[risks] Risks Digest 23.24

From: RISKS List Owner (risko@private)
Date: Wed Mar 03 2004 - 13:59:36 PST

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    RISKS-LIST: Risks-Forum Digest  Wednesday 3 March 2004  Volume 23 : Issue 24
    
       FORUM ON RISKS TO THE PUBLIC IN COMPUTERS AND RELATED SYSTEMS (comp.risks)
       ACM Committee on Computers and Public Policy, Peter G. Neumann, moderator
    
    ***** See last item for further information, disclaimers, caveats, etc. *****
    This issue is archived at http://www.risks.org as
      http://catless.ncl.ac.uk/Risks/23.24.html
    The current issue can be found at
      http://www.csl.sri.com/users/risko/risks.txt
    
      Contents:
    Risks of Leap Years and Dumb Digital Watches, quadrennial posting (Mark Brader)
    GAO's latest evaluation of DOD software development practice (James Paul)
    Trouble with Mars rover Spirit (Erling Kristiansen)
    RFID tags in new US notes explode when you try to microwave them
      (Michael Borek)
    State looks at false bills from AT&T (Peter Howe via Monty Solomon)
    California e-voting: did programmers even try it? (Joel Garry)
    Anti-Spam Solutions and Security, Neal Krawetz (Monty Solomon)
    Legal Mercedes driver jailed for 18 months (Stefan Lesser)
    Re: Stolen heart monitor (Dave Brunberg)
    Re: Buffer overflows and VMS (Stanley F. Quayle)
    Re: Buffer overflows and Burroughs/Unisys (Bill Hopkins)
    Re: A320 Incident (Peter B. Ladkin)
    Abridged info on RISKS (comp.risks)
    
    ----------------------------------------------------------------------
    
    Date: Tue,  2 Mar 2004 19:33:50 -0500 (EST)
    From: msb@private (Mark Brader)
    Subject: Risks of Leap Years and Dumb Digital Watches, quadrennial posting
    
    All right now, how many people reading this...
    
    -> saw a previous version of this message in RISKS-6.34, 13.21, 17.81,
       and/or 20.83;
    
    -> have watches that need to be set back a day because, unlike the
       smarter kind of digital watch, they went directly from February 28
       to March 1;
    
    -> and *hadn't realized it yet*?
    
      [Please answer to yourself, but not to RISKS.  We don't really need a
      hand count.  PGN]
    
    ------------------------------
    
    Date: Tue, 2 Mar 2004 14:17:46 -0500 
    From: "Paul, James" <James.Paul@private>
    Subject: GAO's latest evaluation of DOD software development practice
    
    The General Accounting Office (GAO) today released the following report:
    
      Defense Acquisitions: Stronger Management Practices Are Needed to Improve
      DOD's Software-Intensive Weapon Acquisitions.  GAO-04-393, 1 Mar 2004
      http://www.gao.gov/cgi-bin/getrpt?GAO-04-393
    
    Quoting from Highlights of GAO-04-393:
    
    "Software developers and acquirers at firms that GAO visited use three
    fundamental management strategies to ensure the delivery of high-quality
    products on time and within budget: working in an evolutionary environment,
    following disciplined development processes, and collecting and analyzing
    meaningful metrics to measure progress.  When these strategies are used
    together, leading firms are better equipped to improve their software
    development processes on a continuous basis.  An evolutionary approach sets
    up a more manageable environment - one in which expectations are realistic
    and developers are permitted to make incremental improvements.  The customer
    benefits because the initial product is available sooner and at a lower,
    more predictable cost.  This avoids the pressure to incorporate all the
    desired capabilities into a single product right away.  Within an
    evolutionary environment, there are four phases that are common to software
    development: setting requirements, establishing a stable design, writing
    code, and testing.  At the end of each of these phases, developers must
    demonstrate that they have acquired the right knowledge before proceeding to
    the next development phase.  To provide evidence that the right knowledge
    was captured, leading developers emphasize the use of meaningful metrics,
    which helps developers, managers, and acquirers to measure progress.  These
    metrics focus on cost, schedule, the size of a project, performance
    requirements, testing, defects, and quality.  "In a review of five DOD
    programs, GAO found that outcomes were mixed for software-intensive
    acquisitions.  The F/A-18 C/D, a fighter and attack aircraft, and the
    Tactical Tomahawk missile had fewer additional cost and schedule delays.
    For these programs, developers used an evolutionary approach, disciplined
    processes, and meaningful metrics.  In contrast, the following programs,
    which did not follow these management strategies, experienced schedule
    delays and cost growth: F/A-22, an air dominance aircraft; Space-Based
    Infrared System, a missile-detection satellite system; and Comanche, a
    multimission helicopter...."
    
