Exhibit 5

                                                                January 18, 2002

General Dynamics Corporation
3190 Fairview Park Drive
Falls Church, Virginia  22042-4523

Ladies and Gentlemen:

        We have acted as counsel to General Dynamics Corporation, a Delaware
corporation (the "Company"), and to the subsidiaries of the Company named in
Schedule I hereto (the "Guarantors") in connection with the Registration
Statement on Form S-4 (the "Registration Statement") filed by the Company and
the Guarantors with the Securities and Exchange Commission (the "Commission")
under the Securities Act of 1933, as amended, relating to the issuance by the
Company of $500,000,000 aggregate principal amount of Floating Rate Notes due
2004 (the "Exchange Notes") and the issuance by the Guarantors of guarantees
(the "Guarantees") with respect to the Exchange Notes. The Exchange Notes and
the Guarantees will be issued under an indenture dated as of August 27, 2001
(the "Indenture"), among the Company, the Guarantors and The Bank of New York,
as Trustee (the "Trustee"), as supplemented by the First Supplemental Indenture
dated as of August 27, 2001 (the "First Supplemental Indenture"), among the
Company, the Guarantors and the Trustee. The Exchange Notes will be offered by
the Company in exchange for all outstanding $500,000,000 Floating Rate Notes due
2004 of the Company (the "Outstanding Notes").

        We have examined the Registration Statement, the Indenture, the First
Supplemental Indenture and the form of the Exchange Notes, which is set forth as
an exhibit to the Registration Statement. We also have examined the originals,
or duplicates or certified or conformed copies, of such records, agreements,
instruments and other documents and have made such other and further
investigations as we have deemed relevant and necessary in connection with the
opinions expressed herein. As to questions of fact material to this opinion, we
have relied upon certificates of officers and representatives of the Company and
the Guarantors.

        In rendering the opinions set forth below, we have assumed the
genuineness of all signatures, the legal capacity of natural persons, the
authenticity of all documents submitted to us as originals, the conformity to
original documents submitted to us as duplicates or certified or conformed
copies, and the authenticity of the originals of such latter documents. We also
have assumed that each of the Indenture and the First Supplemental Indenture is
the valid and legally binding obligation of the Trustee.

        Based upon the foregoing, and subject to the qualifications and
limitations stated herein, we are of the opinion that:

        1. When the Exchange Notes have been duly executed, authenticated,
issued and delivered in accordance with the provisions of the Indenture and the
First Supplemental





Indenture in exchange for the Outstanding Notes, the Exchange Notes will
constitute valid and legally binding obligations of the Company.

        2. When the Exchange Notes have been duly executed, authenticated,
issued and delivered in accordance with the provisions of the Indenture and the
First Supplemental Indenture in exchange for the Outstanding Notes, the
Guarantees will constitute valid and legally binding obligations of the
Guarantors.

        Our opinions set forth above are subject to the effects of (1)
bankruptcy, insolvency, fraudulent conveyance, reorganization, moratorium and
other similar laws relating to or affecting creditors' rights generally, (2)
general equitable principles (whether considered in a proceeding in equity or at
law), (3) the implied covenant of good faith and fair dealing and (4) public
policy.

        We do not express any opinion herein concerning any law other than the
Delaware General Corporation Law, the law of the State of Illinois and the
Federal law of the United States.

        We hereby consent to the filing of this letter as Exhibit 5 to the
Registration Statement and to the use of our name under the caption "Legal
Matters" in the Prospectus included in the Registration Statement.

                                                        Very truly yours,



                                                        /s/ Jenner & Block, LLC






                                   SCHEDULE I

                                   GUARANTORS

American Overseas Marine Corporation
Bath Iron Works Corporation
Electric Boat Corporation
General Dynamics Advanced Technology Systems, Inc.
General Dynamics Armament Systems, Inc.
General Dynamics Defense Systems, Inc.
General Dynamics Government Systems Corporation
General Dynamics Information Systems, Inc.
General Dynamics Land System Inc.
General Dynamics Ordnance and Tactical Systems, Inc.
Gulfstream Aerospace Corporation
Material Service Resources Company
National Steel and Shipbuilding Company