Oct - Rcsoaring.com

his spotter shouting “fly downwind,” he was convinced and hissmile was almost two metres wide!But the highlight of my day were the flocks of storks. At onepoint there were five separate darkish clouds of the majesticbirds spread across the sky from north to south, storksreturning to Africa across the Bosphorous from northernEurope. Each cloud paused almost stationary in the sky, athousand or more storks thermalling and gaining height beforebreaking away to catch the next batch of lift. How do they allcircle so closely, seemingly in random turmoil, certainly not allin the same direction, without any collision?But whether it’s one stork or a thousand, when they circle itmeans lift! Several of the two-metre models went up to jointhem, and again, even when models were in the thick of theflock and hard to distinguish and keep your eyes on, there wereno collisions.When Philip launched almost into the base of the flock, hecried: “I hope their radar is good,” and amazingly half a minutelater, I saw Philip’s model flying above the flock and to one side.I hope that a reader somewhere will explain this phenomenon.It appears that a well trimmed model glider will climb faster thanthe typical stork in the same thermal. I am confident that Naturehas blessed the stork with super thermal reading skills and finefeatheredaerofoils. If the stork is not climbing as fast as themodel, then either the bird did not want to climb fast in the liftor its wing loading was higher than the model.Whatever the explanation, the storks were a wonderful sight tosee and provided a wonderful bonus to super contest. nThe model is easy to spot as it breaks away from the flock inthis enlarged photo. The storks seem to be just as good atavoiding man-made objects as their own kith and kin!One of what was at one time five flocks of storksthermalling over Istanbul’s two metre class thermalglider contest, and not one collision. See if you canspot either of the two gliders in that lot!52 R/C Soaring Digest