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Exhibit 5.1

Skadden, Arps, Slate, Meagher & Flom LLP
Four Times Square
New York, New York 10036

January 6, 2006

DRS Technologies, Inc.
5 Sylvan Way
Parsippany, New Jersey 07054

Re:

DRS Technologies, Inc.
REGISTRATION STATEMENT ON FORM S-3

Ladies and Gentlemen:

        We have acted as special counsel to DRS Technologies, Inc., a Delaware corporation (the "Company"), in connection with the Registration Statement on Form S-3 (the "Registration Statement"), to be filed on the date hereof by the Company with the Securities and Exchange Commission (the "Commission") under the Securities Act of 1933, as amended (the "Act"). The Registration Statement relates to the issuance and sale from time to time by the Company, pursuant to Rule 415 of the General Rules and Regulations promulgated under the Act, of the following securities of the Company: (i) senior debt securities or subordinated debt securities, which may be issued in one or more series (the "Debt Securities"), under one or more indentures relating to either senior debt securities or subordinated debt securities, as applicable (the "Indenture" or "Indentures"), proposed to be entered into between the Company and The Bank of New York (the "Trustee"); (ii) guarantees of the Debt Securities (the "Subsidiary Guarantees") by the subsidiaries of the Company incorporated or formed pursuant to the laws of the States of Delaware or New York and listed on Schedule I hereto (the "DE/NY Guarantors") and the subsidiaries of the Company listed on Schedule II hereto (the "Non-DE/NY Guarantors" and together with the DE/NY Guarantors, the "Subsidiary Guarantors"); (iii) shares of preferred stock, $10.00 par value per share, of the Company (the "Preferred Stock"), in one or more series; (iv) shares of common stock, $0.01 par value per share, of the Company ("Common Stock"); (v) warrants ("Warrants") to purchase Debt Securities, Preferred Stock, Common Stock or other securities of the Company as shall be designated by the Company at the time of the offering issued pursuant to one or more warrant agreements (each a "Warrant Agreement") proposed to be entered into between the Company and warrant agents to be named (the "Warrant Agent" or "Warrant Agents"); and (vi) such indeterminate amount of Debt Securities and number of shares of Preferred Stock or Common Stock as may be issued upon conversion, exchange or exercise of any Debt Securities, Preferred Stock or Warrants, including such shares of Preferred Stock or Common Stock as may be issued pursuant to anti-dilution adjustments, in amounts, at prices and on terms to be determined at the time of offering (the "Indeterminate Stock"). The Debt Securities, Subsidiary Guarantees, Preferred Stock, Common Stock, Warrants and Indeterminate Stock are collectively referred to herein as the "Offered Securities."

        This opinion is being delivered in accordance with the requirements of Item 601(b)(5) of Regulation S-K under the Act.

        In connection with this opinion, we have examined originals or copies, certified or otherwise identified to our satisfaction, of:

(i)

the Registration Statement relating to the Offered Securities;



(ii)

(a) the Amended and Restated Certificate of Incorporation of the Company, as certified by the Secretary of State of Delaware (the "Certificate of Incorporation"), and (b) the By-laws of the Company, as currently in effect (the "By-laws");



(iii)

(a) the certificate of incorporation and the by-laws of each of the DE/NY Guarantors that are corporations, and (b) the certificate of formation and the limited liability company agreement

or operating agreement of each of the DE/NY Guarantors that are limited liability companies or limited partnerships, as applicable;

(iv)

the form of Senior Indenture between the Company and the Trustee, and the form of senior note included therein;



(v)

the form of Subordinated Indenture between the Company and the Trustee, and the form of subordinated note included therein;



(vi)

certain resolutions adopted by the Board of Directors of the Company (the "Board of Directors") relating to the registration of the Offered Securities and related matters; and



(vii)

certain resolutions adopted by the board of directors or managers, as applicable, of each of the DE/NY Guarantors relating to the registration of the Offered Debt Securities, Offered Subsidiary Guarantees and related matters.

        We have also examined originals or copies, certified or otherwise identified to our satisfaction, of such records of the Company and the Subsidiary Guarantors and such agreements, certificates of public officials, certificates of officers or other representatives of the Company, the Subsidiary Guarantors and others, and such other documents, certificates and records as we have deemed necessary or appropriate as a basis for the opinions set forth herein.

