JOHANNESBURG - Several planes, including some belonging to SAA and Comair, have been grounded.
The Civil Aviation Authority found irregularities at maintenance and technical service provider, SAA Technical.
The CAA has grounded the planes due to non-compliance.
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As a result, affected aircraft may not be flown until the necessary corrective action has been carried out.
SA Flyer Magazine Editor Guy Leitch says this is a follow on from an incident report by the CAA about what was called a 'Mango-nosedive'.
"It is extraordinary that the Civil Aviation Authority has resorted to grounding the airlines, I believe to be the Boeing 737s of Comair, Kulula and SAA. One would have thought that they would have thought they would have solved these problems before having to ground the airlines."
Airline operator Comair is advising customers to check the status of flights online.
SAA has also recalled some of its aircraft and cancelled four domestic flights.
It says it has contingency plans in place.
Watch the full interview above for more on this story.