Airworthiness Directive · Amendment 39-19269 · Oxygen
The Boeing Company Airplanes
This AD applies to The Boeing Company Model 747-200B, 747-300, and 747-400 series airplanes, certificated in any category, as identified in Boeing Special Attention Service Bulletin 747-35-2134, dated November 22, 2017.
We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 747-200B, 747-300, and 747-400 series airplanes. This AD requires replacing certain low-pressure oxygen flex- hoses with new non-conductive low-pressure oxygen flex-hoses in the gaseous passenger oxygen system in airplanes equipped with therapeutic oxygen. This AD also requires a general visual inspection of the low- pressure passenger oxygen system to ensure there is minimum clearance of the oxygen system components from adjacent structure and systems. This AD was prompted by reports of low-pressure flex-hoses of the flightcrew oxygen system that burned through due to inadvertent electrical current from a short circuit. We are issuing this AD to address the unsafe condition on these products.
Except as required by paragraph (h) of this AD: At the applicable times specified in paragraph 1.E., “Compliance,” of Boeing Special Attention Service Bulletin 747-35-2134, dated November 22, 2017, do all applicable actions identified as “RC” (required for compliance) in, and in accordance with, the Accomplishment Instructions of Boeing Special Attention Service Bulletin 747-35-2134, dated November 22, 2017.
(1) For purposes of determining compliance with the requirements of this AD: Where Boeing Special Attention Service Bulletin 747-35-2134, dated November 22, 2017, uses the phrase “the original issue date of this service bulletin,” this AD requires using “the effective date of this AD.”
(2) Where Boeing Special Attention Service Bulletin 747-35-2134, dated November 22, 2017, specifies contacting Boeing, and specifies that action as RC: This AD requires repair using a method approved in accordance with the procedures specified in paragraph (j) of this AD.
(3) Where the Condition column of Table 3 in paragraph 1.E., “Compliance,” of Boeing Special Attention Service Bulletin 747-35-2134, dated November 22, 2017, specifies “all airplanes,” for this AD, the Condition column of Table 3 is “airplanes on which one or more hose assemblies were replaced or disconnected.”
