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ACCESSION #: 9610220158

NOTE:     This text document was processed from a scanned
          version or an electronic submittal and has been
          processed as received.  Some tables, figures,
          strikeouts, redlines, and enclosures may not have
          been included with this submittal, or have been
          omitted due to ASCII text conversion limitations.  In
          order to view this document in its entirety, you may
          wish to use the NUDOCS microfiche in addition to the
          electronic text.

                         Information & Support Services
                         P.O.  Box 3707
                         Seattle, WA 98124-2207

October 11, 1996
G-1151-SJA-96-629

Document Control Desk
United States Nuclear Regulatory Commission
Washington, D.C.  20555

Reference:     a)   Boeing Letter G-1151-RSO-92-365 dated August 31,
                    1992; R. S. Orr to the NRC Operations Center

               b)   NRC Letter Docket No.  99901227 dated August 12,
                    1992; L. J. Norrholm to R. S. Orr; Subject: Response
                    to 10 CFR 21 Inquiry

Dear Sir or Madam:

In accordance with the reference correspondence and 10 CFR 21, Boeing is
sending the NRC the attached error notice(s) received from our former
software suppliers.  Because of unknown current addresses, the following
former customers were not notified:

     Reactor Controls, Inc.
     Echo Energy Consultants, Inc.
     Nuclear Applications and Systems Analysis Company (Japan)
     Nuclear Power Services
     Tenera Engineering Services
     Gibbs & Hill, Inc.
     Holtec International

Error notices have been sent to our other former customers.

Very truly yours,

Sandra J.  Andrews
Nuclear Administrator
Phone: (206) 865-6248
FAX: (206) 865-4851
Mail Stop: 7A-33, or
e-mail: Sandra.Andrews@PSS.Boeing.com

Enclosure(s):  ANSYS Class3 Error Reports 96-33, 96-34, 96-35, 96-36, 96-
               37 and 96-38.
               ANSYS QA Notice QA96-06
               ANSYS Class3 Error Reports 92-25R1, 93-03R1, 93-33R1, 94-
               68R2, 95-27R1, 95-39R1 and 95-49R1
               Revised Class3 Error Report Summary for Rev 5.1
               ANSYS Class3 Error Reports 96-39, 96-40 and 96-41
               ANSYS QA Notices QA96-07 and QA96-08
               Class3 Error Report Summary for Rev 5.2 and Release 5.3

                         ANSYS, Inc.
                         201 Johnson Road          Telephone 412.746.3304
                         Houston, PA 15342-1300    Facsimile 412.746.9494

                             August 12, 1996

Dear Class3 Error Recipient:

     Enclosed you will find ANSYS Class3 Error Reports 96-33, 96-34, 96-
35, 96-36, 96-37 and 96-38.

     Also enclosed is ANSYS QA Notice QA96-06 which has been issued to
clarify the program documentation on the operation of the KUSE command.
Some past Class3 errors incorrectly suggested that using KUSE,-1 was a
way to avoid the errors reported.  The reports affected by this have been
revised and are also enclosed as 92-25 R1, 93-03 R1, 93-33 R1, and 94-68
R2.

     Finally, attached are Class3 Error Reports 95-27 R1, 95-39 R1 and
95-49 R1.  These reports have been revised and reissued to update the
versions containing the errors and corrections.

     I have also attached a newly revised Class3 Error Summary Report for
Rev.  5.1.  An error appeared in the report dated 5/31/96.  Please
discard that copy and use the enclosed.

                                        Sincerely,

                                        ANSYS, Inc.

                                        William J.  Bryan
                                        Quality Assurance Manager

     ANSYS [Registered Trademark] is registered trademark of SAS IP

                  ANSYS Revision Identifier Description

     ANSYS revision identifiers consist of a major revision level, a
minor revision level, a correction level, and occasionally a special
version level.  An example of how this is constructed is shown below:

                                5.0A--10

          major revision level               special version identifier

          minor revision level               correction level

     Major revision level changes indicate that new features have been
added to the program and that some level of program architecture change
and/or file structure has occurred.  Minor revision level changes also
indicate that new features have been added to the program, but files are
upwardly compatible.  All known error fixes are included in both minor
and major revisions.  Changes to the correction level indicate that it is
primarily an error correction release.  Special version identifiers
indicate that one or more additional minor changes have been made to the
program, normally to circumvent an error.  Special versions are not
general releases to all ANSYS licensees, since they typically represent
errors occurring only on one system, a subset of our customers who have
specific graphics devices, etc.

     The ANSYS revision identifier(s) shown under "corrected in" on the
front side of this Class3 Error Report indicates the first possible
revision that could contain the correction.  A major program change
needed to fix an error can dictate that the next minor or major revision
will contain the fix rather than the next correction level.  For example,
when errors were being reported while Rev.  4.3A was the latest
production version, most Class3 error reports indicated that 4.313 was
the "corrected in" revision.  Others requiring significant code
restructuring were reported as fixed in 4.4. Rev. 4.3B was never
released, but Rev. 4.4 contained all error corrections noted as fixed in
4.3B.

     An identifier indicated under "corrected in" does not guarantee that
a general release of that revision of ANSYS will occur.  It does indicate
that the correction is known and implemented in the coding that would be
part of that general release.

                     Equivalent Product Identifiers

     The ANSYS family of component products occasionally undergoes name
changes between revisions and/or changes in the functionality of derived
products (such as ANSYS-PC/LINEAR).  To minimize the potential for
confusion in these areas, the important product name equivalences
(similar program functionality and error content) are listed below.

     ANSYS/ED  contains all errors shown for the full ANSYS product,
                                             starting at Rev.  5.0, and
                                             beyond, unless otherwise
                                             noted.

     PC/LINEAR is equivalent to              WS/LINEAR at Rev. 4.4A,
                                        and  ANSYS/LINEAR starting at
                                             Rev. 5.0
                                        and  ANSYS/LinearPlus starting at
                                             Rev. 5.0A.

