Narrative:

Amber alert. Loss of yellow hydraulic system pressure and quantity; thirty miles out; inbound to ZZZ. Found o-ring eroded on the union attached to the parking brake valve. (Illustrated parts catalog) ipc 32-45-03-3b; item #230. I have the damaged packing; it looks like the material the o-ring was made of is not compatible with skydrol; o-ring just disintegrated; part number NAS-1612-8.

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Original NASA ASRS Text

Title: A Line Mechanic reports finding a deteriorated O-ring at the union attached to the Parking Brake valve after the inbound A320 aircraft loss Yellow Hydraulic System pressure and quantity. O-ring appeared to be made of material not compatible with Skydrol type hydraulic fluid.

Narrative: Amber alert. Loss of Yellow Hydraulic System pressure and quantity; thirty miles out; inbound to ZZZ. Found O-ring eroded on the union attached to the parking brake valve. (Illustrated Parts Catalog) IPC 32-45-03-3b; Item #230. I have the damaged packing; it looks like the material the O-ring was made of is not compatible with Skydrol; O-ring just disintegrated; Part Number NAS-1612-8.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.