Department of Transportation December 6, 2013 – Federal Register Recent Federal Regulation Documents

We propose to adopt a new airworthiness directive (AD) for certain Bombardier, Inc. Model DHC-8-102, -103, -106, -201, -202, -301, -311, and -315 airplanes. This proposed AD was prompted by reports of a fractured wing-to-fuselage strut attachment joint bolt. This proposed AD would require doing a torque check of all wing-to-fuselage strut attachment joint bolts, and repairing or replacing if necessary. For certain airplanes this proposed AD would require a detailed inspection for corrosion, damage, and wear of each wing-to-fuselage strut attachment joint bolt and associated hardware, and replacing if necessary; and a borescope inspection for corrosion and damage of the bore hole and barrel nut threads, and repairing or replacing if necessary. We are proposing this AD to detect and correct fractured bolts, which could result in reduced structural integrity of the wing- to-fuselage strut attachment joint and subsequent loss of the wing.

We propose to supersede airworthiness directive (AD) 84-19-01, which applies to certain The Boeing Company Model 747-100, 747-200B, 747-200F series airplanes. AD 84-19-01 requires repetitive inspections for cracking of certain tension ties, and repair and certain modifications if necessary. Since we issued AD 84-19-01, the upper deck tension ties have been identified as structure that is susceptible to widespread fatigue damage (WFD), and additional action is necessary for certain airplanes to adequately address the identified unsafe condition on the fleet. This proposed AD is intended to complete certain mandated programs intended to support the airplane reaching its limit of validity (LOV) of the engineering data that support the established structural maintenance program. For certain airplanes, this proposed AD would add inspections for cracking of the tension tie at body station (BS) 760 or 780, corrective action if necessary, and eventual modification of the tension ties. For all airplanes, this proposed AD would require repetitive post-modification inspections for cracking of the tension tie at BS 760 or 780, and corrective action if necessary. We are proposing this AD to detect and correct tension tie cracking, which could eventually result in in-flight depressurization of the airplane and the inability to withstand current regulatory failsafe loads.

This action proposes to amend Class E Airspace at Morrisville, VT, as the Morrisville-Stowe Non-Directional Beacon (NDB) has been decommissioned, requiring airspace redesign at Morrisville-Stowe State Airport. This action would enhance the safety and airspace management of Instrument Flight Rules (IFR) operations at the airport. This action also would update the geographic coordinates of the airport.