Instrument Ground School Hazardous Weather

1. Instrument Ground School Hazardous Weather Authored By Lt Colonel Garrett L. Sager 30-Jan-2006 TX-129th Fort Worth Senior SquadronModified by Lt Colonel Fred BlundellTX-129 Fort Worth Senior Squadron For Local Training Rev 5.0 02-Jan-2014

2. This Training Slide Show is a project undertaken by Lt Colonel Fred Blundell of the TX-129 Fort Worth Senior Squadron, Fort Worth, TX for local use to assist those CAP Members interested in advancing their skills. The information contained herein is for CAP Member’s personal use and is not intended to replace or be a substitute for any of the CAP National Training Programs. Users should review the presentation’s Revision Number at the end of each file name to ensure that they have the most current publication.

3. Instrument Ground School Hazardous Weather • Weather Hazards to Flight • “Most Weather is Flyable” – Robert Buck • There a primarily 3 Weather Hazards can really get you into trouble: • Low Visibility / Ceilings • Thunderstorms • Ice

4. Instrument Ground School Hazardous Weather • The #1 Rule to Dealing with Hazardous Weather is: Always have a way out! • That means knowing the weather around, above & below. • Know Yourself, and resist influence of outside factors • Passengers • “Get-there-itis”

5. Instrument Ground School Hazardous Weather • Low Visibility • Hazards • Mountain Obscuration • Inability to Identify Runway Environment • Caused By • Fog • Stable Air with Low Clouds • Rain

6. Instrument Ground School Hazardous Weather • Fog • Coastal areas • Large bodies of water, rivers • Upslope Fog • Valleys • Precipitation Induced

7. Instrument Ground School Hazardous Weather • Low Visibility requires Precision! • Maintain Altitude, Heading, Navigation Track precisely! • Follow Instrument Procedures precisely • Departure • Enroute • Arrival • Approach

8. Instrument Ground School Hazardous Weather • Low Visibility on Departure: • Takeoff Minimums and Obstacle Departure Procedures • SID’s

9. Instrument Ground School Hazardous Weather • Low Visibility Enroute & Arrival • Know MEA, MOCA, MRA, etc. • STARS • Follow airways precisely, especially in mountain areas

10. Instrument Ground School Hazardous Weather • Low Visibility on Approach: • Don’t be committed to landing at an airport that’s below minimums • Have a good alternate, with plenty of fuel to get there. • Alternate Minimums • Never duck below minimums!

11. Instrument Ground School Hazardous Weather • Low Visibility • Set Personal Minimums • Know weather trends, and have personal pre-departure destination minimums. • At the destination, set personal minimums for approach

12. Instrument Ground School Hazardous Weather • Low Visibility • Know where VFR weather is • Especially handy during emergencies, like electrical / radio failure where IFR navigation capability is severely limited. • Have backup navigation & communication ability – handheld Nav/Com & GPS.

13. Instrument Ground School Hazardous Weather • Low Visibility – Resources • AOPA ASF Online Course – Weather Wise: Ceiling & Visibility • Aviation Weather, Chap. 12.

14. Instrument Ground School Hazardous Weather • Thunderstorms • Hazards • Severe or Extreme Turbulence • Hail • Lightning • Causes & Types • Airmass • Frontal

15. Instrument Ground School Hazardous Weather • Thunderstorms • Produced by cumulonimbus clouds, and occur with • Water Vapor • Unstable Lapse Rate • Lifting Action

16. Instrument Ground School Hazardous Weather • Thunderstorms Life Cycle • Cumulus – the building stage. • Towering Cumulus, with continuous updrafts • Mature • Greatest Intensity, both updrafts & downdrafts • Dissipating • Continuous downdrafts, raining out.

17. Instrument Ground School Hazardous Weather • Thunderstorms

18. Instrument Ground School Hazardous Weather • Thunderstorms • Lapse rate > 2C per 1000 ft, combined with high humidity indicates an unstable atmosphere, and thunderstorms are likely. • Moist air is less stable than dry air, because it cools more slowly with altitude, so it must rise higher to cool.

19. Instrument Ground School Hazardous Weather • Thunderstorms • K-Index measures moisture content of the atmosphere • High K-Index means Moist Air • Low K-Index means Dry Air

20. Instrument Ground School Hazardous Weather • Thunderstorms • Use Lifted Index to measure atmospheric stability, i.e.. thunderstorm potential.

21. Instrument Ground School Hazardous Weather • Thunderstorms

22. Instrument Ground School Hazardous Weather • Thunderstorms • Avoid ALL Thunderstorms, and especially Strong Thunderstorms by 20 nm or more • May cause turbulence and hail miles from the storm. • Remember that even a benign looking cell can become a monster in minutes. • Do Not Fly Under Thunderstorms, either. • Fly well clear of area, or land and wait for the storm to pass.

23. Instrument Ground School Hazardous Weather • Thunderstorms • Embedded thunderstorms are storms that are obscured by cloudy conditions, haze layers, etc. • Visual “see & avoid” may be inadequate • “Spherics”, like Stormscope or Strikefinder, detect electrical discharge of lightning strikes • Use Spherics to stay well clear of thunderstorm areas • Do NOT Use to pick your way between cells

24. Instrument Ground School Hazardous Weather • Thunderstorms • Radar detects precipitation, not instrument conditions. • Learn to use and interpret radar properly • Without Radar or Spherics, avoid IMC around thunderstorms.