    Why GAO Did This Study
    
    	"The Department of Defense (DOD) has been relying increasingly on
    computer software to introduce or enhance performance capabilities of major
    weapon systems.  To ensure successful outcomes, software acquisition
    requires disciplined processes and
    practices.  Without such discipline, weapon programs encounter difficulty in
    meeting cost and schedule targets.  For example, in fiscal year 2003, DOD
    might have spent as much as $8 billion to rework software because of
    quality-related issues.
    	"GAO was asked to identify the practices used by leading companies
    to acquire software and to analyze the causes of poor outcomes of selected
    DOD programs.  GAO also was asked to evaluate DOD's efforts to develop
    programs for improving software acquisition processes and to assess how
    those efforts compare with leading companies' practices."
    
    What GAO Recommends
    
    "GAO recommends that the Secretary of Defense direct the military services
    and agencies to adopt specific controls to improve software acquisition
    outcomes.  These practices should be incorporated into DOD policy, software
    process improvement plans, and development contracts.  DOD concurred with
    two revised recommendations and partially concurred with two others."
    
    ------------------------------
    
    Date: Tue, 2 Mar 2004 13:55:38 +0100
    From: Erling.Kristiansen@private
    Subject: Trouble with Mars rover Spirit
    
    A good explanation of what happened to Spirit is at
      http://www.eetimes.com/sys/news/OEG20040220S0046
    
    In brief:
    - A software upload took place in order to correct some problem
    - A utility to delete files belonging to the old software was uploaded, but
    the upload failed
    - This failure was apparently forgotten or ignored, resulting in less file
    space being available for experiment data than anticipated
    - When the file system overflowed, a reboot occurred. This, apparently, was
    the intended behaviour
    - The reboot could not complete due to insufficient available file space
    - An infinite loop of reboots was entered
    
    RISKS, as I perceive them:
    - Relying on mission planners, working on assumed rather than actual file
    space, to not overflow file system
    - A file system that does not fail gracefully when overflowed
    - A boot sequence that requires resources that may become unavailable
    
    ------------------------------
    
    Date: Tue, 02 Mar 2004 09:54:25 -0500
    From: mikkeles@private (Michael Borek)
    Subject: RFID tags in new US notes explode when you try to microwave them
    
    "Prison Planet" (http://www.prisonplanet.com/022904rfidtagsexplode.html) is
    carrying a story of an experiment on microwaving the new US $20.00 bills
    which contain RFIDs.  (The site includes pictures of the results.)
    
    Apparently, the new bills were setting off every RFID monitor they passed
    through!  Wrapping the bills in aluminium foil stopped this behaviour, but
    they decided to try microwaving the bills.  This led to the RFIDs exploding
    and burning the face of Andrew Jackson's picture.
    
    This could become quite common a problem as word passes that microwaving can
    destroy RFIDs without the proviso that this may (will) damage the goods.
    
    (A discussion is also being carried on Slashdot:
    http://slashdot.org/article.pl?sid=04/03/02/0535225&mode=nested)
    
    ------------------------------
    
    Date: Tue, 2 Mar 2004 12:24:52 -0500
    From: Monty Solomon <monty@private>
    Subject: State looks at false bills from AT&T
    
    Company denies telemarket scheme, Peter J. Howe, *The Boston Globe* 2 Mar 2004
    
    Massachusetts utility regulators said yesterday that they are investigating
    a pattern of AT&T Corp. allegedly sending bogus bills to people who are not
    customers of the company, then trying to sell them AT&T phone service when
    they call to complain.
    
