> Mr. Bertrand Bonneau (the translator to English)

Actually, Mr. Mellor did the translation.
                               [Yes, that's what he said in RISKS-10.02.  PGN]

>For example, I was very surprised by the total absence of any reference
>to the B7[5]7/B767 with their glass cockpits and computers.

The B757/767 and A320 are two different generations of aircraft.  And nobody's
crashed a 757/767 yet.  The airplanes could certainly come in for criticism
(for the way Boeing's addressed the general man-machine problems of glass
cockpits), but the *critical* issue of the day is the A320.


Looks like it's time for some refresher background:

757, 767, and A310: introduced in '82 and '83: characterized by *conventional*
  flight controls, glass artificial horizons and nav displays (EFIS), and
  performance management systems (PMS).  These airplanes are referred to as
  "classical glass" by at least one magazine (Flight International).

  The 757 and 767 have identical cockpits.  They have conventional (analog
  dial) airspeed, altitude, vertical speed, and VOR/ADF indicators.  These
  surround the two glass EFIS CRT's to form the "classic T."  Engine monitoring
  is accomplished through an Engine Indication Control Advisory (EICAS) system,
  which is comprised of a primary flight instrumentation display (engine
  power, temperature, etc) and a secondary advisory display (checklists, hints,
  systems info, etc. pop up).  These are stacked on top of each other on the
  center console.  Boeing's operational cockpit philosophy, since the early
  1970's, has been "need to know."  The 757/767 represent the most extreme
  manifestation of this philosophy, by any manufacturer, to date.  The im-
  plementation has resulted in the *necessity* of pilots having to work around
  system obstacles, by pulling circuit breakers (one source claims that on a
  typical 767 flight, sixty CB's are set and reset).  Data from an
  (unpublished?) survey by Earl Wiener indicates that pilots are neatly
  divided in their opinions of the 757/767 cockpit.

  The A310 is similar, except it packs more info into the EFIS displays, and
  it has conventional dial engine instruments.  However, it also has two EICAS
  displays, to handle a multitude of system and advisory information.  Airbus's
  philosophy (on the A310) was "nice to know."  The cockpit is not, however,
  popular with pilots, because of a variety of environmental factors (too
  cold, for one).  There is a retrofit which gives the A300-600 more or less
  the A310's cockpit.  The A320 design leans more in the 757/767 direction.


Next generation: the A320 (introduced in 1988).
  The A320 did away with most dials (except for backup instrumentation)
  and combined airspeed and altitude information into the primary flight
  display.  These bracket (left and right, respectively) the artificial
  horizon display.  The display is quite small (7.25") , and, in my opinion,
  poorly designed (this was recently discussed ad nauseum on RISKS and
  sci.aeronautics).  The nav display (beneath it) is more or less a typical
  nav display.  Nothing revolutionary there.

  The flight controls on the A320 are non-standard.  The aircraft is controlled
  through sidesticks, which map pilot commands into aircraft action.  There
  are a multitude of control modes available (for instance, "direct" mode, in
  which the sidestick deflections map to surface deflections), "autopilot" (in
  which the sidestick controls the autopilot), "C*" (which provides an
  unconventional method of flight guidance), etc.  There are also many
  "protections" built into the various modes, such as automatic engine spool-
  up if the angle of attack gets too high (alpha floor--but it doesn't work
  under 100' radio altitude, hence the Habsheim crash), preventing excessive
  bank or pitch, etc.  The two sidesticks do not provide "active" artificial
  feel (although they do have a spring to prevent excessive deflection), and
  are not interconnected.

  There are manual backups to the flight control system, but they're not
  intended for normal use.  The "manual" backups amount to electric trim, a
  manual rudder, and, according to at least one source, a manually settable
  horizontal stabilizer.  At least one source has claimed that Airbus isn't
  advocating training for the "manual" flight mode, despite it being the
  only way that a test flight (which Bev Littlewood recently mentioned) could
  have been landed.

