THIS WARRANT AND THE SHARES  ISSUABLE  HEREUNDER  HAVE NOT BEEN  REGISTERED
UNDER THE SECURITIES ACT OF 1933 OR APPLICABLE STATE SECURITIES LAWS AND MAY NOT
BE SOLD, TRANSFERRED OR ASSIGNED UNLESS IT IS SO REGISTERED OR AN EXEMPTION FROM
REGISTRATION IS AVAILABLE UNDER SAID ACT AND LAWS.


                               TELOS CORPORATION
                             COMMON STOCK PURCHASE
                                SERIES D WARRANT
     This certifies  that,  for value  received,  Foreign & Colonial  Enterprise
Trust PLC, c/o Berkeley Square House,  Berkeley Square, London W1X 5PA, England,
is  entitled  to  purchase  and  receive  from  Telos  Corporation,  a  Maryland
corporation (the "Company"),  during the period hereinafter provided,  1,200,000
fully paid and  non-assessable  shares of the $.01 par value common voting stock
of the Company (the "Common  Stock") upon  surrender  hereof,  at the  principal
office of the  Company in Ashburn,  Virginia,  and  simultaneous  payment of the
purchase  price of $.01 for each share of the Common  Stock so to be  purchased;
such number of shares and such purchase price per share being subject,  however,
to adjustment as hereinafter provided. The purchase price per share, as adjusted
from time to time, is hereinafter referred to as the "Purchase Price."

     This Warrant shall be exercisable  commencing November 20, 1998, that being
the issuance date of that certain  Series D Senior  Subordinated  Unsecured Note
Due  October 1,  2000,  issued by the  Company  to the  Holder of this  Series D
Warrant, and shall expire on October 1, 2000.

1.       Purchase Price Adjustments.

     a. General.  The Purchase Price shall be subject to adjustment from time to
time pursuant to the terms of this Section 1.

     b.  Recapitalizations.  If outstanding shares of the Company's Common Stock
shall be  subdivided  into a greater  number of shares or a  dividend  in Common
Stock shall be paid in respect of Common  Stock,  the  Purchase  Price in effect
immediately  prior to such  subdivision  or at the record date of such  dividend
shall  simultaneously  with the effectiveness of such subdivision or immediately
after  the  record  date  of  such  dividend  be  proportionately   reduced.  If
outstanding  shares of Common Stock shall be combined  into a smaller  number of
shares,  the  Purchase  Price in effect  immediately  prior to such  combination
shall,   simultaneously   with  the  effectiveness  of  such   combination,   be
proportionately increased.

     c.  Mergers,  etc.  If there  shall  occur any  capital  reorganization  or
reclassification of the Company's Common Stock (other than a change in par value
or a subdivision or combination as provided for in Subsection 1b, above), or any
consolidation  or merger of the Company with or into another  corporation,  or a
transfer of all or substantially all of the assets of the Company, then, as part
of any such reorganization, reclassification,  consolidation, merger or sale, as
the case may be, lawful provision shall be made so that the registered Holder of
this Warrant shall have the right thereafter to receive upon the exercise hereof
the kind and amount of shares of stock or other  securities  or  property  which
such registered Holder would have been entitled to receive if, immediately prior
to any such reorganization, reclassification,  consolidation, merger or sale, as
the case may be, such registered  Holder had held the number of shares of Common
Stock which were then purchasable upon the exercise of this Warrant. In any such
case,  appropriate  adjustment  (as  reasonably  determined in good faith by the
Board of  Directors  of the  Company)  shall be made in the  application  of the
provisions set forth herein with respect to the rights and interests  thereafter
of the registered Holder of this Warrant,  such that the provisions set forth in
this Section 1 (including  provisions with respect to adjustment of the Purchase
Price) shall thereafter be applicable,  as nearly as is reasonably  practicable,
in relation to any shares of stock or other  securities  or property  thereafter
deliverable upon the exercise of this Warrant.

     d.  Certificate of  Adjustment.  When any adjustment is required to be made
pursuant to this Section 1, the Company shall  promptly  mail to the  registered
Holder a certificate  setting forth the Purchase Price after such adjustment and
setting forth a brief  statement of the facts  requiring such  adjustment.  Such
certificate  shall  also  set  forth  the  kind  and  amount  of  stock or other
securities or property into which this Warrant  shall be  exercisable  following
such adjustment.