     PC/THERMAL is equivalent to             WS/THERMAL at Rev. 4.4A,
                                        and  ANSYS/THERMAL starting at
                                             Rev. 5.0

     PREPPOST  contains relevant errors      the full ANSYS product, for
               shown for                     included pre- and post-
                                             processing functionality

     PC/MAGNETIC is equivalent to            ANSYS/Emag starting at Rev.
                                             5.0A

            ANSYS [Registered Trademark] CLASS3 ERROR REPORT

                                                          ERROR NO: 96-33

KEYWORDS:                     ASUM           VSUM

DESCRIPTION OF ERROR:

     The ASUM and VSUM commands may produce erroneous results due to poor
tesselation (tesselation is a triangular "mesh" of the surface used for
visualizing it) of the model surface.  We have observed this behavior
when there is a sharp change in angle for the model boundary.

FIRST INCORRECT VERSION(S):*_/          CORRECTED IN:*_/

Rev.  5.0                               Release 5.3
Component Products Rev. 5.0A            Component Products Release 5.3

SUGGESTED USER ACTION FOR RUNNING ON UNCORRECTED VERSION:

     In order to ascertain the quality of tesselation (and thus the
quality of the ASUM or VSUM results) for an area or volume, check the
areas and volumes from ASUM and VSUM commands with respect to the total
finite element areas and volumes (in POST1, use commands ETABLE,, VOLU
and SSUM) resulting from an acceptable mesh of that entity.

COMMENTS:

     1.  The corrected version gives accurate results for a valid
tesselation even if its quality is poor.

     2.  If the tesselation is invalid, but cannot be distinguished from
the plot of areas or volumes, the corrected version calculates the best
approximation and issues the following warning message:

          Poor tesselation for area "area number" resulted in poor
          surface area approximation.  Better area measure can be
          obtained from the elements of a refined mesh.

AUTHOR/CORRECTOR:                       DATE: August 7, 1996
                    Hasan Ahmad

REVIEWED BY QA:                         DATE: August 7, 1996
                    William J. Bryan

APPROVAL:                               DATE: August 7, 1996
                    John A. Swanson

_________________________
*_/ If a product name is not included in the "first incorrect version",
the full ANSYS program is implied.  For products not listed, this error
does not apply, but see the reverse side for equivalent product
designations.

Unless noted otherwise, this error report also applies to all revisions
after the first incorrect one and prior to the corrected revision.  All
revisions after "corrected in" are corrected.  Manual corrections are
included in on-line documentation as appropriate.  Please see the reverse
side of this sheet for additional information on ANSYS revision
identifiers.
_________________________

            ANSYS [Registered Trademark] CLASS3 ERROR REPORT

                                                          ERROR NO: 96-34

KEYWORDS:                     APDL           ARNODE

DESCRIPTION OF ERROR:

     The ANSYS Parametric Design Language (APDL) function ARNODE does not
return the correct area for mid-side node quadrilaterals which have been
reduced to triangles by duplicating nodes K, L, and O.  The calculated
area is low by 9/11ths.  SHELL93 is such an element.

FIRST INCORRECT VERSION(S):*_/          CORRECTED IN:*_/

Rev.  5.1                               Release 5.3
Component Products Rev.  5.2            Components Products Rev.  5.3

SUGGESTED USER ACTION FOR RUNNING ON UNCORRECTED VERSION:

COMMENTS:

AUTHOR/CORRECTOR:                  DATE: August 7, 1996
                    John Swanson

REVIEWED BY QA:                    DATE: August 7, 1996
                    William J. Bryan

APPROVAL:                          DATE: August 7, 1996
                    Mark C.  Imgrund

_________________________
*_/ If a product name is not included in the "first incorrect version",
the full ANSYS program is implied.  For products not listed, this error
does not apply, but see the reverse side for equivalent product
designations.

Unless noted otherwise, this error report also applies to all revisions
after the first incorrect one and prior to the corrected revision.  All
revisions after "corrected in" are corrected.  Manual corrections are
included in on-line documentation as appropriate.  Please see the reverse
side of this sheet for additional information on ANSYS revision
identifiers.
_________________________


            ANSYS [Registered Trademark] CLASS3 ERROR REPORT

                                                          ERROR NO: 96-35

KEYWORDS:      EMAG      ELEM53         PLANE53        CIRCUIT

DESCRIPTION OF ERROR:

     For circuit-fed axisymmetric massive conductor elements (PLANE53,
KEYOPT(1)=4), the calculation of JS in the SMISC record and JT in the
NMISC record are incorrect.  This will lead to an incorrect calculation
of total current (CURR2D command macro), power loss (POWERH command
macro), and the coupled-field joule heat generation rate input (LDREAD
command).

FIRST INCORRECT VERSION(S):*_/          CORRECTED IN:*_/

Rev.  5.2                               Release 5.3
ANSYS/Emag Rev.  5.2                    ANSYS/Emag Release 5.3

SUGGESTED USER ACTION FOR RUNNING ON UNCORRECTED VERSION:

     The sign on the source current density (JS) is incorrect.  This
leads to an incorrect calculation of the total current density (JT).  Use
the ETABLE command in POST1 to store values of JT, JS and JE.  Change the
sign of the JS results (SADD command), and then recalculate JT
(JT=JS+JE).

COMMENTS:

AUTHOR/CORRECTOR:                       DATE: August 7, 1996
                    Jian-She Wang

REVIEWED BY QA:                         DATE: August 7, 1996
                    William  J. Bryan

APPROVAL:                               DATE: August 7, 1996
                    John A.  Swanson

_________________________
*_/ If a product name is not included in the "first incorrect version",
the full ANSYS program is implied.  For products not listed, this error
does not apply, but see the reverse side for equivalent product
designations.