    After similar concerns emerged in upstate New York last week, the
    Massachusetts Department of Telecommunications and Energy said yesterday it
    has received more than 30 complaints since January from Bay State residents
    who said they got bills from AT&T although they have never had AT&T service
    or canceled it months or years earlier.  ...
    
    http://www.boston.com/business/globe/articles/2004/03/02/state_looks_at_false_bills_from_att/
    
    ------------------------------
    
    Date: Tue, 2 Mar 2004 10:36:32 -0800
    From: "Joel Garry" <JoelG@private>
    Subject: California e-voting: did programmers even try it?
    
    I think I electronically voted at a polling place in the California Primary
    today.  California has an odd primary rule where, if you register
    non-partisan, you are allowed to put bad data into the party of your choice,
    if they have chosen to let non-partisans do so.  So I decided on a
    particular party, inserted the card, chose "large print," and was presented
    with page 1 of 8, a blank screen.  It seems the program dynamically assigns
    the various items to the pages, which evaluates to 4 pages with normal type,
    and 7 for large type.  So for large type it doubles the number of regular
    type pages and presents the blank page first.  Poll workers did not seem to
    understand this, and the help line for them to call was continually busy.
    
      [This RISK intentionally left blank.  JG]
    
    ------------------------------
    
    Date: Tue, 2 Mar 2004 00:47:23 -0500
    From: Monty Solomon <monty@private>
    Subject: Anti-Spam Solutions and Security, Neal Krawetz
    
    Dr. Neal Krawetz, Anti-Spam Solutions and Security
    SecurityFocus, last updated 26 Feb 2004, 
    http://www.securityfocus.com/infocus/1763
    
    In a recent survey, 93% of respondents reported dissatisfaction with the
    large volume of unsolicited e-mail (spam) they receive.  The problem has
    grown to the point where nearly 50% of the world's e-mail is spam, yet only
    a few hundred groups are responsible.  Many anti-spam solutions have been
    proposed and a few have been implemented. Unfortunately, these solutions do
    not prevent spam as much as they interfere with every-day e-mail
    communications.
    
    The problems posed by spam have grown from simple annoyances to significant
    security issues. The deluge of spam costs up to an estimated $20 billion
    each year in lost productivity -- according to the same document, spam
    within a company can cost between $600 and $1,000 per year for every user.
    
    ------------------------------
    
    Date: Tue, 2 Mar 2004 12:40:57 +0100 (W. Europe Standard Time)
    From: Stefan Lesser <stefan.lesser@private>
    Subject: Legal Mercedes driver jailed for 18 months
    
    Re: Solving e-mail problems economically (RISKS-23.22)
    
    > The [...] virus writers are no more responsible for the amounts of junk
    > [...] than I am responsible for the damage caused by an automobile whose
    > driver does not observe my bicycle until the last second and manoeuvres
    > suddenly.
    
    In recent German jurisdiction, exactly that happened.
    
    The driver of a Mercedes Coupe was jailed for 18 months after the death of a
    woman and her 2-year-old daughter. Apparently the mother, who was driving on
    the leftmost lane of a 3-lane Autobahn, was frightened by the fast approach
    of the Coupe and swerved right across all three lanes into a tree. The cars
    didn't even touch each other.  Although at the time of the accident the
    Mercedes was going at nearly 155mph, there was nothing illegal about that as
    there are no "global" speed limits on the German Autobahnen.
    
    Apart from the somewhat irritating court decision, which is open for
    retrial, there now seems to be the actual RISK of being prosecuted for the
    mis-reactions of others...  [Also, death threats against the judge!  PGN]
    
    English URL: http://www.timesonline.co.uk/article/0,,588-1006376,00.html
    German  URL: http://www.stuttgarter-nachrichten.de/stn/page/detail.php/600908
    
    Stefan Lesser, Support Center Muenchen, Burda Digital Systems GmbH, 
    Am Kestendamm 2, 77652 Offenburg  http://www.burdadigital.de  +49/89/9250-3433
    
      [Interesting case.  Check out the details.  PGN]
    
    ------------------------------
    
    Date: Tue, 2 Mar 2004 08:56:50 -0500
    From: "Dave Brunberg" <DBrunber@private>
    Subject: Re: Stolen heart monitor
    
    >>The idea of an implantable medical device apparently requiring physical
    >>reconfiguration (at least) to talk to an external monitor implies a level of
    >>trust in the reliability of the external device which is seriously scary.
    >>The RISKS hardly need pointing out here...
    
