A Line Mechanic reports a First Officer found evidence of fuel leaking inside the left wheelwell of an ERJ-190 during preflight. After applying sealant to the suspected area; Mechanic signed-off the write-up. He is informed later; the aircraft should have been ferried or grounded.
Synopsis
A Line Mechanic reports a First Officer found evidence of fuel leaking inside the left wheelwell of an ERJ-190 during preflight. After applying sealant to the suspected area; Mechanic signed-off the write-up. He is informed later; the aircraft should have been ferried or grounded.
Narrative
Flight Crew; during walk around; found evidence of fuel leak inside of left wheel well. First Officer showed me what he found. I saw some fuel droplets on hydraulic line clamp bundle. Looked to see where the leak could be coming from. In the wheel well; the bottom of wing-to-body fairing was dry; looked through opening between the bottom of fuel tank and fairing did not see any fuel on bottom of tank. I opened door on the bottom of fairing to take another look of the area. Did not see any fuel in this area. Went back to Shop; got a ladder to look at the left-hand edge of tank from top to bottom edge. No leak noticed in this section of tank; but did find a small area at bottom of tank at the lower outboard section. This area has fasteners that attach the bottom to aft spar; no leaks at any fastener; only where the sealant was applied to the outer edge where the aft spar and bottom of the fuselage joined together. After finding this; I called Maintenance Operations for guidance and possible fix to this discrepancy. Took awhile for Maintenance Operations to find a reference to use; Chapter (28-11-00); I cleaned area and applied sealant to area where fuel leak was found. After putting up equipment and signing Logbook; went back and checked area to make sure no fuel was leaking. No leak noted.My lack of knowledge of the allowable fuel leakage in wheel well area and a lack of communication between me and Maintenance Operations were some of the causes; plus I was under some pressure to keep departure delay to minimum.In the future; any fuel leaks in wheel well need to be fixed; no matter how small they are.
NASA callback
Reporter stated the leak area inside the left wheelwell already had a heavy amount of sealant under the painted lower skin and fuselage. The fuel seepage was difficult to locate. He did not defer the First Officer's fuel leak; but signed off the Logbook write-up; after re-sealing the lower wing skin root to fuselage area with a product called PRC sealant. Reporter stated even though Maintenance Operations was OK with his sign off; he was informed later the aircraft should have been ferried back to Base or grounded; so Maintenance could go inside the fuel tanks; locate the fuel leak and most likely re-seal from inside the tank.Reporter stated the issue was his releasing an aircraft without knowing the source of the leak and what areas have fuel leak limitations. The ERJ-190 was later removed from service for fuel tank work.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.