The polyimide based wire (MIL-W-81381) is still on some aircraft. The industry has learned from this and modern aircraft now use wires that are less prone to electrical arcing. Further, electrical power system circuit protection has advanced to detect and halt these events before they can cause significant damage.
they mentioned at the start the wires were in service for about 25 years in a 747. so the plastic insulation is old to the point that it has become harden and can crack.
Most aircraft wire insulation's will degrade, lose flexibility, and crack or fail in other ways. How long and what conditions are all dependent on the material construction.
An MCB can now be arc fault protected by micro processors built into them.
very useful .Thanks
so this is the wire used in aircraft?
The polyimide based wire (MIL-W-81381) is still on some aircraft. The industry has learned from this and modern aircraft now use wires that are less prone to electrical arcing. Further, electrical power system circuit protection has advanced to detect and halt these events before they can cause significant damage.
they mentioned at the start the wires were in service for about 25 years in a 747. so the plastic insulation is old to the point that it has become harden and can crack.
Most aircraft wire insulation's will degrade, lose flexibility, and crack or fail in other ways. How long and what conditions are all dependent on the material construction.
Could you tell me which standard this wet arc test origined from?
This was AS4373 Method 509