    I think the RISKS of allowing unauthenticated remote reprogrammability of an
    implanted medical device may be just as scary.  One way of reducing that
    RISK may be to have some sort of an "emergency broadcast" safe mode in which
    a new external monitor could identify itself to the implant and authorize
    through a highly secure key which would require knowledge of a passphrase to
    transmit.  Of course, you'd really have to remember to change the default
    password....
    
    David W. Brunberg, Engineering Supervisor, The F.B. Leopold Company, Inc.
    
    ------------------------------
    
    Date: Tue, 02 Mar 2004 09:55:28 -0500
    From: "Stanley F. Quayle" <stan@private>
    Subject: Re: Buffer overflows and VMS (Levine, RISKS-23.22)
    
    > IIRC the late VAX/VMS systems also had built in buffer overflow prevention
    > features, probably a lesson learned from Multics.
    
    In fact, all systems running OpenVMS (formerly known as VAX/VMS) do.  Memory
    protection was built into the design of both the VAX and Alpha processors.
    The Itanium version of OpenVMS uses the processor's built-in in memory
    protection, as well.
    
    Pages can be set to be most any combination of read, write, or execute, with
    different protections depending on operating mode: user, supervisor,
    executive, or kernel.
    
    C programmers moving to OpenVMS quickly discover what the ACCVIO error
    message means.
    
    Stanley F. Quayle, P.E. N8SQ  +1 614-868-1363  Fax: +1 614 868-1671
    8572 North Spring Ct. NW, Pickerington, OH  43147
    
    ------------------------------
    
    Date: Tue, 2 Mar 2004 12:02:47 -0500
    From: "Bill Hopkins" <whopkins@private>
    Subject: Re: Buffer overflows and Burroughs/Unisys (Gobeski, RISKS-23.22)
    
    Keith Gobeski's note on the Burroughs stack architecture's improvements over
    many of its successors (compliment stolen from Wirth, IIRC) reminds me of
    the discussions in the late '70s of whether and how it could support the
    hot, new C language.  Eventually it could, mostly, but it was ugly.
    
    The key to a language-oriented architecture is preserving the language's
    abstractions (in this case the data array abstraction) in the run-time
    environment.  The Algol abstraction is clean: an array and an index combine
    properly if the index is within the declared range; otherwise it is illegal.
    An array row descriptor identified the memory segment and the limit, so an
    out-of-range access caused an exception.  There was no other way for a
    program to get at the memory, so it was inherently safe.
    
    Since C's memory abstraction is basically the hardware address, and
    addresses can be manipulated arbitrarily, any reasonably complete C
    implementation had to abandon tagged segments as array rows, instead putting
    all arrays in a single segment, keeping an allocation map in a
    locally-managed stack, etc. in order to generate an index for a memory
    access.  All the (parallel, fast) hardware assist for arrays was lost,
    replaced by (sequential, slower) software Some of the pathological C
    constructions were still impossible, of course; you couldn't force it to
    execute data.  As Unix (itself a reaction to Multics OS complexity) became
    trendy, who knew this was a Good Thing?
    
    The rise of the processor chip (and byte-oriented memory, and college
    courses in C) put an end to the experiments outside Burroughs/Unisys, as
    chip areas forced simple architectures (some actually *called* RISCs)
    without support for elegant and useful abstractions.  Heck, software can
    always make up for hardware deficiencies, right?
    