        In our examination, we have assumed the legal capacity of all natural persons, the genuineness of all signatures, the authenticity of all documents submitted to us as originals, the conformity to original documents of all documents submitted to us as electronic, certified, conformed, photostatic or facsimile copies and the authenticity of the originals of such latter documents. In making our examination of executed documents or documents to be executed, we have assumed that the parties thereto, other than the Company and the DE/NY Guarantors, had or will have the power, corporate or other, to enter into and perform all obligations thereunder. We have also assumed that each of the Non-DE/NY Guarantors has been duly organized and is validly existing in good standing under the laws of their respective jurisdiction of organization. As to any facts material to the opinions expressed herein which were not independently established or verified, we have relied upon oral or written statements and representations of officers and other representatives of the Company, the Subsidiary Guarantors and others.

        We have assumed that the Indentures and any supplemental indentures thereto and the Warrant Agreements will be duly authorized, executed and delivered by the Trustee and Warrant Agents, respectively, and that any Debt Securities or Warrants that may be issued will be manually signed or countersigned, as the case may be, by duly authorized officers of the Trustee or the Warrant Agents, respectively. In addition, we have also assumed that the terms of the Offered Debt Securities (as defined below), Offered Subsidiary Guarantees (as defined below) and Offered Warrants (as defined below) will have been established so as not to violate, conflict with or constitute a default under (i) any agreement or instrument to which the Company or the Subsidiary Guarantors or their properties are subject, (ii) any law, rule or regulation to which the Company or the Subsidiary Guarantors are subject, (iii) any judicial or regulatory order or decree of any governmental authority or (iv) any consent, approval, license, authorization or validation of, or filing, recording or registration with any governmental authority.

        Our opinions set forth herein are limited to Delaware corporate law and the laws of the State of New York that, in our experience, are normally applicable to transactions of the type contemplated by the Registration Statement and, to the extent that judicial or regulatory orders or decrees or consents, approvals, licenses, authorizations, validations, filings, recordings or registrations with governmental authorities are relevant, to those required under such laws (all of the foregoing being referred to as "Opined on Law"). We do not express any opinion with respect to the law of any jurisdiction other than Opined on Law or as to the effect of any such non-opined law on the opinions herein stated. The Offered Securities may be issued from time to time on a delayed or continuous basis, and this opinion is limited to the laws, including the rules and regulations, as in effect on the date hereof, which laws are subject to change with possible retroactive effect.

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        Based upon and subject to the foregoing and the limitations, qualifications, exceptions and assumptions set forth herein, we are of the opinion that:

1.

With respect to any series of Debt Securities (the "Offered Debt Securities"), when (i) the Registration Statement, as finally amended (including all necessary post-effective amendments), has become effective under the Act and the applicable Indenture has been qualified under the Trust Indenture Act of 1939, as amended; (ii) an appropriate prospectus supplement or term sheet with respect to the Offered Debt Securities has been prepared, delivered and filed in compliance with the Act and the applicable rules and regulations thereunder; (iii) if the Offered Debt Securities are to be sold pursuant to a firm commitment underwritten offering, the underwriting agreement with respect to the Offered Debt Securities has been duly authorized, executed and delivered by the Company and the other parties thereto; (iv) the Board of Directors, including any appropriate committee appointed thereby, and appropriate officers of the Company have taken all necessary corporate action to approve the issuance and terms of the Offered Debt Securities and related matters; (v) each Indenture and any supplemental indenture in respect of such Offered Debt Securities has been duly authorized, executed and delivered by each party thereto; (vi) the terms of the Offered Debt Securities and of their issuance and sale have been duly established in conformity with the applicable Indenture and any supplemental indenture to be entered into in connection with the issuance of such Offered Debt Securities so as not to violate any applicable law, the Certificate of Incorporation or By-laws or result in a default under or breach of any agreement or instrument binding upon the Company and so as to comply with any requirement or restriction imposed by any court or governmental body having jurisdiction over the Company; and (vii) the Offered Debt Securities have been duly executed and authenticated in accordance with the provisions of the applicable Indenture and any supplemental indenture to be entered into in connection with the issuance of such Offered Debt Securities and duly delivered to the purchasers thereof upon payment of the agreed-upon consideration therefor, the Offered Debt Securities (including any Debt Securities duly issued upon conversion, exchange or exercise of any Debt Securities, Preferred Stock or Warrants), when issued and sold in accordance with the applicable Indenture, any supplemental indenture to be entered into in connection with the issuance of such Debt Securities and the applicable underwriting agreement, if any, or any other duly authorized, executed and delivered valid and binding purchase or agency agreement, will be valid and binding obligations of the Company, enforceable against the Company in accordance with its respective terms, except to the extent that enforcement thereof may be limited by (a) bankruptcy, insolvency, reorganization, fraudulent conveyance, moratorium or other similar laws now or hereafter in effect relating to creditors' rights generally, (b) general principles of equity (regardless of whether enforceability is considered in a proceeding at law or in equity), (c) public policy considerations which may limit the rights of parties to obtain remedies, (d) the waivers of any usury defense contained in the Indentures which may be unenforceable, (e) requirements that a claim with respect to any Offered Debt Securities denominated in a currency, currency unit or composite currency other than United States dollars (or a judgment denominated other than in United States dollars in respect of such claim) be converted into United States dollars at a rate of exchange prevailing on a date determined pursuant to applicable law, and (f) governmental authority to limit, delay or prohibit the making of payments outside the United States or in foreign currencies, currency units or composite currencies.

