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.
100 SA Flyer
performance to climb above terrain before a
collision with the hard stuff.
This scenario is repeated with heart-
rending regularity in the accident reports.
Unfortunately, the refrain that the
pilot should not have got himself into
that predicament in the rst place has no
merit: A small change in wind speed or
direction can swiftly change visibility in the
mountains from unlimited to zero.
WHAT DOES THE LAW SAY?
ICAO’s standards and recommended
practices, which are applied by most of the
civilized world, dene VFR ight as being
where an aircraft is own in conditions of
visibility and distance from clouds equal
to or greater than those set out in a table.
The table covers various airspace types.
Basically, outside controlled airspace and
below 1,000 ft AGL or below 3,000 ft MSL,
the pilot must simply remain clear of cloud
and in sight of the surface.
Above 1,000 ft AGL or 3,000ft MSL,
the pilot must maintain a minimum vertical
distance (above or below) of 1,000 ft from
cloud and a minimum horizontal distance of
1,500 m. Visibility must be at least 5 km.
South African Civil Aviation Regulations
refer to the same table. However, an AIC
dated 01-09-15 says that from 1,500 ft AGL
to FL100 minimum horizontal distance from
cloud is 2,000 ft and vertical distance 500
ft. Our Regulations also add the proviso that
“Every VFR ight shall be conducted so that
the aircraft is own with visual reference
to the surface by day and to identiable
objects by night, and at no time above more
than three eighths of cloud within a radius
of ve nautical miles of such aircraft.”
This proviso probably hearkens back to
the days before ground- or satellite-based
navigational aids when the pilot was entirely
dependent upon his compass and visual
reference to the ground for navigation.
Although I am a bit of a Luddite when it
comes to placing too much reliance upon
GPS for VFR navigation, even the most
primitive aircraft today is likely to have
at least hand-held electronic nav-aids
that were undreamed of just a couple of
decades ago.
Continual visual reference to the ground
for navigation purposes is therefore, in my
view, quaintly obsolete.
THE VFR ON/OVER THE TOP DEBATE
Every new pilot in SA experiences
a baptism of re on his rst long cross-
country ight between the inland and the
coast – particularly if the weather gets a bit
iffy an hour or two into the ight. Student
pilots only ever y shortish cross-country
ights in ne weather.
When the weather suddenly turns
nasty over the escarpment, maintaining
visual reference with the ground below the
cloud can be fatal. And if the pilot is caught
unawares, there is no turning back. He
and his passengers just become another
number in the unacceptably long list of
statistics.
Fortunately, the orographic clouds
which tend to predominate over the
escarpment are normally fairly thin
vertically and follow the terrain quite closely.
Table Mountain’s famous ‘tablecloth’ is an
excellent example of orographic cloud with
which most South Africans are familiar.
To y over the top of such a cloud layer
is no big deal – other than being illegal. The
pilot is not going to survive a forced landing
in those mountains anyway, cloud or no
cloud.
Of course, there are caveats. Flying
over several miles of cloud requires that the
pilot ensures his destination and alternates
are VMC and that he has sufcient fuel if
conditions require a change of plan. He also
needs to be certain that he is not ying into
convective weather or thunderstorms.
However, with assistance from ATC
services, as well as real-time satellite, radar
and airport weather data being available
on-board, today’s VFR pilot is well-placed
to make sensible go/no go decisions
regarding en-route weather changes.
Dare it be said that many, if not most
VFR pilots safely y in the clear sky over
the top of a benign overcast anyway,
despite the regulatory position?
REGULATIONS NEED TO BE UPDATED
Filing IFR would at least legalise taking
the much safer high road on top of the
overcast, rather than running the gauntlet of
horrors in the mountains and murk below.
AOPA-SA lauded SACAA’s initiative a
few years ago to revise the requirements
for instrument ratings which would make
them more accessible to private pilots. After
all, further training can only benet aviation
safety. The prospect of GNSS approaches
at smaller airports would also be a great
incentive for many pilots to take the step of
achieving an IF rating and equipping their
aircraft accordingly.
Alas, these initiatives have been
limping along very slowly. Additionally, the
development of instrument approaches at
smaller airports has been devastated by
SACAA’s bumbling removal of some 90
airports from the AIP and those airports’
consequent disappearance from GPS and
FMS databases.
However, a revision of the Visual Flight
Rules is not affected by these matters.
Instrument ratings have been shown to be
of little relevance in trying to address the
persistent death toll of the most common
VFR-into-IMC accidents.
AOPA-SA will therefore be studying
this subject further, as well as considering
regulations implemented elsewhere,
developing amended VFR regulations
and pursuing their promulgation and
implementation during the course of this
year.
The answer to this safety question
seems to be much the same as the answer
in the famous old Cremora advertisement:
It’s not inside the clouds and clutter, it’s on
top.
The refrain that the pilot
SHOULD NOT HAVE GOT
HIMSELF INTO THAT
PREDICAMENT in the rst
place has no merit.
j