     2. Registration Rights.
     a. Certain Definitions.  As used in this Warrant, the following terms shall
have the following respective meanings:

     "Commission"  means the  Securities and Exchange  Commission,  or any other
Federal agency at the time administering the Securities Act.

     "Common  Stock" means the common  stock,  $.01 par value per share,  of the
Company.

     "Exchange  Act" means the Securities  Exchange Act of 1934, as amended,  or
any similar  Federal  statute,  and the rules and  regulations of the Commission
issued under such Act, as they each may, from time to time, be in effect.

     "Registration  Statement"  means  a  registration  statement  filed  by the
Company  with the  Commission  for a public  offering  and sale of Common  Stock
(other  than a  registration  statement  on  Form  S-8 or  Form  S-4,  or  their
successors, or any other form for a similar limited purpose, or any registration
statement  covering  only  securities  proposed  to be  issued in  exchange  for
securities or assets of another corporation).

     "Registration Expenses" means the expenses described in Subsection e.

     "Registrable  Shares"  means the shares of Common  Stock issued or issuable
upon   exercise   of  this   Warrant   or  other   Series  D   Warrants   issued
contemporaneously;  provided,  however,  that  shares of Common  Stock which are
Registrable  Shares shall cease to be  Registrable  Shares upon any sale of such
Registrable  Shares  pursuant to a Registration  Statement or Rule 144 under the
Securities  Act.  Wherever  reference  is made in this  Warrant  to a request or
consent  of  holders  of  a  certain  percentage  of  Registrable   Shares,  the
determination  of such percentage  shall include shares of Common Stock issuable
upon exercise of the Warrant even if such exercise  conversion  has not yet been
effected.

     "Securities  Act" means the  Securities  Act of 1933,  as  amended,  or any
similar Federal statute,  and the rules and regulations of the Commission issued
under such Act, as they each may, from time to time, be in effect.

     "Stockholders"  means the  Holders  and any persons or entities to whom the
rights  granted  under  this  Warrant  are  transferred  by any  Holders,  their
successors or assigns pursuant to Section 4 hereof.

     b. Required Registrations.
     (1) At any time after the Company  becomes  eligible to file a Registration
Statement on Form S-3 (or any successor form relating to secondary offerings), a
Stockholder  or  Stockholders  holding  in the  aggregate  at  least  20% of the
Registrable  Shares  issued  pursuant  to the Series D Warrants  may request the
Company,  in writing,  to effect the registration on Form S-3 (or such successor
form), of Registrable Shares having an aggregate offering price of at least Five
Hundred  Thousand  Dollars  ($500,000)  (based on the then current public market
price).  Upon  receipt of any such  request,  the Company  shall  promptly  give
written  notice  of  such  proposed  registration  to  all  Stockholders.   Such
Stockholders  shall  have the right,  by giving  written  notice to the  Company
within 30 days after the Company provides its notice,  to elect to have included
in such registration  such of their Registrable  Shares as such Stockholders may
request in such notice of election;  provided that if the  underwriter  (if any)
managing the offering determines that, because of marketing factors,  all of the
Registrable  Shares  requested to be registered by all  Stockholders  may not be
included in the offering,  then all Stockholders who have requested registration
shall  participate  in the  registration  pro  rata  based  upon the  number  of
Registrable Shares which they have requested to be so registered. Thereupon, the
Company shall, as expeditiously as possible,  use its best efforts to effect the
registration  on Form S-3 (or such  successor  form) of all  Registrable  Shares
which the Company has been requested to so register.

     (2) The Company  shall not be required to effect more than 3  registrations
pursuant to Subparagraph  (1) above, nor shall the Company be required to effect
a registration  pursuant to  Subparagraph  (1) above within six months after the
effective date of any other Registration Statement of the Company (other than on
Form S-3, or S-8, or any successor form).

