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                                                                     Exhibit 3.8

                             AEROSONIC CORPORATION

                                    BY-LAWS

                                   ARTICLE I

                                    OFFICES

     Section 1. The registered office shall be in the City of Wilmington, County
of New Castle, State of Delaware.

     Section 2. The corporation may also have offices at such other places both
within and without the State of Delaware as the Board of Directors may from time
to time determine or the business of the corporation may require.

                                   ARTICLE II

                            MEETINGS OF STOCKHOLDERS

     Section 1. All meetings of the stockholders for the election of directors
shall be held in the City of Clearwater, State of Florida, at such place as may
be fixed from time to time by the Board of Directors, or at such other place
either within or without the State of Delaware as shall be designated from time
to time by the Board of Directors and stated in the notice of the meeting.
Meetings of stockholders for any other purpose may be held at such time and
place, within or without the State of Delaware, as shall be stated in the notice
of the meeting or in a duly executed waiver of notice thereof.

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     Section 2. Annual meetings of stockholders, commencing with the year 1970,
shall be held on the second Friday in July, if not a legal holiday, and if a
legal holiday, then on the next secular day following, at 10:00 A.M., or at such
other date and time as shall be designated from time to time by the Board of
Directors and stated in the notice of the meeting, at which they shall elect by
a plurality vote, by written ballot, a Board of Directors, and transact such
other business as may properly be brought before the meeting.

     Section 3. Written notice of the annual meeting stating the place, date and
hour of the meeting shall be given to each stockholder entitled to vote at such
meeting not less than ten nor more than fifty days before the date of the
meeting.

     Section 4. The officer who has charge of the stock ledger of the
corporation shall prepare and make, at least ten days before every meeting of
stockholders, a complete list of the stockholders entitled to vote at the
meeting, arranged in alphabetical order, and showing the address of each
stockholder and the number of shares registered in the name of each stockholder.
Such list shall be open the the examination of any stockholder, for any purpose
germane to the meeting, during ordinary business hours, for a period of at least
ten days prior to the meeting, either at a place within the city where the
meeting is to be held, which place shall be specified in the notice of the
meeting, or, if not so specified, at the place where the meeting is to be held.
The list shall also

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be produced and kept at the time and place of the meeting during the whole time
thereof, and may be inspected by any stockholder who is present.

     Section 5. Special meetings of the stockholders, for any purpose or
purposes, unless otherwise prescribed by statute or by the certificate of
incorporation, may be called by the president and shall be called by the
president or secretary at the request in writing of a majority of the Board of
Directors, or at the request in writing of stockholders owning a majority in
amount of the entire capital stock of the corporation issued and outstanding and
entitled to vote. Such request shall state the purpose or purposes of the
proposed meeting.

     Section 6. Written notice of a special meeting stating the place, date and
hour of the meeting and the purpose or purposes for which the meeting is called,
shall be given not less than ten nor more than fifty days before the date of the
meeting, to each stockholder entitled to vote at such meeting.

     Section 7. Business transacted at any special meeting of stockholders shall
be limited to the purposes stated in the notice.

     Section 8. The holders of a majority of the stock issued and outstanding
and entitled to vote thereat, present in person or represented by proxy, shall
constitute a quorum at all meetings of the stockholders for the transaction of
business except as otherwise provided by statute or by the certificate of
incorporation. If, however, such quorum shall not be present or

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represented at any meeting of the stockholders, the stockholders entitled to
vote thereat, present in person or represented by proxy, shall have power to
adjourn the meeting from time to time, without notice other than announcement at
the meeting, until a quorum shall be present or represented. At such adjourned
meeting, at which a quorum shall be present or represented, any business may be
transacted which might have been transacted at the meeting as originally
notified. If the adjournment is for more than thirty days, or if after the
adjournment a new record date is fixed for the adjourned meeting, a notice of
the adjourned meeting shall be given to each stockholder of record entitled to
vote at the meeting.

     Section 9. When a quorum is present at any meeting, the vote of the holders
of a majority of the stock having voting power present in person or represented
by proxy shall decide any question brought before such meeting, unless the
question is one upon which by express provision of the statutes or of the
certificate of incorporation, a different vote is required in which case such
express provision shall govern and control the decision of such question.

