AD 99-16-11 Airworthiness Directives; Boeing Model 737-600, -700, and -800 Series Airplanes

Models named: 737-600, -700, -800 series. Read the applicability below — it usually turns on serial or part numbers too.

Model 737-600, -700, and -800 series airplanes; line numbers 1 through 110 inclusive, 112 through 183 inclusive, 185, 186, 188, 189, 191, 193, and 195; 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 (c) 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 detect and correct improper grounding of the squib circuit, which would prevent the engine fire extinguisher bottle from discharging when commanded and could result in inability to extinguish an engine fire, accomplish the following: [[Page 43058]] Test (a) Within 90 days after the effective date of this AD, perform a test of the squib circuit ground studs of the engine fire extinguisher bottles to measure the resistance, in accordance with Boeing Telex M-7200-99-01098, dated February 5, 1999. Repair/Replacement (b) If the resistance is greater than 0.5 milliohms, prior to further flight, repair in accordance with Boeing Telex M-7200-99- 01098, dated February 5, 1999; or replace the ground stud with a new ground stud, in accordance with either paragraph (b)(1) or (b)(2) of this AD. (1) Install a ground stud having Boeing part number BACS53B, in accordance with Boeing Telex M-7200-99-01098, dated February 5, 1999; or (2) Install a standard built-up ground stud (nut and bolt type), in accordance with Subject 20-20-00 of Boeing Document No. D6-54446, ``Standard Wiring Practices Manual.'' Alternative Methods of Compliance (c) 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, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO. Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO. Special Flight Permits (d) Special flight permits may be issued in accordance with Secs. 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 (e) Except as provided by paragraph (b)(2) of this AD, the actions shall be done in accordance with Boeing Telex M-7200-99- 01098, dated February 5, 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 Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. (f) This amendment becomes effective on August 24, 1999. Issued in Renton, Washington, on July 29, 1999. D.L. Riggin, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 99-20058 Filed 8-6-99; 8:45 am] BILLING CODE 4910-13-U