Pilot Licences
March 16, 2024
HKCAD – Hong Kong Civil Aviation Department Pilot Licences https://www.cad.gov.hk/english/ppl.html We need to prepare our self to be competent as an airline crew with various requirements at different stage, although the CX application page concludes in 6 points briefly: A Hong Kong Permanent resident Graduated from secondary school with good passes in English language, Mathematics
點樣知機場QNH? 點樣知Local Pressure? How to know the QNH? How to know local pressure?
March 16, 2024
今日上完堂再唸左成個下午先好D 通左D, 所以一定要記底佢…小喇叭, 呢個Concept 好難明! Anyway, mark 低佢先! Reading (in feet) = (Set QNH – Actual pressure level) * 30 For example, if the aerodrome is 30 feet Elevation and 當時QNH是1013, then Reading (in feet) = (Set QNH – Actual pressure level) * 30 30 = ( 1013 – Actual pressure level )＊ 30 30/30
Why “Fly to low, watch below ; High to cold, watch below” ?
March 4, 2024
Ref Ace the technical pilot interview 2/E Ans: Always remember : aneroid barometer is working based on MSL pressure (i.e pressure height) ! 1. FL formula Flight Level (Pressure Height) in feet = Height @ QNH + (1013 – QNH) * 30 Example: Now say 300 feet @ 1025 PH = 300
Maximum Glide Range?
February 29, 2024
Ans : two manoeuvre factors – 1. optimal angle of attack 2. minimum drag speed 當上面兩樣野做到又吾計wind , 理論上隻機就會飛 @ max L/D ratio 記著： 重量同max glide range 無關！ 取決上面說的兩個操作factors – 大機同細機glide range 一樣 ！
Pilot math
February 29, 2024
計數係惡夢 但方法還是有 🤭 Ref skybrary: https://skybrary.aero/articles/rules-thumb 時間 Time 6 mins 0.1 hour 3 mins 0.05 hour 方位 Reciprocal Heading = HDG +200 – 20 or = HDG – 200 + 20 大過200就- 先 ； 細過200就+ 先 e.g 090 : 90 + 200 – 20 = 270 270 : 270 – 200 + 20
NITS Briefing
February 27, 2024
Ref： https://simpleflying.com/how-pilots-handle-aircraft-failures/ 有d知識或技巧不常用就會忘記 所以要溫書📚 🫣🤗 When executing the decision, all relevant parties must be informed in the proper order. Firstly, the appropriate ATC must be contacted and briefed about your decision to return or divert to another field. Then the lead cabin crew or the purser must be called to the cockpit to be informed
Ground effect 對不同flight status 的影響? (就Ground Effect 有咩係機師要知, 有咩要做?)
February 25, 2024
Ref Ch5 Ans: 機師要記著 – T/O phase not attempt to force the acft T/O with not sufficient takeoff speed (due IAS 假象!) never retract the landing gear or flaps prior to establish +ve rate of climb never retract the landing gear or flaps prior reaching MSA (minimum safe altitude) Landing phase reduce power to
Ground effect 有咩影響? Significance of ground effect?
February 25, 2024
Ref Ch5 Ans: Upwash↓ , downwash ↓ –> Wingtip vortices ↓ –> induced drag ↓ –> AOA need to be reduced for same CL Local pressure on static source [position (installation) error] –> airborne IAS reduce 假象 Induced Drag 成因? What’s ground effect?
What’s ground effect?
February 25, 2024
Ref Ch5 Ans: air cushion phenomenon The reason of ground effect is that the air that is trapped between the wing and the landing surface, as if there were an air cushion. When the plane is very close to the surface (say just before touchdown), it would suddenly feel like the plane did not want
Strategy to avoid wake turbulence?
February 25, 2024
Ref Ch5 Ans: 飛緊 : avoid similar flight path with 1000 ft vertical separation T/O : rotate before the point at which preceding acft rotated LAND : approach above preceding acft’s flight path LAND : touch down after the point where other’s wheel contact If doubt, 用 3 mins margin time (rule of thumb) For
When the wingtip vortices are greatest?
February 25, 2024
Ref Ch5 Ans: heavy, clean, slow Vortices 正比 Weight Vortices 反比 Wingspan Vortices 反比 Speed 所以大機, 無落FLAPS, TAKE OFF/APPROACH 果陣最勁~ 因為大機重, 無FLAPS 要產生升力, AOA 自然大, INDUCED DRAG as well as Wingtip vortices 就當然大 Reference: https://aviation.stackexchange.com/questions/52762/how-can-larger-wingspan-decrease-the-strength-of-wingtip-vortices
點解vortices 係 wingtip ? The formation of wingtip vortices~
February 25, 2024
Ref Ch5 Ans: pressure differential (between upper and lower surfaces of wing) air always moves from high pressure toward low pressure bottom : span-wise movement of air (outward from fuselage to and around tips) upper surface : span-wise movement (flow in toward fuselage and off the trailing edge) fuselage limits the inward flow –
Induced Drag 成因?
February 22, 2024
Ref Chapter 5 Ans: air tends to flow from the high pressure area to low pressure area higher pressure at the bottom of airfoil vortices is created (at wing tip) – wingtip vortices vortices roll off, and create a downwash downwash points the relative wind downward lift is tilted the more the tilted lift, the
What’s Induced Drag?
February 22, 2024
Ref Chapter 5 Ans: inherent drag due to lift production. Induced drag is inherent whenever an airfoil is producing lift and, in fact, this type of drag is inseparable from the production of lift. Consequently, it is always present if lift is produced. AOA increases, induced drag increases proportionally When view from the tail
What’s boundary layer?
February 22, 2024
Ref Chapter 5 Ans: the layer of air between the wing and free-stream velocity level The area between the wing and the free-stream velocity level is about as wide as a playing card and is called the boundary layer.
Free-stream velocity?
February 22, 2024
Ref Chapter 5 Ans: the speed at which molecules are moving at the velocity that same as the air moving around the aircraft. Each layer of molecules above the surface moves slightly faster until the molecules are moving at the velocity of the air moving around the aircraft. This speed is called the free-stream
Skin friction Drag?
February 22, 2024
Ref Chapter 5 成因: contact of moving air with the surface of an aircraft 解決／緩解方法： flush mount rivets remove any irregularities that may protrude above the wing surface smooth and glossy finish remove dust and dirt no matter how apparently smooth, has a rough, ragged surface when viewed under a microscope
Interference Drag?
February 22, 2024
Ref Chapter 5 成因: intersection of airstreams （that creates eddy currents, turbulence, or restricts smooth airflow） 解決／緩解方法： Fairings most interference drag is observed when two surfaces meet at perpendicular angles （e.g wing and wing root)
Form Drag?
February 22, 2024
Ref Chapter 5 成因: shape and airflow around the airfoil (aircraft) 解決／緩解方法： streamline (as many of the parts as possible) When the air has to separate to move around a moving aircraft and its components, it eventually rejoins
