THERMALLING (and how to avoid landing out)

2. 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.”

3. 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.

4. The Need for Speed • All cross country flights are a race against time. • Essential to understand the importance of a superior climb rate as compared to high inter- thermal speed. (Any fool can fly fast!) • Thermal activity – weak in morning and late afternoon – requires tactical adjustments. • Late in the day – STAY HIGH!

5. First Cross Country • The 50 km. task is easy – in a modern glider – assuming decent weather conditions.. • 6,000 feet msl. at SOSA – York Soaring is in the bag. • The biggest barrier you face is the psychological fear of cutting the apron strings.

6. YOUR OBJECTIVE • Badge flying is NOT a competition. • Your purpose is to COMPLETE THE TASK. • Who cares if you complete a 300km. flight in 4 hours or 6 hours? • You should ! Higher speed requires mental discipline and courage. • Yet, enjoy the experience – the journey is just as important as the achievement.

7. The Big One – 300km. • Junior glide ratio is 34:1 at fairly high airspeed. • Most modern fiberglass gliders are in the 33:1 to 37:1 range. Astir, Libelle, Junior, Std. Cirrus. • “Even” a 1-23, 1-34 or a 1-35 are capable of 300 km. + + • The key – good thermalling skills and adequate planning. • Conclusion – 300 km. flight is possible on many “average” soaring days in S.W. Ont.

8. 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! PLANNING

9. The Big Day • Once airborne, get a feeling for the day. • How do actual conditions compare to the forecast? • Thermal strength and ease of connecting. • Wind shear – at what height? • Operating band*– thermals consistent above 2,500 feet or higher? • Resist the pressure to start too early! *Note – operating band will change as the day develops.

10. 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 ……

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

12. 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?

13. Calculate my bank angle? • Airspeed – you know. • # seconds to complete 360° turn – you know. • Gives you approximate angle of bank.

14. Circling Time in Thermals

15. Circling Time in thermals • Better pilots typically fly at 45 to 55 knots @ 19 – 23 seconds per turn. • If you are wandering around at 20 degree angle of bank – you cannot thermal efficiently. • Good training – Blanik @ 42 knots – around 19 to 20 seconds. • Caution – remember laminar flow … you can also thermal too slowly.

16. 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.

17. 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.

18. “Average” thermal strength • Typical flight computer – average thermal strength based on: • Start of climb? • Last 10 seconds? • Last 20 seconds? • Last minute? • Duration of flight? • Computers have given us greater insight into achieved speeds.

19. Average thermal strength • Typically based on the past 20 to 30 seconds. • That is why a 4 knot day really turns out to be a 1.7 to 2.0 knot day when you analyze the data. • Beware of optimistic radio calls – “5 knots here.”

20. Thermal strength* in knots*(Assuming 4 turns to center)

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

22. Cruising between thermals • How FAST should I fly? • If I fly too fast, what happens? • If I fly too slowly, what happens? • The good old days of “pure” MacCreadyring settings.

23. Impact of Conservative Ring Setting

24. Impact of Conservative Ring settings • If you set the MacCready ring at “0” • How much performance/time do you lose? • Answer – 20%........ Leading to a high probability of an out-landing! • Why? • Reduces your thermal search area. • Limited amount of thermal activity during the day – you run out of time.

25. Thermal Probability S.W. Ontario* 1 mile5 miles10 miles 1 knot 20 9099 2 knot10 6184 4 knot5 3052 6 knot 21018 * Standard class glider.

26. KEY LESSON • IT TAKES TIME TO CENTER THERMALS! • A “good” pilot will take FOUR turns to core a thermal. That is 120 seconds, 2 minutes – a long, long time, going nowhere! • A really superior pilot will center the thermal in two turns. Time saved during a 20 thermal flight? • 10 minutes!! • An “average” pilot may NEVER center the thermal.

27. 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.

28. 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.

29. 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.

30. Between Thermals • Blue holes - course line deviations. How far ? Remember your objective! • Upwind or downwind? • Cloud shadow. • Overdevelopment – how to handle? • Cloud streets – visible and not so visible. • Sink streets – be decisive – act quickly. • Blue days – sunglasses.

31. 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.

32. Course deviations • Remember your mission ! • A 30° course deviation causes you to fly 15% further. • At 80 knots, 3 miles and 30° deviation costs you 20 seconds. • If you gain a mere 100 feet, you are better off than the blue hole puncher.

33. Course Deviations(The Tortoise and the Hare) • High personal confidence in my thermalling ability. • Shortest distance (best speed) between two points? Straight line ? • Flying with others showed that the most effective way to fly between two points is frequently made by deviating under “wimpy” lift.

34. Effective Inter-thermal Flying • Fly with purpose! Don’t let the thermals push you around

35. Effective Inter-thermal Flying • When you feel lift always slow down and turn into it • Anytime you can climb while flying straight on course is advantageous

36. Turn point Tactics • Take upwind turn point……….. LOW.* • Take downwind turn point…… HIGH. *( Within reason, of course!) • Bartell – “ a 2 knot thermal going downwind is as good as an 8 knot thermal going upwind.”

37. 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!

38. 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.

39. 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

40. Psychological Factors • Develop stamina – both physical and mental. • Fight the urge to “do something”. Be patient! • Avoid follow the leader – fly your own flight. • Fight the urge to “catch up” – the need for companionship. • Remember your objective – finish the task safely.

41. 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!)

42. Psychological Factors • Don’t get sucked in by higher performance gliders. • Be realistic about your gliders performance: Astir versus Ventus Hornet versus LS 6 LS 6 versus Nimbus 3 • McMaster strategy – optimize your gliders performance envelope.

43. 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!

44. PRACTICAL STEPS • The importance of weak days. • Use 1 knot thermals around the field. • Work on low saves around your Club. (Just brief the Duty Instructor!) Work on stamina. • Release early. The Tow pilot creed – “if he fails to release in lift, he must want sink”.

45. 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!

46. Recommended reading list • Soaring Cross Country Reichmann • New Soaring Pilot Welch & Irving • Winning 11 Moffat • The Platypus Papers Bird • Meteorology for glider pilots Wallington • Transition to gliders Knauff

47. Recommended Reading List • A comprehensive reading list will be e-mailed along with a copy of this presentation. E-mail address: John_brennan@sympatico.ca