The alert was sounded after the two aircraft, which had taken part in an airshow at Tzaneen, failed to arrive at the Rand Airport at Germiston on time.
Search parties on foot are scouring the areas where the aircraft may have gone down. The Wolkberg area near Tzaneen is one of the areas being searched as aircraft were reported in the area.
The two Albatross planes had been at the Tzaneen Air Show and left for Rand Airport before lunch on Sunday in marginal weather. There are believed to be between 12 and 14 people on board, including the pilots. It is believed that the aircraft would have flown in formation flying directly to Rand Airport.
Search and Rescue's Johnny Smit says that all the standard procedures were followed after the aircraft were reported missing. An air search was conducted on Sunday afternoon till poor light forced the aircraft to withdraw. Several of the pilots who had been at the show joined in the search.
A new air search will be launched at 05:00 on Monday morning, weather permitting.
In the meantime attempts are being made to triangulate the last known positions of cellphones which may have been on board, according to a post on iflyafrica.
It is reported the several prominent people in aviation circles were on board as well as the families of pilots taking part in the air show.
Sapa reports that the Mopani District Municipality believes the planes may be in the George's Valley area, between Polokwane and Tzaneen, spokesperson Mashadi Mathosa said.
"There is a joint search operation to find the planes...George's valley is a mountainous area so we are concerned."
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