Unless noted otherwise, this error report also applies to ail revisions
after the first incorrect one and prior to the corrected revision.  All
revisions after "corrected in" are corrected.  Manual corrections are
included in on-line documentation as appropriate.  Please see the reverse
side of this sheet for additional information on ANSYS revision
identifiers.
_________________________

            ANSYS [Registered Trademark] CLASS3 ERROR REPORT

                                                          ERROR NO: 96-36

KEYWORDS: FLOTRAN   ELEM141   ELEM142   RESULTS FILE   DENSITY

DESCRIPTION OF ERROR:

     In flow analyses, for nodes on solid material (MAT>1) elements that
are connected only to solid material nodes, using elements FLUID141 and
FLUID142, documentation fails to specify that the quantity stored in the
results file position for density is actually the product of the density
and the specific heat.

FIRST INCORRECT VERSION(S):*_/          CORRECTED IN:*_/

Rev. 5.1                           Release 5.3 User's Guide
ANSYS/FLOTRAN Rev. 5.1

SUGGESTED USER ACTION FOR RUNNING ON UNCORRECTED VERSION:

COMMENTS:

     The method of storing solid material property information in the
results file for FLUID141 and 142 elements may be changed in the next
release to allow the density and the specific heat to be ally displayed
during post processing.

AUTHOR/CORRECTOR:                       DATE: August 7, 1996
                    Mike Normansell

REVIEWED BY QA:                         DATE: August 7, 1996
                    William J.  Bryan

APPROVAL:                               DATE: August 7, 1996
                    John A.  Swanson

_________________________
*_/ If a product name is not included in the "first incorrect version",
the full ANSYS program is implied.  For products not listed, this error
does not apply, but see the reverse side for equivalent product
designations.

Unless noted otherwise, this error report also applies to all revisions
after the first incorrect one and prior to the corrected revision.  All
revisions after "corrected in" are corrected.  Manual corrections are
included in on-line documentation as appropriate.  Please see the reverse
side of this sheet for additional information on ANSYS revision
identifiers.
_________________________

            ANSYS [Registered Trademark] CLASS3 ERROR REPORT

                                                          ERROR NO: 96-37

KEYWORDS: SFA  BOUNDARY CONDITIONS      SOLID MODEL    TRANSFER

DESCRIPTION OF ERROR:

     If a keypoint number is equal to or greater than 1024, boundary
conditions applied to the surface of a 3-D solid model volume (SFA
command) may not transfer to the underlying elements correctly.

FIRST INCORRECT VERSION(S):*_/          CORRECTED IN:*_/

Rev.  5.2                               Release 5.3

SUGGESTED USER ACTION FOR RUNNING ON UNCORRECTED VERSION:

     Verify that all area surface loads (SFA) have transferred correctly
(by listing or plotting), or use element surface load specifications (SFE
command).

COMMENTS:

     Solid model surface loads are transferred by the SFTRAN or SBCTRAN
commands or they are transferred automatically when the SOLVE command is
executed.

     In all error cases that we have seen, no loads have transferred; we
believe this to be the most likely manifestation of the error.

AUTHOR/CORRECTOR:                       DATE: August 7, 1996
                    Wa Kwok

REVIEWED BY QA:                         DATE: August 7, 1996
                    William J.  Bryan

APPROVAL:                               DATE: August 7, 1996
                    John A.  Swanson

_________________________
*_/ If a product name is not included in the "first incorrect version",
the full ANSYS program is implied.  For products not listed, this error
does not apply, but see the reverse side for equivalent product
designations.

Unless noted otherwise, this error report also applies to ail revisions
after the first incorrect one and prior to the corrected revision.  All
revisions after "corrected in" are corrected.  Manual corrections are
included in on-line documentation as appropriate.  Please see the reverse
side of this sheet for additional information on ANSYS revision
identifiers.
_________________________

            ANSYS [Registered Trademark] CLASS3 ERROR REPORT

                                                          ERROR NO: 96-38

KEYWORDS:      SOLID MODELING      BOOLEAN   SUBTRACT       ASBL

DESCRIPTION OF ERROR:

     The "SEPO" field of the solid modeling boolean command "ASBL" does
not always produce separate areas.  It may produce areas with separate
lines which share common keypoints.

     In most cases this error is obvious.  However, there may be rare
instances where the error could lead to unanticipated results if
validation of boundary conditions and loads is bypassed before solution
by the user.

FIRST INCORRECT VERSION(S):*_/          CORRECTED IN:*_/

Rev.  5.1                               Release 5.4
Component Products Rev. 5.1             Component Products Release 5.4

SUGGESTED USER ACTION FOR RUNNING ON UNCORRECTED VERSION:

     In Release 5.3, generate separate areas from unseparated areas by
using the "AGEN" command after the "ASBL" command.

COMMENTS:


AUTHOR/CORRECTOR:                       DATE: August 71 1996
                    Yu-Hua Ting

REVIEWED BY QA:                         DATE: August 7, 1996
                    William J.  Bryan

APPROVAL:                               DATE: August 7, 1996
                    John A.  Swanson

_________________________
*_/ If a product name is not included in the "first incorrect version",
the full ANSYS program is implied.  For products not listed, this error
does not apply, but see the reverse side for equivalent product
designations.

Unless noted otherwise, this error report also applies to all revisions
after the first incorrect one and prior to the corrected revision.  All
revisions after "corrected in" are corrected.  Manual corrections are
included in on-line documentation as appropriate.  Please see the reverse
side of this sheet for additional information on ANSYS revision
identifiers.
_________________________

                             ANSYS QA NOTICE

                                                       NOTICE NO: QA96-06

SUBJECT:       KUSE           MATRIX REUSE

DESCRIPTION:

     The program documentation has conflicting information on the
operation of the KUSE command.  The Theory Manual states that KUSE,-1
causes the program to reform the element matrices.  The Procedures and
Commands Manuals, however, state that KUSE,-1 only causes the
reformulation of the triangularized stiffness matrix (using the
previously formed element stiffness matrices).  The program functions as
reported in the Procedures and Command Manuals.