     Section 10. Each stockholder shall at every meeting of the stockholders be
entitled to one vote in person or by proxy for each share of the capital stock
having voting power held by such stockholder, but no proxy shall be voted on
after three years from its date, unless the proxy provides for a longer period.

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     Section 11. Whenever the vote of stockholders at a meeting thereof is
required or permitted to be taken for or in connection with any corporate
action, by any provision of the statutes, the meeting and vote of stockholders
may be dispensed with if all of the stockholders who would have been entitled to
vote upon the action of such meeting were held shall consent in writing to such
corporate action being taken; or if the certificate of incorporation authorizes
the action to be taken with the written consent of the holders of less than all
of the stock who would have been entitled to vote upon the action if a meeting
were held, then on the written consent of the stockholders having not less than
such percentage of the total number of votes as may be authorized in the
certificate of incorporation; provided that in no case shall the written consent
be by the holders of stock having less than the minimum percentage of the total
vote required by statute for the proposed corporate action, and provided that
prompt notice must be given to all stockholders of the taking of corporate
action without a meeting and by less than unanimous written consent.

                                  ARTICLE III

                                   DIRECTORS

     Section 1. The number of directors which shall constitute the whole board
shall be not less than three nor more than seven. The first board shall consist
of four directors. Thereafter, within the limits above specified, the number of
directors shall be

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determined by resolution of the Board of Directors or by the stockholders at the
annual meeting. The directors shall be elected at the annual meeting of the
stockholders, except as provided in Section 2 of this Article, and each director
elected shall hold office until his successor is elected and qualified.
Directors need not be stockholders.

     Section 2. Vacancies and newly created directorships resulting from any
increase in the authorized number of directors may be filled by a majority of
the directors then in office, though less than a quorum, or by a sole remaining
director, and the directors so chosen shall hold office until the next annual
election and until their successors are duly elected and shall qualify, unless
sooner displaced. If there are no directors in office, then an election of
directors may be held in the manner provided by statute. If, at the time of
filling any vacancy or any newly created directorship, the directors then in
office shall constitute less than a majority of the whole board (as constituted
immediately prior to any such increase), the Court of Chancery may, upon
application of any stockholder or stockholders holding at least ten per cent of
the total number of the shares at the time outstanding having the right to vote
for such directors, summarily order an election to be held to fill any such
vacancies or newly created directorships, or to replace the directors chosen by
the directors then in office.

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     Section 3. The business of the corporation shall be managed by its Board of
Directors which may exercise all such powers of the corporation and do all such
lawful acts and things as are not by statute or by the certificate of
incorporation or by these by-laws directed or required to be exercised or done
by the stockholders.

                       MEETINGS OF THE BOARD OF DIRECTORS

     Section 4. The Board of Directors of the corporation may hold meetings,
both regular and special, either within or without the State of Delaware.

     Section 5. The first meeting of each newly elected board of directors shall
be held at such time and place as shall be fixed by the vote of the stockholders
at the annual meeting and no notice of such meeting shall be necessary to the
newly elected directors in order legally to constitute the meeting, provided a
quorum shall be present. In the event of the failure of the stockholders to fix
the time or place of such first meeting of the newly elected Board of Directors,
or in the event such meeting is not held at the time and place so fixed by the
stockholders, the meeting may be held at such time and place as shall be
specified in a notice given as hereinafter provided for special meetings of the
Board of Directots, or as shall be specified in a written waiver signed by all
of the directors.

     Section 6. Regular meetings of the Board of Directors may be held without
notice at such time and at such place as shall from time to time be determined
by the board.

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     Section 7. Special meetings of the board may be called by the president on
one day's notice to each director, either personally or by mail or by telegram;
special meetings shall be called by the president or secretary in like manner
and on like notice on the written request of two directors.

     Section 8. At all meetings of the board, a majority of the directors shall
constitute a quorum for the transaction of business and the act of a majority of
the directors present at any meeting at which there is a quorum shall be the act
of the Board of Directors, except as may be otherwise specifically provided by
statute or by the certificate of incorporation. If a quorum shall not be present
at any meeting of the Board of Directors, the directors present thereat may
adjourn the meeting from time to time, without notice other than announcement at
the meeting, until a quorum shall be present.

