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                                                                  EXHIBIT 11.1



                       IRIDIUM WORLD COMMUNICATIONS LTD.

                 COMPUTATION OF LOSS PER CLASS A COMMON SHARES
                        (In Thousands Except Share Data)

<TABLE>
<CAPTION>
                                                                       THREE MONTHS ENDED MARCH 31,
                                                             --------------------------------------------
                                                                     1997                     1998             
                                                             -------------------      -------------------
<S>                                                            <C>                      <C>  
NET LOSS APPLICABLE TO CLASS A COMMON SHARES:                                         
                                                                                      
Net loss                                                       $              -         $         17,426 
                                                             -------------------      -------------------
Net loss applicable to Class A Common shares                   $              -         $         17,426 
                                                             ===================      ===================
                                                                                      
AVERAGE NUMBER OF CLASS A SHARES:                                                     
                                                                                      
Average number of Class A Common shares outstanding                           -               12,008,654
                                                                                      
Diluted adjustments (2):                                                              
     Assumed exercise of options and warrants                                 -                1,560,000 
                                                             -------------------      -------------------
                                                                                      
Average number of Class A Common shares assumed to be                                 
     outstanding, assuming dilution                                           -               13,568,654 
                                                             ===================      ===================
                                                                                      
NET LOSS PER CLASS A COMMON SHARE:                                                    
                                                                                      
Basic (1)                                                      $              -         $           1.45
                                                                                      
Diluted (2)                                                    $              -         $           1.28
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(1)    The assumed exercise of options and warrants in periods of net loss are
       anti-dilutive and are not included in the computation and presentation
       of loss per Class A Common share.

(2)    The assumed exercise of options and warrants are anti-dilutive but are
       included in the calculation of diluted loss per Class A Common share in
       accordance with Regulation S-K, Item 601 (a) (11).


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