Maintenance Airframe; Maintenance Powerplant
Communication Breakdown; Confusion; Situational Awareness
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural FAR
General Maintenance Action
Aircraft; Manuals; Chart Or Publication
There is always a debate on window serviceability when determining limits on acrylic windows. For example; today A B767-300 aircraft had small cracks in the [cockpit] L3 Window [#3 Left]. Our Air Carrier Engineering Document 56-11-00 for B767 aircraft states no V-chips or cracks are permissible in any glass pane. There are no published limits for acrylic windows in our company Engineering Document. Can one assume that glass limits pertain to acrylic; or do acrylic windows have different limits. If so; when do cracks becomes unserviceable in acrylic windows? Suggest [Engineering] clearly define serviceability of acrylic windows in company Engineering Document 56-11-00 for B767; or remove all references to glass; thereby only having a window pane limit regardless of its construction [material].
A Line Mechanic reports that no published serviceability limits exists for V-chips or crack damages in their Engineering Document 56-11-00; for cockpit acrylic windows on B767 aircraft. Only glass window pane damage limits are published; raising question of when do cracks become un-serviceable in acrylic windows.