Atmospheric Circulation and Air Moisture

• The main driver of atmospheric circulation is the Earth's surface experiencing unequal heating from the sun.
• Every physical weather process involves or results from heat exchange.

Atmospheric Pressure

• Decreases with elevation.
• It decreases 1 inch of mercury per 1,000' elevation gain.
• It decreases -2 degrees Celsius (3.5 degrees Fahrenheit) per 1,000' increase.

Relative Humidity and Dewpoint

• Low clouds and fog are likely when temperature and dewpoint are close.

Air Moisture

• Unsaturated Air: moisture level is below 100% relative humidity.
• Saturated Air: moisture level is below 100% relative humidity.
• Evaporation and Sublimation adds moisture to unsaturated air.
• Evaporation: liquid becomes water vapor.
• Condensation: water vapor becomes liquid water.
• Sublimation: ice becomes water vapor.

Surface Frontal Boundary Line Symbols

• Pressure decreases as a front approaches and increases after it passes.
• Winds turn right after the front goes by.

Thunderstorms

• Stay at least 20 nautical miles away from thunderstorms.
• Three conditions required to form a thunderstorm:
  • Unstable Air: parcels of air are warmer than the nearby environment
  • Lifting Action: front, terrain, and solar heating.
  • High Moisture Levels.
• LIM: Lift, Instability, Moisture.
• Fast-moving cold fronts are usually linked to thunderstorms and squall lines.
• Single Cell: Lasts < 1 hour.
• Multi Cell: Compact cluster of storms in different stages of development.
• Squall Line: Forms 50-100 miles ahead of a fast moving cold front.
• Wind Shear: A change in wind speed and/or direction over a short distance
• Microburst: Is a downdraft associated with connective activity, and is one of the most dangerous sources of wind shear.

Icing

• Pilots are prohibited from flying into KNOWN icing without deicing or anti-icing equipment.

FARs and NTSB Notes

• FAR 61.56 and 61.57
  • Must receive a flight review from an authorized instructor within the preceding 24 calendar months.
  • To carry passengers during the day, in the preceding 90 days, you must complete three takeoffs and three landings in the same category and class of aircraft.
  • To carry passengers at night (1 hour after sunset and 1 hour before sunrise), in the preceding 90 days, you must completed three takeoffs and three landings during night hours and come to a full stop after landing.
  • Category: Airplane. Class: Single Engine Land (SEL)

Definitions of Night - FAR 1.1

• the time between the end of evening civil twilight and the beginning of morning civil twilight.

FAR 91.209

• Position and anti collision lights must be turned on from sunset to sunrise.

FAR 91.17. Drugged Passengers

• a pilot of a civil aircraft cannot allow someone intoxicated or under the influence of drugs to travel in their aircraft, unless it's an emergency

FAR 91.103. Preflight Action

• Each PIC must know all pertinent information about the flight before starting it.

NWKRAFT

• NOTAMS, Weather, Known ATC delays, Runway, Alternates, Fuel, Takeoff/landing distances.

FAR 91.203. Required Certifications (ARROW)

• A - Airworthiness Cert (When the aircraft was originally certified)
• R - Registration Cert (Ensure it isn't expired)
• R - Restricted Radiotelephone Operator's Permit (Only required when operating outside the US)
• O - Operating Limitations (Typically in the aircrafts POH, carry with you when you fly)
• W - Weight and Balance (Found on an aircraft's weight and balance sheet. Calculate weight/balance prior to every flight)
• Supplements and Placards.

FAR 91.303. No persons may operate an aircraft in aerobatic flight:

• Over any congested area of a city, town, or settlement
• Over an open air assembly of persons
• Within the lateral boundaries of the surface areas of Class B, Class C, Class D, or Class E airspace designated for an airport
• Within 4 nautical miles of the center line of any Federal airway
• Below an altitude of 1,500' above the surface

FAR 91.205 Required Day VFR Operative Equipment “A TOMATO FLAMES"

• A - Airspeed Indicator
• T - Tachometer (each engines)
• O - Oil Pressure Gauge (each engine)
• M - Manifold Pressure Gauge (each altitude engine, super/turbo charged)
• A - Altimeter
• T - Temperature Gauge (each liquid cooled engine)
• O - Oil Temperature Gauge (each air cooled engine)
• F - Fuel Gauge (each tank)
• L - Landing Gear Position Indicator (if applicable)
• A - Anti-Collision Lights (red/white)
• M - Magnetic Compass (FAR 25.1547 also requires a compass deviation card)
• E - Emergency Locator Transmitter (ELT)
• S - Safety Belts (every passenger 2 years old and up)

FAR 91.205 Required Night VFR Operative Equipment “A TOMATO FLAMES + FLAPS"

• F - Fuses (1 spare set, or 3 spares for each type required)
• L - Landing Light (1 electric)
• A - Anti-Collision Lights (red/white)
• P - Position Lights (red/green lights on wing edges)
• S - Source of Electrical Power (battery or alternator)

FAR 91.107 Seat Belts

• Each PIC must brief passengers on how to fasten/unfasten safety belts and shoulder harnesses (if applicable)

FAR 91.3 PIC Responsibilities

• PIC has the final authority over their flight and aircraft. PIC may deviate from FARS to meet an emergency situation

FAR 91.203 Compliance with ATC Instructions and Clearances

• Pilots must follow ATC instructions; cannot deviate from ATC clearance without an amended clearance, unless it's an emergency.
• If ATC clearance would cause you to deviate an FAR, disregard the clearance and notify ATC immediately for an amended clearance.

NTSB Part 830

• Notification and reporting of aircraft or incidents, overdue aircraft and preservation of aircraft wreckage and records.
  • Accident: Any persons suffer death or serious injury, or aircraft receives substantial damage.
  • Incident: Occurrence other than an accident, associated with the operation of an aircraft, which affects or could affect the safety of operations.
• Notify NTSB in the event of any of these incidents
  • Flight control system malfunction or failure
  • In flight fire
  • Aircraft collision in flight
  • Damage > $25,000 to property other than the aircraft
  • Release of all or a portion of a propeller blade from an aircraft (except from a ground strike)

METAR (Meteorological Aerodrome Report)

• An observation, not a forecast, being known as an Aviation Routine Weather Report.
• A METAR is valid for 5 nautical miles around an airport
• METARs are issued hourly, valid for 1 hour or until the next report.
• A special METAR (SPECI) can be issued anytime between routine METARS when weather change is significant.
• Use AWC METAR/TAF websites.

How to Read a METAR Weather Report

• Locate the station identifier (airport code)
• Decode the date and time
• Identify the windspeed and direction
• Note the visibility
• Identify precipitation, cloud cover, temperature and dewpoint
• Note altimeter setting, and any remarks.
• Surface chats provide:
  • Location of fronts and pressure systems.
  • The US low level significant weather prog chart is valid up to 24,000'.
• Flight Station (FSS) 122.2 Freq is the primary source for preflight weather information.
  • Additionally, call 1-800-WX-BRIEF or go to 1800wxbrief.com and notify the briefer whether the flight is VFR or IFR.
• Outlook Briefings are for when departures are greater than or equal to 6 hours away.
• Data link weather services are often included with GPS and EFB cockpit or tablet display system.

This content covers the main drivers of atmospheric circulation, focusing on unequal heating from the sun. Key concepts include atmospheric pressure changes with elevation, relative humidity, dewpoint, and the processes of evaporation, condensation, and sublimation affecting air moisture.