AFFECTED VERSIONS:  Rev.  5.0 through Rev. 5.2
                    Component Products Rev. 5.0A through Rev.  5.2

OTHER COMMENTS:

     To force reformulation of the element matrices, use NLGEOM,ON or
change material properties slightly, using a temperature-dependent
material.

     KUSE,-1 is rarely required in an analysis (only for some debugging
and certain cases of error avoidance).

     Several past Class3 errors (such as 94-68 R1, 93-33, 93-03, and 92-
25) incorrectly suggested that using KUSE,-1 was a way to avoid the
errors reported.

     At 5.3, the program is changed to operate as the Theory Manual
states.

AUTHOR:                                 DATE: August 7, 1996
               Peter Kohnke

REVIEWED BY QA:                         DATE: August 7, 1996
               William J.  Bryan

APPROVAL:                               DATE: August 7, 1996
               John A.  Swanson

            ANSYS [Registered Trademark] CLASS3 ERROR REPORT

                                                       ERROR NO: 92-25 R1

KEYWORDS: STIF18    STIF29    STIF60         PRESSURE FLEXIBILITY

DESCRIPTION OF ERROR:

     Results using STIF18 (the elastic curved pipe element) or STIF60
(the plastic curved pipe element) are incorrect if the pressure
contribution to the flexibility factor is included (KEYOPT(3)=1) and:

     1.   the pressure (P, EP, PSF or PPRES commands) is changed between
          iterations;

and 2.  the element matrix is reused.

The element matrix is reused unless:

     1.   material properties for the element are a function of
          temperature (MP, MPDATA commands);

or 2.  the full Newton-Raphson option (KAY,9,1) has been used.

[Strikeout: or 3.  KUSE, 1 has not been used to force reformulation.]

FIRST INCORRECT VERSION(S):*_/          CORRECTED IN:*_/

Rev. 2.0                                Rev. 5.0
PC Products Rev. 4.3                    PC Products Rev. 5.0

SUGGESTED USER ACTION FOR RUNNING ON UNCORRECTED VERSION:

     [Strikeout: Use KUSE, 1 to force the reformulation of the element
     matrices.]

COMMENTS:

     STIF18 was known as STIF29 prior to Rev. 4.3.

AUTHOR/CORRECTOR:                       DATE: August 7, 1996
                    David L.  Conover

REVIEWED BY QA:                         DATE August 7, 1996
                    William J. Bryan

APPROVAL:                               DATE: August 7, 1996
                    John A.  Swanson

_________________________
*_/ If a product name is not included in the "first incorrect version",
the full ANSYS program is implied.  For products not listed, this error
does not apply, but see the reverse side for equivalent product
designations.  Unless noted otherwise, this error report also applies to
all revisions after the first incorrect one and prior to the corrected
revision.  All revisions after "corrected in" are corrected.  Manual,
corrections are included in on-line documentation as appropriate.  Please
see the reverse side of this sheet for additional information on ANSYS
revision identifiers.
_________________________

            ANSYS [Registered Trademark] CLASS3 ERROR REPORT

                                                       ERROR NO: 93-03 R1

KEYWORDS:      KAN,-1         CONVECTION          TBULK

DESCRIPTION OF ERROR:

     If the bulk temperature is zero (TBULK=0) in a thermal convection
input (e.g., CV and CVSF commands), and the convection input is removed
in a later load step, the conductivity matrix of the applicable element
will not be reformulated to remove the convection condition unless KSS is
temperature-dependent [Strikeout: or the command KUSE, 1 has been input.]

FIRST INCORRECT VERSION(S):*_/          CORRECTED IN:*_/

Rev. 4.0                                Rev. 5.0
PC/THERMAL Rev. 4.2                     ANSYS/THERMAL Rev. 5.0

SUGGESTED USER ACTION FOR RUNNING ON UNCORRECTED VERSION:

[Strikeout: 1. Set KUSE, 1 to force the reformulation of all element
matrices. or]

          1.   Set TBULK to a small finite number (instead of zero).
or 2.  Make the thermal conductivity mildly KXX temperature-dependent.

COMMENTS:

AUTHOR/CORRECTOR:                       DATE: August 7, 1996
                    David L.  Conover

REVIEWED BY QA:                         DATE: August 7, 1996
                    William J.  Bryan

APPROVAL:                               DATE: August 7, 1996
                    John A.  Swanson

_________________________
*_/ If a product name is not included in the "first incorrect version",
the full ANSYS program is implied.  For products not listed, this error
does not apply, but see the reverse side for equivalent product
designations.

Unless noted otherwise, this error report also applies to all revisions
after the first incorrect one and prior to the corrected revision.  All
revisions after "corrected in" are corrected.  Manual corrections are
included in on-line documentation as appropriate.  Please see the reverse
side of this sheet for additional information on ANSYS revision
identifiers.
_________________________

            ANSYS [Registered Trademark] CLASS3 ERROR REPORT

                                                       ERROR NO: 93-33 R1

KEYWORDS: SHELL41        ELEM41         CLOTH OPTION

DESCRIPTION OF ERROR:

     The cloth option (KEYOPT(1)=2) of SHELL41 (the membrane shell
element) has the following errors:

1.   The elements are sometimes erroneously reported to be converged with
     both directions collapsed (STATUS=2) when there is actually a small
     amount of tension in one direction (STATUS=1).  The error does not
     occur if Poisson's ratio (NUXY or PRXY on the MP command) is 0.0.

2.   Elements with integration points that report tension in one
     direction and collapse in the other direction (STATUS=1) may not
     give correct answers.  The results may incorrectly depend on the
     order in which the loads are applied.

