曝光台 注意防骗
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maintain their minimum safe altitude for that
sector and continued descending until one of
the captains, realising the imminence of disaster,
opened the throttles.
Both the captains on board had attained all
their vast experience on piston engined aircraft,
which might well have been of significance
in this case, for in a propeller-driven aircraft,
opening the throttles automatically
increases lift via propeller slip stream over the
wings, raises the nose and arrests descent,
whereas in a jet, opening the throttles without
substantially raising the nose, simply drives
the aircraft down faster.
IMPACT
However that might be, they hit the ground
with an impact which devastated the 'Lower
41', a compartment below the flight deck
housing electronic and avionics equipment
resulting in an instant and total electrical
power failure which, in turn, led to loss of all
electrically powered instruments, navigational
aids, lights and hydraulic selection.
The crew endeavoured to keep the aircraft
flying on the few limited panel instruments
left to their disposal discerned in the dark by
the use of torches that they all carried, and by
reference to the runway lights.
The flight engineer subsequently stated that
when directed to enter the 'Lower 41' by
means of a hatch in the flight deck floor to
assess the damage to his utter consternation,
that there was no need to shine his torch into
the darkened compartment because all that he
could see below were the lights of Nairobi!
There followed a truly remarkable display
of airmanship, for whichever captain was flying
(I never discovered which of them performed
the final phase), in the absence of the
nose wheels and unable to lower the main
gear, elected to put the machine down on the
grass alongside the runway. This he achieved
by nothing other than torchlight and his
superb skill and resourcefulness, with the
result that the only casualty was the aircraft
itself and, perhaps, the dignity of whichever
captain was responsible.
Although the aircraft was re-built, and flew
again for many years, the left-hand seat captain
who held ultimate responsibility never
again flew 707s and retired flying pistonengined
DC-7Bs. But the million dollar question
remained unanswered: How does an
experienced and highly capable crew comprising
not one, but two captains in addition to a
senior first officer, contrive to fly right
through their minimum sector safe height into
high ground which they all must have overflown
countless times previously, both by day
and at night?
ATHENS INCIDENT
This accident was followed, not two years
later at Athens, by an equally fortuitous stroke
of luck involving a similarly structured crew –
two captains, the more senior of whom was in
command, a senior first officer in the third
World Airnews, June 2005. 63
pilot’s seat and a flight engineer.
They were flying one of the original 'A’
model 707s powered by straight jet Pratt &
Whitney JT-4 engines, renowned for the awesome,
deafening blast they emitted at take-off
thrust. This led, incidentally, to the introduction
of controversial and potentially hazardous
noise abatement procedures at most international
airports, requiring that, on reaching in
the region of 1 500 feet agl, the engines be
throttled back to a power just sufficient to
maintain level flight at V2 speed plus 10 knots
until well clear of built-up areas.
Any pilot found to have exceeded a specified
number of decibels recorded at measuring
points along the departure route, would be
threatened with being banned from operating
from that particular airport! That, however, is
another story.
Initial take-off power was set on those JT-
4s on a gauge registering what was known as
PT7 (Pressure Total at station 7) which was
simply a pressure reading just aft of the turbine,
while the aircraft was static although
lined up on the runway. This power was then
monitored for a minute or so, allowing the
engine to “grow” or expand with the heat
causing tension in the control cables which
necessitated re-adjusting, the throttles in order
to maintain the required PT7.
The brakes were then released and the
engines further monitored during the take-off
roll on the exhaust gas temperatures gauges to
ensure that the turbines did not “overtemp”.
Before take-off, it fell to the flight engineer
to extract the required PT7 for every take-off
from tables which he would enter with ambient
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