Latest generation: MD-11/747-400.
  The MD-11 (1990) and 747-400 (1989) feature six large color CRT displays,
  and provide data in a manner similar to that of the A320 and 757/767.
  The MD-11 features a "fly-by-wire" system (without any changes in control
  laws and no protections), with a fully "manual" hydraulic backup.  The
  747-400 features a standard hydraulic-based control system.  Both airplanes
  are two-man ships, though, and include significantly reworked electrical and
  systems design.

  Note, though, that both Boeing and McDonnell-Douglas have opted for
  *conventional* flight laws.  Boeing is reportedly continuing the trend
  with the 767-X (777), which, if launched, will have fiber-optic "fly-by-
  light" systems.

In essence, these airplanes share (a) similar nav displays, (b) similar
PMS/FMCS systems, (c) similar (unknown) problems relating to the consequences
of using digital electronics for flight-critical systems (these range from
static problems to temperature to solar radiation), (d) the unknown effects of
"hiding" a lot of information in two little CRT's, and (e) a propensity to
encourage "heads-down" behavior.  Only the A320, however, has a fly-by-wire
system with "unconventional" control laws, and only the A320 has been sold
on the basis of preventing the pilot from making fatal errors.

As you note, though,

>The main point of this article is that the procedures were bad,

which brings us back to ERGONOMICS.  The point of the article was to draw
attention to the questionable workmanship of the aircraft, and the poor
man-machine interface.  In my opinion, the A320 is the real loser in the
crop of digital airplanes, with the 747-400/MD-11 coming a distant second (for
the idiotic decision to introduce long-range aircraft with only two pilots).

>the French FAA was conducting the investigation rather than the French
>Department of Justice.

Actually, both the DGCA and a local magistrate were conducting an
investigation.  The DGCA has released its report, which white-washed the
aircraft and systems.  The magistrate's report is still to be released (?).


>Even if the French judges are only ten times
>technically-smarter than ours and if the French-FAA is only ten times
>more corrupted than ours, I'd still rather see their FAA, not their DoJ
>conduct the investigation.

But there's an explicit conflict of interest there: Airbus Industrie is
essentially a public-works project for the aerospace sector in Europe.  It
is HEAVILY financed by the French government, and is a major employer in
France.  French prestige is on the line, and we all know how "weird" the
French government can get, when protecting its interests (remember
the Rainbow Warrior? :-)).  The behavior of both the French government after
Habsheim, and Airbus Industrie after Bangalore, are certainly bases for
skepticism.


>Well, in the US the NTSB (and the FAA)
>typically have "probable cause" within a day, even though investigations
>take many months or even years.  Is it suspect, too?

There are numerous cases when the NTSB has not been able to issue a probable
cause, and numerous more where the probable cause has turned out to be in-
correct.  What the French government did, however, was state--in a definitive
manner--that the Habsheim crash was a result of pilot error.  The FORM their
statement took would certainly not be acceptable coming from the NTSB.  It
must be very awkward to have a supposedly objective government agency im-
mediately *defending* an airplane of which many hard questions can be asked.
It's my impression that what irked many people was this very sight of their
government playing the role of apologist.

To the best of my knowledge, the FAA does not issue probable-cause statements.
Its options are limited to emergency regulatory action, based upon preliminary
crash assessments from the NTSB (cf. the AAL DC-10 at O'Hare).  It, too,
has been known to reverse its decisions.


>To sum it up: opinionated reporting may leave something to be desired.

The style of the article was somewhat clumsy, but it has a number of good
points.  It is not appropriate to discount it sorely because of its
feeble attempts at rhetoric.  A number of people seem to have been thrown
off by the assumption that it represents the epitome of the debate in France.
It doesn't, as Pete Mellor has noted.  But it certainly contains enough
(apocryphal) anecdotes to stimulate serious discussion.

