Narrative:

A pilot reported that the right side of aircraft was resting low. After performing an X [cylinder] dimension check and referring to the maintenance manual; it was determined the left main landing gear strut X [cylinder] dimension was too high and the right main landing gear strut was too low. During the servicing of the right main landing gear strut; the nitrogen depleted to the point that fluid began to escape from the schrader valve on top of the strut. I noticed the discoloration of the hydraulic fluid (military-H-5606) and the fact that it lacked any color of red to it. The fluid that came out was grey and smelled like fuel. Upon identifying the problem; the customer was notified of the findings.

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Original NASA ASRS Text

Title: Maintenance personnel report that on several occasions they have found Lear jet landing gear struts serviced with jet fuel rather than hydraulic fluid.

Narrative: A pilot reported that the right side of aircraft was resting low. After performing an X [cylinder] dimension check and referring to the Maintenance Manual; it was determined the left main landing gear strut X [cylinder] dimension was too high and the right main landing gear strut was too low. During the servicing of the right main landing gear strut; the nitrogen depleted to the point that fluid began to escape from the Schrader valve on top of the strut. I noticed the discoloration of the hydraulic fluid (MIL-H-5606) and the fact that it lacked any color of red to it. The fluid that came out was grey and smelled like fuel. Upon identifying the problem; the customer was notified of the findings.

Data retrieved from NASA's ASRS site as of July 2013 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.