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                                   Exhibit 5.1


                          [LATHAM & WATKINS LETTERHEAD]



                                February 4, 1997

ViaSat, Inc.
2290 Cosmos Court
Carlsbad, California 92009

         Re:  Form S-8 Registration Statement;
              1,358,472 Shares of Common Stock

Ladies and Gentlemen:

         In connection with the registration by ViaSat, Inc., a Delaware
corporation (the "Company"), of 1,358,472 shares of common stock, par value
$.0001 per share (the "Shares"), of the Company to be issued pursuant to (i) The
1996 Equity Participation Plan of ViaSat, Inc., (ii) The ViaSat, Inc. Employee
Stock Purchase Plan and (iii) the ViaSat, Inc. 1993 Stock Option Plan, under the
Securities Act of 1933, as amended (the "Act"), on a Registration Statement on
Form S-8 filed with the Securities and Exchange Commission on February 4, 1997
(as amended from time to time, the "Registration Statement"), you have requested
our opinion with respect to the matters set forth below.

         In our capacity as your counsel in connection with such registration,
we are familiar with the proceedings taken and proposed to be taken by the
Company in connection with the authorization, issuance and sale of the Shares,
and for the purposes of this opinion, have assumed such proceedings will be
timely completed in the manner presently proposed. In addition, we have made
such legal and factual examinations and inquiries, including an examination of
originals or copies certified or otherwise identified to our satisfaction of
such documents, corporate records and instruments, as we have deemed necessary
or appropriate for purposes of this opinion.

         In our examination, we have assumed the genuineness of all signatures,
the authenticity of all documents submitted to us as originals, and the
conformity to authentic original documents of all documents submitted to us as
copies.

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ViaSat, Inc.
February 4, 1997
Page 2

         We are opining herein as to the effect on the subject transaction only
of the General Corporation Law of the State of Delaware, and we express no
opinion with respect to the applicability thereto, or the effect thereon, of the
laws of any other jurisdiction or any other laws, or as to any matters of
municipal law or the laws of any other local agencies within the state.

         Subject to the foregoing, it is our opinion that as of the date hereof
the Shares have been duly authorized, and, upon the issuance of and payment for
the Shares in accordance with the terms set forth in the respective stock option
plans under which such Shares will be issued and sold, the Shares will be
validly issued, fully paid and nonassessable.

         We consent to your filing this opinion as an exhibit to the
Registration Statement.

                                            Very truly yours,


                                            /s/ LATHAM & WATKINS