     (3) If at the time of any request to register  Registrable  Shares pursuant
to this Subsection b, the Company is engaged or has fixed plans to engage within
30 days of the time of the request in a registered  public  offering as to which
the Stockholders may include  Registrable  Shares pursuant to Subsection c or is
engaged in any other  activity  which,  in the good faith  determination  of the
Company's  Board of  Directors,  would be  adversely  affected by the  requested
registration to the material  detriment of the Company,  then the Company may at
its option direct that such request be delayed for a period not in excess of six
months from the effective date of such offering or the date of  commencement  of
such other material activity, as the case may be.

     c. Incidental Registration.

     (1) Whenever the Company  proposes to file a Registration  Statement (other
than  pursuant to  Subsection  b(1)) at any time and from time to time, it will,
prior to such filing,  give written notice to all  Stockholders of its intention
to do so and, upon the written  request of a Stockholder or  Stockholders  given
within 20 days after the Company provides such notice (which request shall state
the intended  method of disposition  of such  Registrable  Shares),  the Company
shall use its best efforts to cause all Registrable Shares which the Company has
been requested by such  Stockholder or Stockholders to register to be registered
under the Securities  Act to the extent  necessary to permit their sale or other
disposition in accordance with the intended methods of distribution specified in
the request of such Stockholder or Stockholders; provided that the Company shall
have the right to postpone or withdraw  any  registration  effected  pursuant to
this Subsection c without obligation to any Stockholder.

     (2) In connection with any  registration  under this Subsection c involving
an  underwriting,  the Company shall not be required to include any  Registrable
Shares in such  registration  unless the holders thereof accept the terms of the
underwriting as agreed upon between the Company and the underwriters selected by
it (provided that such terms must be consistent  with this  Warrant).  If in the
opinion of the  managing  underwriter  it is  appropriate  because of  marketing
factors  to limit  the  number  of  Registrable  Shares  to be  included  in the
offering, then the Company shall be required to include in the registration only
that  number of  Registrable  Shares,  if any,  which the  managing  underwriter
believes should be included therein.  If the number of Registrable  Shares to be
included in the offering in accordance with the foregoing is less than the total
number of shares which the holders of  Registrable  Shares have  requested to be
included, then the holders of Registrable Shares who have requested registration
and other  holders of securities  entitled to include them in such  registration
shall  participate in the registration pro rata based upon their total ownership
of shares of Common Stock (giving effect to the conversion  into Common Stock of
all securities convertible  thereinto).  If any holder would thus be entitled to
include more securities than such holder requested to be registered,  the excess
shall be  allocated  among  other  requesting  holders  pro  rata in the  manner
described in the preceding sentence.

     d. Registration Procedures.  If and whenever the Company is required by the
provisions of this Warrant to use its best efforts to effect the registration of
any of the Registrable Shares under the Securities Act, the Company shall:

     (1) file with the Commission a Registration  Statement with respect to such
Registrable Shares and use its best efforts to cause that Registration Statement
to become and remain effective;

     (2) as  expeditiously  as possible prepare and file with the Commission any
amendments  and  supplements  to the  Registration  Statement and the prospectus
included  in the  Registration  Statement  as  may  be  necessary  to  keep  the
Registration Statement effective,  in the case of a firm commitment underwritten
public  offering,  until each  underwriter has completed the distribution of all
securities  purchased  by it and, in the case of any other  offering,  until the
earlier of the sale of all Registrable  Shares covered thereby or 120 days after
the effective date thereof;

     (3) as expeditiously  as possible furnish to each selling  Stockholder such
reasonable  numbers  of  copies  of  the  prospectus,  including  a  preliminary
prospectus,  in conformity with the requirements of the Securities Act, and such
other documents as the selling  Stockholder  may reasonably  request in order to
facilitate the public sale or other disposition of the Registrable  Shares owned
by the selling Stockholder; and