     Section 9. Unless otherwise restricted by the certificate of incorporation
or these by-laws, any action required or permitted to be taken at any meeting of
the Board of Directors or of any committee thereof may be taken without a
meeting, if all members of the board or committee, as the case may be, consent
thereto in writing, and the writing or writings are filed with the minutes of
proceedings of the board or committee.

                             COMMITTEES OF DIRECTORS

     Section 10. The Board of Directors may, by resolution passed by a majority
of the whole board, designate one or more committees,

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each committee to consist of two or more of the directors of the corporation.
The board may designate one or more directors as alternate members of any
committee, who may replace any absent or disqualified member at any meeting of
the committee. Any such committee, to the extent provided in the resolution,
shall have and may exercise the powers of the Board of Directors in the
management of the business and affairs of the corporation, and may authorize the
seal of the corporation to be affixed to all papers which may require it;
provided, however, that in the absence or disqualification of any member of such
committee or committees, the member or members thereof present at any meeting
and not disqualified from voting, whether or not he or they constitute a quorum,
may unanimously appoint another member of the Board of Directors to act at the
meeting in the place of any such absent or disqualified member. Such committee
or committees shall have such name or names as may be determined from time to
time by resolution adopted by the Board of Directors.

     Section 11. Each committee shall keep regular minutes of its meetings and
report the same to the Board of Directors when required.

                            COMPENSATION OF DIRECTORS

     Section 12. The directors may be paid their expenses, if any, of attendance
at each meeting of the Board of Directors and may be paid a fixed sum for
attendance at each meeting of the Board of Directors or a stated salary as
director. No such payment shall

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preclude any director from serving the corporation in any other capacity and
receiving compensation therefor. Members of special or standing committees may
be allowed like compensation for attending committee meetings.

                                   ARTICLE IV

                                     NOTICES

     Section 1. Whenever, under the provisions of the statutes or of the
certificate of incorporation or of these by-laws, notice is required to be given
to any director or stockholder, it shall not be construed by mean personal
notice, but such notice may be given in writing, by mail, addressed to such
director or stockholder, at his address as it appears on the records of the
corporation, with postage thereon prepaid, and such notice shall be deemed to be
given at the time when the same shall be deposited in the United States mail.
Notice to directors may also be given by telegram.

     Section 2. The Board of Directors at its first meeting after each annual
meeting of stockholders must choose a president, one or more vice presidents, a
secretary and a treasurer.

     Section 3. The Board of Directors may appoint such other officers and
agents as it shall deem necessary who shall hold their offices for such terms
and shall exercise such powers and perform such duties as shall be determined
from time to time by the board.

     Section 4. The salaries of all officers and agents of the corporation shall
be fixed by the board of directors.

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     Section 5. The officers of the corporation shall hold office until their
successors are chosen and qualify. Any officer elected or appointed by the Board
of Directors may be removed at any time by the affirmative vote of a majority of
the Board of Directors. Any vacancy occurring in any office of the corporation
shall be filled by the Board of Directors.

                                  THE PRESIDENT

     Section 6. The president shall be the chief executive officer of the
corporation, shall preside at all meetings of the stockholders and the Board of
Directors, shall have general and active management of the business of the
corporation and shall see that all orders and resolutions of the Board of
Directors are carried into effect.

     Section 7. He shall execute bonds, mortgages and other contracts requiring
a seal, under the seal of the corporation, except where required or permitted by
law to be otherwise signed and executed and except where the signing and
execution thereof shall be expressly delegated by the Board of Directors to some
other officer or agent of the corporation.

                               THE VICE PRESIDENTS

     Section 8. In the absence of the president or in the event of his inability
or refusal to act, the vice president (or in the event there be more than one
vice president, the vice presidents in the order designated, or in the absence
of any designation, then in

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the order of their election) shall perform the duties of the president, and when
so acting, shall have all the powers of and be subject to all the restrictions
upon the president. The vice presidents shall perform such other duties and have
such other powers as the Board of Directors may from time to time prescribe.