2.

With respect to any series of Warrants (the "Offered Warrants"), when (i) the Registration Statement, as finally amended (including all necessary post-effective amendments), has become effective under the Act; (ii) an appropriate prospectus supplement or term sheet with respect to the Offered Warrants has been prepared, delivered and filed in compliance with the Act and the applicable rules and regulations thereunder; (iii) if the Offered Warrants are to be sold pursuant to a firm commitment underwritten offering, an underwriting agreement with respect to the Offered Warrants has been duly authorized, executed and delivered by the Company and the other parties thereto; (iv) the Board of Directors, including any appropriate committee appointed thereby, and appropriate officers of the Company have taken all necessary corporate action to approve the issuance and terms of the Offered Warrants and related matters; (v) the terms of the Offered Warrants and of their issuance and sale have been duly established in conformity with the applicable Warrant Agreement so as not to violate any applicable law, the Certificate of

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Incorporation or By-laws or result in a default under or breach of any agreement or instrument binding upon the Company and so as to comply with any requirement or restriction imposed by any court or governmental body having jurisdiction over the Company by the Company and the applicable Warrant Agent; and (vi) the Offered Warrants have been duly executed, delivered and countersigned in accordance with the provisions of the applicable Warrant Agreement and duly issued and sold in the applicable form to be filed as an exhibit to the Registration Statement or any amendment thereto and in the manner contemplated in the Registration Statement or any prospectus supplement or term sheet relating thereto, the Offered Warrants (including any Warrants duly issued upon conversion, exchange or exercise of any Debt Securities or Preferred Stock), when issued and sold in accordance with the applicable Warrant Agreement and the applicable underwriting agreement or any other duly authorized, executed and delivered valid and binding purchase or agency agreement, will be valid and binding obligations of the Company, enforceable against the Company in accordance with their respective terms, except to the extent that enforcement thereof may be limited by (a) bankruptcy, insolvency, reorganization, fraudulent conveyance, moratorium or other similar laws now or hereafter in effect relating to creditors' rights generally, (b) general principles of equity (regardless of whether enforceability is considered in a proceeding at law or in equity); and (c) public policy considerations which may limit the rights of parties to obtain remedies.

3.

