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                                                                 Note No. 3548-2
                                 PROMISSORY NOTE


$5,665,140.00                                                       July 6, 1999
                                                          Long Beach, California


         This Note is executed and delivered as of the date set forth above to
Boeing Capital Corporation, a Delaware corporation ("Lender"), by First Security
Bank, N.A., not in its individual capacity but solely as Owner Trustee under
Bell 412 Peru Trust No. 1, a Utah trust (the "Debtor"), in consideration of a
loan made pursuant to that certain Loan and Security Agreement ("Agreement")
dated June 11, 1999 between Lender and Debtor.

         Debtor promises to pay to Lender the principal sum of Five Million Six
Hundred Sixty-five Thousand One Hundred Forty dollars ($5,665,140.00) plus
interest on such principal sum from time to time outstanding at the rate of
9.8878% per annum. Interest shall be calculated on the basis of a 360-day year
for the actual number of days the principal is outstanding. Debtor's obligation
to Lender under this Note shall be payable in 120 consecutive monthly
installments each in the amount of $74,496.59 and each payable on the 6th day of
the month commencing August 6, 1999. Debtor agrees that Lender shall apply each
monthly installment payment first to any late payment fees and costs then due,
second to interest accrued and unpaid, and finally to the then outstanding
principal balance. Debtor's payments to Lender shall be credited on the day
Lender receives collected funds and no installment payment shall be considered
paid until Lender has received collected funds. All amounts paid hereunder shall
be paid by federal funds wire transfer or by Automated Clearing House (ACH)
payment format Cash Concentration and Disbursement Plus Addendum (CCD+) for the
account of Lender to a bank to be designated by Lender, together with notice so
as to provide Lender with use of the funds on or before 11 a.m., California
time, on the due date.

         In the event that Debtor fails to pay any installment payment(s) when
due, the principal balance, to the extent permitted by applicable law, shall
bear interest at a rate (the "Default Rate") of two percent (2%) per annum
greater than the interest rate stated in the second paragraph hereof, from the
due date until the date of payment in full of such installment payment(s).

         This Note is secured by the security interests Debtor has granted
Lender under the Agreement.

         Borrower may repay the loan at any time after the 36th month for an
amount equal to the sum of (i) the Prepayment Amount shown on Exhibit "A"
hereto, (ii) any break funding costs, and (iii) any other amounts due under the
Loan.


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         If an Event of Default occurs under the Agreement or under any other
Loan Document, then Lender shall have the right, without giving Debtor notice or
making a demand, to declare that the entire balance then due under this Note is
immediately payable (the "Accelerated Balance"). The Accelerated Balance shall
be calculated by adding to the principal balance outstanding: (i) interest
(including without limitation any interest at the Default Rate) on such
principal balance and (ii) any other amounts due hereunder.

         Debtor's default under this Note shall constitute a default under the
Agreement as well.

         Debtor's obligations under this Note are absolute and unconditional.
Debtor waives its right to assert any claim, counterclaim, right of offset or
affirmative defense it may have against Lender in any lawsuit Lender brings to
collect this Note, although Debtor may bring such claim in a separate lawsuit
against Lender.

         If Lender decides to waive strict compliance by Debtor of Debtor's
obligations under this Note, the waiver shall apply only to the specific right
or remedy at the time of such waiver, and Debtor shall not be excused from
strict compliance with Debtor's obligations at other or future times, nor may
Debtor rely on any waiver being applicable to prevent Lender from exercising
Lender's rights and remedies at other or future times or as a consequence of
other failures by Debtor to strictly comply with Debtor's obligations under this
Note or the other Loan Documents.

         Lender's rights and remedies under this Note or the other Loan
Documents are in addition to, and not exclusive of, any other rights or remedies
to which Lender may be entitled by operation of law or in equity. Lender may
collect this Note by proceeding against Debtor, any collateral given to secure
this Note or against any guarantor, endorser or other Person liable to Lender
for the obligations evidenced by this Note, and Lender may so proceed after
default, in any order, at any time or simultaneously as Lender decides in its
sole discretion.

         Debtor waives demand for payment, protest, notice of dishonor and other
notices or formalities to which Debtor might be entitled.

         Notwithstanding any provision to the contrary herein, or in any of the
documents evidencing the Obligations or otherwise relating thereto, no such
provision shall require the payment or permit the collection of interest in
excess of the maximum permitted by applicable usury laws. If any such excessive
interest is so provided for, then in such event: (i) the provisions of this
paragraph shall govern and control; (ii) neither the Debtor nor its heirs, legal
representatives, successors or assigns or any other party liable for the payment
thereof shall be obligated to pay the amount of such interest to the extent that
it is in excess of the maximum amount permitted by law; (iii) any such excess
interest that may have been collected shall be, at the option of the holder of
the instrument evidencing the Obligations, either applied as a credit against
the unpaid principal amount thereof or refunded to the


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maker thereof; and (iv) the effective rate of interest shall be automatically
reduced to the maximum lawful rate under applicable usury laws as now or
hereafter construed by the courts having jurisdiction.

         This Note is a negotiable instrument. Lender may sell, assign, transfer
or endorse this Note. If Lender does so, all of Debtor's obligations shall then
run to the Person to whom Lender sells, assigns, transfers or endorses this
Note, or to Lender's successors and assigns provided, however, that no such
assignment shall be binding on Debtor until notice of the same has been given
Debtor. If more than one Person has executed this Note, the obligations of each
Person so signing shall be joint and several. Capitalized terms not defined
herein shall have the meaning ascribed to them in the Agreement.

                                                BELL 412 PERU TRUST NO. 1
                                                By: FIRST SECURITY BANK,
                                                NATIONAL ASSOCIATION, not in its
                                                individual capacity, but solely
                                                as Owner Trustee

                                                By:  /s/ Greg A. Hawley
                                                   ---------------------------
                                                Name:   Greg A. Hawley
                                                   ---------------------------
                                                Title:  Vice President
                                                   ---------------------------


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