                    THE SECRETARY AND ASSISTANT SECRETARIES

     Section 9. The secretary shall attend all meetings of the Board of
Directors and all meetings of the stockholders and record all the proceedings of
the meetings of the corporation and of the Board of Directors in a book to be
kept for that purpose and shall perform like duties for the standing committees
when required. He/she shall give, or cause to be given. notice of all meetings
of the stockholders and special meetings of the Board of Directors, and shall
perform such other duties as may be prescribed by the Board of Directors or
president, under whose supervision he/she shall be. He/she shall have custody of
the corporate seal of the corporation and he, or an assistant secretary, shall
have authority to affix the same to any instrument requiring it and when so
affixed, it may be attested by his signature or by the signature of such
assistant secretary. The Board of Directors may give general authority to any
other officer to affix the seal of the corporation and to attest the affixing by
his/her signature.

     Section 10. The assistant secretary, or if there be more than one, the
assistant secretaries in the order determined by the Board of Directors (or if
there be no such determination, then in the

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order of their election), shall, in the absence of the secretary or in the event
of his/her inability or refusal to act, perform the duties and exercise the
powers of the secretary and shall perform such other duties and have such other
powers as the Board of Directors may from time to time prescribe.

                     THE TREASURER AND ASSISTANT TREASURERS

     Section 11. The treasurer shall have the custody of the corporate funds and
securities and shall keep full and accurate accounts of receipts and
disbursements in books belonging to the corporation and shall deposit all moneys
and other valuable effects in the name and to the credit of the corporation in
such depositories as may be designated by the Board of Directors.

     Section 12. He/she shall disburse the funds of the corporation as may be
ordered by the Board of Directors, taking proper vouchers for such
disbursements, and shall render to the president and the Board of Directors, at
its regular meetings, or when the Board of Directors so requires, an account of
all his/her transactions as treasurer and of the financial condition of the
corporation.

     Section 13. If required by the Board of Directors, he/she shall give the
corporation a bond (which shall be renewed every six years) in such sum and with
such surety or sureties as shall be satisfactory to the Board of Directors for
the faithful performance of the duties of his office and for the restoration to
the corporation, in case of his/her death, resignation, retirement or

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removal from office, of all books, papers, vouchers, money and other property of
whatever kind in his/her possession or under his control belonging to the
corporation.

     Section 14. The assistant treasurer, or if there shall be more than one,
the assistant treasurers in the order determined by the Board of Directors (or
if there be no such determination, then in the order of their election), shall,
in the absence of the treasurer or in the event of his/her inability or refusal
to act, perform the duties and execise the powers of the treasurer and shall
perform such other duties and have such other powers as the Board of Directors
may from time to time prescribe.

                                   ARTICLE VI

                             CERTIFICATES OF STOCK

     Section 1. Every holder of stock in the corporation shall be entitled to
have a certificate, signed by, or in the name of the corporation by, the
chairman or vice chairman of the Board of Directors or the president or a vice
president and the treasurer or an assistant treasurer, or the secretary or an
assistant secretary of the corporation, certifying the number of shares owned by
him in the corporation.

     Section 2. Where a certificate is countersigned (1) by a transfer agent
other than the corporation or its employee, or, (2) by a registrar other than
the corporation or its employee, the signatures of the officers of the
corporation may be facsimiles.

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In case any officer who has signed or whose facsimile signature has been placed
upon a certificate shall have ceased to be such officer before such certificate
is issued, it may be issued by the corporation with the same effect as if he/she
were such officer at the date of issue.

                                LOST CERTIFICATES

     Section 3. The Board of Directors may direct a new certificate or
certificates to be issued in place of any certificate or certificates
theretofore issued by the corporation alleged to have been lost, stolen or
destroyed, upon the making of an affidavit of that fact by the person claiming
the certificate of stock to be lost, stolen or destroyed. When authorizing such
issue of a new certificate or certificates, the Board of Directors may, in its
discretion and as a condition precedent to the issuance thereof, require the
owner of such lost, stolen or destroyed certificate or certificates, or his
legal representative, to advertise the same in such manner as it shall require
and/or to give the corporation a bond in such sum as it may direct as indemnity
against any claim that may be made against the corporation with respect to the
certificate alleged to have been lost, stolen or destroyed.

