EXHIBIT 10.8.3

                    ACKNOWLEDGMENT AND AGREEMENT (MSN 22237)

            ATLAS AIR WORLDWIDE HOLDINGS,  INC., a Delaware  corporation ("ATLAS
HOLDINGS"),  with reference to (i) the Amendment Agreement (MSN 22237), dated as
of August 1, 2003 (the  "AGREEMENT"),  between Polar Air Cargo, Inc.  ("LESSEE")
and Polaris Aircraft (Pacific Rim), Inc. ("LESSOR"),  and (ii) the Restructuring
Letter  Agreement  (MSN  22237),  dated  as  of  August  1,  2003  (the  "LETTER
AGREEMENT"),  between Lessee and Lessor,  DOES HEREBY ACKNOWLEDGE AND AGREE (to,
with and for the benefit of Lessor and its  successors  and assigns)  that Atlas
Holdings is bound by, and obligated to perform and observe, and hereby agrees to
perform and observe, the terms,  provisions,  conditions and covenants contained
in Sections 2(d),  2(f), 4(c), 7 and 8 of the Agreement and Part I of the Letter
Agreement  (and  expressed  as being  applicable  to or in  respect of a "Lessee
Party" a "Lessee Party" other than Lessee, "Atlas Holdings" or an "Affiliate" of
Lessee),  in each case, with the same force and effect as if Atlas Holdings were
a party to the Agreement and the Letter  Agreement (in the capacity of a "Lessee
Party" or "Atlas Holdings").

                            [Signature Page Follows]


            IN WITNESS  WHEREOF,  Atlas Holdings has caused this  Acknowledgment
and  Agreement  to be executed  and  delivered  as of this 18th day of November,
2003.

                                              ATLAS AIR WORLDWIDE HOLDINGS, INC.


                                              By /s/ Jeffrey H. Erickson
                                                 -------------------------------
                                                 Name: Jeffrey H. Erickson
                                                 Title: President & COO

      [Signature Page to Acknowledgment, Consent and Agreement (MSN 22237)]