Exhibit 11.1 Computation of Earnings EXHIBIT XI WILLIS LEASE FINANCE CORPORATION Computation of Earnings Per Share Three Months Ended March 31 ----------------------------- Income before extraordinary item 1999 1998 --------------- ------------ (in thousands, except per share data) Basic Earnings: Income before extraordinary item $2,785 $1,949 Shares: Weighted average number of common shares outstanding 7,363 7,192 --------------- ------------ Basic earnings per common share before extraordinary item $0.38 $0.27 Assuming Full Dilution Earnings: Income before extraordinary item $2,785 $1,949 --------------- ------------ Shares: Weighted average number of common shares outstanding and common stock equivalents 7,450 7,440 --------------- ------------ Earnings per common share assuming full dilution, $0.37 $0.26 before extraordinary item --------------- ------------ Net income Basic Earnings: Net income $2,785 $1,749 --------------- ------------ Shares: Weighted average number of common shares outstanding 7,363 7,192 --------------- ------------ Basic earnings per common share $0.38 $0.24 Assuming Full Dilution Earnings: Net income $2,785 $1,749 --------------- ------------ Shares: Weighted average number of common shares outstanding and common stock equivalents 7,450 7,440 --------------- ------------ Earnings per common share assuming full dilution $0.37 $0.23 =============== ============ Supplemental information: Difference between weighted average number of common shares outstanding to calculate basic and assuming full dilution is due to options outstanding under the 1996 Stock Options/Stock Issuance Plan 21