AD 96-08-01 Airworthiness Directives; Hamilton Standard Model 14RF-9 Propellers

Models named: 14RF-9. Read the applicability below — it usually turns on serial or part numbers too.

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.

Required as indicated, unless accomplished previously. To prevent propeller blade separation due to propeller blade shank cracking, which could result in loss of control of the aircraft, accomplish the following: (a) Propeller blades that have been ultrasonically shear wave inspected in accordance with the requirements of priority letter AD 95-24-09 need not undergo another ultrasonic shear wave inspection in accordance with paragraph (b) of this AD. All affected propeller blades with S/N's less than 885751, however, must be inspected for mechanical damage in accordance with paragraph (c) of this AD by August 31, 1996. Propeller blades with S/N's less than 885751 that have not been ultrasonically shear wave inspected in accordance with priority letter AD 95-24-09 must undergo ultrasonic shear wave inspection in accordance with paragraph (b) of this AD prior to further flight, and must be inspected for mechanical damage in accordance with paragraph (c) of this AD by August 31, 1996; or must be inspected for mechanical damage in accordance with paragraph (c) of this AD prior to further flight. (b) Prior to further flight, perform an ultrasonic shear wave inspection for cracks or surface indications in accordance with the applicable Hamilton Standard Service Bulletin (SB) or Alert Service Bulletin (ASB) described in paragraphs (b)(1) and (b)(2) of this AD unless accomplished previously in accordance with AD 95-24-09. Prior to further flight, remove from service propeller blades with ultrasonic shear wave readings that exceed the acceptable limits described in the applicable SB or ASB, and replace with serviceable propeller blades: (1) Inspect, and if necessary, remove and replace with a serviceable propeller blade, in accordance with the Accomplishment Instructions of Hamilton Standard SB No. 14RF-9-61-86, Revision 4, dated November 9, 1995, propeller blade shanks with propeller blade spars, Part Number (P/N) 792231-1. These propeller blades may be identified by, but not limited to, Serial Numbers (S/N's) 853445 and higher except for the S/N's listed in Table 1 of this SB. Propeller blades inspected in accordance with the original, Revision 1, Revision 2, or Revision 3 of Hamilton Standard SB No. 14RF-9-61-86, and which passed inspection, need not be ultrasonically shear wave inspected again. (2) Remove propeller blade for off-wing inspection, inspect, and if necessary, replace with a serviceable propeller blade, in accordance with the Accomplishment Instructions of Hamilton Standard ASB No. 14RF-9-61-A90, dated November 9, 1995, propeller blade shanks with propeller blade spars, P/N 782683-1. These propeller blades may be identified by, but not limited to, S/N's less than 853445, and propeller blades with S/N's greater than 853445 that are listed in Table 1 of this ASB. (c) Perform a one-time visual and fluorescent penetrant inspection of the propeller blade shank for mechanical damage by August 31, 1996, in accordance with the Accomplishment Instructions of Hamilton Standard ASB No. 14RF-9-61-A92, Revision 2, dated March 6, 1996, on all propeller blade shanks with S/N's before 885751. Propeller blades inspected in accordance with the original or Revision 1 of Hamilton Standard ASB No. 14RF-9-61-A92, and which passed inspection or were repaired, need not be inspected again. (1) Prior to further flight, remove from service propeller blades with mechanical [[Page 16620]] damage that exceed repair limits specified in that ASB, and replace with serviceable parts. (2) Prior to further flight, repair propeller blades with repairable damage in accordance with the procedures described in that ASB. (d) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Boston Aircraft Certification Office. The request should be forwarded through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Boston Aircraft Certification Office. Note: Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the Boston Aircraft Certification Office. (e) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the aircraft to a location where the requirements of this AD can be accomplished. (f) The actions required by this AD shall be performed in accordance with the following Hamilton Standard service documents: ------------------------------------------------------------------------ Document No. Page Revision Date ------------------------------------------------------------------------ SB No. 14RF-9-61-86............. 1-34 4 November 9, 1995. Total pages: 34. ASB No. 14RF-9-61-A90........... 1-39 Original November 9, 1995. Total pages: 39. ASB No. 14RF-9-61-A92........... 1-44 2 March 6, 1996. Total Pages: 44. ------------------------------------------------------------------------ This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Hamilton Standard, One Hamilton Road, Windsor Locks, CT 06096-1010; telephone (203) 654-6876. Copies may be inspected at the FAA, New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. (g) This amendment supersedes priority letter AD 95-24-09, issued November 16, 1995. (h) This amendment becomes effective on May 1, 1996. Issued in Burlington, Massachusetts, on April 1, 1996. Jay J. Pardee, Manager, Engine and Propeller Directorate, Aircraft Certification Service. [FR Doc. 96-8950 Filed 4-15-96; 8:45 am] BILLING CODE 4910-13-U