Hydraulic disc brakes on mainwheels. Fabric-covered welded steel-tube fuselage and tail surfaces; aluminiumtube wing spars with ply ribs, fabric-covered. Engine mounted below wing, driving tractor propeller. EXTERNAL DIMENSIONS & AREAS Length overall 4.92m. Height overall NA. Wing span 8.94m. Constant chord 1.17m. Dihedral 1.0°. Sweepback 0°. Main wing area 10.5m². Aileron area 1.02m² . Aspect ratio 7.64/1. Fin area 0.31m². Rudder area 0.45m². Elevator area 0.63m². Tailplane area 0.87 m². Wheel track 1.43m. Wheelbase 3.73m. Main wheels dia 34cm. Tailwheel dia 10cm. POWER PLANT Hirth F33AS engine, air-cooled. Max power 28hp at 6200rpm. Powerfin two-blade propeller, 1.32m dia, ground-adjustable pitch. Belt-drive reduction, ratio 1.25/1. Max static thrust N/A. Power per unit area 2.67hp/m². Fuel capacity 20 litre. WEIGHTS & LOADINGS Empty weight 102.5kg. Max take-off weight 235kg. Payload 133.5kg. Max wing loading 22.38kg/m². Max power loading 8.39kg/hp. Load factors +4, -2 recommended, +6, -3 ultimate. PERFORMANCE* Max level speed 60mph. Never exceed speed 101mph. Economic cruising speed 50mph. Stall speed 25mph. Max climb rate at sea level 300ft/min. Min sink rate 300ft/min at 35mph. Best glide ratio with power off N/A at 40mph. Takeoff distance to clear 15m obstacle 50m on grass. Landing distance to clear 15m obstacle 50m on grass. Service ceiling N/A. Range at average cruising speed N/A miles. Noise level N/A dB(A) LEL. * Under unspecified test conditions PRICE INCLUDING VAT £13,000 as tested (rapid-build kit with specification as above), £18,000 ready to fly. N/A = Not available Figures above are manufacturer’s/importer’s data Figures in text are tester’s experience April 2009 25