AD 2001-08-05 Airworthiness Directives; Bombardier Model DHC-7-100, -101, -102, and -103 Series Airplanes

Models named: DHC-7-100, -101, -102, -103 series. Read the applicability below — it usually turns on serial or part numbers too.

Model DHC-7-100, -101, -102, and -103 series airplanes, serial numbers 003 through 113 inclusive; certificated in any category. Note 1: This AD applies to each airplane 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 airplanes 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 (d) 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 the collapse of the main landing gear due to leaks of hydraulic oil from the main landing gear selector valve, accomplish the following: Inspection (a) Within 100 flight cycles after the effective date of this AD, perform a general visual inspection of both endcaps of the main landing gear selector valve for the presence of hydraulic oil, in accordance with the Accomplishment Instructions of Bombardier Alert Service Bulletin A7-32-103, dated September 3, 1999. If no hydraulic oil is detected on either endcap, repeat the inspection at intervals not to exceed 400 flight hours until the requirements of paragraph (c) of this AD are accomplished. Note 2: For the purposes of this AD, a general visual inspection is defined as: “A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or drop-light, and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.” Replacement or Modification (b) If any hydraulic oil is detected on either endcap: Prior to further flight, perform the actions specified in either paragraph (b)(1) or (b)(2) of this AD. (1) Replace the existing aluminum endcaps (on the selector valve), part number (P/N) 34629, with new stainless steel endcaps having P/N 52982, in accordance with the Accomplishment Instructions of Bombardier Alert Service Bulletin A7-32-103, dated September 3, 1999. For main landing gear selector valves having P/N 57420-5, replacement of the endcaps terminates the repetitive inspection requirements of this AD. (2) Replace the main landing gear selector valve with a valve having P/N 57420-5A, in accordance with the Accomplishment Instructions of Bombardier Alert Service Bulletin A7-32-103, dated September 3, 1999. Note 3: Use care when removing the endcaps, so that the internal components do not fall on the ground and get damaged. (c) Within 12 months after the effective date of this AD: Perform the actions specified in either paragraph (c)(1) or (c)(2) of this AD, in accordance with the Accomplishment Instructions of Bombardier Alert Service Bulletin A7-32-103, dated September 3, 1999. Accomplishment of either paragraph (c)(1) or (c)(2) terminates the repetitive inspection requirements of this AD. (1) If a main landing gear selector valve having P/N 57420-1 or 57420-3 is installed, remove it and replace it with a valve having P/N 57420-5A. (2) If a main landing gear selector valve having P/N 57420-5 is installed, remove it and replace it with a valve having P/N 57420-5A or modify the valve to the P/N 57420-5A configuration (Modification 7/2742). For main landing gear selector valves having P/N 57420-5, replacement of the endcaps, as specified in paragraph (b)(1) of this AD, terminates the repetitive inspection requirements of this AD. Alternative Methods 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, New York Aircraft Certification Office (ACO), FAA. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, New York ACO. Note 4: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the New York ACO. Special Flight Permits (e) Special flight permits may be issued in accordance with §§ 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished. Incorporation by Reference (f) The actions shall be done in accordance with Bombardier Alert Service Bulletin A7-32-103, dated September 3, 1999. 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 Bombardier, Inc., Bombardier Regional Aircraft Division, 123 Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, New York Aircraft Certification Office, 10 Fifth Street, Third Floor, Valley Stream, New York; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. Note 5: The subject of this AD is addressed in Canadian airworthiness directive CF-99-31, dated December 21, 1999. Effective Date (g) This amendment becomes effective on May 29, 2001. Issued in Renton, Washington, on April 12, 2001. Donald L. Riggin, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 01-9666 Filed 4-20-01; 8:45 am] BILLING CODE 4910-13-U