     (4) as  expeditiously  as  possible  use its best  efforts to  register  or
qualify the Registrable  Shares covered by the Registration  Statement under the
securities  or Blue Sky laws of such  states as the selling  Stockholders  shall
reasonably  request,  and do any and all  other  acts  and  things  that  may be
necessary or  desirable to enable the selling  Stockholders  to  consummate  the
public sale or other disposition in such states of the Registrable  Shares owned
by the selling  Stockholder;  provided,  however,  that the Company shall not be
required  in  connection  with this  Subparagraph  (4) to  qualify  as a foreign
corporation  or  execute  a  general  consent  to  service  of  process  in  any
jurisdiction.

     If the Company  has  delivered  preliminary  or final  prospectuses  to the
selling  Stockholders  and after  having  done so the  prospectus  is amended to
comply with the  requirements  of the Securities Act, the Company shall promptly
notify the selling  Stockholders  and, if  requested,  the selling  Stockholders
shall  immediately  cease  making  offers of  Registrable  Shares and return all
prospectuses  to the Company.  The Company  shall  promptly  provide the selling
Stockholders  with revised  prospectuses  and,  following receipt of the revised
prospectuses,  the selling Stockholders shall be free to resume making offers of
the Registrable Shares.

     e. Allocation of Expenses.  The Company will pay all Registration  Expenses
of  all  registrations  under  this  Warrant;  provided,   however,  that  if  a
registration  under Subsection b is withdrawn at the request of the Stockholders
requesting such registration  (other than as a result of information  concerning
the  business or financial  condition of the Company  which is made known to the
Stockholders after the date on which such registration was requested) and if the
requesting  Stockholders  elect  not to  have  such  registration  counted  as a
registration requested under Subection b, the requesting  Stockholders shall pay
the Registration  Expenses of such  registration pro rata in accordance with the
number of their Registrable Shares included in such  registration.  For purposes
of this Subsection e, the term  "Registration  Expenses" shall mean all expenses
incurred by the  Company in  complying  with this  Warrant,  including,  without
limitation,  all registration and filing fees,  exchange listing fees,  printing
expenses, fees and expenses of counsel for the Company and the fees and expenses
of one counsel  selected by the selling  Stockholders  to represent  the selling
Stockholders,  state Blue Sky fees and expenses,  and the expense of any special
audits  incident  to  or  required  by  any  such  registration,  but  excluding
underwriting discounts, selling commissions and the fees and expenses of selling
Stockholders'  own counsel  (other than the counsel  selected to  represent  all
selling Stockholders).
<PAGE>

    f.       Indemnification and Contribution.

     (1) In the event of any registration of any of the Registrable Shares under
the Securities Act pursuant to this Warrant, the Company will indemnify and hold
harmless  the  seller  of such  Registrable  Shares,  each  underwriter  of such
Registrable  Shares,  and each other person, if any, who controls such seller or
underwriter within the meaning of the Securities Act or the Exchange Act against
any losses,  claims,  damages or  liabilities,  joint or several,  to which such
seller,   underwriter  or  controlling  person  may  become  subject  under  the
Securities  Act,  the  Exchange  Act,  state  securities  or  Blue  Sky  laws or
otherwise, insofar as such losses, claims, damages or liabilities (or actions in
respect  thereof) arise out of or are based upon any untrue statement or alleged
untrue  statement of any material fact contained in any  Registration  Statement
under which such  Registrable  Shares were registered  under the Securities Act,
any preliminary  prospectus or final  prospectus  contained in the  Registration
Statement,  or any amendment or supplement to such  Registration  Statement,  or
arise out of or are based  upon the  omission  or  alleged  omission  to state a
material fact required to be stated  therein or necessary to make the statements
therein not misleading;  and the Company will reimburse such seller, underwriter
and each such controlling person for any legal or any other expenses  reasonably
incurred by such seller,  underwriter or controlling  person in connection  with
investigating or defending any such loss,  claim,  damage,  liability or action;
provided,  however,  that the Company will not be liable in any such case to the
extent that any such loss, claim,  damage or liability arises out of or is based
upon any untrue  statement  or  omission  made in such  Registration  Statement,
preliminary prospectus or final prospectus, or any such amendment or supplement,
in reliance upon and in conformity with information furnished to the Company, in
writing,  by or on behalf of such  seller,  underwriter  or  controlling  person
specifically for use in the preparation thereof.

