SECURITIES AND EXCHANGE COMMISSION
                                           WASHINGTON, DC 20549
                           ----------------------------------------------------

                                      AMENDMENT NO. 3 ON FORM 10-K/A

(mark one)
[ X ] Annual Report Pursuant to Section 13 or 15(d) of the Securities
      Exchange Act of 1934 for the fiscal year ended October 3, 1998

[   ] Transition Report Pursuant to Section 13 or 15(d) of the Securities
      Exchange Act of 1934

                         Commission file number 1-10573

                            THERMO POWER CORPORATION
             (Exact name of Registrant as specified in its charter)

Massachusetts                                                   04-2891371
(State or other jurisdiction of
 incorporation or organization)        (I.R.S. Employer Identification No.)

81 Wyman Street, P.O. Box 9046
Waltham, Massachusetts                                           02454-9046
(Address of principal executive offices)                         (Zip Code)

       Registrant's telephone number, including area code: (781) 622-1000

           Securities registered pursuant to Section 12(b) of theAct:

        Title of each class                Name of exchange on which registered
   Common Stock, $.10 par value                    American Stock Exchange

           Securities registered pursuant to Section 12(g) of the Act:
                                      None

Indicate by check mark whether the Registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months, and (2) has been subject to the filing requirements for
at least the past 90 days. Yes [ X ] No [ ]

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405
of Regulation S-K is not contained herein, and will not be contained, to the
best of the Registrant's knowledge, in definitive proxy or information
statements incorporated by reference into Part III of this Form 10-K or any
amendment to this Form 10-K. [ ]

The aggregate market value of the voting stock held by nonaffiliates of the
Registrant as of October 30, 1998, was approximately $18,451,000.

As of October 30, 1998, the Registrant had 11,830,163 shares of Common Stock
outstanding.

                       DOCUMENTS INCORPORATED BY REFERENCE

Portions of the Registrant's Annual Report to Shareholders for the fiscal year
ended October 3, 1998, are incorporated by reference into Parts I and II.



                                                                    FORM 10-K/A

                            THERMO POWER CORPORATION


Item 14. Exhibits, Financial Statement Schedules, and Reports on Form 8-K

(a, d)   Financial Statements and Schedules

         Financial Statement Schedules filed herewith:

            Schedule II: Valuation and Qualifying Accounts. See attached.

(c)   Exhibits

      13 Annual Report to Shareholders for the Fiscal Year Ended October 3, 1998
         (only these portions incorporated herein by reference).

      23 Consent of Arthur Andersen LLP.

      Attached is Exhibit 13 and Schedule II of the Registrant's Form 10-K for
the year ended October 3, 1998. The Registrant's financial statements have been
amended principally to modify disclosures concerning certain restructuring
actions and other subsequent events. This amended information replaces the
corresponding information filed originally in the Form 10-K.


                                       2



                                                                    FORM 10-K/A

                                   SIGNATURES


      Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the Registrant has duly caused this report to be signed by
the undersigned, thereunto duly authorized.

Date:  September 22, 1999          THERMO POWER CORPORATION


                                   By: /s/ J. Timothy Corcoran
                                       J. Timothy Corcoran
                                       President and Chief Executive Officer




                                       3



                    Report of Independent Public Accountants

To the Shareholders and Board of Directors of Thermo Power Corporation:

      We have audited, in accordance with generally accepted auditing standards,
the consolidated financial statements included in Thermo Power Corporation's
Annual Report to Shareholders incorporated by reference in this Amendment No. 3
on Form 10-K/A, and have issued our report thereon dated November 9, 1998
(except with respect to certain matters discussed in Notes 4 and 15, as to which
the date is July 3, 1999). Our audits were made for the purpose of forming an
opinion on those statements taken as a whole. The schedule listed in Item 14 on
page 2 is the responsibility of the Company's management and is presented for
purposes of complying with the Securities and Exchange Commission's rules and is
not part of the basic consolidated financial statements. This schedule has been
subjected to the auditing procedures applied in the audits of the basic
consolidated financial statements and, in our opinion, fairly states in all
material respects the consolidated financial data required to be set forth
therein in relation to the basic consolidated financial statements taken as a
whole.



                                                         Arthur Andersen LLP



Boston, Massachusetts
November 9, 1998


                                       4




SCHEDULE II                                                                               FORM 10-K/A

                                         THERMO POWER CORPORATION
                                    Valuation and Qualifying Accounts
                                              (In thousands)
                                                                              

                                      Balance
                                           at     Provision
                                    Beginning       Charged               Accounts                 Balance
                                           of            to    Accounts    Written                  at End
Description                              Year       Expense   Recovered        Off   Other (a)     of Year
- ----------------------------------- ---------- ------------- ----------- ---------- ----------- -----------

Allowance for Doubtful Accounts

Year Ended October 3, 1998             $  757      $    200   $     208     $ (491)    $ 9,625     $10,299

Year Ended September 27, 1997          $  589      $    252   $       3     $  (87)    $     -     $   757

Year Ended September 28, 1996          $  530      $    191   $      26     $ (158)    $     -     $   589


Description                        Balance at   Established    Activity                 Balance
                                    Beginning    as Cost of     Charged                  at End
                                      of Year  Acquisitions  to Reserve   Other (c)     of Year
- ----------------------------------- ---------- ------------- ----------- ---------- -----------

Accrued Acquisition Expenses (b)

Year Ended October 3, 1998           $     33    $    7,364    $ (5,311)   $     -     $ 2,086

Year Ended September 27, 1997        $    519    $        -    $     (7)   $  (479)    $    33

Year Ended September 28, 1996        $    680    $        -    $   (109)   $   (52)    $   519


Description                        Balance at     Provision    Activity                Balance
                                    Beginning    Charged to  Charged to                 at End
                                      of Year       Expense     Reserve      Other     of Year
- ----------------------------------- ---------- ------------- ----------- ---------- -----------

Reserve for Discontinued
    Operations (d)

Year Ended October 3, 1998             $    -      $    993   $       -       $  -     $   993

(a) Includes allowances of businesses acquired and discontinued during the year
    as described in Notes 3 and 4, respectively, to Consolidated Financial
    Statements in the Registrant's Fiscal 1998 Annual Report to Shareholders and
    the effect of foreign currency translation.
(b) The nature of activity in this account is described in Note 3 to
    Consolidated Financial Statements in the Registrant's Fiscal 1998 Annual
    Report to Shareholders.
(c) Represents reductions of cost in excess of net assets of acquired companies
    for accrued acquisition expenses no longer considered necessary.
(d) The nature of activity in this account is described in Note 4 to
    Consolidated Financial Statements in the Registrant's Fiscal 1998 Annual
    Report to Shareholders.