The US Federal Aviation Administration has issued two further airworthiness directives (AD) in as many weeks effecting the Embraer ERJ-135/145, mandating inspections and modifications to the aircraft's fuel tank coupling and electrical pump wiring.
The two largest operators of the ERJ-135/145, American Eagle and Continental Express, have both found problems effecting their regional jets. "Some fuel pumps have needed to be replaced and we are following the AD and making ongoing inspections ," says Eagle.
FAA action follows the release in August of two service bulletins (SB) by the Brazilian manufacturer. The first concerns reported damage to the pins and elastomeric inserts in the hermetically sealed wire connectors of the electrical fuel pumps in the main wing tanks.
Whereas Embraer's SB advised replacement of the pump where more than 30% of the wire connector pin is blackened, the AD mandates replacement if any discrepancies are found due to the danger of an ignition source to the fuel tank. The FAA also requires regular inspections "at an interval not to exceed 400h."
The second AD focuses on the Gamah coupling to the fuel tank, where there have been at least two instances of failure, one while an ERJ-145 was landing, resulting in over 1,000lb (454kg) of fuel being spilled on to the runway. The AD stipulates a one-time inspection of the coupling's hinge and locking fastener.
"Once this was brought to light on the Gamah coupling, Embraer sent mechanics in. We did not experience any problems until we went through the inspections and found some instances that needed attending to," says Express.
The ADs follows an FAA mandated emergency inspection of the full authority digital engine control of the ERJ-135/145's Rolls-Royce AE3007 engine. The manufacturer had found that faulty transistors were causing uncommanded engine shut downs.
Source: Flight International