     (2) In the event of any registration of any of the Registrable Shares under
the Securities Act pursuant to this Warrant,  each seller of Registrable Shares,
severally and not jointly, will indemnify and hold harmless the Company, each of
its directors  and officers and each  underwriter  (if any) and each person,  if
any, who controls the Company or any such underwriter  within the meaning of the
Securities  Act or the  Exchange  Act,  against any losses,  claims,  damages or
liabilities,  joint or  several,  to  which  the  Company,  such  directors  and
officers,  underwriter  or  controlling  person  may  become  subject  under the
Securities  Act,  Exchange Act, state  securities or Blue Sky laws or otherwise,
insofar as such losses,  claims,  damages or liabilities  (or actions in respect
thereof) arise out of or are based upon any untrue  statement of a material fact
contained in any Registration Statement under which such Registrable Shares were
registered  under  the  Securities  Act,  any  preliminary  prospectus  or final
prospectus  contained  in  the  Registration  Statement,  or  any  amendment  or
supplement to the Registration  Statement, or arise out of or are based upon any
omission to state a material fact required to be stated  therein or necessary to
make the  statements  therein not  misleading,  if the statement or omission was
made in reliance upon and in conformity with information relating to such seller
furnished in writing to the Company by or on behalf of such seller  specifically
for use in  connection  with the  preparation  of such  Registration  Statement,
prospectus,  amendment or supplement; provided, however, that the obligations of
such Stockholders  hereunder shall be limited to an amount equal to the proceeds
to  each  Stockholder  of  Registrable  Shares  sold  in  connection  with  such
registration.

     (3) Each party  entitled to  indemnification  under this  Subsection f (the
"Indemnified  Party")  shall  give  notice  to the  party  required  to  provide
indemnification (the "Indemnifying Party") promptly after such Indemnified Party
has actual knowledge of any claim as to which indemnity may be sought, and shall
permit the  Indemnifying  Party to assume  the  defense of any such claim or any
litigation  resulting  therefrom;  provided,  that counsel for the  Indemnifying
Party,  who shall  conduct  the  defense of such claim or  litigation,  shall be
approved by the  Indemnified  Party (whose  approval  shall not be  unreasonably
withheld); and, provided,  further, that the failure of any Indemnified Party to
give notice as provided herein shall not relieve the  Indemnifying  Party of its
obligations  under this Subsection f. The  Indemnified  Party may participate in
such defense at such party's expense;  provided,  however, that the Indemnifying
Party shall pay such expense if  representation of such Indemnified Party by the
counsel retained by the Indemnifying  Party would be inappropriate due to actual
or potential  differing  interests  between the Indemnified  Party and any other
party represented by such counsel in such proceeding.  No Indemnifying Party, in
the defense of any such claim or  litigation  shall,  except with the consent of
each  Indemnified  Party,  consent  to entry of any  judgment  or enter into any
settlement which does not include as an unconditional term thereof the giving by
the  claimant  or  plaintiff  to such  Indemnified  Party of a release  from all
liability in respect of such claim or litigation, and no Indemnified Party shall
consent to entry of any judgment or settle such claim or litigation  without the
prior written consent of the Indemnifying Party.
<PAGE>

