Airworthiness Directive · Amendment 39-9567 · Hamilton Standard Model 14RF-9 Propellers
Hamilton Standard Model 14RF-9 Propellers
Hamilton Standard Model 14RF-9 propellers, installed on but not limited to Embraer EMB-120 series aircraft. Note: This airworthiness directive (AD) applies to each propeller identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For propellers that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must use the authority provided in paragraph (d) to request approval from the Federal Aviation Administration (FAA). This approval may address either no action, if the current configuration eliminates the unsafe condition, or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any propeller from the applicability of this AD.
This amendment adopts a new airworthiness directive (AD) that is applicable to Hamilton Standard Model 14RF-9 propellers. This action supersedes priority letter AD 95-24-09 that currently requires a one- time ultrasonic shear wave inspection of the propeller blade shank for cracks or surface indications. This action continues to require an ultrasonic shear wave inspection, but adds a one-time visual and fluorescent penetrant inspection and repair of the propeller blade shank for mechanical damage. This amendment is prompted by propeller blade shank visual inspection results on blades that were removed from service as a result of the one-time ultrasonic shear wave inspections. The inspection results showed that minor damage could exist that is not detected by the ultrasonic shear wave inspection. This amendment is also prompted by the development of a method to remove the fiberglass on the blade shank permitting shank inspection and repair procedures. The actions specified by this AD are intended to prevent propeller blade separation due to propeller blade shank cracking, which could result in loss of control of the aircraft.
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