    (A 1982 ACM Computer Architecture News paper, "The Architecture of the
    Burroughs B5000 --20 Years Later and Still Ahead of the Times?" by Alastair
    J. W. Mayer, is still relevant another 20 years later.  It's on his web site
    at http://www.ajwm.net/amayer/papers/B5000.html)
    
    ------------------------------
    
    Date: Tue, 02 Mar 2004 11:41:42 +0100
    From: "Peter B. Ladkin" <ladkin@private-bielefeld.de>
    Subject: Re: A320 Incident (Ladkin, RISKS-21.48, June 2001)
    
    In RISKS-21.48, 21 June 2001, I reported on an incident to a Lufthansa
    A320. The A320 is a "fly-by-wire" aircraft, in that primary control is
    effected through computers and electrics rather than mechanical means.
    
    The captain's (CAP) sidestick controller was miswired during maintenance so
    that a "bank right" command initiated a "bank left" control signal and vice
    versa. This was discovered on take-off, when the captain corrected a left
    wing dip due to turbulent air flow with right sidestick movement ("bank
    right") and the aircraft's left wing dipped further, reportedly coming
    within two meters of touching the ground. The copilot took priority control
    (a feature of the electronic control architecture) and recovered the
    aircraft. The crew flew up a few thousand feet altitude, familiarised
    themselves with the problem as best they could, and returned to land the
    aircraft.
    
    It turned out that two wires connecting the CAP's sidestick to one Elevator
    and Aileron Computer (ELAC), of which there are two, had been
    reverse-connected during maintenance, and the fault had been discovered
    neither by post-maintenance check, nor by post-maintenance cross-check, nor
    by the flight crew's pre-take-off control system check.
    
    I had suggested in my Risks 21.48 note that I was puzzled by the partial
    reports of the incident then available. The final report was published as
    report 5X004-0/01 in April 2003 by the German Federal Bureau of Aircraft
    Accidents Investigation (german acronym BFU) and is available in English at
    http://www.bfu-web.de/berichte/01_5x004efr.pdf Thanks to John Sampson for
    bringing it to my attention.
    
    Salient facts are as follows. During previous flights, one of the two ELACs
    failed. Maintenance found a defect in the X-TALK-BUS between ELAC Nos 1 and
    2, found to be "caused by a bent connection pin (Pin 6K) in the plug segment
    AE of the socket for the ELAC no. 1." The attempt to replace just the pin
    failed and it was decided to replace the plug segment AE. There was no
    suitable spare plug AE for this series of airplane in stock, and the AE
    segments they had were not compatible with the remaining installed segments,
    so it was decided to replace all four plug segments AA, AB, AD, AE with a
    compatible set. This meant that "in a confined space approx. 420 assigned
    connector pins had to be reconnected."
    
    The method chosen was "ONE TO ONE", whereby "the wires were disconnected one
    after the other from the old plug and immediately connected to the new one."
    The mechanics used the wrong wiring diagram.
    
    How could this be? Well, an airplane and its equipment are identified by
    serial number (SN). The manufacturer knows what equipment was installed at
    build. Subsequently, the manufacturer issues Service Bulletins (SB) for
    modifications to installed equipment, and these SBs have different grades of
    urgency. Some are only "recommended", for example. So the installed
    equipment is identified by SN, and further by the log of which SBs have been
    accomplished. The applicable wiring diagram on p2 of the Airplane Wiring
    Manual (AWM) contained a designation that said it was applicable to
    airplanes with an "effectivity range" of 013-018 and those with effectivity
    001-012 on which SB 27-1030 had been accomplished. P4 of the AWM was
    applicable to those airplanes with effectivity range 001 to 034 on which
    SB27-1030 and SB27-1084 had been accomplished. SB27-1084 had been
    accomplished, but not SB27-1030, and the aircraft had effectivity 017.
    Hence p2 was applicable, but the mechanics thought p4 was applicable as
    SB27-1084 had been accomplished.
    
    Each numbered wire consists of a twisted red-blue pair. In segment AE, the
    "Monitor Channel" is connected by pair 0603. The Control Channel is
    connected by pair 0597. P2 specifies that these wires must be
    cross-connected (blue to red, red to blue) between the sidestick and ELAC
    plug. P4 specifies that these wires must be connected straight through (red
    to red, blue to blue).
    
