Sunday morning saw the tragic news that five people lost their lives in a plane crash on Sunday in Durbanville. Details on exactly what happened remain unclear but we’ll lay down some of the groundwork before moving onto the analysis.

The plane had departed from Namibia and was on course until going off the radar at around 6:50 AM Sunday morning. An emergency call came in to emergency services at around 7:50 AM and the helicopter arriving at 8:03 AM then found the wreckage. You can read that full account HERE, this video below also offering a good summary.

Now first up we’re going to have a look at the radar tracking the plane to see the exact flight pattern. Here’s that video…

Here’s IOL explaining what may have caused the plane to go into a holding pattern, a technique used by planes when they cannot land at their destination for whatever reason:

Air Traffic and Navigation Services (ATNS) reported a “minor technical glitch”, which resulted in a sequence of departures and arrivals at the airport being affected.

ATNS spokesperson Percy Morokane said once flight sequencing was affected, flight departures and arrivals were bound to be delayed.

Vermaak said the ER24 flight desk had been alerted that the plane was affected due to the glitch. “It is understood from the Airports Company SA (Acsa) that all aircraft approaching Cape Town International Airport at the time were placed in a holding pattern due to a technical fault with their radars.

“The E-Med Rescue 24 aircraft was also in the holding pattern at the time. We lost contact with the aircraft approximately 11km outside the airport,” Vermaak said.

Morokane could not confirm or deny on Sunday whether the plane was part of the holding pattern, and denied that the crash had anything to do with the sequence of departures and arrivals.

“As ATNS we are required to provide a report of what transpired, and that includes communication between the pilot and our (air traffic controller) on duty, and any other related information to such an authority,” Morokane said.

Through our own research on aviation forum AvCom, the general feeling among pilots chatting on the forum is that the holding pattern, combined with low visibility, COULD HAVE resulted in ‘spatial disorientation’ for the pilot.

One user, ‘Starship’, gave this analysis:

Now if I dissect Flight N77R (Cessna 441 V5-NRS) flightpath, this is how it went. It approaches, crossing over the N7 freeway near Morningstar airfield on track 163°at an altitude of 9,900 ft at 200 knots with vertical speed zero

Crossing over Contermanskloof Track 165°at 9,200 ft at 213 knots vertical speed now -512 fpm. In the vicinity of the Milnerton Oil Refinery storage tanks (Tygerberg Hills side) track is 172° altitude 7,200 ft speed 189 knots vertical speed -1664 fpm

Over Parow track changes slightly to 164° altitude is 6,200 ft speed 166 knots vertical speed changes from descent to climb at +256 fpm

Over Cape Town International track is 165° Height is still 6,200 ft speed increases slightly to 172 knots vertical speed reduces to +128 fpm

At the end of the runway a left turn is executed (heading 20°?), the aircraft proceeds approximately 4km and executes another left turn heading north now height 6,300 ft speed 179 knots vertical speed +896 fpm

The aircraft then proceeds back north directly overflying the Tygerberg Nature Reserve and the row of hills behind – as it crosses the Tygerberg Valley Road slightly east of the Contermanskloof Road the heading is 334°height is 2,800 ft speed is 155 knots vertical height is -384 fpm

Just beyond where the Vissershok Road joins the N7 a 180° turn is executed

The aircraft then proceeds south basically following the N7. Directly over the Potsdam Road bridge an abrupt left turn is executed now heading 127° altitude is 2,500 ft speed is 139 knots vertical height is -1,408 fpm. This puts the aircraft east of the Tygerberg Hills rather than the normal approach to the west.

The aircraft overflies the Atlas Business Park on the corner of Contermanskloof Road and Potsdam Road and heads for the hill (height 200m) on which the Durbanville Hills Wine Estate is situated.

Crossing over the higher hills beyond there is a slight change in heading from 127° to 150° altitude is 1,400 ft speed is 135 knots vertical speed -1152 fpm

The aircraft proceeds with another minor heading change to 154° altitude drops to 1,000 ft speed reduces to 133 knots and vertical speed increases to -2,432 fpm at which point it impacts with the northern slope of the 400m high Kanonberg.

Whilst some users on AvCom have suggested a possible fuel shortage adding to the stress of being in a holding pattern in low visibility and a patient on board, there has been no report of a mayday, which the pilot would have (should have) declared if there were fuel issues.

Let’s look at some pictures from the accident, also sourced from AvCom:

No doubt debate will rage on until we receive official confirmation of whatever reasoning the experts have agreed upon. Until such a point (and probably still after) the crash will remain shrouded in mystery.

[sources:news24,iol&avcom]

[imagesources:ctmag,avcom(justindereuck, gradell,reader,greatdane,starship,andyf1,romeoet)]