Canadian Advanced Soaring Finding and centering thermals

THERMALLING (and how to avoid landing out) Other possible titles: “How I landed out over 50 times.” “50 Farming families I’ve met.” “ S.W. Ontario walking tours.”

Purpose Improve your soaring skills. By learning from the mistakes of others. Reach the point where you enjoy cross country soaring. Give you some insights into current thinking about cross country. Pass along your new skills and insights to fellow pilots.

KEY MESSAGES Safety, safety, safety! Don’t just talk about it – strive to be a shining example of a good pilot. Club policy on out landings versus straight in approaches. Train on weak days. Turn tightly – wimpy 27 degree turns guarantee failure. Read the sky. Know your instruments

A WORD OF CAUTION When we talk about actual thermal strength, we should be talking about ACHIEVED climb rate and not indicated climb rate. A 4 knot (indicated) thermal will translate into an achieved climb of 2 knots if you are a superior pilot.

What does a thermal look like? A tree – long trunk with bushy top? A column of warm air? Multiple cells (cores) feeding a large Cu? Impact of wind shear?

Which thermal model? Whatever works for you. No theory will ever beat practical experience.

HOW TO READ CLOUDS Depth of cloud – vertical development. Shape, Texture, Curl over. Solid, dark base. Firm profile – not fuzzy. Cloud shadow. (Overdevelopment?) Growing clouds, Mature clouds and dissipating clouds. Learn to recognize the differences! Beware of towering Cu.

How to Read Clouds Rule of thumb – 1 in 3 clouds working. Thermal height is proportional to distance between thermals. 8,000’ cloud base – thermals far apart, lots of sink. 3,000’ cloud base – thermals close together, not much sink. Thermal cycles - try to get in phase with growing clouds.

HOW ABOUT CLOUD STREETS? Multiple cores roughly aligned with the wind. Start low and run hard when high. When high – use cloud shadows. Think about this: If there are cloud streets operating then there must be sink streets!!!

Note cloud shadow!

SINK STREETS Trust me – they exist! Turn 90 degrees and get out of Dodge. Remember – you can get streets of lift and sink on Blue days.

Thermalling Rules First glider in thermal establishes direction of turn. When joining a thermal do NOT interfere with other gliders. Keep yourself visible to other pilots in the thermal. If you are climbing faster than other gliders – you must not impede other pilots Maintain a good lookout at all times.

THERMALLING RULES Do not reverse your turn in a thermal – another glider could be on your tail. Suggestion – give way to less experienced students/pilots. Suggestion # 2 - in competitive flying – do not impede the climb of a better pilot. Your generosity will be rewarded!!!!

FINDING THERMALS??

Thermal Indicators WHEN HIGH ….. Use clouds or haze domes. WHEN LOW….. Use terrain features. On overcast (overdeveloped) days fly to areas of sunshine.

GROUND FEATURES GROUND FEATURES Slopes/hills Sand pits/quarries – Ingersoll! Dark fields Villages/towns Mfg. Plants/car parks Fires Forests? Lakes?

Thermal Indicators Other gliders – most times. Birds – hawks and seagulls. Dust “devils” – ploughed fields. Debris – plastic bags, hay, small cars. Slopes, ridges, hills, towns, factories etc. Fires – often quite small but powerful. Remember the rule ……

READING THE SKY Overcast days (overdevelopment or spread out) Fly from sunlit area to new sunlit spot. Cirrus rapidly approaching? Don’t give up – slow down and seek ground sources of lift. Look for other gliders. Spread out if you are gaggle flying.

THERMALING SKILLS Constant airspeed – fly attitude! Constant angle of bank! Tight turns – our comfort zone is a mere 27 degrees – pilots consistently over estimate the actual angle of bank. We need to turn at 45 degree angle of bank. How about stalling?

Calculate my bank angle? Airspeed – you know. # seconds to complete 360° turn – you know. Gives you approximate angle of bank. Virtually all new pilots overestimate their bank angle.

Circling Time in Thermals Bank angle 30°35°40°45° 40 knots 45 knots 23 sec. 26 sec. 19 sec. 21 sec. 16 sec. 18 sec. 13 sec. 15 sec. 50 knots 55 knots 29 sec. 31 sec. 24 sec. 26 sec. 20 sec. 22 sec. 16 sec. 18 sec.

