AD 2000-04-10 Airworthiness Directives; Hoffmann Propeller Co. HO27( ) and HO4/27 Series Propellers

Makes named: cessna, piper, bellanca, aeronca, socata, lycoming, continental, teledyne. Read the applicability below — it usually turns on serial or part numbers too.

Hoffmann Propeller Co. HO27( ) and HO4/27 series propellers, with propeller mounting bolts, part number (P/N) FP20-147 ( ) ( ) ( ), installed. These propellers are installed on but not limited to Textron Lycoming O-360 series and O-540 series, and Teledyne Continental Motors O-470 series reciprocating engine powered airplanes manufactured by Aeronca, Bellanca, Cessna, DeHavilland, Piper, Socata, Rallye, Stinson, and Varga. Note 1: The parentheses that appear in the propeller models indicate the presence or absence of additional letter(s) which vary the basic propeller hub model designation. This airworthiness directive (AD) is applicable regardless of whether these letters are present or absent on the propeller hub model designation. Note 2: This 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 request approval for an alternative method of compliance in accordance with paragraph (b) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Required as indicated, unless accomplished previously. To prevent propeller mounting bolt failure, which could result in propeller separation and loss of control of the airplane, accomplish the following: Improved Propeller Mounting Bolts (a) Within 10 hours time-in-service (TIS), or 7 days after the effective date of this AD, whichever occurs first, remove from service propeller mounting bolts, P/N FP20-147 ( )( )( ), and install improved propeller mounting bolts, P/N FP20-147 ( )( )( )V. Make sure the new bolts have the “V” marking at the end of the P/N. Correct Torque (b) Torque all six propeller mounting bolts to 24.3 to 25.8 foot-pounds or 33 to 35 Newton-meters. Note 3: Further information on propeller mounting bolt installation and torquing procedures can be found in Hoffmann Propeller Company Owner Manuals E0110.74 or 0207.71, and on the sticker on the propeller. Retorque After First Flight (c) After installation of new mounting bolts, operate the airplane for no more than 2 hours TIS, check torque and retorque, as required, to 24.3 to 25.8 foot-pounds or 33 to 35 Newton-meters. Alternative Method of Compliance (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. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Boston Aircraft Certification Office. Note 4: 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) This amendment becomes effective on March 9, 2000. Issued in Burlington, Massachusetts, on February 14, 2000. David A. Downey, Assistant Manager, Engine and Propeller Directorate, Aircraft Certification Service. [FR Doc. 00-4262 Filed 2-22-00; 8:45 am] BILLING CODE 4910-13-U