3.   If thermal strains are present, the results are incorrect.

4.   If KEYOPT(2)=0 (include extra displacement shapes [default]), the
     elements may be reported to be converged when in fact they are not.
     This is because the element stiffness matrices are sometimes not
     reformed when the status changes, which can cause incorrect results.

FIRST INCORRECT VERSION(S):*_/          CORRECTED IN:*_/

Rev.  4.0 - errors 1 & 2                Rev. 5.0A
Rev.  5.0 - errors 3 & 4                Rev. 5.0A

SUGGESTED USER ACTION FOR RUNNING ON UNCORRECTED VERSION:

     For error 2, rerunning the problem with a different order of loading
and achieving the same or similar results increases the reliability of
having the correct solution.  This assumes that there are no energy-
absorbing or other legitimately path-dependent effects (such as
plasticity) in the model.

     [Strikeout: For error 4, add the command KUSE, 1 before the first
SOLVE command to force reformulation of the stiffness matrix during each
iteration.]

COMMENTS:

     SHELL41 was referred to as STIF41 prior to Rev. 5.0.

AUTHOR/CORRECTOR:                       DATE: August 7, 1996
                    Peter Kohnke

REVIEWED BY QA:                         DATE: August 7, 1996
                    William J.  Bryan

APPROVAL:                               DATE: August 7, 1996
                    John A.  Swanson

_________________________
*_/ If a product name is not included in the "first incorrect version",
the full ANSYS program is implied.  For products not listed, this error
does not apply, but see the reverse side for equivalent product
designations.

Unless noted otherwise, this error report also applies to all revisions
after the first incorrect one and prior to the corrected revision.  All
revisions after "corrected in" are corrected.  Manual corrections are
included in on-line documentation as appropriate.  Please see the reverse
side of this sheet for additional information on ANSYS revision
identifiers.
_________________________

            ANSYS [Registered Trademark] CLASS3 ERROR REPORT

                                                       ERROR NO: 94-68 R2

KEYWORDS:      BEAM44    ELEM44    STIFFNESS      RELEASES

DESCRIPTION OF ERROR:

     There are two errors when using BEAM44 (3-D tapered unsymmetric beam
element) with stiffness releases.

1.   All results are in error for load steps, substeps, and iterations in
     which the element stiffness matrix is being re-used.

     Stiffness matrices are generally reused unless large deflections are
     active, or the materials or real constants are changing.  See
     Section 13.3 of the Theory Manual.

2.   All results are incorrect if any of the following are active:

        a.  Large deflection (NLGEOM,ON)
     or b.  Stress Stiffening (SSTIF,ON)
     or c.  Newton-Raphson (NROPT command).

FIRST INCORRECT VERSION(S):*_/     CORRECTED IN:*_/

Rev. 4.4                           Rev. 5.2
ANSYS/Linear Rev. 4.4              ANSYS/Linear Rev. 5.2

SUGGESTED USER ACTION FOR RUNNING ON UNCORRECTED VERSION:

[Strikeout: Error 1.     Use KUSE, 1 to force reformulation of all
                         element stiffness matrices.]

Error 2.  Use coincident coupled nodes (CP command) to induce the
          stiffness release where required.

COMMENTS:

     On some computer system, these errors will cause an abort.

     Stiffness releases are accessed with KEYOPT(7) and KEYOPT(8) or, if
using pre-Rev.  5.0 input, with KEYOPT(3) and KEYOPT(4).

     For error 2, if using pre-Rev. 5.0 input:

     a.   Large deflection is activated by the KAY,6,1 command.
     b.   Stress stiffening is activated by the KAY,8,1 command.
     c.   Newton-Raphson is activated by KAY,9,n (n = 1, 2 or 3).

AUTHOR/CORRECTOR:                       DATE: August 7, 1996
                    David L.  Conover

REVIEWED BY QA:                         DATE: August 7, 1996
                    William J.  Bryan

APPROVAL:                               DATE: August 7, 1996
                    John A.  Swanson

_________________________
*_/ If a product name is not included in the "first incorrect version",
the full ANSYS program is implied.  For products not listed, this error
does not apply, but see the reverse side for equivalent product
designations.  Unless noted otherwise, this error report also applies to
all revisions after the first incorrect one and prior to the corrected
revision.  All revisions after "corrected in" are corrected.  Manual
corrections are included in on-line documentation as appropriate.  Please
see the reverse side of this sheet for additional information on ANSYS
revision identifiers.
_________________________

            ANSYS [Registered Trademark] CLASS3 ERROR REPORT

                                                       ERROR NO: 95-37 R1

KEYWORDS:      FLOTRAN        FLUID142       ELEM142

DESCRIPTION OF ERROR:

     Three-dimensional FLOTRAN models using FLUID142 elements solved in
cylindrical coordinates (KEYOPT(3)=3) with a Z-direction acceleration
(ACEL command) yield incorrect velocity and pressure solutions.

FIRST INCORRECT VERSION(S):*_/          CORRECTED IN:*_/

Rev. 5.1                                [Redline: Release 5.4]
[Redline: ANSYS/Flotran Rev. 5.1]

SUGGESTED USER ACTION FOR RUNNING ON UNCORRECTED VERSION:

COMMENTS:

AUTHOR/CORRECTOR:                       DATE: August 8, 1996
                    Mark A. Troscinski

REVIEWED BY QA:                         DATE: August 8, 1996
                    William J.  Bryan

APPROVAL:                               DATE: August 8, 1996
                    John A.  Swanson

_________________________
*_/ If a product name is not included in the "first incorrect version",
the full ANSYS program is implied.  For products not listed, this error
does not apply, but see the reverse side for equivalent product
designations.

