Subject: [Fwd: Commentary on Swissair 111 causal factors related to CRM]
Date: Sat, 12 Sep 1998 19:16:06 +0800
These were my first thoughts on the accident to Swissair 111 as they relate to design philosophy, human factors development and crew resource management - particularly with regard to the validity of a two-man crew complement in the smoke-in-the-cockpit situation.
This accident may turn out to have been unavoidable from the aircrew
point of view because it would appear that the FAA/NTSB and others have
been keeping their fingers crossed about Kapton (and other deficient)
wiring looms and harnesses for quite some time.
However, in my long career in aviation I came to value the (now missing)
"third man" because of all the valid sentiments I've expressed in the
attachment.His absence may well have been a significant causal factor in
this accident. When "electric jets" are running reliably the systems
supervisor (aka Flt Eng) may only have a visual look-out and
overseer/monitoring task. But I believe that to be just as vital as his
paramount and critical responsibilities when things come as unglued as
they evidently did for the Swissair crew. It may happen rarely but it
does happen. The Third Man's ability to off-load the pilot and copilot
makes the quintessential difference between survival and tragedy. It
permits the "flying and cross-checking" pilots to get on with their
vital flight control duties whilst ensuring that timely and appropriate
action is taken on systems that are no longer "automated". In a way,
it's a quality assurance task.
The incongruity of mooting such technology as the MD-11 as being an
automated, self-supervising system is now only too evident - in light of
sr111's catastrophically debilitating electrical malfunction that
obviously and easily defeated the automation. We are still a long way
from reliable, robotic, unmonitored inputs to safe flight.
I hope you read my submission and that it is of some use.
Obviously some of the debates about fuel dumping are now invalid in the
Swissair context. However they are consequential as an example of
time-critical initiatives that can possibly be later overlooked in the
heat of the situation. For interest I'll also include a posting that I
took from the AVWEB site. I would venture that the individual who posted
it is still unsure about his own responsibilities and checklist tasks in
the smoke emergency.
He's obviously a line pilot on Boeings. He's obviously concerned that at
least "his" Boeing checklist is deficient on the subject of smoke in the cockpit.
Considering the smoke checklist itself, please note my argument that it
is almost universally being run as a reverse of what sound logic would
dictate. In other words, first up, pilots should be able to activate an
easily selectable (but minimal) configuration and then warily restore
the electrics and avionics (but only as required). In this way the
situation is hopefully nipped in the bud. If the authorities are not to
ground Kapton wired aircraft generally, it may be the only sensible
thing to do. Technically, it's not a massive task to wire the relevant
buses through a single non-essential buses' monitoring switch (which
may end up as having a second position of "Flight Essential") and a
third (gated) position of "OFF" (for just such a situation as sr111's).
posted 11-09-98 10:10 BST
I think most would agree, with a severe smoke in
cockpit situation, the crew is going to be flat out getting much done
re formal, from the book, checklist actions.
It has always been my belief that certain non-
recall actions should be memorized such as (B757-767) smoke in cockpit,
auto speed brake and unscheduled stab trim etc. How many times
in the sim (controlled conditions) have you been waiting and
waiting for the other crewmember to find something
in the checklist.
The dirty little Fokker I used to fly in the good
old days at least had something written down to give the crew an idea re
shedding power in an elec. smoke situation.
B757-767 checklist doesnt suggest much at all. Me
thinks it was written by the company lawyers. Of course it shouldnt happen .
My point is this. It would be nice if Mr. Boeing
could at least give some sort of suggestions regarding order of things to do.
Nine times out of ten the crew will be flat out
knowing the source of the elec. smell and smoke emanating from under the
panel. This being the case, all our checklist says to do is turn
off the utility buses. Now the checklist is complete and after a
suitable time, the smoke is still p***ing out. At this point the
seasoned aviator may turn off his gens and hope for the best. Smoke
still coming and the crew in desperation, (manual flight at this point)
think of the stby buses. Hopefully they select gens back on, as once
the stby is selected off they lose the sby AH. Getting busier ..
The above scenario, or something similar, is all
left up to the crew (maybe the crew have not looked at the elec. section
for a while) to come up with as the s**t is hitting the fan in a big way.
Sorry to be so long-winded. I just feel Boeing could
at least give us some direction regarding the above procedure. Maybe
Ill cc this to someone who cares in Seattle.
Some might say the above is basic stuff, but not
necessarily for all.
By the way, dont any of you (air)bus drivers
misconstrue this as Boeing bashing. Im very happy with the Boeing,
however, feel there is some room for improvement, especially concerning
On another point, anyone out there flying B757-767
have SOP during single engine acceleration in 3rd segment where the
CAB is left back at V2 and a/c accelerated away from the bug? Saw
this procedure used by a carrier in the
past and thought it rather different.
eye-opening isn't it?
Subject: Amended submission - Swissair Accident analysis
Date: Sun, 13 Sep 1998 15:34:01 +0800
To: Communications@bst-tsb.x400.gc.ca (Canadian Transportation Safety Board)
primary accident investigators
Please find an up-dated amended version of my original submission
docs attached in Word6 format).
In it I have introduced a discussion of the integral tail-plane tanks
and the possibility that a partially powered configuration might bring
about a loss of control due to an aft-moving Centre-of-Gravity as fuel
dumping progressed. Bearing in mind that there is a long moment arm
involved, I imagine that the designers recognised that the use of fuel
dump would require tail-to-mains transfer at an appropriate rate - both
to minimize trim drag and to ensure that a tail-heavy situation could
not develop. However if the pilots were shutting off busses it is perhaps
possible, at that point, that the dump pumps were all powered yet the
tail-to-mains transfer pumps were not and the C of G moved rapidly aft
causing a loss of control.
For what it's worth.
I urge you to read my submission because it just might cast some new
light on this perplexing accident.
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