Federal Aviation Administration April 3, 2007 – Federal Register Recent Federal Regulation Documents

We propose to supersede Airworthiness Directives (AD) 93-07-11 and AD 94-04-16, which apply to certain Mitsubishi Heavy Industries MU- 2B Series airplanes. AD 93-07-11 and AD 94-04-16 currently require you to reduce the maximum deflection of the elevator nose-down trim to a 1- degree to 3-degree range. When the above AD actions were issued, there was no associated elevator trim indicator change. Without such change, the trim reaches the maximum nose-down limit and the indicator still shows additional nose-down trim available. In attempting to force additional nose-down trim, pilots have manually jammed the trim system preventing subsequent electric trim changes until the pilot manually freed the trim wheel. Consequently, this proposed AD would retain the actions from AD 93-07-11 and AD 94-04-16 and add the action of modifying the elevator trim indicator scale dial to be consistent with the reduced elevator trim capability. We are proposing this AD to prevent the above scenarios from occurring with consequent loss of control.

This technical amendment corrects a final rule published in the Federal Register on July 24, 2006 (71 FR 41727), Docket No. FAA- 2005-23157, Airspace Docket No. 05-ANM-15. In that rule, the reference to FAA Order 7400.9 was published as FAA Order 7400.9O. The correct reference is FAA Order 7400.9P. Also, the corresponding date that refers to the date the Order was signed was omitted. The final rule should state ``* * * dated September 1, 2006 * * *'' (prior to the effective date), instead of ``* * * updated yearly * * *'' This technical amendment corrects those errors.

This amendment establishes, amends, suspends, or revokes Standard Instrument Approach Procedures (SIAPs) and/or Weather Takeoff Minimums for operations at certain airports. These regulatory actions are needed because of the adoption of new or revised criteria, or because of changes occurring in the National Airspace System, such as the commissioning of new navigational facilities, addition of new obstacles, or changes in air traffic requirements. These changes are designed to provide safe and efficient use of the navigable airspace and to promote safe flight operations under instrument flight rules at the affected airports.

The FAA is adopting a new airworthiness directive (AD) for all Boeing Model 777 airplanes. This AD requires a one-time inspection to determine the part number of the left and right air supply and cabin pressure controllers (ASCPCs) and installation of new ASCPC software if necessary. This AD results from a report of an ASCPC failure during flight. We are issuing this AD to prevent an ASCPC failure that could stop airflow into the airplane, inhibit the cabin altitude warning message, and cause an incorrect display of cabin altitude. These failures could result in depressurization of the airplane without warning.

The FAA is superseding an existing airworthiness directive (AD), which applies to certain Airbus Model A318-100, A319-100, A320- 200, A321-100, and A321-200 series airplanes; and Model A320-111 airplanes. That AD currently requires modification of the electrical bonding of all structures and systems installed inside the center fuel tank. This new AD requires modification of additional bonding points inside the center fuel tank. This AD results from a report that additional bonding points need to be modified in order to prevent electrical arcing in the center fuel tank. We are issuing this AD to prevent electrical arcing in the center fuel tank due to inadequate bonding, which could result in an explosion of the center fuel tank and consequent loss of the airplane.

This draft letter of interpretation addresses a request by the Aircraft Owners and Pilots Association (AOPA) that the FAA rescind a letter of interpretation dated June 6, 2006 regarding ``known icing conditions''. Because of the controversy surrounding this issue, the FAA is publishing a draft of its response to seek public comment.