CASA has extended the deadline for aircraft owners to complete the supplemental inspection document (SID) program for some Cessnas.
The original date for compliance of 31 December 2015 has been moved out three months to 31 March 2016 for Cessna 100 series used in charter and aerial work, and Cessna 200 series used in private operations.
CASA has not extended the 30 June 2016 deadline for private Cessna 100 series.
CASA says it extended the deadline because of a backlog of inspection work, particularly in remote areas where access to specialist engineers is restricted.
Cessna and the United States Federal Aviation Administration (FAA) developed the SIDs inspections because of concerns about potential corrosion and fatigue damage to principal structural elements of older aircraft.
The SIDs program, which complements existing scheduled maintenance, requires additional detailed inspections of a range of structural components including wing spars, attachment points, strut attachments as well as horizontal and vertical stabiliser attachment points.
About 3600 Cessna aircraft in Australia are covered by the SIDs program.