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                                                                    EXHIBIT 10.6





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                    STANDBY SERVICING, ADMINISTRATIVE AGENCY
                          AND CASH MANAGEMENT AGREEMENT


                                      among


                         debis Aircraft Leasing Limited


                             debis AirFinance B.V.,
                                  as Guarantor


                                       and


                                  AerCo Limited




                            Dated as of July 17, 2000



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         STANDBY SERVICING, ADMINISTRATIVE AGENCY AND CASH MANAGEMENT AGREEMENT
dated as of July 17, 2000 (this "AGREEMENT"), among debis Aircraft Leasing
Limited, a limited company organized under the laws of Ireland (the "STANDBY
SERVICER"), debis AirFinance B.V., a limited company organized under the laws of
The Netherlands (the "GUARANTOR"), and AerCo Limited, a company incorporated
under the laws of Jersey (the "COMPANY").

         WHEREAS, the Company has entered into a Servicing Agreement (the "AerFi
SERVICING AGREEMENT") dated as of July 17, 2000 with, among others, AerFi Group
plc (the "SERVICER").

         WHEREAS, the Company has entered into an Amended and Restated
Administrative Agency Agreement dated as of July 17, 2000, with, among others,
AerFi Administrative Services Limited (the "AerFi ADMINISTRATIVE AGENCY
AGREEMENT").

         WHEREAS, the Company has entered into an Amended and Restated Cash
Management Agreement, dated as of July 17, 2000, with, among others, AerFi Cash
Manager II Limited (the "AerFi CASH MANAGEMENT AGREEMENT").

         WHEREAS, the Company and the Standby Servicer have agreed that the
Standby Servicer will provide the services defined herein on the terms and
conditions set out herein and following the Start Date (as defined below), if
any, subject to the terms and conditions of each of (i) the Servicing Agreement
among the Company, the Standby Servicer, the Guarantor and others dated as of
July 17, 2000 (the "SERVICING AGREEMENT") attached hereto as Annex 1, (ii) the
Administrative Agency Agreement among the Company, the Standby Servicer, the
Guarantor and others dated as of July 17, 2000 (the "ADMINISTRATIVE AGENCY
AGREEMENT") attached hereto as Annex 2 and (iii) the Cash Management Agreement
among the Company, the Standby Servicer, the Guarantor and others dated as of
July 17, 2000 (the "CASH MANAGEMENT AGREEMENT") attached hereto as Annex 3.

         NOW, THEREFORE, for the consideration set forth herein and other good
and valuable consideration, the receipt of which is hereby acknowledged, the
parties hereto agree as follows:


                                    ARTICLE 1
                                   DEFINITIONS

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         SECTION 1.01. Definitions. Defined terms in the Servicing Agreement,
the Administrative Agency Agreement and the Cash Management Agreement shall have
the same meanings herein. In addition, the following defined terms shall have
effect:

         "AGREEMENT" has the meaning assigned to such term in the preamble
hereto.

         "COMPANY" has the meaning assigned to such term in the preamble hereto.

         "GUARANTOR" has the meaning assigned to such term in the preamble
hereto.

         "RELATED DOCUMENTS" has the meaning assigned to such term in the
Indenture dated as of July 15, 1998, between the Company and Bankers Trust
Company, a New York banking corporation, not in its individual capacity, but
solely as trustee, as amended or supplemented from time to time.

         "RELEVANT SERVICES" means the Services, the Administrative Services and
the Cash Management Services (as defined, respectively, in the Servicing
Agreement, Administrative Agency Agreement and Cash Management Agreement) which
the Company may require the Standby Servicer to perform hereunder.

         "STANDBY PERIOD" has the meaning specified in Section 4.01 hereof.

         "STANDBY SERVICER" has the meaning assigned to such term in the
preamble hereto.

         "STANDBY TERMINATION FEE" has the meaning specified in Section 5.01
hereof.