     (4) In  order to  provide  for just  and  equitable  contribution  to joint
liability under the Securities Act in any case in which either (i) any holder of
Registrable  Shares  exercising  rights under this Warrant,  or any  controlling
person of any such holder,  makes a claim for  indemnification  pursuant to this
Subsection f but it is judicially  determined  (by the entry of a final judgment
or decree by a court of competent  jurisdiction  and the  expiration  of time to
appeal or the denial of the last right of appeal) that such  indemnification may
not be enforced in such case  notwithstanding  the fact that this  Subsection  f
provides  for  indemnification  in such  case,  or (ii)  contribution  under the
Securities  Act may be required on the part of any such selling  Stockholder  or
any such  controlling  person  in  circumstances  for which  indemnification  is
provided under this  Subsection f; then, in each such case, the Company and such
Stockholder  will  contribute  to  the  aggregate  losses,  claims,  damages  or
liabilities  to which they may be subject  (after  contribution  from others) in
such proportions so that such holder is responsible for the portion  represented
by the  percentage  that the public  offering  price of its  Registrable  shares
offered by the Registration  Statement bears to the public offering price of all
securities  offered  by  such  Registration   Statement,   and  the  Company  is
responsible  for the remaining  portion;  provided,  however,  that, in any such
case,  (A) no such holder will be required to contribute any amount in excess of
the  proceeds  to it of all  Registrable  Shares  sold  by it  pursuant  to such
Registration  Statement,  and (B) no  person  or  entity  guilty  of  fraudulent
misrepresentation,  within the meaning of Section 11(f) of the  Securities  Act,
shall be entitled to contribution from any person or entity who is not guilty of
such fraudulent misrepresentation.

     g. Indemnification with Respect to Underwritten Offering. In the event that
Registrable  Shares  are  sold  pursuant  to  a  Registration  Statement  in  an
underwritten offering pursuant to Subsection b, the Company agrees to enter into
an underwriting  agreement containing  customary  representations and warranties
with respect to the business and operations of an issuer of the securities being
registered  and  customary  covenants  and  agreements  to be  performed by such
issuer,  including  without  limitation  customary  provisions  with  respect to
indemnification by the Company of the underwriters of such offering.

     h. Information by Holder. Each Stockholder  including Registrable Shares in
any registration  shall furnish to the Company such  information  regarding such
Stockholder and the distribution proposed by such Stockholder as the Company may
reasonably  request in writing and as shall be required in  connection  with any
registration, qualification or compliance referred to in this Warrant.

     i. "Stand-Off"  Agreement".  Each Stockholder,  if requested by the Company
and the  managing  underwriter  of an offering by the Company of Common Stock or
other  securities of the Company  pursuant to a  Registration  Statement,  shall
agree not to sell publicly or otherwise  transfer or dispose of any  Registrable
Shares  or  other  securities  of the  Company  held by such  Stockholder  for a
specified  period of time (not to exceed 180 days)  following the effective date
of such Registration Statement; provided, that:

     (1) such  agreement  shall only apply to the first  Registration  Statement
covering  Common Stock to be sold on its behalf to the public in an underwritten
offering; and
     (2) all  Stockholders  holding not less than the number of shares of Common
Stock held by such Stockholder  (including  shares of Common Stock issuable upon
the conversion of Shares, or other convertible securities,  or upon the exercise
of options,  warrants or rights) and all officers  and  directors of the Company
enter into similar agreements.
     j. Termination.  All of the Company's  obligations to register  Registrable
Shares  under this Warrant  shall  terminate  on the tenth  anniversary  of this
Warrant.

     3. Exercise of Warrant.

     a. The Company  covenants  that it will at all times  maintain an available
and adequate  reserve of duly authorized but unissued share of its Common Stock,
free from  preemptive  rights,  sufficient  to effect the full  exercise of this
Warrant as herein provided, and that it will at all times maintain in full force
and effect an appropriate  permit of the Delaware  Commissioner  of Corporations
authorizing  the  issuance and sale by the Company of all shares of Common Stock
issuable upon exercise of this Warrant by the holder.

     The Company  covenants  that all shares of Common Stock  issuable  upon the
exercise of this Warrant will, upon issuance,  be validly issued, fully paid and
non-assessable,  and free from all taxes,  liens and charges with respect to the
issue thereof.