With respect to the shares of any series of Preferred Stock (the "Offered Preferred Stock"), when (i) the Registration Statement, as finally amended (including all necessary post-effective amendments), has become effective under the Act; (ii) an appropriate prospectus supplement or term sheet with respect to the shares of the Offered Preferred Stock has been prepared, delivered and filed in compliance with the Act and the applicable rules and regulations thereunder; (iii) if the Offered Preferred Stock is to be sold pursuant to a firm commitment underwritten offering, the underwriting agreement with respect to the shares of the Offered Preferred Stock has been duly authorized, executed and delivered by the Company and the other parties thereto; (iv) the Board of Directors, including any appropriate committee appointed thereby, and appropriate officers of the Company have taken all necessary corporate action to approve the issuance and terms of the shares of the Offered Preferred Stock and related matters, including the adoption of a Certificate of Designation for the Offered Preferred Stock in accordance with the applicable provisions of the corporate laws of the State of Delaware (the "Certificate of Designation") in the form to be filed as an exhibit to the Registration Statement, any amendment thereto or any document incorporated by reference therein; (v) the filing of the Certificate of Designation with the Secretary of State of the State of Delaware has duly occurred; (vi) the terms of the Offered Preferred Stock and of their issuance and sale have been duly established in conformity with the Certificate of Incorporation, including the Certificate of Designation relating to the Offered Preferred Stock, and the By-laws of the Company so as not to violate any applicable law, the Certificate of Incorporation or By-laws or result in a default under or breach of any agreement or instrument binding upon the Company and so as to comply with any requirement or restriction imposed by any court or governmental body having jurisdiction over the Company; and (vii) certificates in the form required under Delaware corporate law representing the shares of the Offered Preferred Stock are duly executed, countersigned, registered and delivered upon payment of the agreed-upon consideration therefor, the shares of the Offered Preferred Stock (including any Preferred Stock duly issued upon conversion, exchange or exercise of any Debt Securities, Preferred Stock or Warrants), when issued or sold in accordance with the applicable underwriting agreement or any other duly authorized, executed and delivered valid and binding purchase or agency agreement, will be duly authorized, validly issued, fully paid and nonassessable, provided that the consideration therefor is not less than $10.00 per share of Preferred Stock.

4.

With respect to any offering of Common Stock by the Company (the "Offered Common Stock"), when (i) the Registration Statement, as finally amended (including all necessary post-effective amendments), has become effective under the Act; (ii) an appropriate prospectus supplement or term sheet with respect to the Offered Common Stock has been prepared, delivered and filed in compliance with the Act and the applicable rules and regulations thereunder; (iii) if the Offered Common Stock is to be sold pursuant to a firm commitment underwritten offering, the underwriting agreement with respect to the Offered Common Stock has been duly authorized,

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executed and delivered by the Company and the other parties thereto; (iv) the Board of Directors, including any appropriate committee appointed thereby, and appropriate officers of the Company have taken all necessary corporate action to approve the issuance of the Offered Common Stock and related matters; (v) the terms of the issuance and sale of the Offered Common Stock have been duly established in conformity with the Certificate of Incorporation and By-laws so as not to violate any applicable law, the Certificate of Incorporation or By-laws or result in a default under or breach of any agreement or instrument binding upon the Company and so as to comply with any requirement or restriction imposed by any court or governmental body having jurisdiction over the Company; and (vi) certificates in the form required under Delaware corporate law representing the shares of Offered Common Stock are duly executed, countersigned, registered and delivered upon payment of the agreed upon consideration therefor, the shares of Offered Common Stock (including any Common Stock duly issued upon conversion, exchange or exercise of any Debt Securities, Preferred Stock or Warrants), when issued and sold in accordance with the applicable underwriting agreement with respect to the Offered Common Stock or any other duly authorized, executed and delivered valid and binding purchase or agency agreement, will be duly authorized, validly issued, fully paid and nonassessable, provided that the consideration therefor is not less than $0.01 per share of Common Stock.

5.