                               TRANSFERS OF STOCK

     Section 4. Upon surrender to the corporation or the transfer agent of the
corporation of a certificate for shares duly endorsed

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or accompanied by proper evidence of succession, assignment or authority to
transfer, it shall be the duty of the corporation to issue a new certificate to
the person entitled thereto, cancel the old certificate and record the
transaction upon its books.

                               FIXING RECORD DATE

     Section 5. In order that the corporation may determine the stockholders
entitled to notice of or to vote at any meeting of stockholders or any
adjournment thereof, or to express consent to corporate action in writing
without a meeting, or entitled to receive payment of any dividend or other
distribution or allotment of any rights, or entitled to exercise any rights in
respect of any change, conversion or exchange of stock or for the purpose of any
other lawful action, the Board of Directors may fix, in advance, a record date,
which shall not be more than sixty nor less than ten days before the date of
such meeting, nor more than sixty days prior to any other action. A
determination of stockholders of record entitled to notice of or to vote at a
meeting of stockholders shall apply to any adjournment of the meeting; provided,
however, that the Board of Directors may fix a new record date for the adjourned
meeting.

                             REGISTERED STOCKHOLDERS

     Section 6. The corporation shall be entitled to recognize the exclusive
right of a person registered on its books as the owner of shares to receive
dividends, and to vote as such owner, and to hold

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liable for calls and assessments a person registered on its books as the owner
of shares, and shall not be bound to recognize any equitable or other claim to
interest in such share or shares on the part of any other person, whether or not
it shall have express or other notice thereof, except as otherwise provided by
the laws of Delaware.

                                   ARTICLE VII

                               GENERAL PROVISIONS

                                   DIVIDENDS

     Section 1. Dividends upon the capital stock of the corporation, subject to
the provisions of the certificate of incorporation, if any, may be declared by
the Board of Directors at any regular or special meeting, pursuant to law.
Dividends may be paid in cash, in property, or in shares of the capital stock,
subject to the provisions of the certificate of incorporation.

     Section 2. Before payment of any dividend, there may be set aside out of
any funds of the corporation available for dividends such sum or sums as the
directors from time to time, in their absolute discretion, think proper as a
reserve or reserves to meet contingencies, or for equalizing dividends, or for
repairing or maintaining any property of the corporation, or for such other
purpose as the directors shall think conducive to the interest of the
corporation, and the directors may modify or abolish any such reserve in the
manner in which it was created.

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                                ANNUAL STATEMENT

     Section 3. The Board of Directors shall present at each annual meeting, and
at any special meeting of the stockholders when called for by vote of the
stockholders, a full and clear statement of the business and condition of the
corporation.

                                     CHECKS

     Section 4. All checks or demands for money and notes of the corporation
shall be signed by such officer or officers or such other person or persons as
the Board of Directors may from time to time designate.

                                   FISCAL YEAR

     Section 5. The fiscal year of the corporation shall be fixed by resolution
of the Board of Directors.

                                      SEAL

     Section 6. The corporate seal shall have inscribed thereon the name of the
corporation, the year of its organization and the words "Corporate Seal,
Delaware". The seal may be used by causing it or a facsimile thereof to be
impressed or affixed or reproduced or otherwise.

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                                  ARTICLE VIII

                                   AMENDMENTS

     Section 1. These by-laws may be altered or repealed at any regular meeting
of the stockholders or of the Board of Directors or at any special meeting of
the stockholders or of the Board of Directors if notice of such alteration or
repeal be contained in the notice of such special meeting.

                                   ARTICLE IX

                   INDEMNIFICATION OF OFFICERS AND DIRECTORS

     Section 1. This corporation shall indemnify and hold harmless all of its
officers and directors, and any of its other agents and employees specifically
designated by the Board of Directors, or the corporate president, in connection
with any threatened, pending or contemplated action, suit, proceeding, whether
civil, criminal, administrative or investigative, by reason of their
relationship to the corporation against expenses, judgments, fines, amounts paid
in settlement or otherwise reasonably incurred, to the extent covered by Section
145, Delaware General Corporation Law, under the circumstances and pursuant to
the procedures therein set forth.

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