Airworthiness Directive · Amendment 39-9420 · Hamilton Standard Division, Hamilton Sundstrand Propellers
Hamilton Standard Division, Hamilton Sundstrand Propellers
This AD applies to Hamilton Standard Division, Hamilton Sundstrand 6/5500/F-1, 6/5500/F-2, 14RF-19, 14RF-21, 14RF-23, 14RF-9, 14SF- 5, 14SF- 7, 14SF-11, 14SF-15, 14SF-17, 14SF-19, 14SF-23, 14SFL11, 247F-1.
The models as the FAA's AD index lists them. The serial ranges, installed parts and exceptions are in the AD itself: read it at the FAA.
This amendment supersedes an existing airworthiness directive (AD), applicable to Hamilton Standard 14RF, 247F, 14SF, and 6/5500/F (formerly Hamilton Standard/British Aerospace 6/5500/F) series propellers, that currently requires initial and repetitive inspections of the propeller control unit (PCU) servo ballscrew internal spline (BIS) teeth for wear, and replacement, if necessary, of PCU servo BIS assemblies. This amendment increases the repetitive PCU servo BIS teeth inspection interval from 1,500 to 2,500 hours time in service (TIS) for propellers that have a ballscrew quill damper installed. In addition, the FAA has reevaluated the optional installation of the Secondary Drive Quill (SDQ), and has added a new compliance end-date of June 30, 1998, for the installation of the SDQ. This AD will also require initial and repetitive torque check inspections of the primary ballscrew quill once the SDQ is installed. This amendment is prompted by field service and laboratory test data that indicate that the repetitive inspection interval can be safely increased, and by the development and availability of the SDQ. The actions specified by this AD are intended to prevent inability to control the propeller blade angle due to tooth wear in the PCU servo BIS assembly.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
Propellers
