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Case of the Vanishing Thermal

Date: 01/04/1978
Author: Bob England
Contributor: Tony Williams

Aarh, but we've a lot to learn about these elusive bubbles of hot air. Case in question: Bratten Camp, Friday 17tb. Wind slightly east at times but mostly very good 14 -18 m.p.b. Thermals patchy but often useful, everyone having reasonably comfortable flights and top landings. Occasionally a thermal would bump people up to 5-600 ft. and it was on one particularly good such occasion that Nigel Milnes on a Mariah (my Mariah in fact), and myself on John B's 8 managed to circle over the top towards the car park going rapidly up while our optimism soared to new heights in 1978. At around 850 ft. while sizing up the area behind Bratten and the cloud formations, the lift became less pronounced we had lost it. Although there was still lift around, it seemed the blob bad overtaken us, Nigel scooted back to the ridge then and there, while I persisted a bit longer before deciding 950 ft. and weaker lift were not good enough for a cross country. Case One.

It just so happened that the following day, with light South Westerly forecast - a day of stunning mediocrity at Mere, while driving such stoic flyers as Ray Willis home early at a really Welsh site _ turned out to be exceptionally good at"Merthy Tadpolel'. The Fack twins, Nigel and myself arrived to find the rest of the flyers dormant, "resting between flights", while a Moonraker soared 2-300 ft. in what appeared very bumpy conditions. Not unduly perturbed we commenced rigging. During this process I observed a strong smell. As there was no one particularly unsavoury upwind, and noticing the increase in temperature, I concluded it must be a strong Welsh thermal. Welsh, as the characteristic smell of steel works and the like, being sucked up from the valley below appears an experiencepeculiar to the valleys. The assumed thermal was confirmed by the Moonraker, now 8-900 ft. above the top, and our appetite had been wetted.

As it was late in the day this marked the end of the clearly defined thermals although some good height gains were made until early evening when cloud became thicker. Although it had been the best day's flying so far in this country I was left pondering on what I was doing wrong.

Conclusion: Rather than accept it was my poor flying that lost it for me, I can only conclude that it must be the ridge breaking up the thermal immediately downwind, and had I persisted, I would probably have been rewarded with its reformation, an apparently common occurrence supported by the experience of glider pilots. The moral must be 'Go with it, young man". If you find yourself with the comfortable height to clear any obvious rotor, with any possible forced landing presenting no difficulty then stick with it, for better or worse, the attraction is the frustration of missed opportunities, with the possible addition of an ignominious scrabble for base, and the loss of all that glorious height.

Contributor's Notes:

Bob England was an excellent pilot. He was a member of the UK team on several occasions. He also dabbled in glider design producing the cross-boomless Gannet and contributing to the design of the Hiway Demon. He moved to California in the 1980's. He was killed in a paragliding accident in the 90's at Torrey Pines.


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