We [FAA] are superseding an existing airworthiness directive (AD) for certain General Electric Company (GE) CF6-80C2 series turbofan engines.
That AD currently requires replacement of the fuel tube connecting the flowmeter to the integrated drive generator (IDG) fuel-oil cooler and the fuel tube(s) connecting the main engine control (MEC) or hydromechanical (HMU) to the flowmeter, with improved fuel tubes.
This new AD requires the same actions, requires installation of a new simplified one-piece supporting bracket, adds an engine model, alters the list of affected part numbers (P/Ns), changes the replacement schedule, and revises our estimated cost of compliance. This AD was prompted by several additional reports of fuel leaks and two reports of engine fire due to improper assembly of supporting brackets on the fuel tube connecting the flowmeter to the IDG fuel-oil cooler.
We are issuing this AD to prevent high-pressure fuel leaks caused by improper seating of fuel tube flanges, which could result in an engine fire and damage to the airplane.
This AD is effective May 31, 2013.