[LETTERHEAD OF WACHTELL, LIPTON, ROSEN & KATZ]

                                                                     EXHIBIT 5.1


                                          September 24, 1999


Alaska Communications Systems Holdings, Inc.
510 L. Street, Suite 500
Anchorage, Alaska 99501

Ladies and Gentlemen:

    We have acted as counsel for Alaska Communications Systems Holdings, Inc., a
Delaware corporation (the "Company"), in connection with the preparation of the
Company's Registration Statement on Form S-4, registration number 333-82363 (the
"Registration Statement"), first filed with the Securities and Exchange
Commission on July 7, 1999, relating to an offer to exchange (the "Exchange
Offer") 9 3/8% Senior Subordinated Notes due 2009 of the Company (the "Exchange
Notes") which will have been registered under the Securities Act of 1933, as
amended, for an equal principal amount of the Company's outstanding 9 3/8%
Senior Subordinated Notes due 2009 (the "Old Notes"). The Exchange Notes will be
guaranteed on a senior subordinated basis (the "Guarantees") by ALEC Holdings,
Inc., the sole stockholder of the Company, and each of the Company's domestic
subsidiaries (collectively, the "Guarantors").

    The Exchange Notes will be issued under an Indenture dated as of May 14,
1999 (the "Indenture"), among the Company, the Guarantors and IBJ Whitehall Bank
& Trust Company, as trustee (the "Trustee").

    As counsel, we have examined the Registration Statement, the Indenture, the
form of the Exchange Notes, the form of the Old Notes and such other documents,
records and other matters as we have deemed necessary or appropriate in order to
give the opinions set forth herein.

    In giving the opinions contained herein, we have, with your approval, relied
upon representations of officers of the Company and the Guarantors and
certificates of public officials with respect to the accuracy of the material
factual matters addressed by such representations and certificates. We have,
with your approval, assumed the genuineness of all signatures or instruments
submitted to us, and the conformity or certified copies submitted to us with the
original documents to which such certified copies relate.

    We are members of the bar of the State of New York and we express no opinion
as to the laws of any jurisdiction other than the federal laws of the United
States and the laws of the State of New York. In addition, we express no opinion
as to the effects of either (i) Section 548 of Title 11 of the United States
Code or (ii) Article 10 of the New York Debtor and Creditor Law, relating to
fraudulent transfers, on any obligation under the Guarantees of the Guarantors
that are direct or indirect subsidiaries of the Company.

    Based upon and subject to the foregoing, assuming that the Indenture has
been duly authorized, executed and delivered by, and represents the valid and
binding obligations of, the Trustee, it is our opinion that:

    (1) the Indenture has been duly executed and delivered by, and constitutes
       the legal, valid and binding obligation of, the Company and each of the
       Guarantors, as the case may be, enforceable against the Company and each
       of the Guarantors, as the case may be, in accordance with its terms;

    (2) the Exchange Notes, when duly executed and delivered by the Company upon
       the terms set forth in the Exchange Offer, will constitute legal, valid
       and binding obligations of the Company, enforceable against the Company
       in accordance with their respective terms; and


Alaska Communications Systems Holdings, Inc.
September 24, 1999
Page 2


    (3) the Guarantees will constitute the legal, valid and binding obligations
       of the Guarantors, enforceable against the Guarantors in accordance with
       their respective terms;


subject in each case to (a) bankruptcy, insolvency, moratorium, reorganization
and other laws of general applicability relating to or affecting creditors'
rights from time to time in effect and (b) application of general principles of
equity, including standards of commercial reasonableness and good faith
(regardless of whether considered in proceedings in equity or at law).


    We express no opinion with respect to: (i) the enforceability of provisions
in the Indenture relating to delay or omission of enforcement of rights or
remedies, or waivers of defenses, or waivers of benefits of usury, appraisement,
valuation, stay, extension, moratorium, redemption, statutes of limitation, or
other non-waivable benefits bestowed by operation of law; or (ii) the lawfulness
or enforceability of exculpation clauses, clauses relating to releases of
unmatured claims, clauses purporting to waive unmatured rights, severability
clauses, and clauses similar in substance or nature to those expressed in the
foregoing clause (i) and this clause (ii), insofar as any of the foregoing are
contained in the Indenture. In addition, we express no opinion as to whether a
federal or state court outside of the State of New York would give effect to the
choice of New York law provided for in the Indenture.

    We consent to the use of this opinion as an Exhibit to the Registration
Statement and to the reference to our firm in the Prospectus that is a part of
the Registration Statement. In giving such consent, we do not hereby admit that
we are in the category of persons whose consent is required under Section 7 of
the Securities Act of 1933.

                                          Very truly yours,
                                          Wachtell, Lipton, Rosen & Katz