         "START DATE" means, the date specified by the Company in the Start
Notice as the date upon which the Standby Servicer is to commence performance of
the Relevant Services, which shall be the date on which the AerFi Servicing
Agreement, the AerFi Administrative Agency Agreement and the AerFi Cash
Management Agreement are anticipated to terminate.

         "START NOTICE" means a notice in writing from the Company to the
Standby Servicer specifying the Start Date in respect of the Relevant Services.


                                    ARTICLE 2


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                                   APPOINTMENT

         SECTION 2.01. Appointment. The Company hereby appoints the Standby
Servicer as its agent on the terms and conditions set forth in this Agreement to
provide the Relevant Services to the Company and its Subsidiaries with effect
from the Start Date.

         SECTION 2.02. Acceptance of Appointment. The Standby Servicer hereby
accepts such appointment and agrees to perform with effect from the Start Date
the Relevant Services on the terms and subject to the conditions set forth in
this Agreement; provided, however, that it shall not be a condition to the
Standby Servicer's performance of services that it shall have received a Start
Notice.


                                    ARTICLE 3
                                RELEVANT SERVICES

         SECTION 3.01. Relevant Services. The obligations to be performed by the
Standby Servicer are (i) those obligations of the "Servicer" set forth in the
Servicing Agreement, (ii) those obligations of the "Administrative Agent" set
forth in the Administrative Agency Agreement and (iii) those obligations of the
"Cash Manager" set forth in the Cash Management Agreement.

         SECTION 3.02.  Condition.  The obligations of the Standby Servicer set
forth in Section 3.01 above are subject to the issuance by the Company of a
Start Notice.

         SECTION 3.03. Additional Information. (a) The Company shall deliver, or
cause the Servicer to deliver, to the Standby Servicer as soon as available and
in any event within 90 days after each anniversary date of this Agreement prior
to the Start Date, such documentation and reports as shall be agreed between the
Company and the Standby Servicer; (including without limitation all filings by
AerCo under the Securities Exchange Act of 1934) provided, however, that the
Company shall not be required to provide the Standby Servicer with any
information regarding the Leases (other than the identity of the Lessees and
their current performance), sales of aircraft or any marketing of the aircraft
or Leases. The Standby Servicer agrees to review all information provided to
it pursuant to the preceding sentence.

          (b) The Company shall also furnish to the Standby Servicer a copy of
any termination notice delivered or received by the Company under the AerFi


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Servicing Agreement, the AerFi Administrative Agency Agreement or the AerFi Cash
Management Agreement.



                                    ARTICLE 4
                                  REMUNERATION

         SECTION 4.01.  Remuneration.  (a) From the date of this Agreement until
the Start Date (the "STANDBY PERIOD"), the Standby Servicer shall be entitled to
a fee of $80,000 (Eighty Thousand US dollars) per annum payable monthly in
arrears.

         (b) From the Start Date, the Standby Servicer shall in its capacity as
servicer, administrative agent and cash manager be entitled to receive such fees
as are payable under, respectively, Article 9 of the Servicing Agreement,
Article 8 of the Administrative Agency Agreement and Article 7 of the Cash
Management Agreement in relation to the Relevant Services performed by the
Standby Servicer.


                                    ARTICLE 5
                           TERMINATION AND RESIGNATION

         SECTION 5.01. Termination. (a) The Standby Servicer shall cease to be
the Standby Servicer hereunder if at any time during the Standby Period, the
Company shall have given 30 days' notice in writing to the Standby Servicer of
the Company's intention to terminate this Agreement; provided, however, that
this Agreement shall not terminate and the Standby Servicer shall not cease to
be the Standby Servicer hereunder unless a replacement standby servicer,
acceptable to the Company and the Rating Agencies shall have been appointed by
the Company. On the date specified in a notice pursuant to the foregoing
sentence, the appointment of the Standby Servicer hereunder shall cease in
accordance with such instructions or notice.