25. Instrument Ground School Hazardous Weather • Thunderstorm Penetration • You’ve run out of options, got yourself boxed into a corner, and penetration is inevitable. • You’ve probably passed up numerous opportunities to land, or go around, but kept saying, “this doesn’t look so bad”, and now you’re stuck. • Penetrate fronts or squall lines where the tops are the lowest • Do NOT fly through areas of fuzzy white – that’s probably hail • Dark clouds mean rain

26. Instrument Ground School Hazardous Weather • Thunderstorm Penetration • Fly straight ahead, Do not turn around • Turn increases load factor on airplane • Straight through is often the shortest route out of the storm. • Maintain Attitude – Wings Level, Level Pitch • Do not try to maintain altitude • Autopilot Altitude-Hold Off

27. Instrument Ground School Hazardous Weather • Thunderstorm Penetration • Set power & trim for turbulence penetration speed • Pitot & Carb Heat ON • Tighten Seatbelts • Panel lights to maximum, seat at lowest setting, and focus on the instruments • Lightning flashes may cause temporary blindness

28. Instrument Ground School Hazardous Weather • Thunderstorm Penetration • You will probably be more scared than you’ve ever been – Control Your Fear. • It’s loud, turbulent, and very distracting • Never Stop Flying the Airplane • Maintain attitude and airspeed • Most T-storm related in-flight breakups result from loss of control, and overspeed.

29. Instrument Ground School Hazardous Weather • Thunderstorms Resources • Aviation Weather, Chap. 11 • “Weather Flying” Chap. 14, Robert Buck • “Severe Weather Flying”, Dennis Newton • Weather Subject Area @ www.thecfi.com • AOPA ASF Subject Reports

30. Instrument Ground School Hazardous Weather • Icing

31. Instrument Ground School Hazardous Weather • Icing – Effects • Clear Ice & Rime Ice

32. Instrument Ground School Hazardous Weather • Icing – Effects • Frost on the wings disrupts the flow over the wings, and should be removed before flight. • Tests indicate that frost, snow or ice with texture similar to coarse sandpaper reduces lift by up to 30%, and increased drag by up to 40%.

33. Instrument Ground School Hazardous Weather • Icing - Effects • Ice collects on any protuberance, especially those with sharp leading edges. • Wings & Stabilizers • Causes a loss of lift, increased drag • Antennas • Ice may cause to flutter, and break

34. Instrument Ground School Hazardous Weather • Icing • Ice collects on any protuberance, especially those with sharp leading edges. • Pitot Tubes • Ice obstructs pitot-tube, causing loss of airspeed indication • Engine Inlets • Obstructs induction system • Propellers • Unbalances propeller, causing severe vibrations • Causes loss of lift, and therefore loss of thrust.

35. Instrument Ground School Hazardous Weather • Icing - Tail Stall • Due to smaller leading edge, tail collects ice faster than wing. • Loss of tail down force causes nose-down pitch. • Flaps change the airflow over the tail.

36. Instrument Ground School Hazardous Weather

37. Instrument Ground School Hazardous Weather • Icing • Requires 2 conditions • Visible Moisture • Temperature at or below freezing • “Freezing Level” is the altitude where freezing temperatures exist. • Can be determined using the average lapse rate of 2C per 1000 ft. • Not a precise indication, so leave some margin.

38. Instrument Ground School Hazardous Weather • Icing • Freezing rain results in the fastest and greatest accumulation of ice. • Indicates warmer temperatures above – temperature inversion. • Super-Cooled Liquid Droplets (SLD) are liquid below freezing, large diameter, and freeze on impact.

39. Instrument Ground School Hazardous Weather • Icing

40. Instrument Ground School Hazardous Weather • Icing • Freezing drizzle results in an accumulation of ice similar to freezing rain. • May form due to “collision-coalescence”, and doesn’t necessarily indicate warmer temperatures above.

41. Instrument Ground School Hazardous Weather • Icing • Ice pellets caused by rain freezing at higher altitude • Heavy, wet snow means temperature is above freezing at your altitude. • It formed above you, but is on the verge of melting

42. Instrument Ground School Hazardous Weather • Icing • In stratus clouds, 90% of ice occurs within 3000 feet altitude band. • In cumulus clouds, icing can occur over any altitude range • Avoid individual clouds when conditions are right for ice.

43. Instrument Ground School Hazardous Weather

44. Instrument Ground School Hazardous Weather • Icing – The Appleman Line (IFR Magazine, Feb.06) • Icing is most likely when temperatures are between 0C & -22C • 87% of reported icing (with >50% humidity outside cloud) • 71% of reported icing occurs with >65% humidity, and temperatures between -2C & -15C.

45. Instrument Ground School Hazardous Weather • Icing – The Appleman Line (IFR Magazine, Feb.06) • 95% Probability of Icing occurs under the following conditions: • OAT < 0C, and • OAT is between dewpoint (T = Td) and 80% dewpoint (T = 0.8*Td)

46. Instrument Ground School Hazardous Weather • Icing

47. Instrument Ground School Hazardous Weather • Icing

48. Instrument Ground School Hazardous Weather • Icing Strategies • In stratus clouds, with no freezing rain, Climb • In cumulus clouds, stay in clear air • Approaching a warm front from behind • Climb along the front, the descend rapidly through it. • Turn Around

49. Instrument Ground School Hazardous Weather • Icing Case Study • Field elevation around 600 feet, • Temp = 48F, DP = 37F • At what altitude would the cloud bases be, and would you expect to encounter ice in the clouds • If encountering ice, what would you do about it?

50. Instrument Ground School Hazardous Weather • Icing Case Study • Cirrus SR22, N87HK, departed Birmingham AL on 13 Jan 06 at 1601 CST headed for Orlando, ATP rated pilot. • DUATS briefing • Forecast ice from 8000 to 10,000 feet. • Pilot overlooked Airmet for ice from 3000 to 8000 feet. • Pilot climbs at 120 kias, enters clouds at 5000 feet, encounters ice at 7000 feet. • Stated he did not know MOCA where he was.