Unless noted otherwise, this error report also applies to all revisions
after the first incorrect one and prior to the corrected revision.  All
revisions after "corrected in" are corrected.  Manual corrections are
included in on-line documentation as appropriate.  Please see the reverse
side of this sheet for additional information on ANSYS revision
identifiers.
_________________________

                                                           FORM SASI-QA25
                                                           DEC 19, 1988

            ANSYS [Registered Trademark] CLASS3 ERROR REPORT

                                                       ERROR NO: 95-39 R1

KEYWORDS:      FLOTRAN        ELEM142        FLUID142

DESCRIPTION OF ERROR:

     Three-dimensional FLOTRAN models, using FLUID142 elements, solved in
Cartesian coordinates (KEYOPT(3)=0, default) yield incorrect pressure
solutions when solved with a rotating frame of reference (CGOMGA or OMEGA
commands).

FIRST INCORRECT VERSION(S):*_/          CORRECTED IN:*_/

Rev. 5.1                                [Redline: Release 5.4]
[Redline: ANSYS/Flotran Rev. 5.1]

SUGGESTED USER ACTION FOR RUNNING ON UNCORRECTED VERSION:

COMMENTS:

AUTHOR/CORRECTOR:                       DATE: August 8, 1996
                    Mark A.  Troscinski

REVIEWED BY QA:                         DATE: August 8, 1996
                    William J.  Bryan

APPROVAL:                               DATE: August 8, 1996
                    John Swanson

_________________________
*_/ If a product name is not included in the "first incorrect version",
the full ANSYS program is implied.  For products not listed, this error
does not apply, but see the reverse side for equivalent product
designations.

Unless noted otherwise, this error report also applies to all revisions
after the first incorrect one and prior to the corrected revision.  All
revisions after "corrected in" are corrected.  Manual corrections are
included in on-line documentation as appropriate.  Please see the reverse
side of this sheet for additional information on ANSYS revision
identifiers.
_________________________

            ANSYS [Registered Trademark] CLASS3 ERROR REPORT

                                                       ERROR NO: 95-49 R1

KEYWORDS:      FLOTRAN        ELEM141        ELEM142

DESCRIPTION OF ERROR:

     FLOTRAN models with triangular FLUID141 elements or tetrahedral
FLUID142 elements which use the transient, compressible flow algorithm
yield time-inaccurate velocity and pressure solutions if the flow is
supersonic.

FIRST INCORRECT VERSION(S):*_/          CORRECTED IN:*_/

Rev. 5.1                                [Redline: Release 5.4]
[Redline: ANSYS/Flotran Rev. 5.1]

SUGGESTED USER ACTION FOR RUNNING ON UNCORRECTED VERSION:

     Use quadrilateral FLUID141 or hexahedral FLUID142 elements instead.

COMMENTS:

AUTHOR/CORRECTOR:                       DATE: August 8, 1996
                    Mark A.  Troscinski

REVIEWED BY QA:                         DATE: August 8, 1996
                    William J.  Bryan

APPROVAL:                               DATE: August 8, 1996
                    John A. Swanson

_________________________
*_/ If a product name is not included in the "first incorrect version",
the full ANSYS program is implied.  For products not listed, this error
does not apply, but see the reverse side for equivalent product
designations.

Unless noted otherwise, this error report also applies to all revisions
after the first incorrect one and prior to the corrected revision.  All
revisions after "corrected in" are corrected.  Manual corrections are
included in on-line documentation as appropriate.  Please see the reverse
side of this sheet for additional information on ANSYS revision
identifiers.
_________________________

Table "ANSYS 5.1 CLASS3 ERROR SUMMARY BY REPORT NUMBER" 3 pages omitted.

Table "ANSYS 5.1 CLASS3 ERROR SUMMARY KEYWORD SORT OF ALL REVISION 5.1
CLASS3 ERRORS Date of this report: 8/12/96" 9 pages omitted.

                         ANSYS, Inc.
                         201 Johnson Road         Telephone 412.746.3304
                         Houston, PA 15342-1300   Facsimile 412.746.9494

September 23, 1996

Dear Class3 Error Recipient:

     Attached you will find ANSYS Class3 Error Reports 96-39, 96-40 and
96-41.  Also, included are ANSYS QA Notices QA96-07 and QA96-08.

     QA Notice QA96-07 is being issued to alert Silicon Graphics IRIX 6.2
Operating System users of a Silicon Graphics Operating System bug, which
may cause incorrect results when running the ANSYS program.

     QA Notice QA96-08 is being issued to clarify the documentation for
midside node generation.

          For your convenience, also enclosed are Class3 Error Report
Summaries for Revision 5.2 and Release 5.3, sorted both by Class3 Error
Number and by keyword.

                                        Sincerely,

                                        ANSYS, INC.

                                        William J.  Bryan
                                        Quality Assurance Manager

     ANSYS [Registered Trademark] a registered trademark off SAS IP

                                                             ANSYS.  Inc.

                                            ISO 9001 [logo omitted] A3721
                                           ISO 9001 CERTIFICATION INCLUDE
                                                  ALL COMMERCIAL PRODUCTS

                  ANSYS Revision Identifier Description


     ANSYS revision identifiers consist of a major revision level, a
minor revision level, a correction level, and occasionally a special
version level.  An example of how this is constructed is shown below:

                                5.0A--10
          major revision level          special version identifier

          minor revision level          correction level

     Major revision level changes indicate that new features have been
added to the program and that some level of program architecture change
and/or file structure has occurred.  Minor revision level changes also
indicate that new features have been added to the program, but files are
upwardly compatible.  ALI known error fixes are included in both minor
and major revisions.  Changes to the correction level indicate that it is
primarily an error correction release.  Special version identifiers
indicate that one or more additional minor changes have been made to the
program, normally to circumvent an error.  Special versions are not
general releases to all ANSYS licensees, since they typically represent
errors occurring only on one system, a subset of our customers who have
specific graphics devices, etc.

