Narrative:

I was on duty in maintenance control when a call was received for skydrol leak in # 1 engine nacelle. Leak was found to be in an aluminum hydraulic line which ran from the top of the nacelle to the # 1 spoiler unloading valve. Attempts to run a temporary flex line failed. The cockpit shutoff switches for the inboard spoilers were reported to 'not' stop the leak. A ferry flight was set up but the captain didn't feel comfortable with the leak rate. I then thought that plugging and capping the affected line would stop the leak; believing that only the inboard spoilers would be affected.I typed up and had approved a ferry permit to plug and cap the line and tape down the inboard spoilers as a precaution because the spoilers would not have fluid to prevent movement. This was completed and sent; the actions were in progress when shift turnover occurred. The event was obvious when the dhc-8-100 aircraft didn't have serviceable brakes. When the aircraft moved from gate; flight crew discovered the toe brakes were not working. The mechanics then re-connected the capped and plugged line. A new ferry permit was issued and the aircraft flew without incident.the incident occurred because I was using a figure from the parts manual (the maintenance manual didn't show the setup of hydraulic lines in the nacelle). It was also discovered that the spoiler shutoff switches in the cockpit 'did' stop the leak and that was the basis of the new ferry permit. The event occurred because of misinterpretation of the manual and mis-information between myself and the mechanics. The line was reconnected; the leak was determined to be stopped by selecting spoiler switches 'off' and a new ferry permit was issued.proper interpretation of the maintenance manual aided by the parts manual and better communication between maintenance control and the mechanics.

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Original NASA ASRS Text

Title: A Maintenance Controller describes the efforts by mechanics to stop a hydraulic line from leaking skydrol fluid in the # 1 engine nacelle of a DHC-8-100 allowing him to issue a ferry permit to have the aircraft flown to a maintenance base. During taxi-out; flight crew discovered toe brakes were not working.

Narrative: I was on duty in Maintenance Control when a call was received for skydrol leak in # 1 engine nacelle. Leak was found to be in an aluminum hydraulic line which ran from the top of the nacelle to the # 1 spoiler unloading valve. Attempts to run a temporary flex line failed. The cockpit shutoff switches for the inboard spoilers were reported to 'not' stop the leak. A ferry flight was set up but the Captain didn't feel comfortable with the leak rate. I then thought that plugging and capping the affected line would stop the leak; believing that only the inboard spoilers would be affected.I typed up and had approved a ferry permit to plug and cap the line and tape down the inboard spoilers as a precaution because the spoilers would not have fluid to prevent movement. This was completed and sent; the actions were in progress when shift turnover occurred. The event was obvious when the DHC-8-100 aircraft didn't have serviceable brakes. When the aircraft moved from gate; flight crew discovered the toe brakes were not working. The mechanics then re-connected the capped and plugged line. A new ferry permit was issued and the aircraft flew without incident.The incident occurred because I was using a figure from the Parts Manual (the Maintenance Manual didn't show the setup of hydraulic lines in the nacelle). It was also discovered that the spoiler shutoff switches in the cockpit 'did' stop the leak and that was the basis of the new ferry permit. The event occurred because of misinterpretation of the Manual and mis-information between myself and the mechanics. The line was reconnected; the leak was determined to be stopped by selecting spoiler switches 'Off' and a new ferry permit was issued.Proper interpretation of the Maintenance Manual aided by the Parts Manual and better communication between Maintenance Control and the mechanics.

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.