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                                                                     EXHIBIT 5.1



                                    February
                                      24th
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                                                                       613,257-8


First Aviation Services Inc.
One Omega Drive
Stamford, Connecticut 06907

                 Re:      First Aviation Services Inc. Registration
                          Statement on Form S-1 (Registration No. 333-18647)

Ladies and Gentlemen:

                 At your request, we have examined the Registration Statement
on Form S-1 (Registration No. 333-18647) filed by you with the Securities and
Exchange Commission (in connection with the registration under the Securities
Act of 1933, as amended, of 3,900,000 shares of Common Stock, $0.01 par value
(the "Shares"), of First Aviation Services, a Delaware corporation (the
"Corporation").  We are familiar with the proceedings taken and proposed to be
taken by you in connection with the authorization and proposed issuance and
sale of the Shares.

                 It is our opinion that, subject to said proceedings being duly
taken and completed by you as now contemplated prior to the issuance of the
Shares, the Shares will, upon issuance and sale thereof in the manner referred
to in the Registration Statement, be validly issued, fully paid and
nonassessable shares of Common Stock of the Corporation.

                 The law covered by this opinion is limited to the present
General Corporation Law of the State of Delaware.  We express no opinion as to
the laws of any other jurisdiction and no opinion regarding the statutes,
administrative decisions, rules, regulations or requirements of any county,
municipality, subdivision or local authority of any jurisdiction.
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Page 2 - First Aviation Services Inc. - February 24, 1997



                 We consent to your filing this opinion as an exhibit to the
Registration Statement and to the reference to us in the Registration Statement
under the heading "Legal Matters."

                                        Respectfully submitted,



                                        /s/ O'MELVENY & MYERS LLP
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