97-20-13: Stator Blades Inspection

97-20-13 EUROCOPTER DEUTSCHLAND: Amendment 39-10240. Docket No. 97-SW-46- AD. \n\n\tApplicability: Model EC135 P1 and T1 helicopters, certificated in any category. \n\n\tNOTE 1: This AD applies to each helicopter 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 helicopters 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 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 helicopter from the applicability of this AD. \n\n\tCompliance: Required as indicated, unless accomplished previously. \n\n\tTo prevent failure of the tail rotor and subsequent loss of control of the helicopter, accomplish the following: \n\n\t(a)\tBefore further flight, and thereafter before the first flight of each day, visually inspect all stator blades in the stator hub area for cracks (see Figure 1). Inspect the stator blades in the areas where they are riveted to the stator hub. Pay particular attention to the radius areas where the stator blade base attaches to the stator hub. \n\n\t\t(1)\tIf the inspection reveals a crack at the base of a stator blade, remove the paint from the area and perform a dye-penetrant inspection. \n\n\t\t(2)\tIf the inspection reveals 3 or less cracked stator blades and a total crack length per stator blade of less than 15mm, stop-drill each crack with a 2mm diameter drill. \n\n\t(b)\tWithin 400 hours time-in-service (TIS), and thereafter, at intervals not to exceed 400 hours TIS, remove the paint from all stator blades in the stator hub area and perform a dye-penetrant inspection for cracks. \n\n\t(c)\tIf the inspections reveal cracks on any stator blade with a total crack length of 15mm or longer, or if more than 3 stator blades are cracked, remove the affected stator blades and replace them with airworthy stator blades before further flight. The inspections required by this AD must continue to be performed on all stator blades including replacement stator blades. \n\n\tNOTE 2: Eurocopter Deutschland Alert Service Bulletin No. EC 135-53A-001, Revision 01, dated August 8, 1997, pertains to this AD. \n\n\t(d)\tAn 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, Rotorcraft Standards Staff, Rotorcraft Directorate, FAA. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who mayconcur or comment and then send it to the Manager, Rotorcraft Standards Staff. \n\n\tNOTE 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Rotorcraft Standards Staff. \n\n\t(e)\tSpecial flight permits will not be issued. \n\n\tNOTE 4: The subject of this AD is addressed in Luftfahrt-Bundesamt (Germany) AD 97-249, effective September 25, 1997. \n\n\t(f)\tThis amendment becomes effective on December 29, 1997, to all persons except those persons to whom it was made immediately effective by Priority Letter AD 97-20-13, issued September 25, 1997, which contained the requirements of this amendment.