     The ANSYS revision identifier(s) shown under "corrected in" on the
front side of this Class3 Error Report indicates the first possible
revision that could contain the correction.  A major program change
needed to fix an error can dictate that the next minor or major revision
will contain the fix rather than the next correction level.  For example,
when errors were being reported while Rev.  4.3A was the latest
production version, most Class3 error reports indicated that 4.3B was the
"corrected in" revision.  Others requiring significant code restructuring
were reported as fixed in 4.4.  Rev.  4.3B was never released, but Rev.
4.4 contained all error corrections noted as fixed in 4.3B.

     An identifier indicated under "corrected in" does = guarantee that a
general release of that revision of ANSYS will occur.  It does indicate
that the correction is known and implemented in the coding that would be
part of that general release.

                     Equivalent Product Identifiers

     The ANSYS family of products occasionally undergoes name changes
between revisions and/or changes in the functionality of derived products
(such as ANSYS-PC/LINEAR).  To minimize the potential for confusion in
these areas, the important product name equivalent (similar program
functionality and error content) are listed below.

     ANSYS/ED  contains all errors      the full ANSYS product, starting
at             shown for                Rev.  5.0, and beyond, unless
                                        otherwise noted.,

     PC/LINEAR is equivalent to         WS/LINEAR at Rev. 4.4A,
                                   and  ANSYS/LINEAR starting at Rev.
                                        5.0.

     PC/THERMAL is equivalent to        WS/THERMAL at Rev. 4.4A,
                                   and  ANSYS/THERMAL starting at Rev.
                                        5.0.

     PREPPOST  contains relevant        the full ANSYS product, for
               errors shown for         included pre- and postprocessing
                                        functionality

            ANSYS [Registered Trademark] CLASS3 ERROR REPORT

                                                          ERROR NO: 96-39

KEYWORDS:      APDL           ARFACE              *GET

DESCRIPTION OF ERROR:

     The ANSYS Parametric Design Language *GET function ARFACE(E) may
produce incorrect results for triangular element faces.

FIRST INCORRECT VERSION(S):*_/          CORRECTED IN:*_/

Rev. 5.1                                Release 5.4
Component Products Rev. 5.1

SUGGESTED USER ACTION FOR RUNNING ON UNCORRECTED VERSION:

     Use the *GET function of AREAND(N1,N2,N3) instead.  The use of the
AREAND function is documented in the Commands Manual at the end of the
GET documentation.

COMMENTS:

     This error is due to an uninitialized variable.  ARFACE(E) has been
observed to either produce incorrect results,/abort out of the program,
or work correctly, depending upon the specific finite element model
and/or the computer system.

AUTHOR/CORRECTOR:                       DATE: September 11, 1996
                    Christopher W.  Aiken

REVIEWED BY QA:                         DATE: September 11, 1996
                    William J.  Bryan

APPROVAL:                               DATE: September 11, 1996
                    John K.  Swanson

_________________________
*_/ If a product name is not included in the "first incorrect version",
the full ANSYS program is implied.  For products not listed, this error
does not apply, but see the reverse side for equivalent product
designations.

Unless noted otherwise, this error report also applies to all revisions
after the first incorrect one and prior to the corrected revision.  All
revisions after "corrected in" are corrected.  Manual corrections are
included in on-line documentation as appropriate.  Please see the reverse
side of this sheet for additional information on ANSYS revision
identifiers.
_________________________

            ANSYS [Registered Trademark] CLASS3 ERROR REPORT

                                                          ERROR NO: 96-40

KEYWORDS:      PREP7     PIPE16         VALVE          BUNIF

DESCRIPTION OF ERROR:

     If the VALVE command of the PREP7 piping module is used to insert
one or more valve (PIPE16) elements in a piping run and the elements
connected to the valve element do not have element temperatures
specified, then element temperatures of 0.0 degrees will erroneously be
assigned to the PIPE16 valve elements.  Any uniform temperature specified
using the BFUNIF command will not be used in the solution for these
elements.

FIRST INCORRECT VERSION(S):*_/          CORRECTED IN:*_/

Rev. 5.0                                Release 5.4
ANSYS/LinearPlus Rev. 5.2

SUGGESTED USER ACTION FOR RUNNING ON UNCORRECTED VERSION:

     Before the solution, use the BFELIST command to list any
temperatures assigned to the PIPE16 elements and issue a BFDELE to delete
any erroneous temperatures for the affected PIPE16 valve elements.

COMMENTS:

AUTHOR/CORRECTOR:                       DATE: September 20, 1996
                    Christopher W.  Aiken

REVIEWED BY QA:                         DATE: September 20, 1996
                    William J.  Bryan

APPROVAL:                               DATE: September 20, 1996
                    John A.  Swanson

_________________________
*_/ If a product name is not incLuded in the "first incorrect version",
the full ANSYS program is implied.  For products not listed, this error
does not apply, but see the reverse side for equivalent product
designations.

Unless noted otherwise, this error report also applies to all revisions
after the first incorrect one and prior to the corrected revision.  All
revisions after "corrected in" are corrected.  Manual corrections are
included in on-line documentation as appropriate.  Please see the reverse
side of this sheet for additional information on ANSYS revision
identifiers.
_________________________

            ANSYS [Registered Trademark] CLASS3 ERROR REPORT

                                                          ERROR NO: 96-41

KEYWORDS:      ELEM150   SHELL150  ELEMENT VOLUME      ETABLE    *GET

DESCRIPTION OF ERROR:

     The element volume for SHELL150 is obtained from the ETABLE command
in POST1 or the *GET for element volume after a solution is incorrect

FIRST INCORRECT VERSION(S):*_/          CORRECTED IN:*_/

Rev. 5.2                                Release 5.4
Component Products Rev. 5.2

SUGGESTED USER ACTION FOR RUNNING ON UNCORRECTED VERSION:

     Multiply the reported number by the shell thickness to obtain a
correct value of volume.  This suggestion is valid for elements with
constant thickness.