    Furthermore, in the Aircraft Wiring List (AWL), the twisted pairs are always
    assigned in the order red, then blue, in the alphanumeric sequence of plug
    segment coordinates, except for these two wires. Wire 0603 is assigned blue
    then red to the pins 3C/3D, and wire 0597 blue then red to 15J/15K. Why? The
    manufacturer wanted to effect a uniform wiring for all its FBW airplanes,
    and from a certain type series on, the A320 wiring was planned to be
    identical to that of the A330 and A340. An interchange of colors was
    accepted for a certain transition period, and this aircraft belonged to the
    transition series.
    
    The BFU report points out that, had only the AE segment been exchanged, only
    the Monitor Channel would have been falsely connected, and with high
    probability an error message would have appeared on the cockpit aircraft
    monitoring display (ECAM). It doesn't say at which point this message would
    have appeared - at check, at cross-check (both performed only with the right
    sidestick), or at pre-take-off check (about which I speculate that maybe
    only the right side stick operation checked again - see last paragraph).
    
    The process of reconnecting 400-odd wires was a "major action on the control
    system", and the manufacturer Airbus requires in AMM 20-52-10 that a
    continuity check be performed on each individual wire, followed by an
    operational or functional test of the related function. This action was
    orally cancelled by maintenance supervisors upon inquiry by the mechanics,
    the reason being that the functional test to be performed after maintenance
    would reveal wiring errors. Well, it didn't.
    
    It was also required to perform a functional check and a control system
    check independently of each other. Well, they were performed simultaneously,
    and the check person "had not been informed sufficiently about the previous
    work flow", in particular that the reconnected wires had not been measured
    as required.
    
    Further, the control system test and functional test were performed only
    from the right sidestick, not from both, and a visual comparison check of
    the control surfaces was not performed. The report points out that the
    manufacturer's instruction in AMM-27-93-00-710-050 is ambiguous. It talks
    about how to perform the test with "the side stick". There are two. The
    mechanics told the investigators that it did not matter which sidestick was
    used to perform the tests, since "as both ELACs were connected to each
    other[,] possible faults of the one or the other ELAC would surely be
    indicated. This statement indicates lacking system knowledge of the
    mechanics."
    
    The cross-check staff member also used the same system documents to conduct
    his cross-check that were used by the staff member who conducted the first
    check. Regulations require a second set of documents to be used, to assure
    independence, which was thereby lost.
    
    The BFU points out that reconnecting all 400* wires of the ELAC plug "was
    connected to a high risk of errors." It also says that "a complicated and
    complex documentation system which tus is difficult to handle increases the
    risk of mistakes. The 173 procedural instructions valid for the area
    concerned contain many cross references making handling considerably more
    difficult. It was very time-consuming to find out which procedural
    instructions were relevant to the tasks to be performed."
    
    The BFU also points out that quality assurance and monitoring, including
    checks of the maintenance organisation by the LBA (the german regulator)
    were inadequate.
    
    After starting the engines, the AFTER START CHECKLIST for flight crew
    apparently only contained the instruction that the lateral flight controls
    were to be checked for full deflection, but not for the correct direction of
    deflection.
    
    The report illustrates the "causal chain" through the "Swiss Cheese Model"
    of James Reason. The "holes" that "line up" and allow the accident to happen
    are:
    1. "Quality assurance: insufficient support of the work flow,
       misinterpretation of regulations";
    2. "Documentation: complex, difficult-to-handle working documents;
       accomplished works was [sic] misdocumented";
    3. "Mistakes: inverted connection of 2 pairs of wires on ELAC plugs";
    4. "Test procedures: use of incorrect documentation wrongly accomplished
       tests; severity of action was not kept in mind";
    5. "Flight Operation: Checklist are [sic] insufficient; aileron deflection
       were [sic] not checked for correct deflection" leading to
       "Occurrence: "Serious Incident" Aircraft reacts inverted to the input 
       of the left sidestick at the time of the take off".
    
    These factors correspond roughly to the statement of causes and contributing
    factors.
    
