================================================================================

                                 UNITED STATES
                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549

                                   FORM 13F

                              FORM 13F COVER PAGE

Report for the Calendar Year or Quarter Ended: December 31, 2009

Check here if Amendment [  ]; Amendment Number: ______________

This Amendment (Check only one.): [  ] is a restatement.
                                  [  ] adds new holdings entries.

Institutional Investment Manager Filing this Report:

Name: Caledonia Investments plc

Address: Cayzer House, 30 Buckingham Gate, London England SW1E 6NN

Form 13F File Number: 028-13011

The institutional investment manager filing this report and the person by whom
it is signed hereby represent that the person signing the report is authorized
to submit it, that all information contained herein is true, correct and
complete, and that it is understood that all required items, statements,
schedules, lists, and tables, are considered integral parts of this form.

Person Signing this Report on Behalf of Reporting Manager:

Name: Mr. Graeme P. Denison
Title: Company Secretary
Phone: 44-20-7802-8080

Signature, Place, and Date of Signing:

  /s/ GRAEME P. DENISON        London, England           January 14, 2010
 ------------------------  ------------------------  ------------------------
       [Signature]               City, State                  [Date]

Report Type (Check only one.):

[X]13F HOLDINGS REPORT. (Check here if all holdings of this reporting manager
   are reported in this report.)

[_]13F NOTICE. (Check here if no holdings reported are in this report, and all
   holdings are reported by other reporting manager(s).)

[_]13F COMBINATION REPORT. (Check here if a portion of the holdings for this
   reporting manager are reported in this report and a portion are reported by
   other reporting manager(s).)

================================================================================



                             FORM 13F SUMMARY PAGE


                                      
Report Summary:

Number of Other Included Managers:            0
                                         ----------
Form 13F Information Table Entry Total:       1
                                         ----------
Form 13F Information Table Value Total:    $90,434
                                         ----------
                                         (thousands)
List of Other Included Managers:

NONE






                           Caledonia Investments plc
                          FORM 13F INFORMATION TABLE
                               December 31, 2009



                                                    SHRS                                      VOTING AUTHORITY
                     TITLE OF             VALUE    OR PRN          PUT/ INVESTMENT  OTHER   ---------------------
NAME OF ISSUER        CLASS     CUSIP   (X$1,000)   AMT     SH/PRN CALL DISCRETION MANAGERS   SOLE    SHARED NONE
- --------------       -------- --------- --------- --------- ------ ---- ---------- -------- --------- ------ ----
                                                                            
Bristow Group, Inc.   Common  110394103  $90,434  2,352,000   SH           SOLE             2,352,000