AD 98-25-09 63 FR 68169

This amendment adopts a new airworthiness directive (AD), applicable to certain Bombardier Model DHC-7 and DHC-8 series airplanes, that requires a one-time visual inspection to determine the serial number of the brake shuttle valves of the main landing gear (MLG); and replacement of the filter fittings with new filter fittings, if necessary. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to ensure that proper filter fittings are installed. Installation of improper filter fittings could result in failure of the brake shuttle valves, and consequent loss of brake effectiveness, which could reduce controllability of the airplane during taxi, takeoff, and landing roll.