COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES GAF N22 and N24 Series Aeroplanes AD/GAF-N22/29 Horizontal Stabiliser - Weather Proofing 11/79 Applicability: All models N22, N22B and N24 referenced in SB No. NMD 55-7. Document: Nomad SB No. NMD-55-7. Compliance: As detailed in the requirement document. Background: It has been found that water can be ingested and stored in the horizontal stabiliser.