之前有人問SUSPECTED FUEL LEAK 有咩要做?
第一件事我地要會知Fuel leak? But How?
正常我地每次飛, 每30分鐘都要做fuel check, 要monitor fuel consumption; 咁先可以盡早發現fuel leak.
Airbus 有ECAM; 通常fuel imbalance 會係一個ECAM . 因為好小Leak from both tanks, 所以如果有Fuel imbalance, 唔好心急 ECAM action,開 crossfeed. Identify 無fuel leak 先好開!
除左Imbalance之外,仲有咩方法/hints知道fuel leak?
A fuel leak may be detected by:
‐ The sum of FOB and FU is significantly less than FOB at engine start, or is decreasing, or
‐ A passenger observes a fuel spray from an engine/pylon, or a wing tip, or
‐ The total fuel quantity is decreasing at an abnormal rate, or
‐ A fuel imbalance is developing, or
‐ Fuel quantity of a tank is decreasing too fast (leak from engine/pylon, or hole in a tank), or
‐ A tank is overflowing (due to pipe rupture in a tank), or
‐ The Fuel Flow is excessive (leak from engine), or
‐ Fuel is smelt in the cabin.
If visibility permits, leak source may be identified by a visual check from the cabin.
WHEN A LEAK IS CONFIRMED LAND ASAP
即刻搵地方Divert, 因為未搵到leak source同isolate source 之前, 你唔知部機仲可以飛幾耐~
之後就要搵leak source 同isolate 個source (from the Tank?the pipeline? within the engine?)
搵到leak source, 停左個leak 先可以知到部機重有幾多usable fuel 同 重可以飛幾耐~
如圖, 有d case 我地要shutdown 個engine 先可以identify 到 leak source( engine or tank)
真係要冷靜處理~開錯crossfeed 就 fuel starvation!
下個ACI 講Air Transat Flight 236 好唔好?
留下言la~
Thank you for the explanation! Indeed support and Looking forward to Air Transat Flight 236 ACI post! Interesting accident where the trim tank design of Airbus misleads the pilots from recognising the fuel leak.
First follow-up question is about the single-engine operation, when one of the engines is suffered from fuel starvation due to the wing tank leak on one side, would it affect the manoeuvrability of the aircraft and hence need to increase the VMCa/VMCg or even need a higher Vref on landing? (because you may need extra aileron deflection to counteract the weight imbalance + asymmetric thrust at the same time, terrible!!!) Secondly, I am a bit confused with the leak source identify flow (of a fuel leak), maybe I write it out first: Engine/Pylon --> Wing Tank --> Centre Tank / Trim Tank / APU Feed Line, please correct me if I am wrong.
A term Fuel Loss Reduction has been mentioned in the QRH for a few times, what can actually pilots do inflight to reduce fuel loss apart from isolating the leak source?
Furthermore, the QRH shows that DO NOT use reversers for LDG, I understand that using the fuel leak side's reverser may spread the fuel leak further or in the worst case cause a fire. But why can't we use the remaining reverser? As it is still useful for landing deceleration.
Finally, in cruise, besides fuel checking, is there any other figure (maybe FL or weather-related ?) do pilots need to check for? Those checking procedures would usually be completed by PF or PM?