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                                                                   Exhibit 5.1



                              September 20, 2000



Aviation Group, Inc.
700 North Pearl Street
Suite 2170
Dallas, Texas 75201

     Re:  Registration Statement on Form S-4 (File No. 333-40352)

Gentlemen:

We refer to the Form S-4 Registration Statement of Aviation Group, Inc., a Texas
corporation (the "Company"), filed with the Securities and Exchange Commission,
and the Joint Proxy Statement/Prospectus and Prospectus Supplement contained
therein (the "Registration Statement"), for the purpose of registering under the
Securities Act of 1933, as amended, 135,000,000 shares of the Company's common
stock, $0.01 par value per share (the "Common Shares") and 2,160 shares of the
Company's Series C convertible preferred stock, $0.01 par value (the "Series C
Preferred Shares"). The Common Shares are to be issued in exchange for
exchangeable shares (the "Exchangeable Shares") of travelbyus.com ltd., an
Ontario corporation ("travelbyus") that are to be issued in connection with a
proposed arrangement under Ontario, Canada law (the "Arrangement") pursuant to
the Arrangement Agreement and Plan of Arrangement, dated as of May 3, 2000 (the
"Arrangement Agreement"), between the Company, travelbyus and the Company's
subsidiary, Aviation Group Canada Ltd.  The Series C Preferred Shares are to be
issued pursuant to an exchange offer (the "Exchange Offer") made in connection
with the Arrangement whereby holders of outstanding shares of the Company's
Series B preferred stock (the "Series B Preferred Shares") may exchange their
Series B Preferred Shares for Series C Preferred Shares on a one-to-one ratio.

We note that, pursuant to the terms of the Arrangement Agreement, (i) the
issuance of the Common Shares is dependent upon approval by the Company's
shareholders of an amendment to the Company's articles of incorporation
increasing the number of authorized Common Shares, (ii) the issuance of the
Series C Preferred Shares is dependent upon approval by the Company's
shareholders as required by the rules of the Nasdaq Stock Market, Inc. to
maintain the Company's listing on the Nasdaq SmallCap Market, and (iii) the
issuance of both the Common Shares and the Series C Preferred Shares is
dependent upon shareholder approval of and the subsequent consummation of the
Arrangement.
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Aviation Group, Inc.
September 20, 2000
Page 2


We have examined copies, certified or otherwise identified to our satisfaction,
of the Company's Articles of Incorporation and Amended and Restated Bylaws,
including any and all amendments thereto, and minutes of applicable meetings of
the shareholders and the board of directors of the Company, or written consents
in lieu of such meetings,  together with such other corporate records and
certificates of public officials and of officers of the Company as we have
deemed relevant for the purposes of this opinion.  For purposes of our opinions
herein, we have assumed that all relevant corporate actions heretofore taken by
the Company remain in full force and effect at all relevant times with respect
to the matters opined on herein, and that the Arrangement is properly approved
and consummated as contemplated in the Arrangement Agreement.

Based upon the foregoing, and giving regard to the legal considerations that we
deem relevant, it is our opinion that:

1.   Assuming that the increase in number of Common Shares described in the
     Registration Statement is properly approved and effected, all necessary
     corporate actions on the part of the Company will have been taken to
     authorize the issuance of the Common Shares in exchange for Exchangeable
     Shares.

2.   Assuming that the increase in the authorized number of Common Shares
     described in the Registration Statement is properly approved and effected,
     and that the issuance of the Series C Preferred Shares is approved by the
     appropriate number of shareholders of the Company, all necessary corporate
     actions on the part of the Company will have been taken to authorize the
     issuance of the Series C Preferred Shares in exchange for the Series B
     Preferred Shares.

3.   Assuming that the increase in the authorized number of Common Shares
     described in the Registration Statement is properly approved and effected,
     if and when the Common Shares are issued and delivered by the Company in
     accordance with the terms and conditions of the Exchangeable Shares and as
     contemplated by the Registration Statement, the Common Shares will be
     legally issued, fully paid, and nonassessable.

4.   Assuming that the increase in the authorized number of Common Shares
     described in the Registration Statement is properly approved and effected,
     and that the issuance of the Series C Shares is approved by the appropriate
     number of shareholders of the Company, if and when the Series C Preferred
     Shares are issued and delivered by the Company in accordance with the terms
     and conditions of the Exchange Offer and as contemplated by the
     Registration Statement, the Series C Preferred Shares will be legally
     issued, fully paid, and nonassessable.
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Aviation Group, Inc.
September 20, 2000
Page 3


5.   Assuming that the Series C Preferred Shares are converted in accordance
     with the terms thereof, the Common Shares to be issued upon such conversion
     will be legally issued, fully paid and nonassessable.

We are attorneys admitted to practice in the State of Texas.  We express no
opinion concerning the laws of any jurisdiction other than the laws of the
United States of America and the State of Texas.

We hereby consent to the reference to us under the caption "Legal Matters" in
the Joint Proxy Statement/Prospectus and the Prospectus Supplement, which
constitute a part of the Registration Statement.  In giving our consent, we do
not thereby admit that we are in the category of persons whose consent is
required under Section 7 of the Act or the rules and regulations of the
Securities and Exchange Commission thereunder.

                              Sincerely,

                              JENKENS & GILCHRIST,
                              a Professional Corporation



                              By: /s/ Daryl B. Robertson
                                  ----------------------------------------
                                  Daryl B. Robertson, Authorized Signatory