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                                                                    EXHIBIT 10.2

                           ADDENDUM TO THE AMENDED AND
                          RESTATED SEVERANCE AGREEMENT


         This Addendum to the Amended and Restated Severance Agreement (this
"Addendum") is made and entered into effective as of this 16th day of April,
1999, by and among Aviall, Inc., a Delaware corporation (the "Company"),
Inventory Locator Service, LP, a Delaware limited partnership ("ILS"), and Bruce
Langsen (the "Executive"). Terms used in this Addendum with initial capital
letters that are defined in the Amended and Restated Severance Agreement, dated
as of April 16, 1999, between the Company and the Executive (the "Severance
Agreement") are used in this Addendum as so defined.

         WHEREAS, the Board of Directors of the Company has authorized
management to examine a range of possible transactions, which may include a
sale, joint venture or other transaction involving the Company or either of its
two operating businesses; and

         WHEREAS, the Severance Agreement provides for certain severance
benefits in the event of a termination of the Executive's employment following a
Change of Control of the Company; and

         WHEREAS, a sale of ILS would not constitute a Change of Control of the
Company for the purposes of the Severance Agreement; and

         WHEREAS, the Company desires to provide the Executive with the benefits
intended to be provided to the Executive under the Severance Agreement in
circumstances which both the Company and ILS are sold in a series of
transactions;

         NOW, THEREFORE, in order to induce the Executive to remain in the
employ of ILS and other good and valuable consideration, the Company, ILS and
the Executive agree as follows:

         1. In the event that a sale of ILS is completed and, on or prior to the
closing date of such sale, the Company has entered into a definitive agreement
the consummation of which would result in a Change of Control of the Company, a
Change of Control shall be deemed to have occurred for the purposes of the
Severance Agreement effective as of the closing date of the sale of ILS, without
regard to whether a Change of Control with respect to the Company ultimately
occurs. For the purposes of this Addendum, a "sale of ILS" shall mean the sale
or other transfer (whether direct or indirect, by sale, merger, consolidation or
otherwise) of (i) the general and limited partnership interests of ILS, (ii) the
capital stock of Inventory Locator Service GP, Inc. and ILS Investor, Inc. or
(iii) the sale of all or substantially all of the assets of ILS. Except as
otherwise provided in this Section 1, the definition of Change of Control shall
otherwise remain as set forth in the Severance Agreement.



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         2. Effective as of the sale of ILS, ILS shall automatically and without
further action, assume all of the rights and obligations of the Company under
the Severance Agreement and the Company shall be released from all such
obligations and ILS shall be deemed to be the "Company" for the purpose of the
Severance Agreement. The Company and ILS shall require any successor (whether
direct or indirect, by purchase, merger, consolidation or otherwise) to all or
substantially all of the business or assets of ILS, to expressly assume and
agree to perform the Severance Agreement, as modified by this Addendum, in the
same manner and to the same extent the Company would be required to perform if
no such succession had taken place.

         3. The Severance Agreement, as modified by this Addendum, remains in
full force and effect.

         IN WITNESS WHEREOF, the Company, ILS and the Executive have executed,
or caused to be executed, this Addendum effective as of the day and year first
written above.

         AVIALL, INC.



         By: /s/ Eric E. Anderson                                             
             ------------------------------------------
             Eric E. Anderson, Chairman, President
             and Chief Executive officer

         INVENTORY LOCATOR SERVICE, LP

         By: Inventory Locator Service GP, Inc.,
             its General Partner


         By: /s/ Jeffrey J. Murphy
             ------------------------------------------
             Jeffrey J. Murphy,
             Vice President



         /s/ Bruce Langsen
         ----------------------------------------------
         Bruce Langsen

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