Narrative:

Aircraft arrived with 2R door leak. The procedure in MM 51-11-00-6 to check for leaks is impossible to comply with; company doesn't stock the vacuum blankets; generator; nor the ultra sonic leak probe necessary for the task. All door and window leaks; in the past; where checked by pressurizing the aircraft. This is how I answered the 2R leak pirep. Revise the MM to allow pressurizing the cabin as a suitable alternative.callback conversation with reporter revealed the following information: reporter stated the vacuum blankets are place around the suspect leaking door or cockpit sliding window and the vacuum generator is used to create a vacuum. The ultra sonic leak probe is basically used as a noise meter. Any air leaking is measured and compared against a 'leak' tolerance scale to determine if the aircraft can be dispatched as within acceptable limits. Reporter stated that because his carrier does not stock the necessary equipment; they use their previous procedures of pressurizing the cabin interior and placed their hands around all the door and window seals to 'feel' for any air escaping the aircraft. When using the cabin pressurization procedure to check for leaks; their policy does not allow any leaks and the cause must be fixed. Reporter stated that half of all pilot reports of pressure leaks; whistles or squeals suspected to be coming from cockpit windows on their B757's and B767's are actually caused by pressure leaks at the angle of attack (aoa) vanes located at he left and right cockpit sidewalls. Cockpit/cabin air pressure can be felt blowing out for aoa mounting fixture.

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Original NASA ASRS Text

Title: A Mechanic working an inbound B757-200 with a cabin door 2R pressure leak; reports the MM 51-11-00-06 procedure to check for leaks; is impossible to comply with. Suggests revising the MM to allow pressurizing the cabin as a suitable alternative.

Narrative: Aircraft arrived with 2R door leak. The procedure in MM 51-11-00-6 to check for leaks is impossible to comply with; company doesn't stock the vacuum blankets; generator; nor the ultra sonic leak probe necessary for the task. All door and window leaks; in the past; where checked by pressurizing the aircraft. This is how I answered the 2R leak Pirep. Revise the MM to allow pressurizing the cabin as a suitable alternative.Callback conversation with reporter revealed the following information: Reporter stated the vacuum blankets are place around the suspect leaking door or cockpit sliding window and the vacuum generator is used to create a vacuum. The Ultra Sonic leak probe is basically used as a noise meter. Any air leaking is measured and compared against a 'leak' tolerance scale to determine if the aircraft can be dispatched as within acceptable limits. Reporter stated that because his carrier does not stock the necessary equipment; they use their previous procedures of pressurizing the cabin interior and placed their hands around all the door and window seals to 'feel' for any air escaping the aircraft. When using the cabin pressurization procedure to check for leaks; their policy does not allow any leaks and the cause must be fixed. Reporter stated that half of all pilot reports of pressure leaks; whistles or squeals suspected to be coming from cockpit windows on their B757's and B767's are actually caused by pressure leaks at the Angle of Attack (AOA) vanes located at he left and right cockpit sidewalls. Cockpit/cabin air pressure can be felt blowing out for AOA mounting fixture.

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.