Corrosion Prevention and Control Program (以下簡稱 CPCP)
一、目的
為控制飛機結構腐蝕在Level 1以下,當結構腐蝕有超過Level 1 (亦即發生Level 2或Level 3 corrosion)之情形,必須依評估結果決定相關修正措施,如調整該機型之維護計劃、工作程序單、防腐防鏽劑的選用及結構清洗等方式以控制腐蝕狀況在Level 1以內,若放任不管將可能發生飛安事件的危害。
二、定義:
LEVEL 1 結構腐蝕:
Corrosion occurring between successive inspections that is local and can be reworked/blended-out within manufacturers' allowable limits (e.g., SRM, Service Bulletin, etc.). or
Corrosion occurring between successive inspections exceeds allowable limit but is local and can be attributed to an event not typical of operator usage of other aircraft in the same fleet (e.g., Mercury spill).or
Operator experience over several inspections has demonstrated only light corrosion between each scheduled inspection but the latest inspection and cumulative blend-out now exceeds allowable limits.
LEVEL 2 結構腐蝕:
Corrosion occurring between successive inspections that requires a single re-work/blend-out which then exceeds allowable limits, requiring a repair/reinforcement. or
Corrosion occurring between successive inspections that is widespread and requires a single blend-out approaching allowable rework limits.
LEVEL 3 結構腐蝕:
Corrosion found during the first or subsequent inspections, which is determined (normally by the operator) to be an urgent airworthiness concern, requiring expeditious action.
三、適用範圍:
各機型之機體結構,包括艙門結構、機身蒙皮、派龍、垂直安定面、水平安定面及機翼等。
四、結論
當飛機發現有Level 3 結構腐蝕時,同時須檢視同型機裡的其它飛機是否有相同狀況,以確保其它飛機能及時發現缺點,將其結構腐蝕控制在Level 1以下。
如Level 3 結構腐蝕為單一事件(如載運高腐蝕性物件),則不需調整維護計劃、工作程序單、防腐防鏽劑的選用及結構清洗等方式來改善。
彙整者:空中勤務總隊 呂政傑
五、參考文獻
※ FAA AD 90-25-05
※ Boeing 777 MPD