     The holder hereof may surrender  this Warrant for exchange at the principal
office of the Company.  Within a reasonable  time thereafter and without expense
(other than transfer taxes,  if any) to each holder,  the Company shall issue in
exchange  therefor,  in such  denominations  (of not less than 100  shares)  and
issued in such name or names as the holder shall  designate (if permitted by the
Federal  Securities laws and the relevant Blue Sky law(s),  as amended from time
to time), a new certificate or certificates dated the date hereof evidencing the
right to purchase  the same  aggregate  number of shares of Common  Stock as are
evidenced  hereby,  and otherwise  containing the same provisions and subject to
the same terms and conditions of this certificate.
<PAGE>

     Upon surrender of this Warrant at the office of the Company  accompanied by
payment of the  appropriate  Purchase  Price of the  Common  Stock in cash or as
otherwise  allowed  herein,  the Company shall  forthwith  cause to be executed,
issued and delivered to the holder of the Warrant a certificate or  certificates
for the  proper  number of shares of  common  stock or other  securities  of the
Company;  and the Company  covenants  that the  issuance of this  Warrant  shall
constitute full authority to those of its officers who are charged with the duty
of issuing  stock  certificates  to promptly  execute,  issue and deliver to the
holder of the Warrant the  necessary  certificate  for shares of Common Stock or
other securities of the Company required by such exercise.

     This  Warrant  may be  exercised  in  accordance  with its  terms  prior to
expiration  as a whole,  or from time to time in part.  In the event of  partial
exercise  of the  Warrant,  the  Company  shall,  in addition to delivery of the
securities  thereby  purchased,  deliver  to the  holder of the  Warrant,  a new
Warrant for the remaining shares then subject to the unexercised  portion of the
Warrant;  such new Warrant being dated the date hereof and otherwise  containing
the same  provisions and subject to the same  conditions and subject to the same
terms and conditions as this Warrant. Certificates for shares of Common Stock or
other  securities of the Company  issuable by reason of the exercise of Warrants
shall be dated and shall be  effective  as of the date of the  surrender  of the
Warrants  for  exercise  or  acceptance  of the  offering  of  shares  or  other
securities,  as the case may be,  and the  payment of the  appropriate  Purchase
Price,  notwithstanding any delay in the actual execution,  issuance or delivery
of the certificates or securities so purchased.

     This Warrant shall be  registered on the books of the Company,  which shall
be kept at its principal office for that purpose, and shall be transferable only
on said books by the holder hereof in person or by duly authorized attorney upon
surrender of this Warrant properly endorsed.

     b. This Warrant may be exercised by the holder hereof, in whole or in part,
by surrendering this Warrant at the principal office of the Company,  or at such
other office or agency as the Company may  designate,  accompanied by payment in
full,  in lawful money of the United  States,  of the Purchase  Price payable in
respect of the number of Warrant Shares purchased upon such exercise.

     c. The holder  hereof may,  at its option,  elect to pay some or all of the
Purchase  Price  payable upon an exercise of this Warrant by canceling a portion
of this Warrant  exercisable  for such number of Warrant Shares as is determined
by dividing  (i) the total  Purchase  Price  payable in respect of the number of
Warrant Shares being purchased upon such exercise by (ii) the excess of the Fair
Market Value per share of Common Stock as of the effective date of exercise (the
"Exercise  Date") over the Purchase  Price per share.  The Fair Market Value per
share of Common Stock shall be determined as follows:

     (1) If the Common Stock is listed on a national  securities  exchange,  the
NASDAQ  National  Market  System,  the  NASDAQ  system,  or  another  nationally
recognized  exchange or trading  system as of the Exercise Date, the Fair Market
Value per share of Common  Stock  shall be deemed to be the last  reported  sale
price per share of Common  Stock  thereon on the Exercise  Date;  or, if no such
price is reported on such date,  such price on the next  preceding  business day
(provided that if no such price is reported on the next preceding  business day,
the Fair Market Value per share of Common Stock shall be determined  pursuant to
Clause (2)).
     (2) If the Common  Stock is not listed on a national  securities  exchange,
the NASDAQ  National  Market  System,  the NASDAQ  system or another  nationally
recognized  exchange or trading  system as of the Exercise Date, the Fair Market
Value per share of Common  Stock shall be deemed to be the amount most  recently
determined  by the Board of  Directors  to  represent  the fair market value per
share of the Common Stock  (including  without  limitation a  determination  for
purposes of  granting  Common  Stock  options or issuing  Common  Stock under an
employee  benefit plan of the Company);  and, upon request of the holder hereof,
the Board of Directors (or a  representative  thereof) shall promptly notify the
holder   hereof  of  the  Fair   Market   Value  per  share  of  Common   Stock.
Notwithstanding  the  foregoing,  if the Board of Directors  has not made such a
determination within the three-month period prior to the Exercise Date, then (A)
the Fair  Market  Value per  share of  Common  Stock  shall be the  amount  next
determined  by the Board of  Directors  to  represent  the fair market value per
share of the Common Stock  (including  without  limitation a  determination  for
purposes of  granting  Common  Stock  options or issuing  Common  Stock under an
employee  benefit plan of the  Company),  (B) the Board of Directors  shall make
such a determination within 30 days of a request by the holder hereof that it do
so, and (C) the exercise of this Warrant pursuant to this Subsection 2c shall be
delayed until such determination is made.

     4.  Transfers of Rights.  This Warrant,  and the rights and  obligations of
each holder  hereof,  may be  assigned  by such  holder  hereof to any person or
entity to which  not fewer  than 100  Shares  (issued  or  issuable  under  this
Warrant) are  transferred by such holder hereof,  and such  transferee  shall be
deemed a  "holder  hereof"  for  purposes  of this  Warrant;  provided  that the
transferee provides written notice of such assignment to the Company.

     5.       General.

     a. Notices. All notices, requests, consents, and other communications under
this  Warrant  shall be in writing and shall be  delivered  by hand or mailed by
first class  certified or registered  mail,  return receipt  requested,  postage
prepaid:

     If to the Company,  at 19886 Ashburn Road,  Ashburn,  VA 20147,  Attention:
President,  or at such other address or addresses as may have been  furnished in
writing  by the  Company  to the  Holders,  with a copy to the  Chief  Financial
Officer and General Counsel; or

     If to a holder  hereof,  at his or its address set forth above,  or at such
other address or addresses as may have been  furnished to the Company in writing
by such holder hereof.
                         
     Notices  provided  in  accordance  with  this  Section  5 shall  be  deemed
delivered upon personal delivery or two business days after deposit in the mail.

     b.  Entire  Agreement.  This  Warrant  embodies  the entire  agreement  and
understanding  between the parties  hereto  with  respect to the subject  matter
hereof and supersedes all prior agreements and  understandings  relating to such
subject matter.

     c. Amendments and Waivers.  Any term of this Warrant may be amended and the
observance of any term of this Warrant may be waived  (either  generally or in a
particular instance and either retroactively or prospectively), with the written
consent  of the  Company  and the  holders  of at least  90% of the  Registrable
Shares;  provided,  that this  Warrant  may be amended  with the  consent of the
holders of less than all  Registrable  Shares only in a manner which affects all
Registrable Shares in the same fashion. No waivers of or exceptions to any term,
condition or provision of this Warrant,  in any one or more instances,  shall be
deemed to be, or construed as, a further or continuing  waiver of any such term,
condition or provision.

     d. Fractional  Shares.  The Company shall not be required upon the exercise
of this Warrant to issue any  fractional  shares,  but shall make an  adjustment
therefor  in cash on the  basis of the Fair  Market  Value  per  share of Common
Stock, as determined in good faith by the Board of Directors or as quoted if the
Common Stock is publicly traded on the day the Warrant was exercised.

Executed in Ashburn, Virginia as of the 20th day of November, 1998.

 
                                                               TELOS CORPORATION



                                         By:/s/            William L.P. Brownley
                                                           William L.P. Brownley
                                              Vice President and General Counsel



[SEAL]

Attest: /s/ Gerald D. Calhoun, Secretary                                        
            Gerald D. Calhoun, Secretary