Silent Flight at the Nationals.
Silent Flight classes return to BMFA Buckminster, the National Centre for model flying, at Sewstern NG33 5RW, about 25 mins from Barkston. Visitors are welcome to watch the various Silent Flight competitions which will be taking place over the 3 days of the holiday weekend.
The contests themselves take place on the same 3 days as the Main Nationals and comprise some 5 BMFA, plus 1 BARCS event. These are flown 2 per day, simultaneously, so there should always be something to watch and talk to the competitors about.
“Silent Flight” is a term which covers competitions where, although an electric motor is used to gain height in most categories, the vast majority of the flight is done in gliding mode and is therefore silent. Originally model gliders were towed aloft using a line, very much like a kite, then released to fly as a glider and while “towline glider” as a class still exists, most models are electric launched. Recent improvements in battery and motor technology have resulted in models as large as 4 metres wingspan being launched to 175 metres by a motor/battery/controller package weighing as little as 250gm.
100S Glider. This is a towline glider competition with span restricted to 100 inches and launch by means of a nylon line and an electric winch. After launch the models will try to seek out thermals in an attempt to achieve the maximum required flight time before making a precision landing for extra points. In this and most other classes, the winner gets a score of 1000 points; the remainder proportionally less, this irons out the vagaries of the weather! This competition will finish in the mid afternoon,
2metre Electric Soaring. This day-long competition is for 2m span models flying to a maximum of 175m height using electric power for a maximum of 30seconds, then gliding for a total of 10 minutes before doing a precision landing. The models involved often weigh only 600gr and are used by many people as an introductory type for eSoaring. Many ready-to-fly kits are available for this class. For those who prefer building their own, a considerable number of such alternatives are generally available.
Pic C cap – Extra light construction (glass, pressed on foam) on this 2M eSoarer shows well at sunset
F3K discus-launched glider.
F3K is the International class for hand-launched Radio-Controlled gliders. To get their 1.5 metre models airborne, pilots use a ‘discus launch’, holding the model by the wing tip and rotating rapidly as they launch to 50-60 metres – plenty high enough in the right conditions to find thermal lift to achieve longer flights.
The competition comprises ‘tasks’ where a group of 4-8 pilots will fly head-to-head in the same weather conditions. The tasks are duration based and require precision flying, often with rapid re-launches between the flights to maximise flying time in the ten minute competition ‘slots’.
The best pilots will be able to launch high, fly accurately and smoothly, and think tactically at the same time!
F5J is the newest International class for large electric gliders and require pilots to choose their own launch height then try to complete a 10 minute gliding flight. The launch height is deducted from the time scored and additional landing points, so a minimal height and 10 minute glide is the Holy Grail for a good score but it can make life difficult for thermal detection!
To increase the chances of using even the slightest low level lift, models are becoming lighter and lighter, to the point where some models of 3.5 – 4m span weigh only slightly in excess of 1kg and require ballast to fly in normal British weather!
Instantaneous launch after the starting horn guarantees an interesting spectacle for spectators!
Open eSoaring is an event where models attempt to do a 10 min flight within an 11 minute flight ”window’, after an electric launch to a maximum of 175 metres. A second attempt is allowed within the 11 minute window. Other rules for this class are the same as for the 2m eSoaring class described earlier.
BARCS ELG A rather less-demanding version of the international F5J electric glider class, appealing to club fliers as well as to experts. Big moulded open models of up to 4m span are the most popular but separate classes for (cheaper) 100” and for 2m models are flown at the same time (and have often been known to beat the hi-tech open models). Like F5J, the object is to fly for 10 minutes in a 10 minute slot, with points for precision landing and exciting finishes as everyone who has flown the slot out tries to get down just before the buzzer. Unlike F5J, there is no deduction of points for launching up to 200m and one re-launch is available.
Do please try and visit the Silent Flight Nats to see some of these models in flight!