Permanent Air Force NCOs may be posted to a Ground Defence Training Section (GDTS) at any major RAAF base in Australia or to certain training units within Air Force Training Group. GDTS staff undertake both a training role and provide specialist advice to unit commanders. Reserve NCOs may be posted to a SECFOR Squadron, or to an instructional post or Reserve Airbase Protection Flight within one of the RAAF's 'City' Squadrons (Nos. 13, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 & 31 SQNs). ADG Warrant Officers (WOFFs) may be posted to staff or policy positions within a higher headquarters.