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                                                                   Exhibit 10(b)

April 21, 1997

Martin A. Coyle
1900 Richmond Road
Cleveland, Ohio  44124

Dear Marty,

The following will confirm the changes we have agreed to in the severance
agreement dated February 25, 1997, which you signed on March 3, 1997
(hereinafter referred to as "the Agreement"):

1.       The first sentence of the paragraph entitled "Benefits," on page 4 of
         the Agreement is amended as follows:

         "Until the date of termination of your employment, all benefits and
         perquisites you currently have shall continue, except that at such time
         as you discontinue providing services to TRW or one of its
         subsidiaries, you will participate in non-qualified SRIP and BEP.
         Continuing as Chairman of TRW Investment Management Company and
         assuming the responsibilities thereunder shall be deemed `providing
         services'."

2.       In the Pension section, the first sentence in the last partial
         paragraph on page 8 of the Agreement is amended as follows:

         "In no event will your benefit service under the qualified SSP or under
         the nonqualified plans extend beyond your retirement date."

3.       Notwithstanding anything else in the Agreement, if you choose to retire
         earlier than March 1, 1999 or if you accept full-time employment (not
         meant to include voluntary or consulting efforts) outside of TRW prior
         to March 1, 1999, the following provisions will apply:

         a.       If you accept employment elsewhere, you must retire on the
                  first day of the month following your first day of employment
                  elsewhere (the "Early Retirement Date").

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Martin A. Coyle
April 21, 1997
Page 2

         b.       If you choose to retire earlier than March 1, 1999 (without
                  employment elsewhere), you must retire on the first day of the
                  month following your written notice to TRW indicating your
                  desire to retire (this date shall also be deemed the "Early
                  Retirement Date"). Your Early Retirement Date shall be deemed
                  your "termination of employment" under the Agreement.

         c.       If your Early Retirement Date occurs before March 1, 1999, you
                  will immediately receive in a lump sum (with appropriate
                  withholding) the base salary, OIP bonuses (at target) and SIP
                  payment you would otherwise had received if you had remained
                  employed until March 1, 1999, with the salary and bonuses you
                  would have received between (i) the later of June 1, 1998, and
                  your Early Retirement Date and (ii) March 1, 1999, offset by
                  the base salary and bonus, if any, you would expect to receive
                  from your new employer during such period. For purposes hereof
                  the SIP payment is equal to a cash payment of 20,000 shares
                  (as adjusted) times the average of the high and low price of
                  TRW stock on the last trading day prior to your Early
                  Retirement Date.

         d.       In addition, if you retire on or before February 1, 1998, you
                  will receive a payment of $800,000 (subject to withholding)
                  and if you retire on or before February 1, 1999, such payment
                  will be $400,000 (subject to withholding).

         e.       If you die before your Retirement Date, your executor or
                  designated beneficiary shall receive the payment described in
                  (c) above as though you had remained alive and retired on the
                  first day of the month following your death. For purposes of
                  TRW's benefit plans you shall have been deemed to die while
                  employed.

         f.       Upon your Early Retirement Date, you will receive one
                  additional full calendar year of Ayco services (unless
                  provided by the new employer) and 60 days of office and
                  secretarial services.


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Martin A. Coyle
April 21, 1997
Page 3

         g.       The section entitled "Early Retirement" on pages 9 and 10 of
                  the Agreement is hereby deleted.

4.       Notwithstanding anything in the Agreement, when you retire, you may
         purchase your Company Car for $1.00. You understand that the difference
         between the car's fair market value and $1.00 shall be deemed imputed
         taxable income to you.

If this represents the agreement between TRW and you, please indicate by signing
below.

Sincerely,

TRW INC.

by   /s/ Howard V. Knicely
  ----------------------------
Howard V. Knicely
Executive Vice President

Accepted and agreed to this 22nd day of April 1997

    /s/ Martin A. Coyle
----------------------------
Martin A. Coyle

Approved and agreed to this 30th day of April, 1997
Compensation and Stock Option Committee

by     /s/ William S. Kiser
  --------------------------
      Chairman