Summary
We propose to supersede Airworthiness Directive (AD) 2016-11- 20, which applies to certain B/E Aerospace protective breathing equipment (PBE) that is installed on airplanes. AD 2016-11-20 requires replacing part number (P/N) 119003-11 PBE units. Since we issued AD 2016-11-20, we received a report that PBE units, P/N 119003-21, within a certain serial number range are made with candle tube material determined to have a low yield strength and may be volatile upon use or disposal. This proposed AD would retain the actions required in AD 2016-11-20 and would require inspecting and replacing P/N 119003-11 and 119003-21 PBE units. We are proposing this AD to correct the unsafe condition on these products.