Change status of water
July 26, 2025
#Solid #liquid #gas #melting #evaporation #condensation #freezing #sublimation #deposition
點解會落雹 What’s hail?
July 26, 2025
話說琴晚黃昏就收到天文台特別天氣提示話會落雹可能，難道有冤情？ 🙂 都可能係 就係點解我仲未做到飛機師 因為我讀書未夠？ 咁就溫下書～ Hail is formed in strong thunderstorms when supercooled water droplets freeze onto ice pellets, which are then carried by powerful updrafts within the storm cloud. These ice pellets, or hailstones, grow larger as they repeatedly collide with more supercooled water droplets, eventually becoming too heavy to be supported by the updraft
Learn from mistakes: Plane crashes into the Mountain
July 22, 2025
每日學一點點 加油💪🏻 https://youtu.be/11WD64pgyH8?si=XI9gMslExoakfYz- AI summary : American Airlines Flight 965, a Boeing 757, crashed into a mountain near Cali, Colombia, on December 20, 1995, resulting in 151 fatalities. The primary cause was pilot error leading to the aircraft deviating from its intended approach path and impacting terrain. Contributing factors included crew misinterpretations of flight management system (FMS)
Cloud formation: Bergeron-Findeisen theory (Icing) v.s Coalescence theory (Water droplet)
July 20, 2025
https://youtu.be/6WjU0kwu_ew?si=Kvf5LqleDUzpKo8b Cloud Formation
Cloud Formation
July 20, 2025
https://youtu.be/q87Ekar3emA?si=EN2zl3qUX1OmIcsh Cloud formation occurs when warm, moist air rises, cools, and loses its ability to hold water vapor. As the air cools, the water vapor condenses into tiny water droplets or ice crystals, forming clouds. Read More https://www.britannica.com/video/process-cloud-formation-factors-surface-air-water/-203821 Cloud formation: Bergeron-Findeisen theory (Icing) v.s Coalescence theory (Water droplet) Cloud formation 夠竟係吸定放latent heat? Clouds 雲
Oktas – reporting the amount of cloud in the sky
July 20, 2025
https://worldweather.wmo.int/oktas.htm Oktas Definition Category 0 Sky clear Fine 1 1/8 of sky covered or less, but not zero Fine 2 2/8 of sky covered Fine 3 3/8 of sky covered Partly Cloudy 4 4/8 of sky covered Partly Cloudy 5 5/8 of sky covered Partly Cloudy 6 6/8 of sky covered Cloudy 7 7/8 of
How Does Autopilot Work? A Pilot Explains What It Can and Can’t Do
July 20, 2025
https://www.wsj.com/video/series/travel-guides/how-does-autopilot-work-a-pilot-explains-what-it-can-and-cant-do/1C1E2CD3-92E3-420F-927B-5A4026A3E412?mod=hp_featst_pos5
點解ATIS 要點Temperature and Dew Point?
July 20, 2025
今日打風溫書…簡接溫故知新~ 下面有個ATIS 實例…有T 28 /DP 26 要推算Cloud Base = T-DP * 400 = (28-26)*400 = 2* 400 = 800 feet AGL 再反推Relative Humidity (RH) = 100 – (T-D) *5 = 100 – (28-26) * 5 = 100 – 10 = 90% 呢兩條Rule of thumb 係work 既~
Calculation of Freezing Height
July 20, 2025
The Bradbury Rule Example: OAT 10 degree C ; DP 7 degree C Calculate Cloud Base T – DP * 400 = (10-7) * 400 = 1200 feet AGL Calculate Freezing layer DP / 1.8 * 1000 = 7/1.8 * 1000 = 3889 feet AGL Freezing height 1200 + 3889 = 5089 feet AGL This
How to find the Dew Point? How to find Relative Humidity (RH)?
July 20, 2025
How to find the Dew Point? RH = 100 – (T-D) x 5 Example: RH 83% ; Temp 12C, then 83 = 100 – (12-D) x 5 (83-100) / (-5)= 12-D D = 12 – (83-100) / (-5) D = 8.6 degree C Rightly, we can interpret the relative humidity (find the RH) from
Dew Point Application – Calculate Cloud Base
July 20, 2025
Degree C Let’s say the temperature is 25°C and the dew point is 15°C. Convergence Rate (CR) = 2.5°C Temperature Dew Point Spread (TDS) = T-DP = 25 – 15 = 10°C TDS ÷ CR = 10 / 2.5 = 4 Multiply by 1000 = 4 * 1000 = 4000 feet Therefore, the estimated cloud
Dew point, Dew Point Spread
July 20, 2025
What’s Dew Point? Dew point, given in degrees, is the temperature at which the air can hold no more moisture. When the temperature of the air is reduced to the dew point, the air is completely saturated and moisture begins to condense out of the air in the form of fog, dew, frost, clouds, rain,
ISA Deviation
July 20, 2025
Example: FL290 ; OAT -47 degree C ISA standard = 15 – (feet /1000) * 2 ISA Deviation = OAT – ISA standard FL 290 : 29,000 feet, so ISA standard @ FL 290 = 15- (29*2) = -43 degree C ISA deviation = -47 – -(43) = ISA-4 degree C https://youtu.be/_oWqu12Dm6M?si=eUYvJoTQD_EOKKl2
Thermodynamics: Radiation, Conduction, Convection & Advection
July 20, 2025
https://youtu.be/0vdxlgRKx1k?si=a80FzWfEp2fsKj2K What’s Solar insolation?
Tropopause
July 20, 2025
What’s Tropopause? https://youtu.be/jTCWSjhhXgc?si=9Zf8eVJgx6TKOXDs Tropopause height and its significance? https://youtu.be/ZfGVHCJSDsw?si=qaqwuN4DSlX6uyiu https://youtu.be/dRI5gYrJmvo?si=NHQo3NtST_5f-9ei More Reference: https://code7700.com/tropopause.htm
Spiral Dive v.s Spin v.s Dutch Roll
July 12, 2025
好耐無溫書…係時候準備! 今日朋友講起呢兩個TOPIC…就睇下啦~ XDDD Spin Stall -> Spin (autorotation) BOTH wing stall, but one wing stall more -> i.e uncoordinated stall / imbalanced stall 3 Phases (2 mins 36 sec) Incipient Spin Fully developed Recovery Feature slow airspeed at fully developed stage + high AOA Factors affecting spin recovery Weight & Balance -> CG aft, more
Air India crash : comment and discussion by Firstpost
July 1, 2025
https://youtu.be/dKeSj46pzng?si=X9U1pcfLMhu-jD4T d英文都幾易聽 內容都充實 對事情做個初步評估推論外 又有提到一班機pf 同 pm 既分別、 CVR 同 FDR 既分別 值得bookmark