          (b) After the Standby Period, this Agreement shall terminate and the
obligations of the Standby Servicer under each of the Servicing Agreement, the
Administrative Agency Agreement and the Cash Management Agreement shall
terminate upon the date of termination in accordance with the terms of any of
the

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Servicing Agreement, the Administrative Agency Agreement and the Cash
Management Agreement.

         SECTION 5.02. Compensation. Any termination under Section 5.01(a)
hereof shall entitle the Standby Servicer to a termination fee of $80,000
(Eighty Thousand US dollars) (the "STANDBY TERMINATION FEE"). The Company may
terminate this Agreement at any time during the Standby Period without the 30
days' notice to the Standby Servicer required under Section 5.01(a) by paying
the Standby Servicer the Standby Termination Fee plus $7,000 (Seven Thousand US
dollars).

         Any such termination shall be without prejudice to the right of the
Standby Servicer to receive any accrued fee or reimbursement of any expense in
accordance with this Agreement and without prejudice to any accrued rights of
the parties hereto. Compensation pursuant to this Section 5.02 shall be payable
on the date of termination.

         SECTION 5.03. Information. Following termination the Standby Servicer
will promptly forward to the Company any notices, reports and communications
received by it from any Lessee under any Lease during the 60 days immediately
after termination.

         SECTION 5.04. Notification of Lessees on Termination. After the Start
Date, if any, the Company will notify promptly the Lessee under each Lease and
any relevant third party in the event of the termination of the Standby Servicer
under this Agreement and request that all notices, reports and communications
thereafter be made or given directly to the Company.

         SECTION 5.05. Co-operation. If the appointment of the Standby Servicer
is terminated hereunder, the Standby Servicer undertakes to co-operate with any
person appointed by the Company in place of the Standby Servicer, including
providing such person with all information and documents reasonably requested
provided that it is indemnified by the Company for any costs and expenses
reasonably incurred in so doing.

         SECTION 5.06. Obligations. Following termination of its appointment
hereunder the Standby Servicer shall have no further obligations hereunder other
than obligations accrued up to the date of termination; provided that the
Standby Servicer shall not be absolved or released from any liability for any
act or failure to act pursuant to this Agreement prior to the date of
termination.


                                    ARTICLE 6

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                                    GUARANTEE

         SECTION 6.01. Guarantee. The Guarantor hereby fully and unconditionally
guarantees to the Company (i) the due and punctual performance by the Standby
Servicer of all agreements, covenants and other obligations required to be
performed by the Standby Servicer hereunder or under any other Related Document
(including, without limitation, the punctual payment when due of all amounts now
or hereafter payable by the Standby Servicer hereunder or under any other
Related Document) (all such agreements, covenants and other obligations being
the "GUARANTEED OBLIGATIONS"), all in accordance with the terms of this
Agreement and the other Related Documents, and agrees to pay any and all
expenses (including counsel fees and expenses) incurred by any of the parties
hereto or any of their respective officers, directors or agents in enforcing any
right under this Section 6.01 (except costs of AerCo in an enforcement action in
which the remedies sought by AerCo are denied by a final court order). The
liability of the Guarantor under this Section 6.01 is limited to the maximum
amount that will result in the obligations of the Guarantor not constituting a
fraudulent conveyance or fraudulent transfer under applicable law.

         The Guarantor hereby waives diligence, presentment, filing of claims
with a court in the event of merger or bankruptcy of the Standby Servicer, any
right to require a proceeding first against the Standby Servicer, and the
benefit of discussion, protest or notice with respect to any and all demands for
performance or payment hereunder whatsoever (except as specified above), and
covenants that this Article 6 shall not be discharged except by performance or
payment in full of all of the Guaranteed Obligations.

