'I'm not sure, but it sounded as if someone was screaming, just for a brief moment, after the plane burst into flames," said an eyewitness to the plane crash near Wonderboom Airport yesterday.
JD Hoffman shrugged, admitting it was not a nice sound.
Pilot Hercel McLeod and his student, Francois Erasmus, died when their Beechcraft Baron 55 plane first hit a tree with its wing and then plunged into the Apies River.
Police spokesman Constable William Mahlaole said the plane took off from Wonderboom airport after 3pm.
"They screamed over the radio to the control tower that something was wrong with the plane, and then it crashed," said Mahlaole.
The plane plunged into the river on the premises of Thulani Fishing and Leisure Resort on the corner of Lavender Road and Linvelt Avenue.
Pieces of wreckage drifted near the burnt plane, of which only the tail remained intact.
Foam used by firefighters floated around the aircraft that lay just off a concrete slab in the river.
Emergency officials waded through the water, their trousers wet up to their knees.
Shortly afterwards, the pilot's wife arrived, clearly stunned.
While shocked and crying members of the Loutzavia flying school flocked around her, trauma counsellor Pastor Eric Nel arrived after he was called to support the grieving family.
Tshwane community safety spokesman Console Tleane said it appeared that the pilot tried to land in the stream, but the wing hit a tree branch and the plane crashed.
"The Civil Aviation Authority will investigate the accident.
"But it appears that the plane experienced problems. Divers from the SAPS and the Tshwane Fire Brigade removed the bodies," he said.
Tleane added that the accident was the first fatal accident linked to Wonderboom Airport since 2001, which was an excellent record, taking into account that last year it processed 000 take-offs and landings without problems.
Two eyewitnesses, who did not want to be named, said the plane fell from the sky like a "rock".
Johan Schoeman was working in his garden on the neighbouring plot when he heard the plane backfire twice.
"I looked up. Its belly was just clearing the tree tops. Then it seemed as if the engine exploded in mid-air. The plane went down, clouded in red dust. It was an ugly sight. It is the first time in the 26 years I have been living near the airport that something like this has happened," he said.
Another witness, who had just left his place of work at the nearby South African National Defence Force base at Wonderboom, stood to one side, barefoot. As he saw the plane go down, he ran to a nearby garage, grabbed a fire extinguisher, ran into the river and tried to douse the flames.
But it became too hot.
Hoffman recalled how he heard a "smack-like" sound and saw the aircraft turning towards the river. Then he saw smoke.
"I dashed there on my motorbike. The plane lay in the water, burning. It sounded as if there was a scream from inside, just once," he said.
Chris Louw of Netcare 911 said they received a call just after 3pm.
However, emergency personnel could not get close because of the the heat of the fire.
After the flames were extinguished, they could not immediately establish who the pilot was, as the body was badly burnt.
As family members huddled together, divers recovered the bodies. They lay on the opposite bank of the river in body bags, barely visible behind the scorched tail of the plane, waiting for the morgue van.