COMMENTS:

AUTHOR/CORRECTOR:                       DATE: September 20, 1996
                    Tim Pawlak

REVIEWED BY QA:                         DATE: September 20, 1996
                    William J.  Bryan

APPROVAL:                               DATE: September 20, 1996
                    John A.  Swanson

_________________________
*_/ If a product name is not included in the "first incorrect version",
the full ANSYS program is implied.  For products not listed, this error
does not apply, but see the reverse side for equivalent product
designations.

Unless noted otherwise, this error report also applies to all revisions
after the first incorrect one and prior to the corrected revision.  All
revisions after "corrected in" are corrected.  Manual corrections are
included in on-line documentation as appropriate.  Please see the reverse
side of this sheet for additional information on ANSYS revision
identifiers.
_________________________

                             ANSYS QA NOTICE

                                                       NOTICE NO: QA96-07

SUBJECT:  SYSTEM         SILICON GRAPHICS         IRIX 6.2

DESCRIPTION:

     The Silicon Graphics IRIX 6.2 operating system contains a bug that
affects proper execution of ANSYS owing to a formatting error for
numerical output.  The IRIX 6.2 Patch 1457 contains a bug fix that fully
corrects this problem.  The effect of this error is that some numbers
printed by the ANSYS program on platforms with this operating system
version are too small (by a factor of 10).  For example, a number that
should be 100000.  appears as 10000.

     Although this bug is not a bug in the ANSYS program, we are
notifying our customers due to the incorrect results it can produce using
the ANSYS program.

AFFECTED VERSIONS:       Silicon Graphics IRIX 6.2 Operating System (any
                         ANSYS versions run at this level)

CORRECTED IN:

     Patch 1457 can be obtained via the SGI patch server.  See the SGI
Web Page at http://www.sgi.com.  Patch 1457 is also available on the
ANSYS Web Page at http://www.ansys.com in the Services and Support area.
Where customers do not have Internet access, SGI Service Engineers can be
called upon to install the patch at 1-800-800-4SGI.

SUGGESTED USER ACTION: Customers must obtain this corrective patch from
SGI to remedy this error.

AUTHOR:                                 DATE: September 20, 1996
                    John Fortuna

REVIEWED BY QA:                         DATE: September 20, 1996
                    William J.  Bryan

APPROVAL:                               DATE: September 20, 1996
                    John A.  Swanson

                             ANSYS QA NOTICE

                                                       NOTICE NO: QA96-08

SUBJECT:  DIRECT MODEL GENERATION       ELEMENTS       MIDSIDE NODES

DESCRIPTION:   The ANSYS program documentation regarding geometric
locations for midside nodes is potentially confusing.  For some higher
order (midside node) elements (such as PLANE2, PLANE82, SOLID95, etc.),
the ANSYS Elements Manual contains statements similar to the following:

     Midside nodes may be removed (with a zero node number) to form a
     pattern compatible with other element types.  The geometric
     locations of midside nodes are automatically calculated, if not
     supplied.

The following clarification is provided to reduce the potential for
confusion and/or misinterpretation regarding the program behavior that
this statement describes.

When defining midside node elements using the direct generation method
(i.e., the E, EN, etc.  commands), midside nodes are created and located
according to the following:

     Some higher order elements permit the removal of midside nodes.  For
     such elements, if a zero value (or blank) is used for a midside node
     when the element is defined, the corresponding midside node is
     REMOVED from the element.  As a result, some or all of the quadratic
     terms (depending on the number of removed midside nodes) in the
     element's shape functions are ignored, thus forcing the element
     edge(s) to be and remain straight.  This is typically done to
     compatibly connect higher order (midside node) elements to lower
     order (non-midside node) elements.  In the extreme case of an
     element with all of its midside nodes removed, the element will use
     linear shape functions, thus producing results comparable to the
     analogous lower order (non-midside node) element type with extra
     displacement shapes suppressed.

     When defining a higher order element, if a node number is used for a
     midside node and that node has not yet been defined (N, NGEN, FILL,
     NSYM, etc.), then the node will be automatically defined and given a
     geometric location that is the calculated mid-point (linearly
     interpolated in Cartesian coordinates) between its respective corner
     nodes.  Nodal rotations for such nodes will also be automatically
     calculated by linearly interpolating between the nodal rotation
     angles of the corner nodes.  This allows the user to create midside
     node elements without explicitly defining the geometric locations
     for midside nodes that are located midway between the corner nodes.

Note that this behavior applies only to the direct model generation
method.  Controls regarding midside nodes in meshed models are provided
in the meshing controls of the ANSYS program (ESHAPE command).

AFFECTED VERSIONS:  Revision 4.0 through Release 5.3
                    Component Products Revision 4.3 through Release 5.3

COMMENTS:      In Release 5.4, documentation regarding direct generation
and midside node elements will be clarified.

AUTHOR:                                 DATE: September 20, 1996
                    Kenneth G.  Podlaszewski

VIEWED BY QA: DATE:                     DATE: September 20, 1996
                    William J.  Bryan

APPROVAL:                               DATE: September 20, 1996
                    John A.  Swanson

Table  "ANSYS 5.2 CLASS3 ERROR SUMMARY BY REPORT NUMBER" 2 pages omitted.

Table  "ANSYS 5.2 CLASS3 ERROR SUMMARY KEYWORD SORT OF ALL REVISION
5.2
CLASS3 ERRORS Date of this report: 9/24/96" 5 pages omitted.

Table  "ANSYS 5.3 CLASS3 ERROR SUMMARY KEYWORD SORT OF ALL REVISION
5.3
CLASS3 ERRORS Date of this report: 9/24/96" omitted.

*** END OF DOCUMENT ***