One thing should be borne in mind before reading further:
air travel is, in terms of distance travelled, the safest transport mode. But
on occasion there are mishaps, and very rarely fatal accidents. One such
happened on the approach to the main airport near the Nigerian city of Lagosyesterday, and all 153 on board the aircraft concerned perished in the crash
and subsequent fire.
The Dana Air MD-83 that crashed yesterday
So what happened? One reason that air travel has become so
much safer over the years is that, when any kind of accident occurs,
investigations are made, errors corrected and lessons learned by all concerned.
That investigation will happen in this case. But we can get an idea of the cause
relatively easily, because accidents on approach to airports generally conform
to a limited set of causes.
Lagos is often visited by severe weather, but on this
occasion there were no storms or unusually turbulent conditions. As there was a
severe fire after impact, there must also have been plenty of fuel on board the
aircraft, so fuel starvation is unlikely. It has been reported that the flight
deck told of engine malfunction, but for both units to cut out would be very
rare indeed.
The aircraft was an MD-83, described as a Boeing, but more
familiarly known as a product of predecessor company McDonnell Douglas. The
MD-8X product line is the successor to the long established DC-9, updated with
more modern (quieter) power units. The high tailplane shown in some photos is
characteristic of this type, which has its two engines mounted at the rear of
the fuselage.
The aircraft came down on its belly – it “pancaked” onto a block of flats. That is
more characteristic of the result of a stall condition. This would not have
been so difficult to achieve with an MD-83, particularly if there were a fall
in engine power. As was demonstrated not so long ago when a similar MD-82 of
Spanair crashed after take-off from Madrid’s Barajas airport, pilot error
resulting in stall is all too possible.
The Spanair pilots had run through their
checklist but failed to look to see that the flaps were set for take-off.
No warning sounded. The configuration of the aircraft was wrong when take-off was attempted, the plane
stalled, fell out of the sky and crashed. Failing to get the configuration
right on approach – not enough flap for the speed of the aircraft – would also
lead to a stall.
If the pilots were not familiar with flying the aircraft on
one engine, of flying the approach without the aid of the autopilot (which
would most likely have disconnected itself if an engine had lost power or
failed), they would have had little time to take the right decision, and once the thing had stalled, no chance of
recovery. That’s my call on this crash on what is known thus far.
I’ll post an update as soon as there is more information.
No comments:
Post a Comment