Robert Dorsett                                       Moderator,
Internet: rdd@rascal.ics.utexas.edu                  Aeronautics Digest
UUCP: ...cs.utexas.edu!rascal.ics.utexas.edu!rdd

Re: The A320's attacks of nerves (Cohen, RISKS-10.05)

In RISKS 10.05, Danny Cohen 

 Re: Article on A320 (Mellor, RISKS-10.02)
Karl Swartz 
4 Jun 90 02:21:46 PDT (Mon)
I don't have definitive answers, but I think I can clarify the terms
a bit.  "About-turn on the ground" is an abort before the beginning of
the takeoff roll, that is, a decision to return during the pre-takeoff
taxiing, whereas an "acceleration-stop" is an abort after the beginning
of the takeoff roll but before V1 (the velocity at which the plane is
committed to a takeoff) is attained.  The latter is an aborted takeoff;
beyond V1 the plane is committed to a takeoff though once airborne the
crew could immediately turn back and land.

As for the matter of "cabin altitude being on the increase", pressure
in the cabin is measured in terms of altitude rather than PSI or bars
or some other unit.  Typically, the cabin of a commercial aircraft is
pressurized to a pressure equal to that at an altitude of 8,000 feet
above mean sea level.  A failure of the pressurization system would
cause the pressure to decrease such that the effective cabin altitude
would increase from nominal, approaching the actual altitude of the
aircraft.  Often this occurs due to a rupture of the pressure cabin
and a consequent violent decompression, but in this case it appears
the decompression was gradual, presumably due to a failure of the
regulation systems.  No matter, the pilots still must descend to an
altitude at which the cabin altitude is within acceptable limits.

Karl Swartz, 1738 Deer Creek Ct., San Jose CA 95148  1-408/223-1308



 A320 - The Attacks Continue
Pete Mellor 
Thu, 7 Jun 90 20:33:41 PDT
In RISKS-10.05, Danny Cohen RISKS-10.05, Atkielski.TDS-ASF@SYSTEM-M.PHX.BULL.COM points out that
the actual magazine is "Science & Vie", and that the article was in the
"Aeronautique" section. Sorry, my fault. Serves me right for working from a
photocopy of only the relevant pages.

He also points out that:

> A rebuttal from Bernard Ziegler, technical director
> of Airbus Industrie, may be found in the following May issue.

My thanks for this information. Perhaps in the interests of balance, RISKS
should carry a translation of that, too. Are you offering, Bernard? Come on,
it's someone else's turn! :-)

My thanks also to Steven Philipson, Karl Swartz and Jordan Brown for answers
to my queries about the terms "acceleration-stop", etc. Since Karl copied his
reply to RISKS, I assume it will be appearing shortly.

Pete Mellor
(Author of the above, but mere translator of Bertrand Bonneau's article!)



 Re: Private mail on BBSes...(and the A320?)
Pete Mellor 
Thu, 7 Jun 90 20:53:21 PDT
With regard to David Gursky's points about BBS mail that deals with "illegal"
activities, what if Airbus Industrie decides the Bertrand Bonneau's article
is libellous. Do they sue the publishers of "Science & Vie", M. Bonneau, me,
Peter G. Neumann, or all of us?

OK, RISKS is a moderated forum, so I suppose the buck ought to stop with the
moderator. :-)

This problem reminds me, however, of the case of Goldsmith v. Pressdram
(publishers of the UK magazine "Private Eye") a few years ago. Sir James
Goldsmith sued Private Eye for libel. As part of his action, he also tried to
sue the distributors and retailers of the magazine. This was thrown out, since
if the precedent had been established, it would have meant that every newsagent
and magazine stall-holder in the land would be expected to read every
publication he sold from cover to cover, and be liable if he failed to
withhold any issue that was libellous.

Doesn't a similar common-sense principle apply to (non-moderated) BBS's?

Pete Mellor




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