Circling Time in thermals Better pilots typically fly at 45 to – 23 seconds per turn. If you are wandering around at 20 degree angle of bank – you cannot thermal efficiently. Good training – 42 knots – around 19 to 20 seconds. Caution – remember laminar flow … you can also thermal too slowly.

While you are thermalling….. Read the sky ahead. Pick out growing cloud(s) – have more than one option! Avoid blue holes! Select best course line based on cloud layout. If you deviate – try to deviate upwind.

Common Thermalling Errors Look outside – keep your head out of the cockpit! Use the audio function. Use ALL your senses. Speed control – fly attitude – fear of stalling? Angle of bank – fear of stalling? How do I calculate my bank angle?

Common Thermalling Errors Taking every thermal. Thermal “love in” – the last to leave? Follow the mob or lead? Team flying – single file or spread out? On blue days it is essential that all gliders on a task spread out.

Common Thermalling Errors Turning too soon when you enter a thermal. Banking at high speed : 60 knots + +. Chasing the vario – remember vario lag. Ignoring the yaw string. Rough control movements once established in the thermal. Entering thermals at high speed. Leaving thermals at high speed.

KEY POINT IT TAKES TIME TO CENTER THERMALS! A “good” pilot will take FOUR turns to core a thermal. That is 70+ seconds, over a minute – a long, long time, going nowhere! A really superior pilot will center the thermal in two turns. Time saved during a 20 thermal flight? At least 10 minutes!! An “average” pilot may NEVER center the thermal.

KEY POINTS Read clouds carefully. Enter and leave thermals correctly. Turn tightly. Be selective with thermals you take. Use conservative MacCready settings. Speed up by slowing down between thermals. Be flexible!

MOST IMPORTANT POINT OF ALL! STOP WAITING FOR THE PERFECT DAY ! Train when the weather is weak.

Cruising between Thermals This should be a very busy time for you. How fast to fly? How slowly? Go left? Go right? Fly through the blue hole or go around it? Avoid the overcast ahead on course line? Catch up with that LS 8 ?

Between Thermals Lake effect. Turn point in blue air – what to do? First – decide how far you have to fly in blue air. Second – climb as high as possible. Slow down and be patient. Work weak lift in blue air – particularly after turn point- wind at your back.

Psychological Factors The importance of flexibility - learn to adjust your pace. At 7,000 feet ignore weak lift. At 2,000 feet take anything! High = Fast Low = Slow Be patient – a 1.5 knot thermal at 1,200 feet may be a 4 knot thermal at 3,000 feet

Psychological Factors Psychological Factors The need for companionship – follow the leader often puts your brain in neutral. Think for yourself – avoid the herd mentality. The other guy is just a dumb as you are. (Most of the time, anyway!)

The Tortoise and the Hare The Hare: 20% fewer thermals. Average thermal taken 30% better Yet the Tortoise won! Why??? The Hare needs to work on cruising between thermals.

PLANNING Check lists. Weather forecast? Declaration. Water*, Food. Pee system. Map preparation – do not rely on GPS. Course line? Key radio frequencies. * Top priority for safety! Know how to operate your instruments – vario, computer, radio etc. Can you reach everything? Weather shaping up per forecast? Take your time – let the day develop. Get input from qualified pilots. Be positive – don’t get psyched out!

PERSONAL AWARENESS Fitness – both physical and mental. Hydration – very important!!! Food - nourish the body. Relaxed awareness while flying. Look. Listen. Feel.

Summary Develop thermalling skills – particularly on weak days. Constant angle of bank, constant airspeed. Tight turns ! CONSERVATIVE ring setting. Make haste slowly and steadily. Read the sky ahead. Avoid blue holes. Work on long inter thermal glides – 15 to 20km. Lead – don’t follow. Have fun!

Airport Hopping (Airport hoping?) Seductive for the low time pilot. Pros and cons. Silver distance – o.k. Dangerous for longer flights? Your energy and concentration is on the next airport and NOT on weather reading. Actually slows your speed dramatically. Many airstrips are very narrow! Target fixation – final glides…. The mind stops working!

Recommended Reading List A comprehensive reading list will be ed along with a copy of this presentation. address:

Recommended reading list Soaring Cross CountryReichmann New Soaring PilotWelch & Irving Winning 11Moffat The Platypus PapersBird Meteorology for glider pilotsWallington Transition to glidersKnauff

QUESTIONS? Thank you for supporting our National Team! Enjoy a terrific soaring season and set your sights high. Fly safely and with joy!