Exhibit 5.1

January 27, 2022

Tailwind Two Acquisition Corp.

150 Greenwich Street, 29th Floor

New York, New York 10006

Ladies and Gentlemen:

We have acted as special legal counsel to Tailwind Two Acquisition Corp., a Cayman Islands exempted company (“Tailwind Two”), in connection with the Registration Statement on Form S-4, initially filed with the U.S. Securities and Exchange Commission (the “Commission”) on November 26, 2021 pursuant to the Securities Act of 1933, as amended (the “Act”) (such Registration Statement, as the same may be amended or supplemented, is hereafter referred to as the “Registration Statement”), relating to the Agreement and Plan of Merger, dated October 28, 2021 (as may be amended, supplemented or otherwise modified from time to time, the “Business Combination Agreement”), by and among Tailwind Two, Titan Merger Sub, Inc., a Delaware corporation (“Merger Sub”), and Terran Orbital Corporation, a Delaware corporation (“Terran Orbital”). Pursuant to the Business Combination Agreement, Tailwind Two will change its jurisdiction of incorporation from the Cayman Islands to the State of Delaware (the “Domestication”) by effecting a deregistration under Part XII of the Cayman Islands Companies Act (As Revised) and domesticate as a Delaware corporation in accordance with Section 388 of the General Corporation Law of the State of Delaware (the “DGCL”) by filing a certificate of corporate domestication simultaneously with a certificate of incorporation, in each case in respect of Tailwind Two with the Secretary of State of the State of Delaware (the “Delaware Secretary of State”). The Domestication is subject to the approval of the shareholders of Tailwind Two. We refer herein to Tailwind Two following effectiveness of the Domestication as “New Terran Orbital”.

Promptly following the consummation of the Domestication, Merger Sub will merge with and into Terran Orbital (the “Merger” and together with the Domestication and related transactions, the “Business Combination”), with Terran Orbital as the surviving company in the Merger and, after giving effect to the Merger, Terran Orbital will be a wholly-owned subsidiary of Tailwind Two (the time that the Merger becomes effective being referred to as the “Effective Time”). In connection with the Domestication, on the date of closing prior to the Effective Time, (i) each issued and outstanding Class A ordinary share, par value $0.0001 per share, of Tailwind Two (the “Class A Ordinary Shares”) will convert automatically by operation of law, on a one-for-one basis, into shares of common stock, par value $0.0001 per share, of New Terran Orbital (the “New Terran Orbital Common Stock”); (ii) each issued and outstanding Class B ordinary share, par value $0.0001 per share, of Tailwind Two (the “Class B Ordinary Shares”) will convert automatically by operation of law, on a one-for-one basis, into shares of New Terran Orbital Common Stock; (iii) each issued and outstanding whole warrant of Tailwind Two (the “Warrants”) to purchase Class A Ordinary Shares will be converted automatically into a warrant to purchase one share of New Terran Orbital Common Stock at an exercise price of $11.50 per share on the terms and conditions set forth in that certain Warrant Agreement, dated as of March 9, 2021, by and among Tailwind Two and Continental Stock Transfer & Trust Company, as warrant agent (the “Warrant Agreement”); and (iv)  each issued and outstanding unit of Tailwind Two that has not been previously separated into the underlying Class A Ordinary Share and underlying one-third of one Warrant upon the request of the holder thereof, will be cancelled and will entitle the holder thereof to one share of New Terran Orbital Common Stock and one-third of one Warrant. Following the Domestication and in connection with the consummation of the Business Combination, New Terran Orbital will also issue shares of New Terran Orbital Common Stock to holders of securities of Terran Orbital in exchange for such securities (the “Rollover Holders”).

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Tailwind Two Acquisition Corp.

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This opinion is being rendered in connection with the registration under the above-referenced Registration Statement of (i) 182,738,883 shares of New Terran Orbital Common Stock, representing (a) 34,500,000 shares to be issued to the holders of Class A Ordinary Shares (including those currently held in the form of units of Tailwind Two), (b) 8,625,000 shares to be issued to the holders of Class B Ordinary Shares, and (c) up to 139,613,883 shares to be issued to the Rollover Holders (the “Consideration Shares”), (ii) 19,300,000 shares of New Terran Orbital Common Stock to be issued upon the exercise of the Warrants (the “Warrants Shares”) and (iii)19,300,000 Warrants (including those currently held in the form of units of Tailwind Two).

In connection with the preparation of this opinion, we have, among other things, read:

For purposes of this opinion, we have assumed the authenticity of all documents submitted to us as originals, the conformity to the originals of all documents submitted to us as copies and the authenticity of the originals of all documents submitted to us as copies. We have also assumed the legal capacity of all natural persons, the genuineness of the signatures of persons signing all documents in connection with which this opinion is rendered, the authority of such persons signing on behalf of the parties thereto and the due authorization, execution and delivery of all documents by the parties thereto. We have not independently established or verified any facts relevant to the opinion expressed herein, but have relied upon statements and representations of officers and other representatives of Tailwind Two and others as to factual matters.

Subject to the assumptions, qualifications, exclusions and other limitations which are identified in this opinion, we advise you that:

Tailwind Two Acquisition Corp.

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In addition, in rendering the foregoing opinions we have assumed that:

Tailwind Two Acquisition Corp.

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Our opinions expressed above are subject to the qualifications that we express no opinion as to the applicability of, compliance with, or effect of (i) any bankruptcy, insolvency, reorganization, fraudulent transfer, fraudulent conveyance, moratorium or other similar law or judicially developed doctrine in this area (such as substantive consolidation or equitable subordination) affecting the enforcement of creditors’ rights generally, (ii) general principles of equity (regardless of whether enforcement is considered in a proceeding in equity or at law), (iii) an implied covenant of good faith and fair dealing, (iv) public policy considerations which may limit the rights of parties to obtain certain remedies, (v) any requirement that a claim with respect to any security denominated in other than U.S. dollars (or a judgment denominated in other than U.S. dollars in respect of such claim) be converted into U.S. dollars at a rate of exchange prevailing on a date determined in accordance with applicable law, (vi) governmental authority to limit, delay or prohibit the making of payments outside of the United States or in a foreign currency or currency unit and (vii) any laws except the DGCL or the laws of the State of New York. We advise you that issues addressed by this letter may be governed in whole or in part by other laws, but we express no opinion as to whether any relevant difference exists between the laws upon which our opinions are based and any other laws which may actually govern. We do not find it necessary for the purposes of this opinion, and accordingly we do not purport to cover herein, the application of the securities or “Blue Sky” laws of the various states to the issuance of the Securities.

This opinion is limited to the specific issues addressed herein, and no opinion may be inferred or implied beyond that expressly stated herein. We assume no obligation to revise or supplement this opinion should the DGCL be changed by legislative action, judicial decision or otherwise.

We hereby consent to the filing of this opinion with the Commission as Exhibit 5.1 to the Registration Statement. We also consent to the reference to our firm under the heading “Legal Matters” in the Registration Statement. In giving this consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Act or the rules and regulations of the Commission.