    In my RISKS-21.48 note, I recounted my puzzlement engendered by the partial
    accounts then available, on the basis
    (a) hat the plugs were standardised, and that
    (b) a mistaken wire-up on ELAC 1 would have caused command signals
        in the reverse sense to those detected by ELAC 2 and the three Spoiler
        Elevator Computers (SEC), and I felt this should have been detected by
        the aircraft monitoring systems.
    
    Concerning (a), the report makes clear that the plug wiring was by no means
    standardised. The airplane belonged to a "transitional series" in which two
    wiring pairs were to be cross-connected, and the mechanics thought they
    should be connected straight-through, thanks to confusion over the
    appropriate wiring diagram.
    
    Concerning (b), the control signal discrepancy - ELAC 1 sensing a "bank
    left" command and and ELAC 2 and the three SECs sensing "bank right" - was
    not detected by the aircraft monitoring systems and displayed on the ECAM
    during test because the left sidestick was not tested. However, had CAP
    checked sidestick deflection during pre-take-off check, this discrepancy
    would surely have been triggered. Had only the first officer checked the
    lateral controls, the discrepancy would not have shown. The report says that
    "according to statements of the crew, this check was accomplished pursuant
    to the valid procedures." I wonder whether the "valid procedures" require
    both pilots to perform pre-take-off flight control checks?
    
    So the report leaves me still puzzled. If the CAP's sidestick had been moved
    in the direction of lateral control at any time before takeoff, then the two
    ELACs would have received contradictory sensor information, and ELAC No. 1
    would have received sensor information contradicting that received by the
    three SECs. I also suppose that both pilots should to perform pre-take-off
    control checks, since sidestick operation is independent. So we are either
    to suppose that a standard comparison across multiple channels is not
    performed by the control system architecture, or else that CAP did not
    perform a control check before departure and therefore either the
    pre-take-off checklist procedures omit an important requirement not noted by
    the BFU, or that the crew lied about performing the check according to
    procedures. It would have been more satisfactory had the report sorted these
    possibilities out.
    
    Peter B. Ladkin, University of Bielefeld, http://www.rvs.uni-bielefeld.de
    
    ------------------------------
    
    Date: 28 Jan 2004 (LAST-MODIFIED)
    From: RISKS-request@private
    Subject: Abridged info on RISKS (comp.risks)
    
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       INFO     [for unabridged version of RISKS information]
     There seems to be an occasional glitch in the confirmation process, in which
     case send mail to RISKS with a suitable SUBJECT and we'll do it manually.
       .UK users should contact <Lindsay.Marshall@private>.
    => SPAM challenge-responses will not be honored.  Instead, use an alternative
     address from which you NEVER send mail!
    => The INFO file (submissions, default disclaimers, archive sites,
     copyright policy, PRIVACY digests, etc.) is also obtainable from
       http://www.CSL.sri.com/risksinfo.html
     The full info file may appear now and then in future issues.  *** All
     contributors are assumed to have read the full info file for guidelines. ***
    => SUBMISSIONS: to risks@private with meaningful SUBJECT: line.
     *** NEW: Including the string "notsp" at the beginning or end of the subject
     *** line will be very helpful in separating real contributions from spam.
     *** This attention-string may change, so watch this space now and then.
    => ARCHIVES: ftp://ftp.sri.com/risks [subdirectory i for earlier volume i]
     http://www.risks.org redirects you to the Lindsay Marshall's Newcastle archive
     http://catless.ncl.ac.uk/Risks/VL.IS.html      [i.e., VoLume, ISsue]
       Lindsay has also added to the Newcastle catless site a palmtop version
       of the most recent RISKS issue and a WAP version that works for many but
       not all telephones: http://catless.ncl.ac.uk/w/r
     http://the.wiretapped.net/security/info/textfiles/risks-digest/ .
    ==> PGN's comprehensive historical Illustrative Risks summary of one liners:
        http://www.csl.sri.com/illustrative.html for browsing,
        http://www.csl.sri.com/illustrative.pdf or .ps for printing
    
    ------------------------------
    
    End of RISKS-FORUM Digest 23.24
    ************************
    



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