1 EXHIBIT 15 LETTER RE: UNAUDITED FINANCIAL INFORMATION Board of Directors and Shareholders TRW Inc. We are aware of the incorporation by reference in the following registration statements and in the related prospectuses of our report dated April 19, 2000 relating to the unaudited consolidated interim financial statements of TRW Inc. that is included in its Form 10-Q for the quarter ended March 31, 2000: Form S-4 333-83227 Form S-3 333-89133 Form S-3 333-48443 Form S-8 333-36052 Form S-8 333-27003 Form S-8 333-27001 Form S-8 333-20351 Form S-8 333-06633 Form S-8 333-03973 Form S-8 33-53503 Form S-8 33-29751 Form S-8 2-90748 Form S-8 2-64035 /s/ Ernst & Young LLP May 4, 2000 Cleveland, Ohio