With respect to any Subsidiary Guarantee of Offered Debt Securities offered by any Subsidiary Guarantor (the "Offered Subsidiary Guarantee"), when (i) the Registration Statement, as finally amended (including all necessary post-effective amendments), has become effective under the Act and the applicable Indenture has been qualified under the Trust Indenture Act of 1939, as amended; (ii) an appropriate prospectus supplement or term sheet with respect to the Offered Subsidiary Guarantee has been prepared, delivered and filed in compliance with the Act and the applicable rules and regulations thereunder; (iii) if the Offered Subsidiary Guarantee is to be issued pursuant to a firm commitment underwritten offering, the underwriting agreement with respect to the Offered Subsidiary Guarantee has been duly authorized, executed and delivered by the such Subsidiary Guarantor and the other parties thereto; (iv) all necessary corporate action, including any required action by such Subsidiary Guarantor's board of directors or managers, as applicable, or any authorized committee thereof, or other action has been taken by such Subsidiary Guarantor to approve the issuance and terms of the Offered Subsidiary Guarantee and related matters; (v) each Indenture and any supplemental indenture in respect of such Offered Subsidiary Guarantee has been duly authorized, executed and delivered by each party thereto; (vi) the terms of the Offered Subsidiary Guarantee and of its issuance and sale have been duly established in conformity with the applicable Indenture and any supplemental indenture to be entered into in connection with the issuance of such Offered Subsidiary Guarantee so as not to violate any applicable law or the organizational or governing documents of such Subsidiary Guarantor or result in a default under or breach of any agreement or instrument binding upon such Subsidiary Guarantor and so as to comply with any requirement or restriction imposed by any court or governmental body having jurisdiction over such Subsidiary Guarantor; and (vii) the Offered Subsidiary Guarantee has been duly executed, delivered and countersigned in accordance with the provisions of the applicable Indenture and any supplemental indenture to be entered into in connection with the issuance of such Offered Subsidiary Guarantee and duly issued in accordance with the applicable Indenture, any supplemental indenture to be entered into in connection with the issuance of such Offered Subsidiary Guarantee and the applicable underwriting agreement, if any, or any other duly authorized, executed and delivered valid and binding purchase or agency agreement, will be valid and binding obligations of the such Subsidiary Guarantor, enforceable against such Subsidiary Guarantor in accordance with its respective terms, except to the extent that enforcement thereof may be limited by (a) bankruptcy, insolvency, reorganization, fraudulent conveyance, moratorium or other similar laws now or hereafter in effect relating to creditors' rights generally, (b) general principles of equity (regardless of whether enforceability is considered in a proceeding at law or in equity), and (c) public policy considerations which may limit the rights of parties to obtain remedies.

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        We hereby consent to the filing of this opinion with the Commission as an exhibit to the Registration Statement. We also hereby consent to the use of our name under the heading "Legal Matters" in the prospectus which forms a part of the Registration Statement. In giving this consent, we do not thereby admit that we are within the category of persons whose consent is required under Section 7 of the Act or the rules and regulations of the Commission promulgated thereunder. This opinion is expressed as of the date hereof unless otherwise expressly stated, and we disclaim any undertaking to advise you of any subsequent changes in the facts stated or assumed herein or of any subsequent changes in applicable laws.

Very truly yours,

/s/ Skadden, Arps, Slate, Meagher & Flom LLP

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SCHEDULE I
DE/NY SUBSIDIARY GUARANTORS

NAI Technologies, Inc.

DRS Electronic Systems, Inc.

DRS Surveillance Support Systems, Inc.

DRS Technical Services, Inc.

DRS Power & Control Technologies, Inc.

DRS Electric Power Technologies, Inc.

DRS Power Technology, Inc.

DRS Systems Management Corporation

DRS Optronics, Inc.

DRS Sensors & Targeting Systems, Inc.

DRS FPA, Inc.

DRS Infrared Technologies, L.P.

DRS Unmanned Technologies, Inc.

DRS Data & Imaging Systems, Inc.

DRS Technologies Canada, Inc.

DRS Communications Company LLC

DRS Systems, Inc.

Night Vision Equipment Co., Inc.

DRS International, Inc.

Integrated Defense Technologies, Inc.

DRS Test & Energy Management, Inc.

DRS EW & Network Systems, Inc.

DRS Signal Solutions, Inc.

DRS Codem Systems, Inc.

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SCHEDULE II
NON-DE/NY SUBSIDIARY GUARANTORS

DRS Tactical Systems Global Services, Inc.

DRS Tactical Systems, Inc.

DRS Engineering Development Labs, Inc.

DRS Signal Technologies, Inc.

DRS Signal Recording Technologies, Inc.

Tech Sym Corporation

DRS Training & Control Systems, Inc.

Maxco, Inc.

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SCHEDULE I DE/NY SUBSIDIARY GUARANTORS
SCHEDULE II NON-DE/NY SUBSIDIARY GUARANTORS