Airworthiness Directive · Amendment 39-18248 · Oxygen
Bombardier, Inc. Airplanes
This AD applies to the airplanes, certificated in any category, identified in paragraphs (c)(1), (c)(2), and (c)(3) of this AD.
(1) Bombardier, Inc. Model CL-600-2C10 (Regional Jet Series 700, 701, & 702) airplanes, serial numbers 10002 through 10336 inclusive.
(2) Bombardier, Inc. Model CL-600-2D15 (Regional Jet Series 705), and Model CL-600-2D24 (Regional Jet Series 900) airplanes, serial numbers 15001 through 15297 inclusive.
(3) Bombardier, Inc. Model CL-600-2E25 (Regional Jet Series 1000) airplanes, serial numbers 19001 through 19038 inclusive.
We are adopting a new airworthiness directive (AD) for certain Bombardier, Inc. Model CL-600-2C10 (Regional Jet Series 700, 701, & 702) airplanes, Model CL-600-2D15 (Regional Jet Series 705) airplanes, Model CL-600-2D24 (Regional Jet Series 900) airplanes, and Model CL- 600-2E25 (Regional Jet Series 1000) airplanes. This AD was prompted by results of a design review indicating that the burst pressure of the flexible hose, used to vent oxygen from the high-pressure relief valve of the oxygen cylinder overboard, was lower than the opening pressure of the high-pressure relief valve, which could cause the flexible hose to burst before it can vent the excess oxygen overboard. This AD requires replacing the oxygen hose assembly with a new, improved assembly. We are issuing this AD to prevent the accumulation of oxygen in an enclosed space, which could result in an uncontrolled oxygen-fed fire if an ignition source is nearby.
Within 5,800 flight hours or 44 months after the effective date of this AD, whichever occurs first: Replace all oxygen hose assemblies having part number (P/N) S6946-01 with new, improved assemblies having P/N BA670-44025-001, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin 670BA-35-013, Revision B, dated May 20, 2015, including Appendix A, dated May 21, 2013. For airplanes on which Supplemental Type Certificate ST01648NY (http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgstc.nsf/0/ebd1cec7b301293e86257cb30045557a/$FILE/ST01648NY.pdf) is installed, only PART B of the Accomplishment Instructions of Bombardier Service Bulletin 670BA-35-013, Revision B, dated May 20, 2015, including Appendix A, dated May 21, 2013, is required.
