Exhibit 8.1


                  [COOLEY GODWARD LLP LETTERHEAD]

July 27, 2001



The Titan Corporation
3033 Science Park Road
San Diego, CA  92121-1199

Ladies and Gentlemen:

This opinion is being delivered to you in connection with the Form S-4
Registration Statement (the "Registration Statement") filed in connection with
(i) the exchange offer (the "Offer") proposed to be made by The Titan
Corporation, a Delaware corporation ("Parent"), through its wholly-owned
subsidiary, Gem Acquisition Corp., a Delaware corporation ("Merger Sub"), to
exchange shares of Parent for shares of Datron Systems Incorporated, a Delaware
corporation (the "Company"), and (ii) the proposed merger of Merger Sub with and
into the Company (the "Merger"), in each case pursuant to the Agreement and Plan
of Merger and Reorganization dated as of June 24, 2001 (the "Reorganization
Agreement"), by and among Parent, Merger Sub, and the Company. Except as
otherwise provided, capitalized terms used but not defined herein shall have the
meanings set forth in the Reorganization Agreement.

We have acted as counsel to Parent in connection with the Offer and the Merger.
As such, and for the purpose of rendering this opinion, we have examined, and
are relying upon (without any independent investigation or review thereof) the
truth and accuracy, at all relevant times, of the statements, covenants,
representations and warranties contained in the following documents (including
all exhibits and schedules attached thereto):

         (a)      the Reorganization Agreement;

         (b)      the Registration Statement, which includes the Preliminary
Prospectus of Parent (the "Preliminary Prospectus");

         (c)      those certain tax representation letters of even date herewith
delivered to us by Parent, Merger Sub and the Company (the "Tax Representation
Letters"); and

         (d)      such other instruments and documents related to the formation,
organization and operation of Parent, Merger Sub and the Company and to the
consummation of the Offer and the Merger and the other transactions
contemplated by the Reorganization Agreement as we have deemed necessary or
appropriate.

In connection with rendering this opinion, we have assumed (without any
independent investigation or review thereof) that:




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July 27, 2001
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         (a) Original documents submitted to us (including signatures thereto)
are authentic, documents submitted to us as copies conform to the original
documents, and that all such documents have been (or will be by the closing of
the Offer or the Effective Time of the Merger, as the case may be) duly and
validly executed and delivered where due execution and delivery are a
prerequisite to the effectiveness thereof;

         (b) All representations, warranties and statements made or agreed to by
Parent, Merger Sub and the Company, their managements, employees, officers,
directors and stockholders in connection with the Offer and the Merger,
including, but not limited to, those set forth in the Reorganization Agreement
(including the exhibits thereto) and the Tax Representation Letters are true and
accurate at all relevant times and any representation or statement made "to the
knowledge of" or similarly qualified is correct without such qualification;

         (c) All covenants contained in the Reorganization Agreement (including
exhibits thereto) and the Tax Representation Letters are performed without
waiver or breach of any material provision thereof;

         (d) The Merger will qualify as a statutory merger under the laws of the
State of Delaware; and

         (e) The opinion of even date herewith rendered by Heller Ehrman White &
McAuliffe LLP to the Company and filed as Exhibit 8.2 to the Registration
Statement has been delivered and has not been withdrawn.

Based on our examination of the foregoing items and subject to the limitations,
qualifications, assumptions and caveats set forth herein, we are of the opinion
that the discussion entitled "Material Federal Income Tax Consequences"
contained in the Preliminary Prospectus, insofar as it relates to statements of
law and legal conclusions, sets forth the material federal income tax
considerations generally applicable to the Offer and the Merger.

This opinion does not address the various state, local or foreign tax
consequences that may result from the Offer and the Merger or the other
transactions contemplated by the Reorganization Agreement. In addition, no
opinion is expressed as to any federal income tax consequence of the Offer or
Merger or the other transactions contemplated by the Reorganization Agreement
except as specifically set forth herein, and this opinion may not be relied upon
except with respect to the consequences specifically discussed herein.

No opinion is expressed as to any transaction other than the Offer and the
Merger as described in the Reorganization Agreement, or as to any transaction
whatsoever, including the Offer and the Merger, if any of the representations,
warranties, statements and assumptions material to our




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July 27, 2001
Page Three

opinion and upon which we have relied are not accurate and complete in all
material respects at all relevant times.

This opinion only represents our best judgment as to the federal income tax
consequences of the Offer and the Merger and is not binding on the Internal
Revenue Service or any court of law, tribunal, administrative agency or other
governmental body. The conclusions are based on the Internal Revenue Code of
1986, as amended, existing judicial decisions, administrative regulations and
published rulings. Because this opinion is being delivered prior to the
Effective Time of the Merger, it must be considered prospective and dependent on
future events. No assurance can be given that future legislative, judicial or
administrative changes or interpretations would not adversely affect the
accuracy of the conclusions stated herein. Nevertheless, by rendering this
opinion, we undertake no responsibility to advise you of any new developments in
the application or interpretation of the federal income tax laws.

This opinion is being delivered solely in connection with the filing of the
Registration Statement. It may not be relied upon, made available or utilized
for any other purpose without our prior written consent.

We consent to the reference to our firm under the caption "Material Federal
Income Tax Consequences" in the Preliminary Prospectus and to the reproduction
and filing of this opinion as an exhibit to the Registration Statement.

Sincerely,


COOLEY GODWARD LLP

/s/ WEBB B. MORROW III

Webb B. Morrow III

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