         The Guarantor hereby irrevocably waives any claim or other rights which
it may now or hereafter acquire against the Standby Servicer that arise from the
existence, payment, performance or enforcement of the Guarantor's obligations
under this Agreement or any other Related Document, including, without
limitation, any right of subrogation, reimbursement, exoneration, contribution,
indemnification, any right to participate in any claim or remedy of any party
against the Standby Servicer, whether or not such claim, remedy or right arises
in equity, or under contract, statute or common law, including, without
limitation, the right to take or receive from the Standby Servicer, directly or
indirectly, in cash or other property or in any other manner, payment or
security on account of such claim or other rights, until all of the Guarantor's
obligations under this Agreement have been satisfied. If any amount shall be
paid to the Guarantor in violation of the preceding sentence and this Agreement
shall not have been terminated, such amount shall be deemed to have been paid to
the

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Guarantor for the benefit of, and held in trust for the benefit of the Company,
and shall forthwith be paid to the Company. The Guarantor acknowledges that it
will receive direct and indirect benefits from the execution, delivery and
performance by the Standby Servicer of this Agreement and that the waiver set
forth in this paragraph is knowingly made in contemplation of such benefits.

         SECTION 6.02. Reinstatement. The Guarantor hereby agrees that the
guarantee provided for in Section 6.01 hereof shall continue to be effective or
be reinstated, as the case may be, if at any time, payment, or any part thereof,
of any Guaranteed Obligations or interest thereon is rescinded or must otherwise
be restored to the Standby Servicer upon the bankruptcy or insolvency of the
Standby Servicer or the Guarantor or otherwise.

         SECTION 6.03. Unconditional Nature of Guarantee. The Guarantor hereby
agrees that its obligations under the guarantee set forth in Section 6.01 hereof
shall be irrevocable and unconditional, irrespective of the invalidity,
irregularity or unenforceability of this Agreement or any other Related Document
against the Standby Servicer, the absence of any action to enforce the Standby
Servicer's obligations hereunder or under any other Related Document, any waiver
or consent by any party hereto with respect to any provisions thereof, any
amendment to the terms hereof or of any other Related Document, the bankruptcy
of the Standby Servicer or any circumstance which might otherwise constitute a
legal or equitable discharge or defense of a guarantor; provided, however, that
the Guarantor shall be entitled to exercise any right that the Standby Servicer
could have exercised under this Agreement to cure any default in respect of its
obligations hereunder or under any other Related Document, if any, but only to
the extent such right, if any, is provided to the Standby Servicer hereunder or
under any other Related Document.



                                    ARTICLE 7
                                  MISCELLANEOUS

         SECTION 7.01. Term. Unless sooner terminated pursuant to Section 5.01
hereof, this Agreement shall terminate on the date of payment in full of all
amounts outstanding to be paid on the Notes (including the Class D Notes and the
Class E Notes) and any other securities issued by the Company as relating to
Additional Aircraft owned by AerCo Group.

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         SECTION 7.02. Notices. All notices, consents, directions, approvals,
instructions, requests and other communications shall be in writing, and any
such notices shall become effective upon (i) the earlier of receipt thereof and
five Business Days after being deposited in the mail, certified or registered,
return receipt requested, with appropriate postage prepaid for first class mail
and (ii) receipt if delivered by hand or courier service or by facsimile (and,
in the case of a facsimile, receipt of such facsimile is confirmed to the
sender) and shall be directed to the addresses or facsimile numbers of such
Person set forth below:

         If to the Standby Servicer, to:

         debis Aircraft Leasing Limited
         c/o debis AirFinance B.V.
         Evert van de Beekstraat 312
         NL-1118 CX Schipol Airport
         The Netherlands
         Attention:        Managing Director
         Copy:             General Counsel
         Facsimile:        31-20-6559-100

         If to the Guarantor, to:

         debis AirFinance B.V.
         Evert van de Beekstraat 312
         NL-1118 CX Schipol Airport
         The Netherlands
         Attention:        Managing Director
         Copy:             General Counsel
         Facsimile:        31-20-6559-100

         If to the Company, to:

         AerCo Limited
         22 Grenville Street
         St. Helier
         Jersey, JE4 8PX
         Channel Islands
         Attention:        Mourant & Co. Secretaries
                           Limited - Company Secretary
         Facsimile:        44-1534-609-333

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         With a copy to:

         AerFi Administrative Services Limited
         as Administrative Agent
         Aviation House
         Shannon
         Co. Clare, Ireland
         Attention:        Company Secretary
         Copy:             General Counsel
         Facsimile:        353-61-360-503

         From time to time either party to this Agreement may designate a new
address or number for purposes of notices hereunder by giving 15 days' notice in
writing.

