Federal Aviation Administration March 12, 2013 – Federal Register Recent Federal Regulation Documents

These final special conditions are issued for the General Electric Aviation (GE) CT7-2E1 engine model. This engine model will have a novel or unusual design feature, which is a combination of two existing ratings into a new rating called ``flat 30-second and 2-minute OEI'' rating. This rating is intended for the continuation of flight of a multi-engine rotorcraft after one engine becomes inoperative. The applicable airworthiness regulations do not contain adequate or appropriate safety standards for this design feature. These final special conditions contain the additional safety standards the Administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards.

We are revising an earlier proposed airworthiness directive (AD) for certain Bombardier, Inc. Model DHC-8-400, -401, and -402 airplanes. That NPRM proposed to require an inspection to determine if certain rudder feel trim units (RFTUs) are installed, an operational check for signs of seizure of affected parts, repetitive lubrication for certain RFTUs, and replacement of the RFTU if necessary. Installing replaced RFTUs with conformal bushings would terminate the repetitive lubrication requirements. That NPRM was prompted by reports of movement of the rudder pedals being impeded due to corrosion of the trunnion shaft of the RFTU. This action revises that NPRM by reducing compliance times, increasing compliance costs, expanding affected parts to include additional serial numbers and include those parts with a suffix `A,' and adding the condition of rough movement to the operational check. We are proposing this AD to detect and correct any sign of rough movement or seizure of the trunnion shaft and its bushing, which could cause a rudder control jam or a large and rapid alternating rudder input leading to a structural failure of the vertical fin. Since these actions impose an additional burden over that proposed in the NPRM, we are reopening the comment period to allow the public the chance to comment on these proposed changes.

We are adopting a new airworthiness directive (AD) for Sikorsky Aircraft Corporation-manufactured Model S-64F helicopters, now under the Erickson Air-Crane Incorporated (Erickson) Model S-64F type certificate. This AD supersedes an existing AD which requires inspections, rework, and replacement, if necessary, of the main gearbox (MGB) second stage lower planetary plate (plate). Since we issued that AD, the manufacturer has conducted a configuration review and analysis, and a review of the service history of certain components. The actions of this AD are intended to establish life limits for certain components, remove various parts from service, and require consistency in the part numbers of certain four bladed tail rotor (T/R) assemblies to prevent fatigue cracking, failure from static overload, and subsequent loss of control of the helicopter.