Document ID: chunk:federal_register_of_legislation:F2016L01941:body:0:p1
Version: federal_register_of_legislation:F2016L01941
Segment Type: other
Provision Reference: 
Character Range: 0–3094

AIRWORTHINESS DIRECTIVE
On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below repeals Airworthiness Directive (AD) AD/GAS/1 Amdt 11 and issues the following AD under subregulation 39.001 (1) of CASR 1998 and subsection 33 (3) of the Acts Interpretation Act 1901. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct an unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.

Compressed Gas Cylinders
AD/GAS/1 Amdt 12  Inspection, Test and Retirement  26/2016

Applicability:  Aircraft to which Part 42 of CASR 1998 applies which carry rechargeable compressed gas cylinders that are not fire extinguishers.

                This AD is not applicable if the aircraft's Approved Maintenance Program includes procedures for inspection, test and retirement of compressed gas cylinders, valves and regulators.
Requirement:       1. The compressed gas cylinders shall be emptied. Except as varied below, the gas cylinders must be hydrostatically tested and have their markings updated to conform with the applicable manufacturer's, Australian Standard (AS) or United States Department of Transportation (DOT) specification, as set out below:

                     (a) Cylinders with a working pressure of less than 1MPa are not required to be subject to hydrostatic testing.

                     (b) Cylinders manufactured in the USA which have an outside diameter of less than 51 mm and length less than 610 mm are not required to be subject to hydrostatic testing.

                     (c) The retest of aircraft compressed gas cylinders must include a visual internal and external inspection together with a test by interior hydrostatic pressure in a water jacket or other apparatus of suitable form for the determination of the expansion of the cylinder. Permanent volumetric expansion must not exceed 10% of total volumetric expansion at test pressure or a permanent increase in volume of more than 1/5000 of its original volume.

                     (d) Where a cylinder specification or applicable CGA Publication does not adequately define damage limits, 50% of the damage tolerances stated in AS2030 shall be applied.

                     (e) Cylinders manufactured in the USA marked 3HT must be inspected and tested in accordance with the USA Compressed Gas Association Publication C-8, as in force from time to time (Standards for Visual Inspection of Compressed Gas Cylinders (1972), 49 CFR §180.209 and 180.213(c) (2) refer).
                     (f) A hydrostatic proof test can be performed as an alternative to a hydrostatic stretch test, but only where permitted by a particular cylinder specification.

                   2. Inspect and test