98 SA Flyer
Eight years ago,
almost to the day,
I wrote a carefully
crafted proposal
to the then
Commissioner of Civil
Aviation, Captain
Colin Jordaan, and
handed it to him when
he came to give a talk
at the Krugersdorp
Flying Club.
I
T summarised the concern that
probably the biggest killer in South
African general aviation is the classic
VFR-into-IMC accident, where the
pilot loses ground or horizon reference
in poor visibility and shortly thereafter
collides with terrain. At that time, the
proposal was that regulations akin to the
British ‘IMC rating’ be adopted to provide
pilots with a survival tool when faced with
unexpected weather conditions.
Every year there is at least one fatal GA
accident due to continued ight from VFR
into IMC. It has been hotly debated by the
GA community, but in the intervening years
there has been little progress in taking
positive steps to reduce this tragic yet
ongoing phenomenon.
Paradoxically, this class of accident is
an equal-opportunity killer: its victims are
not just low-hour, inexperienced private
pilots. Commercial, instrument-rated and
highly experienced pilots make up a large
portion, if not the majority, of these high-
speed and invariably fatal Controlled Flight
Into Terrain (CFIT) accidents.
EXPERIENCE AND QUALIFICATIONS OF
LITTLE RELEVANCE
So, perhaps the proposed IMC rating
was not the answer. My proposal was
targeted at the private pilot who ies well
under 100 hours per year – a pilot for
whom it is just not worthwhile to obtain and
maintain currency of a full IF rating.
Signicantly, a few months after making
the proposal, one of the country’s worst GA
accidents occurred when a Britten-Norman
Islander on a VFR ight collided with
mountainous terrain near Barberton in IMC
conditions. Nine people died.
The pilot of the Islander, although
young and with fairly little ying experience,
was a commercial pilot with instrument and
instructor ratings.
Several other such accidents occurred
over the next three years, fortunately
with fewer fatalities. But in August 2011
the worst GA accident in South African
aviation history occurred. Two twin-engined
Albatrosses returning from an airshow and
air race in Tzaneen, ying in formation,
collided with a near-vertical mountainside in
conditions of poor visibility.
13 people lost their lives, including
children and several well-known aviation
personalities. The pilots of the two aircraft
were highly experienced, one a 4,200-
hour commercial pilot with instrument and
CHRIS MARTINUS, PRESIDENT AIRCRAFT OWNERS AND PILOTS ASSOCIATION – SOUTH AFRICA
IT’S NOT INSIDE,
It’s t
BELOW: ICAO VFR minima.
www.sayermag.com
instructor ratings, the other a test and safety
pilot with nearly 3,000 hours of experience.
A cursory look through the many other
tragedies that befall pilots on VFR GA
ights where they have fatal encounters
with IMC does not reveal any discernible
pattern. Holding instrument ratings or
having many hours of experience appears
to make no signicant difference, even
though it intuitively seems like there should
be some connection.
A CLOSER LOOK AT THE PROBLEM
VFR aviation in South Africa has a fairly
unique problem.
Essentially, the country’s topography
looks something like an upside-down
dinner plate. The central plateau is several
thousand feet above sea level, whereas the
edges of the plate, the coastal plains, are
narrow. The terrain rises steeply from the
coastline to a tall ridge that surrounds the
inland plateau.
Many long-distance cross-country
VFR ights are between inland and coastal
areas, and must therefore cross this
mountainous barrier.
The Drakensberg escarpment delivers
some interesting challenges to pilots of light
unpressurised aircraft. Under clear VMC
conditions, ying over the Berg is within the
capabilities of even the smallest and least-
equipped light aircraft, as the mountains are
not so high as to require the use of oxygen
or pressurisation to cross them by a good
margin.
A forced landing in those rugged
mountains is, however, a fearsome thought.
But in the unlikely event of an engine failure
or other emergencies, pilots can generally
plan to glide to the more hospitable
farmlands on either side of the mountains.
For these reasons, accidents in the
mountains in clear, still weather are quite
rare.
However, winds will cause orographic
lift over the mountains, which results in
adiabatic cooling of the air and consequent
cloud formation. These orographic clouds,
by their very nature, form close to the high
ground and usually envelop the higher
peaks entirely.
This delivers a quadruple whammy
for the pilot of a light aircraft crossing the
escarpment:
Firstly, rapid and unpredictable
weather changes occur which cannot
easily be forecast, as low clouds that cap
and enclose clear valleys form swiftly and
unexpectedly.
Secondly, mountain winds make low-
level ight extra challenging.
Thirdly, those precipitous mountains
make the prospect of a safe precautionary
landing impossible.
And fourthly, the pilot loses visual
horizon reference. All of the visible ground
slopes steeply and even the cloud base is
not level, since these clouds will tend to
follow terrain contours.
The hapless pilot who nds himself
quite suddenly trapped in a valley under
cloud in the Berg has just run out of options.
He has nowhere to land, probably no space
to turn around – and nowhere to go even if
he does execute a successful canyon turn
(which has to be learned). He is probably
also ghting nasty winds and rotors.
Worst of all, he is struggling to keep the
wings level because all his visual cues are
misleading – and ying down a canyon on
instruments is just not an option.
Even for a competent instrument rated
pilot, an escape by climbing through the
clag is fraught with the danger of meeting
the granite embedded within the cloud,
fractious winds and insufcient aircraft
CHRIS MARTINUS, PRESIDENT AIRCRAFT OWNERS AND PILOTS ASSOCIATION – SOUTH AFRICA
AOPA BRIEFING
Table Mountain's 'tablecloth' is a good example of
orographic cloud on SA's mountains. Flying VMC
on top is no big deal - other than being illegal.