         SECTION 7.03. Governing Law. This Agreement shall in all respects be
governed by and construed in accordance with the laws (excluding principles of
conflicts of laws) of the State of New York applicable to agreements made and to
be performed entirely within such state, including all matters of construction
validity and performance.

         SECTION 7.04. Jurisdiction; Court Proceedings. The parties hereto agree
that any suit, action or proceeding seeking to enforce any provision of, or
based on any matter arising out of or in connection with, this Agreement or the
transactions contemplated hereby may be brought in the United States District
Court for the Southern District of New York or any other New York State court
sitting in New York City, and each of the parties hereby consents to the
jurisdiction of such courts (and of the appropriate appellate courts therefrom)
in any such suit, action or proceeding and irrevocably waives, to the fullest
extent permitted by law, any objection which it may now or hereafter have to the
laying of the venue of any such suit, action or proceeding in any such court or
that any such suit, action or proceeding which is brought in any such court has
been brought in an inconvenient forum. Process in any such suit, action or
proceeding may be served on any party anywhere in the world, whether within or
without the jurisdiction of any such court. Without limiting the foregoing, each
party agrees that service of process on such party as provided in Section 7.02
or 7.06 hereof shall be deemed effective service of process on such party.

         SECTION 7.05.  Waiver of Jury Trial.  EACH OF THE PARTIES
HERETO HEREBY IRREVOCABLY WAIVES ANY AND ALL RIGHT TO
TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF OR
RELATED TO THIS AGREEMENT OR THE TRANSACTIONS
CONTEMPLATED HEREBY.

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         SECTION 7.06.  Agent.   Each of the Company, the Standby Servicer and
the Guarantor hereby appoints Corporation Service Company, 80 State Street, 6th
Floor, Albany, N.Y., 12207, U.S.A. as their respective nonexclusive agents for
service of process in the United States in connection with this Agreement.  The
parties may use any legally available means of service of process. Each party
hereto will promptly notify the other of any change in the address of their
respective agents, provided that the parties hereto will at all times maintain
agents located within New York State for service of process in connection with
this Agreement, the identity of any successor agent to be reasonably
satisfactory to the other party hereto.

         SECTION 7.07. Counterparts. This Agreement may be executed in separate
counterparts, each of which when so executed and delivered shall be an original,
but all such counterparts shall together constitute one and the same agreement.
All signatures need not be on the same counterpart.

         SECTION 7.08. Severability. In case any provision of or obligation
under this Agreement shall be invalid, illegal or unenforceable in any
jurisdiction, the validity, legality and enforceability of the remaining
provisions or obligations, or of such provision or obligation in any other
jurisdiction, shall not in any way be affected or impaired thereby.

         SECTION 7.09. Headings. Headings and captions used in this Agreement
are included for convenience of reference only and shall not constitute a part
of this Agreement for any other purpose or be given any substantive effect.


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         IN WITNESS WHEREOF, this Agreement has been duly executed on the date
first written above.

                                            DEBIS AIRCRAFT LEASING LIMITED,
                                            as Standby Servicer


                                            By: ____________________________
                                                Name:
                                                Title:


                                            DEBIS AIRFINANCE B.V.,
                                            as Guarantor


                                            By: ____________________________
                                                Name:
                                                Title:


                                            AERCO LIMITED


                                            By: ____________________________
                                                Name:
                                                Title:


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