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                                  EXHIBIT 10.2

                                 PROMISSORY NOTE


$1,500,000.00                                             Minneapolis, Minnesota
                                                              September 21, 2001


1. FOR VALUE RECEIVED, Aero Systems Engineering, Inc., a Minnesota corporation
(the "Borrower"), hereby promises to pay to the order of Celsius, Inc., a
Delaware corporation (the "Holder"), at such location as the Holder may direct,
the principal sum of One Million Five Hundred Thousand and 00/100 Dollars
($1,500,000.00), in lawful money of the United States and immediately available
funds, together with interest on the unpaid balance accruing as of and from the
date hereof at a rate equal to two percent (2%) per quarter.

2. Interest payments shall be made quarterly on March 31, June 30, September 30,
and December 31 of each year, with the entire outstanding principal balance of
this Note, together with any and all accrued and unpaid interest hereon, due and
payable in full on September 21, 2004.

3. The outstanding principal balance of this Note may be prepaid at any time at
the option of the Borrower, in whole or in part without premium or penalty.

4. All payments and prepayments shall, at the option of the Holder, be applied
first to any costs of collection, second to accrued interest on this Note, and
lastly to principal.

5. Notwithstanding anything to the contrary contained herein, if the rate of
interest or any other amounts due hereunder are determined by a court of
competent jurisdiction to be usurious, then said interest rate and/or amounts
shall be reduced to the maximum amount permissible under applicable Minnesota
law.

6. This Note is secured by a certain Combination Mortgage, Assignment Of Rents,
Security Agreement And Fixture Financing Statement of even date herewith
executed by the Borrower in favor of the Holder (the "Security Agreement"),
which Security Agreement is junior and subordinate to that certain security
interest of National City Bank of Minneapolis (and any successors or
replacements thereof), granted September 21, 2001 pursuant to an agreement
between the Holder and such Bank.

7. Upon the occurrence of an Event of Default (as defined herein) or at any time
thereafter, the outstanding principal balance hereof and accrued interest and
all other amounts due hereon shall, at the option of the Holder, become
immediately due and payable, without notice or demand. During the occurrence of
an Event of Default interest shall accrue at the rate of fourteen percent (14%)
per annum.





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8. Upon the occurrence of an Event of Default (as defined herein) or anytime
thereafter, the Holder shall have the right to set off any and all amounts due
hereunder by the Borrower to the Holder against any indebtedness or obligation
of the Holder to the Borrower.

9. Upon the occurrence at any time of an Event of Default (as defined herein) or
at any time thereafter, the Borrower promises to pay all costs of collection of
this Note, including but not limited to reasonable attorneys' fees, paid or
incurred by the Holder on account of such collection, whether or not suit is
filed with respect thereto and whether such cost or expense is paid or incurred,
or to be paid or incurred, prior to or after the entry of judgment.

10. As used herein, the term "Event of Default" shall mean the occurrence of any
one or more of the following:

         a.       The Borrower shall fail to pay, when due, any amounts required
                  to be paid by the Borrower under this Note; or

         b.       The Borrower shall be in default under the Security Agreement,
                  the Pledge Agreement dated the date hereof in favor of the
                  Holder, or under any material agreement with any lender to the
                  Company, where such default has not been cured or waived
                  within any applicable grace period; or

         c.       The Borrower shall file or have filed against it a petition in
                  bankruptcy or for an arrangement pursuant to any present or
                  future state or federal bankruptcy act or under a similar
                  federal or state law, or shall be adjudicated a bankrupt or
                  insolvent, or shall make a general assignment for the benefit
                  of creditors, or shall be unable to pay its debts generally as
                  they become due, or any property of the Borrower shall be
                  levied upon or attached in any proceeding.

11. Demand, presentment, protest and notice of nonpayment and dishonor of this
Note are hereby waived.

12. This Note shall be governed by and construed in accordance with the laws of
the state of Minnesota.

13. This Note is subject to the provisions of that certain Debt Subordination
Agreement executed by the Holder in favor of National City Bank of Minneapolis,
Minnesota dated September 21, 2001.

                                       AERO SYSTEMS ENGINEERING, INC.,
                                       a Minnesota corporation


                                       By: /s/ CHARLES LOUX
                                           -------------------------------------
                                               Charles Loux
                                               Its: President and Chief
                                                 Executive Officer





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