| A week later than originally scheduled Bumpy Green headed back to Vauxhall Model Flying Club for a rather special test flight of a rather special model. Beginning with a round up of camera batteries and media on the Saturday night and ending on a very cold but bright Sunday morning (including a 10 minute car defrosting session) we set off early for the club in anticipation of the event we were going to see.
John Greenfield of Ghost Squadron was test flying his latest creation, an Air World 3rd scale Swift aerobatic glider belonging to Stuart Mackay. 5.2m span and weighing in at a 43lb unballasted, with ballast loaded it will approach 60lb. The model requires 11 servos to operate with four high powered digital JR units for the ailerons, three heavy duty servos on the rudder and elevators with 20 KG pull each, embedded servos for the two wing mounted airbrakes, one for the retracting undercarriage (which is a fully sprung and gas damped unit), one for the proportional wheel brakes and one for the aero tow release. This is a German kit imported by
Stuart Mackay Models of Suffolk.
The Swift was to be towed up by a 44% Giles flown by Steve Holland. Powered by Desert Aircraft 150 engine, which is a 150cc or 9.15 cu in petrol (spark ignition) unit, outputs 16.5 hp and weighs 7.9 lb (3.6). It is capable of swinging 30" plus props and hauls the Giles, weighing 36lb all up, around the sky with considerable ease. The model was bought second hand and has led an interesting life at the hands of Mr Holland. Used mainly as a 'spare' model it was have a dusting off session for this years season after a short break from flying.
Both models assembled and ready to fly, a long length of day-glow orange nylon cord was used as a tow rope.
Up and away into the clear blue sky, the Giles had more than enough power to pull the Swift to a great height, prompting John to mention the club has a flying altitude limit. After the fourth successful tow and release both pilots were performing rolls during the ascent, sometimes in opposite directions, quite a sight.
A very graceful model to see flying, it seems almost effortless as it glides from one side of the site to the other with very little height lost on a flat glide. On a fast fly-by the model whistles and shrieks as the air passes over the various control surfaces.
Also capable of long flowing aerobatic manoeuvres which, as you can see from the first picture here throw the pilot around inside the cockpit without mercy. It was commented that maybe John should invest in a nice seat and harness for the poor chap inside.
Airbrakes up for a slow approach and a gentle flair at the end gets the model onto the landing strip with minimal fuss. A combination of air brakes and wheel brakes get this large model onto the ground and stopped in a very short space, less than some models half it's size.
Back safely again after a good number of flights and John fetches the model looking very pleased with the results ~ and rightly so. A superbly built model, flown equally superbly
For a warm up Steve did a quick fly about with a rather sporty electric powered Mini Majestic. Flying on 14 cells and an LRK 350-25 brushless outrunner motor. A nice quiet start to the days flying, proving a highly aerobatic model aircraft need not be noisy.
As for the Giles, Mr Holland was not just standing around while the glider did it's stuff and treated everyone present to a short aerobatic sequence. Steve is one of the foremost show display pilots in the country and can be seen at many of the UK and Europe's top events.
Photographing such a large model is always a pleasure and being a club field one can get much closer than during a show ~ even with a flight line pass. Great colour scheme on the Giles both above and below.
In for a long slow glide to land, still trailing the dayglow orange tow line (not visible at this resolution sorry). Keep your hands clear of that propeller, it resembles a 30 inch double ended carbon sword. I've heard of people losing fingers on smaller models, this one would take most of your arm off.
Other club member were soon getting aircraft ready as John and Steve returned to the pit area for refueling and adjustments.
One model I look forward to seeing more of in the future is the Trim Aircraft F-86 Sabre of Giuseppe Cannella. Powered by a Japanese Sophia 850 turbine engine delivering 19lb of thrust at 135,000 RPM. On a model weighing 16lb dry it should fly superbly. Fuel used is paraffin with 20% petrol which allows the engine to self ignite. The engine also features a separate oil feed system so pre mixing is not required.
The model is still in bare skin so to speak with the fibre glass fuselage, foam glass/veneered wings and glassed balsa tail fins uncovered or painted. The model features an all moving tail and on 2 litres of fuel will be capable of 6 minute flights. The other model is a Savex Aero L39 Albatross with Wren turbine power which had not flown by the time we left the flying field to find some lunch.
A couple of fast ground runs across the strip were all that was planned for the day to test the engine response. We had wondered if it would actually get to the short hop stage as the turbine whistled up to speed and the Sabre fairly shot across the grass. That is until an inadvertent wrong switch was flicked (we've all done it) and the nose leg of the alloy spring air retracts disappeared inside. Happy with the ground runs Giuseppe returned to the pit area to find no damage had been caused by the untimely undercarriage retraction.
Another lively jet, this time being
flown by Paul Gray. The Aero L39 Albatross is from Czech company
Savex and
at a very reasonable £370. Reasonable because it comes pre painted
in a choice of colours, has the retracting undercarriage wells
already in place and employs a composite glass/carbon fibre fuselage.
Powered by a Wren 44 turbine pushing out 8.5lb thrust with the
addition of an improved tailpipe. Idle is a sedate 10,000 rpm and
max thrust is 190,000 rpm and many updates are fitted on this engine
which is an ongoing test bed for Wren modifications. The model
flies very well and uses standard undercarriage legs and wheels,
Futaba mini servos and takes off and lands in less space than most
I.C. powered planes of similar size. Paul is an advocate of simple
turbine modeling and he says it doesn't get much simpler than
the Aero L39 / Wren combination he uses.
The following model is a 'Greenly' a large fairly simple model that is quite aerobatic as well as being very stable in flight.
A large dihedral helps this model fly much like a big trainer.
The Greenly floats back to earth very slowly for a perfect landing.
Another Greenly is Kev's or Kevley as he must be called whilst flying it.
More reminiscent of an ATS Super Sport or WOT4 and highly aerobatic to boot.
With the zero dihedral wing it flies equally well upside down and even on it's side for a tail snaking knife edge.
Landing is no bother at all for Kev with his experience and the amazing stability of the Greenly it is soon touching down for another greaser.
Lastly a couple of dogs. Kim the Collie enjoyed watching the planes but has to be restrained to prevent chase downs. And of course Bumpy Greens very own Mad Dog ~ Kev trying to get his Airmark Cassutt running. (he's the one on the right near the red aeroplane by the way) |
